Configuration Item Reference Manual

Contains all configuration components supported by Dubbo and all configuration items supported by each configuration component

Configuration Details

application

Each application must have one and only one application configuration, corresponding configuration class: org.apache.dubbo.config.ApplicationConfig

Attribute	Corresponding URL parameter	Type	Required	Default
name	application	string	Required		Service Governance	The name of the current application, which is used by the registry to calculate dependencies between applications. Note: the consumer and provider application names should not be the same, this parameter is not Matching conditions, you can fill in the name of your current project, which has nothing to do with the role of the provider and consumer. For example, if the kylin application calls the service of the morgan application, the kylin project will be kylin, and the morgan project will be morgan. Maybe kylin also provides other The service is used by others, but the kylin project will always be dubbed kylin, so the registry will show that kylin depends on morgan	version 2.7 .0 or later
compiler	compiler	string	optional	javassist	performance optimization	Java bytecode compiler, used to generate dynamic classes, optional: jdk or javassist	version 2.7.0 or later
logger	logger	string	optional	slf4j	performance optimization	log output method, optional: slf4j, jcl, log4j, log4j2, jdk	version 2.7.0 or later
owner	owner	string	Optional		Service Governance	The person in charge of the application, used for service governance, please fill in the email prefix of the person in charge	Version above 2.0.5
organization	organization	string	Optional		Service Governance	Organization name (BU or department), which is used by the registration center to distinguish service sources. It is recommended not to use autoconfig for this configuration item, and write it directly in the configuration, such as china, intl, itu, crm, asc, dw, aliexpress, etc.	Version 2.0.0 and above
architecture	architecture	string	optional		Service Governance	. Different architectures use different layers.	Version 2.0. 7 and above
environment	environment	string	Optional		Service Governance	Application environment, such as: develop/test/product, different environments use different default values, and it is only used as a restriction for developing and testing functions	2.0.0 and above version
version	application.version	string	optional		service governance	current application version	version 2.7.0 or later
dumpDirectory	dump.directory	string	Optional		Service Governance	When the process has a problem such as the thread pool is full, the storage path of the framework’s automatic dump file	Version 2.7.0 or later
qosEnable	qos.enable	boolean	Optional		Service governance	Whether to enable the qos operation and maintenance port	Version 2.7.0 or later
qosHost	qos.host	string	Optional		Service Governance	Network interface address to monitor, default 0.0.0.0	Version 2.7.3 or later
qosPort	qos.port	int	optional		service governance	network port to monitor	version 2.7.0 or later
qosAcceptForeignIp	qos.accept.foreign.ip	boolean	Optional		Service Governance	Security configuration, whether to accept external requests except localhost local access	Version 2.7.0 or later
shutwait	dubbo.service.shutdown.wait	string	optional		service governance	shutdown waiting time (ms) during graceful shutdown	version 2.7.0 or later
hostname		string	optional	local hostname	service governance	hostname	version 2.7.5 or later
registerConsumer	registerConsumer	boolean	optional	true	service governance	whether to register the instance to the registry. Only set to `false` when the instance is a pure consumer	Version 2.7.5 and above
repository	application.version	string	optional		service governance	current application version	version 2.7.6 or later
enableFileCache	file.cache	boolean	optional	true	service governance	whether to enable local cache	version 3.0.0 or later
protocol		string	optional	dubbo	service governance	preferred protocol, applicable when the preferred protocol cannot be determined	version 3.0.0 or later
metadataType	metadata-type	String	Optional	local	Service Governance	Application-level service discovery The metadata delivery method is from the perspective of Provider, and the configuration on the Consumer side is invalid. The optional values are: * remote - Provider Put the metadata in the remote registry, and the Consumer gets it from the registry; * local - Provider puts the metadata locally, and the Consumer gets it directly from the Provider;	Version 2.7.5 and above

metadataServicePort	metadata-service-port	int	Optional		Service Governance	If metadataType is configured as local, this property sets the port number used by the MetadataService service	Version 2.7.9 or later
livenessProbe	liveness-probe	string	optional		service governance	concept and format corresponding to k8s system liveness probe	version 3.0.0 or later
readinessProbe	readiness-probe	string	optional		service governance	concept and format corresponding to k8s system readiness probe	version 3.0.0 or later
startupProbe	startup-probe	string	Optional		Service Governance	The concept and format correspond to the k8s system startup probe	Version 3.0.0 or later
registerMode	register-mode	string	Optional	all	Service Governance	Control address registration behavior, used for application-level service discovery and migration. * instance only registers application-level addresses; * interface only registers interface-level addresses; * all (default) registers both application-level and interface-level addresses;	Version 3.0.0 and above
enableEmptyProtection	enable-empty-protection	boolean	Optional	true	Service Governance	Whether to enable the protection of the empty address list on the consumer side globally. After enabling it, the empty address push from the registration center will be ignored. The default is true	Version 3.0.0 or later
parameters	None	Map<string, string>	Optional		Service Governance	Reserved for extensions, any parameters can be extended and defined, and all extended parameters will be reflected in the URL configuration as they are	Version 2.7.0 and above

service

A service provider exposes service configuration. Corresponding configuration class: org.apache.dubbo.config.ServiceConfig

