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| <label for=m-enblognews-check><a href=/en/blog/news/ title="Articles About Apache Dubbo" class="align-left pl-0 td-sidebar-link td-sidebar-link__section" id=m-enblognews><span>Articles</span></a></label><ul class="ul-2 foldable"><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20240131tracing-dubbo-with-opentelemetry-li><input type=checkbox id=m-enblog20240131tracing-dubbo-with-opentelemetry-check> |
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| <label for=m-enblog20231023introduction-to-apache-dubbo-plugin-for-intellij-idea-check><a href=/en/blog/2023/10/23/introduction-to-apache-dubbo-plugin-for-intellij-idea/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20231023introduction-to-apache-dubbo-plugin-for-intellij-idea><span>Introduction to Apache Dubbo plugin for IntelliJ IDEA</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20230415advanced-cloud-native-dubbo-32-officially-released-li><input type=checkbox id=m-enblog20230415advanced-cloud-native-dubbo-32-officially-released-check> |
| <label for=m-enblog20230415advanced-cloud-native-dubbo-32-officially-released-check><a href=/en/blog/2023/04/15/advanced-cloud-native-dubbo-3.2-officially-released/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20230415advanced-cloud-native-dubbo-32-officially-released><span>Advanced cloud native - Dubbo 3.2 officially released</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20220504how-to-proxy-dubbo-service-in-apache-shenyu-gateway-li><input type=checkbox id=m-enblog20220504how-to-proxy-dubbo-service-in-apache-shenyu-gateway-check> |
| <label for=m-enblog20220504how-to-proxy-dubbo-service-in-apache-shenyu-gateway-check><a href=/en/blog/2022/05/04/how-to-proxy-dubbo-service-in-apache-shenyu-gateway/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20220504how-to-proxy-dubbo-service-in-apache-shenyu-gateway><span>How to proxy Dubbo service in Apache ShenYu Gateway</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20220118makes-it-more-convenient-for-you-to-proxy-dubbo-services-in-apache-apisix-li><input type=checkbox id=m-enblog20220118makes-it-more-convenient-for-you-to-proxy-dubbo-services-in-apache-apisix-check> |
| <label for=m-enblog20220118makes-it-more-convenient-for-you-to-proxy-dubbo-services-in-apache-apisix-check><a href=/en/blog/2022/01/18/makes-it-more-convenient-for-you-to-proxy-dubbo-services-in-apache-apisix/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20220118makes-it-more-convenient-for-you-to-proxy-dubbo-services-in-apache-apisix><span>Makes it More Convenient for You to Proxy Dubbo Services in Apache APISIX</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20190826service-test-li><input type=checkbox id=m-enblog20190826service-test-check> |
| <label for=m-enblog20190826service-test-check><a href=/en/blog/2019/08/26/service-test/ title="Dubbo Admin service test" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20190826service-test><span>Service test in dubbo admin</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20190811tracing-dubbo-service-with-apache-skywalking-li><input type=checkbox id=m-enblog20190811tracing-dubbo-service-with-apache-skywalking-check> |
| <label for=m-enblog20190811tracing-dubbo-service-with-apache-skywalking-check><a href=/en/blog/2019/08/11/tracing-dubbo-service-with-apache-skywalking/ title="Tracing Dubbo service with Apache Skywalking" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20190811tracing-dubbo-service-with-apache-skywalking><span>Use apache skywalking in dubbo</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20190502dubbo-extensible-mechanism-source-code-analysis-part-2-li><input type=checkbox id=m-enblog20190502dubbo-extensible-mechanism-source-code-analysis-part-2-check> |