Attribute	Corresponding URL parameter	Type	Required	Default
interface		class	required		service discovery	service interface name	version 1.0.0 or later
ref		object	required		service discovery	service object implementation reference	version 1.0.0 or later
version	version	string	optional	0.0.0	service discovery	service version, it is recommended to use a two-digit version, such as: 1.0, usually the version number needs to be upgraded when the interface is not compatible	version 1.0.0 or later
group	group	string	optional		service discovery	service grouping, when an interface has multiple implementations, they can be distinguished by grouping	version 1.0.7 or later
path		string	optional	default interface name	service discovery	service path (note: 1.0 does not support custom path, always use the interface name, if there is 1.0 to 2.0, the configuration service path may not be Compatible)	Version 1.0.12+
delay	delay	int	Optional	0	Performance tuning	Delayed registration service time (milliseconds), when set to -1, it means that the service is delayed until the initialization of the Spring container is completed	Version 1.0.14 and above
timeout	timeout	int	optional	1000	performance tuning	remote service call timeout (milliseconds)	version 2.0.0 or later
retries	retries	int	Optional	2	Performance tuning	The number of remote service call retries, excluding the first call, please set it to 0 if you don’t need to retry	Version 2.0.0 or later
connections	connections	int	optional	100	performance tuning	the maximum number of connections for each provider, short connection protocols such as rmi, http, and hessian indicate the limit on the number of connections, and long connection agreements such as dubbo indicate the established long connections Number	Version 2.0.0 or above
loadbalance	loadbalance	string	optional	random	performance tuning	load balancing strategy, optional values: * random - random; * roundrobin - polling; * leastactive - Least active calls; br/>* consistenthash - consistent hash (2.1.0+); * shortestresponse - shortest response (2.7.7+);	2.0.0+
async	async	boolean	Optional	false	Performance tuning	Whether to execute asynchronously by default, unreliable asynchronous, just ignore the return value, do not block the execution thread	Version above 2.0.0
local	local	class/boolean	optional	false	service governance	set to true, means to use the default proxy class name, that is: interface name + Local suffix, obsolete, please use stub	2.0.0 or above
stub	stub	class/boolean	Optional	false	Service Governance	Set to true, which means to use the default proxy class name, that is: interface name + Stub suffix, the local proxy class name of the service interface client, used in the client The client executes local logic, such as local cache, etc. The constructor of the local proxy class must allow remote proxy objects to be passed in, such as: public XxxServiceStub(XxxService xxxService)	Version 2.0.0 or later
mock	mock	class/boolean	Optional	false	Service Governance	Set to true, which means to use the default Mock class name, that is: interface name + Mock suffix, if the service interface fails to call the Mock implementation class , the Mock class must have A no-argument constructor, the difference from Local is that Local is always executed, while Mock is only executed when non-business exceptions (such as timeouts, network exceptions, etc.) occur, Local is executed before remote calls, and Mock is executed after remote calls .	Version 2.0.0 and above
token	token	string/boolean	Optional		service governance	Consumers bypass the registration center for direct access to ensure that the authorization function of the registration center is valid. If point-to-point calls are used, the token function must be turned off	version 2.0.0 or later
registry		string	optional	default registration to all registries	configuration association	registration to the specified registry, used in multiple registries, the value is the id attribute of dubbo:registry, used for multiple registries IDs Separated by commas, If you don’t want to register the service to any registry, you can set the value to N/A	Version 2.0.0 or later
provider		string	optional	the first provider configuration is used by default	configuration association	specify the provider, the value is the id attribute of dubbo:provider	version above 2.0.0
deprecated	deprecated	boolean	Optional	false	Service Governance	Whether the service is deprecated, if set to true, the consumer will print the service deprecated warning error log	2.0.5 or later
dynamic	dynamic	boolean	Optional	true	Service Governance	Whether the service is dynamically registered, if it is set to false, the disabled status will be displayed after registration, and it needs to be manually enabled, and the registration will not be canceled automatically when the service provider stops , need to be disabled manually.	Version 2.0.5 and above
accesslog	accesslog	string/boolean	optional	false	service management	set to true, the access log will be output to the logger, and the access log file path can also be filled in to output the access log directly to the specified file	2.0.5 and above version
owner	owner	string	optional		service governance
document	document	string	optional		service governance	service document URL	version 2.0.5 or later
weight	weight	int	optional		performance tuning	service weight	version 2.0.5 or later
executes	executes	int	optional	0	performance tuning	the maximum number of parallel execution requests per service and method of a service provider	version 2.0.5 or later
actives	actives	int	optional	0	performance tuning	maximum number of concurrent calls per service consumer per service per method	version 2.0.5 or later
proxy	proxy	string	optional	javassist	performance tuning	generate dynamic proxy, optional: jdk/javassist	version 2.0.5 or later
cluster	cluster	string	optional	failover	performance tuning	cluster mode, optional: failover/failfast/failsafe/failback/forking/available/mergeable (2.1. )/zone-aware (version 2.7.5 or later)	version 2.0 .5 or later
filter	service.filter	string	optional	default	performance tuning	service provider remote call process interceptor name, multiple names separated by commas	version 2.0.5 or later
listener	exporter.listener	string	optional	default	performance tuning	service provider export service listener name, multiple names separated by commas
protocol		string	optional		configuration association	use the specified protocol to expose the service, used in multi-protocol, the value is the id attribute of dubbo:protocol, multiple protocol IDs are separated by commas	version 2.0 .5 or later
layer	layer	string	optional		service governance	the layer where the service provider resides. Such as: biz, dao, intl:web, china:acton.	Version 2.0.7 and above
register	register	boolean	optional	true	service governance	whether the service of this protocol is registered to the registry	version 2.0.8 or later
validation	validation	string	optional		service governance	whether to enable JSR303 standard annotation validation, if enabled, the annotations on the method parameters will be validated	version 2.7.0 or later
parameters	None	Map<string, string>	Optional		Service Governance	Reserved for extensions, any parameters can be extended and defined, and all extended parameters will be reflected in the URL configuration as they are	Version 2.0.0 and above

reference

A service consumer references a service configuration. Corresponding configuration class: org.apache.dubbo.config.ReferenceConfig

Attribute	Corresponding URL parameter	Type	Required	Default
id		string	required		configuration association	service reference BeanId	version 1.0.0 or later
interface		class	required		service discovery	service interface name	version 1.0.0 or later
version	version	string	optional		service discovery	service version, consistent with the version of the service provider	version above 1.0.0
group	group	string	optional		service discovery	service grouping, when an interface has multiple implementations, they can be distinguished by grouping, must be consistent with the service provider	version 1.0.7 or later
timeout	timeout	long	optional	timeout of dubbo:consumer is used by default	performance tuning	service method call timeout (milliseconds)	version 1.0.5 or later
retries	retries	int	optional	retries of dubbo:consumer are used by default	performance tuning	retries of remote service calls, excluding the first call, please set to 0	2.0. Version 0 and above
connections	connections	int	optional	default connections of dubbo:consumer	performance tuning	the maximum number of connections for each provider, rmi, http, hessian and other short connection protocols indicate the limit of the number of connections, dubbo The equal-length connection association indicates the number of established long connections	Version 2.0.0 or later
loadbalance	loadbalance	string	optional	default loadbalance of dubbo:consumer	performance tuning	load balancing strategy, optional values: * random - random; * roundrobin - round * leastactive - least active call; * consistenthash - consistent hash (version 2.1.0 and above); * shortestresponse - shortest response (version 2.7.7 and above);	2.0 .0+ version
async	async	boolean	optional	async of dubbo:consumer is used by default	performance tuning	whether to execute asynchronously, unreliable and asynchronous, just ignore the return value and not block the execution thread	version 2.0.0 or later
generic	generic	boolean	optional	default dubbo:consumer generic	service governance	whether to default the generic interface, if it is a generic interface, it will return GenericService	version 2.0.0 or later
check	check	boolean	optional	default check of dubbo:consumer	service governance	check whether the provider exists at startup, true will report an error, false will ignore	version 2.0.0 or later
url	url	string	optional		service governance	point-to-point direct connection service provider address, will bypass the registration center	version 1.0.6 or later
stub	stub	class/boolean	Optional		Service Governance	The name of the service interface client’s local proxy class, which is used to execute local logic on the client, such as local cache, etc. The constructor of the local proxy class must allow input Remote proxy object, constructor such as: public XxxServiceLocal(XxxService xxxService)	version 2.0.0 or later
mock	mock	class/boolean	Optional		Service Governance	Service interface call failure Mock implementation class name, the Mock class must have a no-argument constructor, the difference from Local is that Local is always executed, while Mock Execute only When a non-business exception occurs (such as timeout, network exception, etc.), Local is executed before the remote call, and Mock is executed after the remote call.	Supported by Dubbo1.0.13 and above
cache	cache	string/boolean	Optional		Service Governance	The call parameter is used as the key to cache the returned result, optional: lru, threadlocal, jcache, etc.	Supported by Dubbo2.1.0 and above
validation	validation	boolean	optional		service governance	whether to enable JSR303 standard annotation validation, if enabled, the annotations on the method parameters will be validated	Dubbo2.1.0 and above versions support
proxy	proxy	boolean	optional	javassist	performance tuning	choose dynamic proxy implementation strategy, optional: javassist, jdk	version above 2.0.2
client	client	string	optional		performance tuning	client transport type setting, such as netty or mina of Dubbo protocol.	Supported by Dubbo2.0.0 and above
registry		string	optional	By default, the service list will be obtained from all registries and the results will be merged	Configuration Association	Register to obtain the service list from the specified registry, used when there are multiple registries, the value is dubbo:registry The id attribute, multiple registration center IDs are separated by commas	Version 2.0.0 or later
owner	owner	string	Optional		Service Governance	To call the person in charge of the service for service governance, please fill in the email prefix of the person in charge	Version above 2.0.5
actives	actives	int	optional	0	performance tuning	maximum number of concurrent calls per service consumer per service per method	version 2.0.5 or later
cluster	cluster	string	optional	failover	performance tuning	cluster mode, optional: failover/failfast/failsafe/failback/forking/available/mergeable (2.1. )/zone-aware (version 2.7.5 or later)	version 2.0 .5 or later
connections	connections	int	optional	100	performance tuning	the maximum number of connections for each provider, short connection protocols such as rmi, http, and hessian indicate the limit on the number of connections, and long connection agreements such as dubbo indicate the established long connections Number	Version 2.0.0 or above
filter	reference.filter	string	optional	default	performance tuning	service consumer remote call process interceptor name, multiple names separated by commas	version 2.0.5 or later
listener	invoker.listener	string	optional	default	performance tuning	The service consumer quotes the name of the service listener, and multiple names are separated by commas	Version 2.0.5 or later
layer	layer	string	optional		service governance	the layer where the service caller resides. Such as: biz, dao, intl:web, china:acton.	Version 2.0.7 and above
init	init	boolean	optional	false	Performance tuning	Whether to starvely initialize the reference when afterPropertiesSet(), otherwise wait until someone injects or references the instance before initializing.	Version 2.0.10 and above
protocol	protocol	string	optional		service governance	only call the service provider of the specified protocol, and ignore other protocols.	Version 2.7.0 and above
client	client	string	optional	dubbo protocol defaults to netty	service discovery	protocol client implementation type, such as: dubbo protocol mina, netty, etc.	version 2.7.0 or later
providerPort	provider-port	int	Optional		Service Mesh	When dubbo.consumer.meshEnable=true, Dubbo will convert the request to K8S standard format by default, and combine VirtualService and DestinationRule for traffic management. At this time, the consumer can perceive to provider. If you don’t want to use VirtualService and DestinationRule, please set providerPort to make the consumer aware of the service port exposed by the provider	Version 3.1.0 and above
unloadClusterRelated	unloadClusterRelated	boolean	Optional	false	Service Mesh	When dubbo.consumer.meshEnable=true, in Service Mesh mode, set it to true to unload the Directory, Router and Load Balance related to the Cluster in the current call , Delegate retry, load balancing, timeout and other traffic management functions to Sidecar, use VirtualService and DestinationRule for traffic management	Version 3.1.0 and above
parameters	None	Map<string, string>	Optional		Service Governance	Reserved for extensions, any parameters can be extended and defined, and all extended parameters will be reflected in the URL configuration as they are	Version 2.0.0 and above
providedBy	provided-by	string	Optional		Service Mesh	When dubbo.consumer.meshEnable=true, Dubbo will convert the request to K8S standard format by default, and combine VirtualService and DestinationRule for traffic management. At this time, the consumer can perceive to provider. The value should be consistent with the declared `k8s service`	Version 3.1.0 or later
providerNamespace	provider-namespace	string	Optional		Service Mesh	When dubbo.consumer.meshEnable=true, Dubbo will convert the request into K8S standard format by default, and combine VirtualService and DestinationRule for traffic management. At this time, the Consumer can perceive to provider. Please set the providerNamespace so that the consumer can address the provider dns according to this configuration, the default `default`	version 3.1.2 or later

registry

Registry configuration. Corresponding configuration class: org.apache.dubbo.config.RegistryConfig. At the same time, if there are multiple different registries, you can declare multiple <dubbo:registry> tags, and specify the registry to use in the registry attribute of <dubbo:service> or <dubbo:reference> .