| <label for=m-enblog20190502dubbo-extensible-mechanism-source-code-analysis-part-2-check><a href=/en/blog/2019/05/02/dubbo-extensible-mechanism-source-code-analysis-part-2/ title="Dubbo extensible mechanism source code analysis - part 2" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20190502dubbo-extensible-mechanism-source-code-analysis-part-2><span>Dubbo extensible mechanism - part 2</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20190425dubbo-extensible-mechanism-source-code-analysis-part-1-li><input type=checkbox id=m-enblog20190425dubbo-extensible-mechanism-source-code-analysis-part-1-check> |
| <label for=m-enblog20190425dubbo-extensible-mechanism-source-code-analysis-part-1-check><a href=/en/blog/2019/04/25/dubbo-extensible-mechanism-source-code-analysis-part-1/ title="Dubbo extensible mechanism source code analysis - part 1" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20190425dubbo-extensible-mechanism-source-code-analysis-part-1><span>Dubbo extensible mechanism - part 1</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20190220implementation-background-and-practice-of-dubbo-client-asynchronous-interface-li><input type=checkbox id=m-enblog20190220implementation-background-and-practice-of-dubbo-client-asynchronous-interface-check> |
| <label for=m-enblog20190220implementation-background-and-practice-of-dubbo-client-asynchronous-interface-check><a href=/en/blog/2019/02/20/implementation-background-and-practice-of-dubbo-client-asynchronous-interface/ title="Implementation background and practice of Dubbo client asynchronous interface" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20190220implementation-background-and-practice-of-dubbo-client-asynchronous-interface><span>Dubbo Async Client</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20190220implementation-background-and-practice-of-dubbo-server-asynchronous-interface-li><input type=checkbox id=m-enblog20190220implementation-background-and-practice-of-dubbo-server-asynchronous-interface-check> |
| <label for=m-enblog20190220implementation-background-and-practice-of-dubbo-server-asynchronous-interface-check><a href=/en/blog/2019/02/20/implementation-background-and-practice-of-dubbo-server-asynchronous-interface/ title="Implementation background and practice of Dubbo server asynchronous interface" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20190220implementation-background-and-practice-of-dubbo-server-asynchronous-interface><span>Dubbo Async Server</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20190117how-to-use-seata-to-ensure-consistency-between-dubbo-microservices-li><input type=checkbox id=m-enblog20190117how-to-use-seata-to-ensure-consistency-between-dubbo-microservices-check> |
| <label for=m-enblog20190117how-to-use-seata-to-ensure-consistency-between-dubbo-microservices-check><a href=/en/blog/2019/01/17/how-to-use-seata-to-ensure-consistency-between-dubbo-microservices/ title="How to use Seata to ensure consistency between Dubbo Microservices" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20190117how-to-use-seata-to-ensure-consistency-between-dubbo-microservices><span>Use Seata in Dubbo</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20181210the-fifth-dubbo-meetup-has-been-held-in-hangzhou-li><input type=checkbox id=m-enblog20181210the-fifth-dubbo-meetup-has-been-held-in-hangzhou-check> |
| <label for=m-enblog20181210the-fifth-dubbo-meetup-has-been-held-in-hangzhou-check><a href=/en/blog/2018/12/10/the-fifth-dubbo-meetup-has-been-held-in-hangzhou/ title="The fifth Dubbo meetup has been held in Hangzhou" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20181210the-fifth-dubbo-meetup-has-been-held-in-hangzhou><span>The fifth Dubbo meetup</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20181107dubbo-integrates-with-nacos-to-become-a-registry-li><input type=checkbox id=m-enblog20181107dubbo-integrates-with-nacos-to-become-a-registry-check> |
| <label for=m-enblog20181107dubbo-integrates-with-nacos-to-become-a-registry-check><a href=/en/blog/2018/11/07/dubbo-integrates-with-nacos-to-become-a-registry/ title="Dubbo Integrates with Nacos to Become a Registry" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20181107dubbo-integrates-with-nacos-to-become-a-registry><span>Use Dubbo with Nacos</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20181005introduction-to-the-dubbo-protocol-li><input type=checkbox id=m-enblog20181005introduction-to-the-dubbo-protocol-check> |