Attribute	Corresponding URL parameter	Type	Required	Default
id		string	optional		configuration association	the registration center references the BeanId, which can be referenced in <dubbo:service registry=""> or <dubbo:reference registry="">	version 1.0.16 or later
address	host:port	string	Required		Service discovery	The address of the registration center server. If the address has no port, the default is 9090. Multiple addresses in the same cluster are separated by commas. Such as: ip:port, ip:port, registry centers of different clusters, please configure multiple dubbo:registry tags	Version 1.0.16 or later
protocol		string	optional	dubbo	service discovery	registry address protocol, support `dubbo`, `multicast`, `zookeeper`, `redis`, `consul(2.7. .2)`, `etcd( 2.7.2)`, `nacos(2.7.2)` and other protocols	Version 2.0.0 and above
port		int	optional	9090	service discovery	the default port of the registry, when the address does not have a port, use this port as the default value	version 2.0.0 or later
username		string	Optional		Service Governance	Username for logging in to the registration center, if the registration center does not require verification, it can be left blank	Version 2.0.0 or later
password		string	Optional		Service Governance	Password for logging in to the registration center, if the registration center does not require verification, you can leave it blank	Version 2.0.0 or later
transport	registry.transporter	string	optional	netty	performance tuning	network transport mode, optional mina, netty	version 2.0.0 or later
timeout	registry.timeout	int	optional	5000	performance tuning	registry center request timeout (milliseconds)	version 2.0.0 or later
session	registry.session	int	optional	60000	Performance tuning	Registry session timeout (milliseconds), used to detect dirty data after abnormal disconnection of the provider, such as the implementation of heartbeat detection, this time It is the heartbeat interval , which is different for different registration centers.	Version 2.1.0 and above
zone	zone	string	optional		service governance	the region to which the registry belongs, usually used for traffic isolation	version 2.7.5 or later
file	registry.file	string	Optional		Service Governance	Use a file to cache the registry address list and service provider list. When the application is restarted, it will be restored based on this file. Note: two registries cannot use the same file storage	Version 2.0.0 or later
wait	registry.wait	int	optional	0	performance tuning	wait notification completion time (milliseconds) when stopping	version 2.0.0 or later
check	check	boolean	optional	true	service governance	whether to report an error when the registration center does not exist	version 2.0.0 or later
register	register	boolean	Optional	true	Service Governance	Whether to register the service with this registry, if set to false, it will only subscribe and not register	Version 2.0.5 and above
subscribe	subscribe	boolean	optional	true	service governance	whether to subscribe to this registry service, if set to false, it will only register, not subscribe	version 2.0.5 or later
dynamic	dynamic	boolean	Optional	true	Service Governance	Whether the service is dynamically registered, if it is set to false, it will be displayed as disabled after registration, it needs to be manually enabled, and when the service provider stops , it will not be automatically unregistered , need to be disabled manually.	Version 2.0.5 and above
group	group	string	Optional	dubbo	Service Governance	Service registration grouping, cross-group services will not affect each other, and cannot call each other, suitable for environment isolation.	Version 2.0.5 and above
version	version	string	optional		service discovery	service version	version above 1.0.0
simplified	simplified	boolean	optional	false	service governance	whether the URL registered to the registration center is in simplified mode (compatible with lower versions)	version 2.7.0 or later
extra-keys	extraKeys	string	Optional		Service Governance	When simplified=true, extraKeys allows you to put extra keys in the URL besides the default parameters, in the format: “interface,key1,key2”.	Version 2.7 .0 and above
useAsConfigCenter		boolean	optional		service governance	whether the registry is used as a configuration center	version 2.7.5 or later
useAsMetadataCenter		boolean	optional		service governance	whether the registry is used as a metadata center	version 2.7.5 or later
accepts	accepts	string	Optional		Service Governance	The registry receives a list of rpc protocols, multiple protocols are separated by commas, such as dubbo, rest	version 2.7.5 or later
preferred	preferred	boolean	optional		service governance	whether to be the preferred registry. When subscribing to multiple registries, if set to true, the registries will be preferred	Version 2.7.5 and above
weight	weight	int	optional		performance tuning	registration traffic weight. When using multiple registries, you can use this value to adjust the distribution of registration traffic. This value does not take effect when setting the preferred registry	Version 2.7. 5 or later
registerMode	register-mode	string	Optional	all	Service Governance	Control address registration behavior, used for application-level service discovery and migration. * instance only registers application-level addresses; * interface only registers interface-level addresses; * all (default) registers both application-level and interface-level addresses;	Version 3.0.0 and above
enableEmptyProtection	enable-empty-protection	boolean	Optional	true	Service Governance	Whether to enable the protection of the empty address list on the consumer side globally. After enabling it, the empty address push from the registration center will be ignored. The default is true	Version 3.0.0 or later
parameters	None	Map<string, string>	Optional		Service Governance	Reserved for extensions, any parameters can be extended and defined, and all extended parameters will be reflected in the URL configuration as they are	Version 2.0.0 and above

config-center

configuration center. Corresponding configuration class: org.apache.dubbo.config.ConfigCenterConfig

metadata-report-config

metadata center. Corresponding configuration class: org.apache.dubbo.config.MetadataReportConfig

protocol

Service provider protocol configuration. Corresponding configuration class: org.apache.dubbo.config.ProtocolConfig. At the same time, if you need to support multiple protocols, you can declare multiple <dubbo:protocol> tags, and specify the used protocol through the protocol attribute in <dubbo:service>.

Attribute	Corresponding URL parameter	Type	Required	Default
id		string	optional	dubbo	configuration association	protocol BeanId, you can refer to this ID in <dubbo:service protocol="">, if the ID is not filled, the default is the same as the value of the name attribute, and if it is repeated, it will be in the name followed by the serial number.	Version 2.0.5 and above
name		string	Required	dubbo	Performance tuning	Protocol name	Version above 2.0.5
port		int	optional	The default port of dubbo protocol is 20880, the default port of rmi protocol is 1099, the default port of http and hessian protocol is 80; if no port is configured, The default port will be used automatically, if configured as -1, an unoccupied port will be allocated. For Dubbo 2.4.0+, the allocated port is increased on the basis of the default port of the protocol to ensure that the port segment is controllable.	Service Discovery	Service Port	Version 2.0.5 and above
host		string	Optional	Automatically find local IP	Service discovery	- Service host name, used when selecting multiple network cards or specifying VIP and domain name, if it is empty, it will automatically find local IP, - it is recommended not to configure , let Dubbo automatically obtain the local IP	version 2.0.5 or later
threadpool	threadpool	string	optional	fixed	performance tuning	thread pool type, optional: fixed/cached/limit (above 2.5.3)/eager (above 2.6.x)	version 2.0.5 or above
threadname	threadname	string	optional		performance tuning	thread pool name	version 2.7.6 or later
threads	threads	int	optional	200	performance tuning	service thread pool size (fixed size)	version 2.0.5 or later
corethreads	corethreads	int	optional	200	performance tuning	thread pool core thread size	version 2.0.5 or later
iothreads	threads	int	optional	number of cpus + 1	performance tuning	io thread pool size (fixed size)	version 2.0.5 or later
accepts	accepts	int	optional	0
payload	payload	int	optional	8388608(=8M)	performance tuning	request and response packet size limit, unit: byte	version 2.0.5 or later
codec	codec	string	optional	dubbo	performance tuning	protocol encoding	version 2.0.5 or later
serialization	serialization	string	optional	dubbo protocol defaults to hessian2, rmi protocol defaults to java, http protocol defaults to json	performance tuning	protocol serialization method, used when the protocol supports multiple serialization methods , such as: dubbo, hessian2, java, compactedjava of dubbo protocol, and json of http protocol, etc.	Version 2.0.5 and above
accesslog	accesslog	string/boolean	Optional		Service Governance	Set to true, the access log will be output to the logger, you can also fill in the access log file path, directly output the access log to the specified file	Version 2.0.5 or later
path		string	optional		service discovery	provider context path, prefix of service path	version 2.0.5 or later
transporter	transporter	string	optional	dubbo protocol defaults to netty	performance tuning	protocol server and client implementation types, such as: dubbo protocol mina, netty, etc., can be split into server and client configuration	Version 2.0.5 and above
server	server	string	Optional	Dubbo protocol defaults to netty, http protocol defaults to servlet	Performance tuning	The server-side implementation type of the protocol, such as: mina, netty of dubbo protocol, etc., jetty of http protocol, servlet, etc.	Version 2.0.5 and above
client	client	string	Optional	Dubbo protocol defaults to netty	Performance tuning	Protocol client implementation type, such as: dubbo protocol mina, netty, etc.	Version 2.0.5 or later
dispatcher	dispatcher	string	optional	dubbo protocol defaults to all	performance tuning	protocol message distribution method, used to specify the thread model, such as: all, direct, message, execution, connection, etc. of dubbo protocol	2.1 .0+ version
queues	queues	int	optional	0	performance tuning	thread pool queue size, when the thread pool is full, the size of the queue waiting to be executed, it is recommended not to set, when the thread pool is full, it should fail immediately, and retry other Serving provisioning machines, rather than queuing, unless there is a special need.	Version 2.0.5 and above
charset	charset	string	optional	UTF-8	performance tuning	serialization encoding	version 2.0.5 or later
buffer	buffer	int	optional	8192	performance tuning	network read and write buffer size	version 2.0.5 or later
heartbeat	heartbeat	int	Optional	0	Performance Tuning	A heartbeat is required to help check if a connection is broken	2.0.10+
telnet	telnet	string	Optional		Service Governance	Supported telnet commands, separated by commas	Version 2.0.5 and above
register	register	boolean	optional	true	service governance	whether the service of this protocol is registered to the registry	version 2.0.8 or later
contextpath	contextpath	String	optional	default is empty string	service governance	context path	version 2.0.6 or later
sslEnabled	ssl-enabled	boolean	optional	false	service governance	whether to enable ssl	version 2.7.5 or later
parameters	parameters	Map<string, string>	optional		extended parameters	version 2.0.0 or later

provider

Service provider default configuration. Corresponding configuration class: org.apache.dubbo.config.ProviderConfig. At the same time, this tag is the default value setting of <dubbo:service> and <dubbo:protocol> tags.

Attribute	Corresponding URL parameter	Type	Required	Default
id		string	optional	dubbo	configuration association	protocol BeanId, you can refer to this ID in <dubbo:service proivder="">	version above 1.0.16
protocol		string	optional	dubbo	performance tuning	protocol name	version 1.0.16 or later
host		string	Optional	Automatically search for local IP	Service discovery	Service host name, used when selecting multiple network cards or specifying VIP and domain name, if it is empty, it will automatically search for local IP. Dubbo automatically obtains the local IP	version 1.0.16 or later
threads	threads	int	optional	200	performance tuning	service thread pool size (fixed size)	version 1.0.16 or later
payload	payload	int	optional	8388608(=8M)	performance tuning	request and response packet size limit, unit: byte	version above 2.0.0
path		string	optional		service discovery	provider context path, prefix of service path	version 2.0.0 or later
transporter	transporter	string	optional	dubbo protocol defaults to netty	performance tuning	protocol server and client implementation types, such as: dubbo protocol mina, netty, etc., can be split into server and client configuration	Version 2.0.5 and above
server	server	string	Optional	Dubbo protocol defaults to netty, http protocol defaults to servlet	Performance tuning	The server-side implementation type of the protocol, such as: mina, netty of dubbo protocol, etc., jetty of http protocol, servlet, etc.	Version 2.0.0 and above
client	client	string	Optional	Dubbo protocol defaults to netty	Performance tuning	Protocol client implementation type, such as: dubbo protocol mina, netty, etc.	Version 2.0.0 or later
dispatcher	dispatcher	string	optional	dubbo protocol defaults to all	performance tuning	protocol message distribution method, used to specify the thread model, such as: all, direct, message, execution, connection, etc. of dubbo protocol	2.1 .0+ version
codec	codec	string	optional	dubbo	performance tuning	protocol encoding	version 2.0.0 or later
serialization	serialization	string	optional	dubbo protocol defaults to hessian2, rmi protocol defaults to java, http protocol defaults to json	performance tuning	protocol serialization method, used when the protocol supports multiple serialization methods , such as: dubbo, hessian2, java, compactedjava of the dubbo protocol, and json, xml of the http protocol	Version 2.0.5 and above
default		boolean	optional	false	configuration association	whether it is the default protocol, used for multi-protocol	version 1.0.16 or later
filter	service.filter	string	optional		performance tuning	service provider remote call process interceptor name, multiple names separated by commas	version 2.0.5 or later
listener	exporter.listener	string	optional		performance tuning	service provider export service listener name, multiple names separated by commas	version 2.0.5 or later
threadpool	threadpool	string	optional	fixed	performance tuning	thread pool type, optional: fixed/cached/limit (above 2.5.3)/eager (above 2.6.x)	version 2.0.5 or above
threadname	threadname	string	optional		performance tuning	thread pool name	version 2.7.6 or later
accepts	accepts	int	optional	0
version	version	string	optional	0.0.0	service discovery	service version, it is recommended to use a two-digit version, such as: 1.0, usually the version number needs to be upgraded when the interface is incompatible	version 2.0.5 or later
group	group	string	optional		service discovery	service grouping, when an interface has multiple implementations, they can be distinguished by grouping	version 2.0.5 or later
delay	delay	int	Optional	0	Performance tuning	Delayed registration service time (milliseconds) - When set to -1, it means that the service is delayed until the initialization of the Spring container is completed	Version 2.0.5 and above
timeout	default.timeout	int	optional	1000	performance tuning	remote service call timeout (milliseconds)	version 2.0.5 or later
retries	default.retries	int	optional	2	Performance tuning	The number of remote service call retries, excluding the first call, please set it to 0 if you don’t need to retry	Version 2.0.5 or later
connections	default.connections	int	optional	0	performance tuning	the maximum number of connections for each provider, short connection protocols such as rmi, http, and hessian indicate the limit on the number of connections, long connection agreements such as dubbo indicate the established The number of long connections	Version 2.0.5 and above
loadbalance	default.loadbalance	string	optional	random	performance tuning	load balancing strategy, optional values: * random - random; * roundrobin - round robin; leastactive - least active call; * consistenthash - consistent hash (2.1.0+); * shortestresponse - shortest response (2.7.7+);	2.0.5+
async	default.async	boolean	optional	false	performance tuning	whether to execute asynchronously by default, unreliable and asynchronous, just ignore the return value and not block the execution thread	Version 2.0.5 and above
stub	stub	boolean	Optional	false	Service Governance	If set to true, it means to use the default proxy class name, namely: interface name + Local suffix.	Version 2.0.5 and above
mock	mock	boolean	Optional	false	Service Governance	Set to true to use the default Mock class name, namely: interface name + Mock suffix.	Version 2.0.5 and above
token	token	boolean	Optional		Service Governance	Token verification, empty means not enabled, if true, means randomly generated dynamic tokens	Version 2.0.5 and above
registry	registry	string	optional	register with all registries by default	configuration association	register with the specified registry, used when there are multiple registries, the value is the id attribute of dubbo:registry, multiple registry IDs Separated by commas, if you do not want to register the service to any registry, you can set the value to N/A	Version 2.0.5 or later
dynamic	dynamic	boolean	Optional	true	Service Governance	Whether the service is dynamically registered, if it is set to false, the disabled status will be displayed after registration, and it needs to be manually enabled, and the registration will not be canceled automatically when the service provider stops , need to be disabled manually.	Version 2.0.5 and above
accesslog	accesslog	string/boolean	optional	false	service management	set to true, the access log will be output to the logger, and the access log file path can also be filled in to output the access log directly to the specified file	2.0.5 and above version
owner	owner	string	optional		service governance
document	document	string	optional		service governance	service document URL	version 2.0.5 or later
weight	weight	int	optional		performance tuning	service weight	version 2.0.5 or later
executes	executes	int	optional	0	performance tuning	the maximum number of parallel execution requests per service and method of a service provider	version 2.0.5 or later
actives	default.actives	int	optional	0	performance tuning	maximum number of concurrent calls per service consumer per service per method	version 2.0.5 or later
proxy	proxy	string	optional	javassist	performance tuning	generate dynamic proxy, optional: jdk/javassist	version 2.0.5 or later
cluster	default.cluster	string	optional	failover	performance tuning	cluster mode, optional: failover/failfast/failsafe/failback/forking	version above 2.0.5
deprecated	deprecated	boolean	Optional	false	Service Governance	Whether the service is deprecated, if set to true, the consumer will print the service deprecated warning error log	2.0.5 or later
queues	queues	int	optional	0	performance tuning	thread pool queue size, when the thread pool is full, the size of the queue waiting to be executed, it is recommended not to set, when the thread pool is full, it should fail immediately, and retry other Serving provisioning machines, rather than queuing, unless there is a special need.	Version 2.0.5 and above
charset	charset	string	optional	UTF-8	performance tuning	serialization encoding	version 2.0.5 or later
buffer	buffer	int	optional	8192	performance tuning	network read and write buffer size	version 2.0.5 or later
iothreads	iothreads	int	Optional	CPU + 1	Performance tuning	IO thread pool, receive network read and write interrupts, serialize and deserialize, do not process business, business thread pool see threads configuration, this thread pool It is related to the CPU and is not recommended to be configured.	Version 2.0.5 and above
alive	alive	int	optional		service management	thread pool keepAliveTime, the default unit is ms	version 2.0.5 or later
telnet	telnet	string	Optional		Service Governance	Supported telnet commands, separated by commas	Version 2.0.5 and above
wait	wait	int	Optional		Service Governance	Waiting time when stopping the service
contextpath	contextpath	String	optional	default is empty string	service governance	context path	version 2.0.6 or later
layer	layer	string	optional		service governance	the layer where the service provider resides. Such as: biz, dao, intl:web, china:acton.	Version 2.0.7 and above
parameters	parameters	Map<string, string>	optional		service governance	extended parameters	version 2.0.0 or later

consumer

Service consumer default configuration. Configuration class: org.apache.dubbo.config.ConsumerConfig. At the same time, this tag is the default value setting of the <dubbo:reference> tag.

Attribute	Corresponding URL parameter	Type	Required	Default
timeout	default.timeout	int	optional	1000	performance tuning	remote service call timeout (milliseconds)	version 1.0.16 or later
retries	default.retries	int	optional	2	Performance tuning	The number of remote service call retries, excluding the first call, please set it to 0 if you do not need to retry, it is only valid when the cluster is failback/failover	Version 1.0.16 and above
loadbalance	default.loadbalance	string	optional	random	performance tuning	load balancing strategy, optional values: * random - random; * roundrobin - round robin; leastactive - least active call; * consistenthash - consistent hash (2.1.0+); * shortestresponse - shortest response (2.7.7+);	1.0.16+
async	default.async	boolean	optional	false	performance tuning	whether to execute asynchronously by default, unreliable and asynchronous, just ignore the return value and not block the execution thread	Version 2.0.0 or later
sent	default.sent	boolean	optional	true	service governance	when calling asynchronously, when the flag sent=true, it means that the network has sent data	version 2.0.6 or later
connections	default.connections	int	optional	100	performance tuning	the maximum number of connections for each service to each provider, rmi, http, hessian and other short connection protocols support this configuration, dubbo protocol long connection does not support This configuration	1.0.16+ version
generic	generic	boolean	optional	false	service governance	whether to default the generic interface, if it is a generic interface, it will return GenericService	version above 2.0.0
check	check	boolean	Optional	true	Service Governance	Check whether the provider exists at startup, true reports an error, false ignores	version 1.0.16 and above
proxy	proxy	string	optional	javassist	performance tuning	generate dynamic proxy, optional: jdk/javassist	version 2.0.5 or later
owner	owner	string	Optional		Service Governance	To call the person in charge of the service for service governance, please fill in the email prefix of the person in charge	Version above 2.0.5
actives	default.actives	int	optional	0	performance tuning	maximum number of concurrent calls per service consumer per service per method	version 2.0.5 or later
cluster	default.cluster	string	optional	failover	performance tuning	cluster mode, optional: failover/failfast/failsafe/failback/forking/available/mergeable (2.1. above)/zone-aware(2.7.5 above)	2.0.5 above
filter	reference.filter	string	optional		performance tuning	service consumer remote call process interceptor name, multiple names separated by commas	version 2.0.5 or later
listener	invoker.listener	string	optional		performance tuning	the service consumer quotes the name of the service listener, multiple names are separated by commas	version 2.0.5 or later
registry		string	optional	default registration to all registries	configuration association	registration to the specified registry, used in multiple registries, the value is the id attribute of dubbo:registry, used for multiple registries IDs Separated by commas, if you do not want to register the service to any registry, you can set the value to N/A	Version 2.0.5 or later
layer	layer	string	optional		service governance	the layer where the service caller resides. Such as: biz, dao, intl:web, china:acton.	Version 2.0.7 and above
init	init	boolean	optional	false	Performance tuning	Whether to starvely initialize the reference when afterPropertiesSet(), otherwise wait until someone injects or references the instance before initializing.	Version 2.0.10 and above
cache	cache	string/boolean	Optional		Service Governance	The call parameter is used as the key to cache the returned result, optional: lru, threadlocal, jcache, etc.	Supported by version 2.1.0 and above
validation	validation	boolean	optional		service governance	whether to enable JSR303 standard annotation validation, if enabled, the annotations on the method parameters will be validated	2.1.0 and above version support
version	version	string	optional		service governance	configure multiple versions for the same service in Dubbo	2.2.0 and above versions support
client	client	string	Optional	Dubbo protocol defaults to netty	Performance tuning	Protocol client implementation type, such as: dubbo protocol mina, netty, etc.	Version 2.0.0 or later
threadpool	threadpool	string	optional	fixed	performance tuning	thread pool type, optional: fixed/cached/limit (above 2.5.3)/eager (above 2.6.x)	version 2.0.5 or above
corethreads	corethreads	int	optional	200	performance tuning	thread pool core thread size	version 2.0.5 or later
threads	threads	int	optional	200	performance tuning	service thread pool size (fixed size)	version 2.0.5 or later
queues	queues	int	optional	0	performance tuning	thread pool queue size, when the thread pool is full, the size of the queue waiting to be executed, it is recommended not to set, when the thread pool is full, it should fail immediately, and retry other Serving provisioning machines, rather than queuing, unless there is a special need.	Version 2.0.5 and above
shareconnections	shareconnections	int	optional	1	performance tuning	number of shared connections. When the connection parameter is set to 0, the shared mode connection will be enabled, and there is only one connection by default. Only supports dubbo protocol	version 2.7.0 and above
referThreadNum		int	optional		performance optimization	thread pool size for asynchronous calls	version 3.0.0 or later
meshEnable	mesh-enable	boolean	optional	false	Service Mesh	Dubbo Mesh mode switch. After it is turned on, it can adapt to the SideCar mode and convert Dubbo service calls to K8S standard calls. Only supports the Triple protocol and is compatible with GRPC. After setting to true, the native docking K8S, no third-party registration center is required, just set dubbo.registry.address=N/A	Version 3.1.0 or later
parameters	parameters	Map<string, string>	optional		service governance	extended parameters	version 2.0.0 or later

metrics

Indicator configuration. Configuration class: org.apache.dubbo.config.MetricsConfig

Attribute	Corresponding URL parameter	Type	Required	Default
protocol	protocol	string	optional	prometheus	performance tuning	protocol name, prometheus is used by default	version 3.0.0 or later
prometheus		PrometheusConfig	optional		configuration association	prometheus related configuration	version 3.0.0 or later
aggregation		AggregationConfig	Optional		Configuration association	Indicator aggregation related configuration	Version 3.0.0 or later

PrometheusConfig corresponding class: org.apache.dubbo.config.nested.PrometheusConfig

Attribute	Type	Required	Description
exporter.enabled	boolean	optional	whether to enable prometheus exporter
exporter.enableHttpServiceDiscovery	boolean	optional	whether to enable http service discovery
exporter.httpServiceDiscoveryUrl	string	optional	http service discovery URL
exporter.metricsPort	int	optional	port number to expose when using the pull method
exporter.metricsPath	string	optional	path to expose metrics when using pull method
pushgateway.enabled	boolean	optional	whether to publish metrics through the Pushgateway of prometheus
pushgateway.baseUrl	string	optional	Pushgateway address
pushgateway.username	string	optional	Pushgateway username
pushgateway.password	string	optional	Pushgateway password
pushgateway.pushInterval	int	optional	push indicator interval time

AggregationConfig corresponding class: org.apache.dubbo.config.nested.AggregationConfig

Attribute	Type	Required	Description
enabled	boolean	optional	Whether to enable the local indicator aggregation function
bucketNum	int	optional	the number of time window buckets
timeWindowSeconds	int	optional	time window duration (s)

ssl

TLS authentication configuration. Configuration class: org.apache.dubbo.config.SslConfig

Attribute	Corresponding URL parameter	Type	Required
serverKeyCertChainPath	server-key-cert-chain-path	string	optional	security configuration
serverPrivateKeyPath	server-private-key-path	string	optional	security configuration	server private key path	version 2.7.5 or later
serverKeyPassword	server-key-password	string	optional	security configuration	server key password	version 2.7.5 or later
serverTrustCertCollectionPath	server-trust-cert-collection-path	string	optional	security configuration	server trust certificate path	version 2.7.5 or later
clientKeyCertChainPath	client-key-cert-chain-path	string	optional	security configuration	client signature certificate path	version 2.7.5 or later
clientPrivateKeyPath	client-private-key-path	string	optional	security configuration	client private key path	version 2.7.5 or later
clientKeyPassword	client-key-password	string	optional	security configuration	client key password	version 2.7.5 or later
clientTrustCertCollectionPath	client-trust-cert-collection-path	string	optional	security configuration	client trust certificate path	version 2.7.5 or later

module

Module information configuration. The corresponding configuration class org.apache.dubbo.config.ModuleConfig

Attribute	Corresponding URL parameter	Type	Required
name	module	string	Required	Service Governance	Current module name, used by the registry to calculate dependencies between modules	Version 2.2.0 or later
version	module.version	string	optional	service governance	current module version	version 2.2.0 or later
owner	module.owner	string	Optional	Service Governance	The person in charge of the module, used for service governance, please fill in the email prefix of the person in charge	Version above 2.2.0
organization	module.organization	string	Optional	Service Governance	Organization name (BU or department), which is used by the registration center to distinguish service sources. It is recommended not to use autoconfig for this configuration item, and write it directly in the configuration, such as China, intl, itu, crm, asc, dw, aliexpress, etc.	Version 2.2.0 and above
background	background	boolean	optional	performance tuning	whether to enable the background startup mode. If enabled, there is no need to wait for the spring ContextRefreshedEvent event to complete	Version 3.0.0 and above
referAsync	referAsync	boolean	Optional	Performance tuning	Whether to enable asynchronous calls on the consumer side	Version 3.0.0 or later
referThreadNum	referThreadNum	int	optional	performance tuning	thread pool size for asynchronous calls	version 3.0.0 or later
exportAsync	exportAsync	boolean	Optional	Performance tuning	Whether export is enabled on the server	Version 3.0.0 or later
exportThreadNum	exportThreadNum	int	optional	asynchronous export thread pool size		version 3.0.0 or later

monitor

Monitoring center configuration. Corresponding configuration class: org.apache.dubbo.config.MonitorConfig

Attribute	Corresponding URL parameter	Type	Required	Default
protocol	protocol	string	optional	dubbo	service governance	monitoring center protocol, if it is protocol=“registry”, it means that the address of the monitoring center is found from the registry, otherwise it is directly connected to the monitoring center.	Version 2.0.9 and above
address		string	Optional		Service Governance	Directly connected to the monitoring center server address, address=“10.20.130.230:12080”	Version 1.0.16 or later
username	username	string	optional		service governance	monitoring center username	version 2.0.9 or later
password	password	string	optional		service governance	monitoring center password	version 2.0.9 or later
group	group	string	optional		service governance	grouping	version 2.0.9 or later
version	version	string	optional		service governance	version number	version 2.0.9 or later
interval	interval	string	optional		service governance	interval time	version 2.0.9 or later
parameters	parameters	Map<string, string>	optional		custom parameters	version 2.0.0 or later

method

Method-level configuration. Corresponding configuration class: org.apache.dubbo.config.MethodConfig. At the same time, this tag is a sub-tag of service or reference, which is used to control to the method level.

for example:

<dubbo:reference interface="com.xxx.XxxService">
   <dubbo:method name="findXxx" timeout="3000" retries="2" />
</dubbo:reference>

Attribute	Corresponding URL parameter	Type	Required	Default
name		string	required		logo	method name	version 1.0.8 or later
timeout	.timeout	int	optional	default is timeout	performance tuning	method call timeout (milliseconds)	version 1.0.8 or later
retries	.retries	int	optional	The default is retries of dubbo:reference	Performance tuning	The number of retries for remote service calls, excluding the first call, please set it to 0	Version 2.0.0 or higher
loadbalance	.loadbalance	string	optional	default is loadbalance	performance tuning	load balancing strategy, optional values: * random - random; * roundrobin - polling ; * leastactive - least active call; * consistenthash - consistent hash (version 2.1.0+); * shortestresponse - shortest response (version 2.7.7+);	2.0. Version 0 and above
async	.async	boolean	Optional	The default is async of dubbo:reference	Performance tuning	Whether to execute asynchronously, unreliable and asynchronous, just ignore the return value and not block the execution thread	1.0.9 above version
sent	.sent	boolean	Optional	true	Performance tuning	When calling asynchronously, when the mark sent=true, it means that the network has sent data	Version 2.0.6 or later
actives	.actives	int	optional	0	performance tuning	maximum concurrent call limit for each service consumer	version 2.0.5 or later
executes	.executes	int	optional	0	performance tuning	the maximum number of threads used per service and method - -, this attribute is only used when dubbo:method is used as a subtag of dubbo:service Valid	Version 2.0.5 and above
deprecated	.deprecated	boolean	Optional	false	Service Governance	Whether the service method is deprecated, this attribute is only valid when dubbo:method is used as a subtag of dubbo:service	Version above 2.0.5
sticky	.sticky	boolean	optional	false	service governance	set true All methods on this interface use the same provider. If you need more complex rules, please use routing	2.0.6 or later
return	.return	boolean	Optional	true	Performance tuning	Whether the method call needs to return a value. It will take effect only when async is set to true. If it is set to true, it will return future, or call back methods such as onreturn. If set to false, Null will be returned directly after the request is sent successfully	Versions above 2.0.6
oninvoke	attribute attribute, not reflected in the URL	String	Optional		Performance tuning	Intercept before instance execution	Version 2.0.6 or later
onreturn	attribute attribute, not reflected in the URL	String	Optional		Performance tuning	Intercept after instance execution returns
onthrow	attribute attribute, not reflected in the URL	String	optional		performance tuning	exception interception in instance execution
oninvokeMethod	attribute attribute, not reflected in the URL	String	Optional		Performance tuning	Intercept before method execution	Version 2.0.6 or later
onreturnMethod	attribute attribute, not reflected in the URL	String	Optional		Performance tuning	Intercept after method execution returns	Version above 2.0.6
onthrowMethod	attribute attribute, not reflected in the URL	String	Optional		Performance tuning	Method execution has exception interception	Version 2.0.6 or later
cache	.cache	string/boolean	Optional		Service Governance	Use the call parameter as the key to cache the returned result, optional: lru, threadlocal, jcache, etc.	Version above 2.1.0
validation	.validation	boolean	Optional		Service Governance	Whether to enable JSR303 standard annotation validation, if enabled, the annotations on method parameters will be validated	Version 2.1.0 or later

argument

Method parameter configuration. Corresponding configuration class: org.apache.dubbo.config.ArgumentConfig. This tag is a sub-tag of method, which is used to describe the characteristics of method parameters, such as XML format:

<dubbo:method name="findXxx" timeout="3000" retries="2">
   <dubbo:argument index="0" callback="true" />
</dubbo:method>

Attribute	Corresponding URL parameter	Type	Required
index		int	required	identifier	parameter index	version 2.0.6 or later
type		String	choose one of index and index	identification	find parameter index by parameter type	version 2.0.6 or later
callback	.callback	boolean	optional	service governance	whether the parameter is a callback interface, if it is callback, the service provider will generate a reverse proxy, and the consumer can be reversely called from the service provider , usually used for event push.	Versions above 2.0.6

parameter

Option parameter configuration. Corresponding configuration class: java.util.Map. At the same time, the label is a sub-label of protocol or service or provider or reference or consumer or monitor or registry or metadata-config or config-center, used for configuration Custom parameters, this configuration item will be used as an extension point to set custom parameters.

for example:

<dubbo:protocol name="napoli">
   <dubbo:parameter key="http://10.20.160.198/wiki/display/dubbo/napoli.queue.name" value="xxx" />
</dubbo:protocol>

You can also:

<dubbo:protocol name="jms" p:queue="xxx" />

Attribute	Corresponding URL parameter	Type	Required	Default
key	key	string	Required		Service governance	Routing parameter key	Version 2.0.0 or later
value	value	string	Required		Service governance	Routing parameter value	Version 2.0.0 or later

Environment variables

The supported keys are the following two:

dubbo.labels, specify a list of key-value pairs configured in the URL, usually through JVM -D or system environment variables.
Add the following configuration:
```
# JVM
-Ddubbo.labels = "tag1=value1; tag2=value2"
# environment variables
DUBBO_LABELS = "tag1=value1; tag2=value2"
```
The final generated URL will contain two keys tag1 and tag2: dubbo://xxx?tag1=value1&tag2=value2
dubbo.env.keys, specify the environment variable key value, Dubbo will try to load each key from the environment variable
```
# JVM
-Ddubbo.env.keys="DUBBO_TAG1, DUBBO_TAG2"
# environment variables
DUBBO_ENV_KEYS = "DUBBO_TAG1, DUBBO_TAG2"
```
The final generated URL will contain two keys DUBBO_TAG1 and DUBBO_TAG2: dubbo://xxx?DUBBO_TAG1=value1&DUBBO_TAG2=value2

Other configuration

config-mode

background

Some types of configuration class instances can only appear once in each dubbo application (such as ApplicationConfig, MonitorConfig, MetricsConfig, SslConfig, ModuleConfig), and some can appear multiple times (such as RegistryConfig , ProtocolConfig, etc.).

If the application accidentally scans multiple unique configuration class instances (for example, the user misconfigures two ApplicationConfig in a dubbo application), which strategy should be used to deal with this situation? Is it throwing an exception directly? Is it to keep the former and ignore the latter? Is it to ignore the former and keep the latter? Or does it allow a certain form of coexistence (such as the attributes of the latter overriding the former)?

Currently, the only configuration class type in dubbo and the configuration modes/strategies allowed by finding multiple instances of a unique configuration type are as follows.

Unique configuration class type

ApplicationConfig, MonitorConfig, MetricsConfig, SslConfig, ModuleConfig.

The first four belong to the application level, and the last one belongs to the module level.

configuration mode

strict: Strict mode. Throw an exception directly.
override: override mode. Ignore the former and keep the latter.
ignore: ignore pattern. Ignore the latter and keep the former.
override_all: attribute override mode. No matter whether the attribute value of the former is empty or not, the attribute of the latter is overwritten/set on the former.
override_if_absent: attribute override mode if absent. Only when the corresponding attribute value of the former is empty, can the attribute of the latter be overwritten/set on the former.

Note: The latter two also affect property overrides for configuration instances. Because dubbo has multiple configuration methods, that is, there are multiple configuration sources, and the configuration sources also have priorities. For example, a ServiceConfig is configured through xml and the attribute version=1.0.0 is specified. At the same time, we configure dubbo.service.{interface}.version=2.0.0 in the external configuration (configuration center), Before the config-mode configuration item is introduced, according to the original configuration source priority, version=2.0.0 of the final instance. However, after the config-mode configuration item is introduced, the configuration priority rules are no longer so strict, that is, if config-mode is override_all is specified, it is version=2.0.0, if config-mode is override_if_absent If it is version=1.0.0, if config-mode is other values, the property setting/overwriting will follow the original configuration priority.

Configuration method

The configured key is dubbo.config.mode, the configured values are as described above, and the default policy value is strict. A sample configuration is shown below

# JVM -D
-Ddubbo.config.mode=strict

# environment variables
DUBBO_CONFIG_MODE=strict

# External configuration (configuration center), Environment of Spring application, dubbo.properties
dubbo.config.mode=strict

Last modified July 20, 2023: Update properties.md (e516025bed)