| <label for=m-enblog20181005introduction-to-the-dubbo-protocol-check><a href=/en/blog/2018/10/05/introduction-to-the-dubbo-protocol/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20181005introduction-to-the-dubbo-protocol><span>Introduction to the Dubbo protocol</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180930integrate-dubbo-with-kubernetes-li><input type=checkbox id=m-enblog20180930integrate-dubbo-with-kubernetes-check> |
| <label for=m-enblog20180930integrate-dubbo-with-kubernetes-check><a href=/en/blog/2018/09/30/integrate-dubbo-with-kubernetes/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180930integrate-dubbo-with-kubernetes><span>Integrate Dubbo with Kubernetes</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180902how-to-prepare-an-apache-release-li><input type=checkbox id=m-enblog20180902how-to-prepare-an-apache-release-check> |
| <label for=m-enblog20180902how-to-prepare-an-apache-release-check><a href=/en/blog/2018/09/02/how-to-prepare-an-apache-release/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180902how-to-prepare-an-apache-release><span>How to prepare an Apache Release</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180902how-to-implement-a-fully-asynchronous-calls-chain-based-on-dubbo-li><input type=checkbox id=m-enblog20180902how-to-implement-a-fully-asynchronous-calls-chain-based-on-dubbo-check> |
| <label for=m-enblog20180902how-to-implement-a-fully-asynchronous-calls-chain-based-on-dubbo-check><a href=/en/blog/2018/09/02/how-to-implement-a-fully-asynchronous-calls-chain-based-on-dubbo/ title="How to implement a fully asynchronous calls chain based on Dubbo" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180902how-to-implement-a-fully-asynchronous-calls-chain-based-on-dubbo><span>New Async Call</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180826the-fourth-dubbo-meetup-has-been-held-in-chengdu-li><input type=checkbox id=m-enblog20180826the-fourth-dubbo-meetup-has-been-held-in-chengdu-check> |
| <label for=m-enblog20180826the-fourth-dubbo-meetup-has-been-held-in-chengdu-check><a href=/en/blog/2018/08/26/the-fourth-dubbo-meetup-has-been-held-in-chengdu/ title="The fourth Dubbo meetup has been held in Chengdu" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180826the-fourth-dubbo-meetup-has-been-held-in-chengdu><span>The fourth Dubbo meetup</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180814dubbo-basic-usage-dubbo-consumer-configuration-li><input type=checkbox id=m-enblog20180814dubbo-basic-usage-dubbo-consumer-configuration-check> |
| <label for=m-enblog20180814dubbo-basic-usage-dubbo-consumer-configuration-check><a href=/en/blog/2018/08/14/dubbo-basic-usage-dubbo-consumer-configuration/ title=" Dubbo Basic Usage - Dubbo Consumer Configuration" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180814dubbo-basic-usage-dubbo-consumer-configuration><span>Dubbo Consumer Configuration</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180814dubbo-several-ways-about-synchronousasynchronous-invoke-li><input type=checkbox id=m-enblog20180814dubbo-several-ways-about-synchronousasynchronous-invoke-check> |
| <label for=m-enblog20180814dubbo-several-ways-about-synchronousasynchronous-invoke-check><a href=/en/blog/2018/08/14/dubbo-several-ways-about-synchronous/asynchronous-invoke/ title="Dubbo: Several ways about synchronous/asynchronous invoke" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180814dubbo-several-ways-about-synchronousasynchronous-invoke><span>Dubbo Invoke</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180814dubbo-basic-usage--dubbo-provider-configuration-li><input type=checkbox id=m-enblog20180814dubbo-basic-usage--dubbo-provider-configuration-check> |
| <label for=m-enblog20180814dubbo-basic-usage--dubbo-provider-configuration-check><a href=/en/blog/2018/08/14/dubbo-basic-usage--dubbo-provider-configuration/ title="Dubbo Basic Usage -- Dubbo Provider Configuration" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180814dubbo-basic-usage--dubbo-provider-configuration><span>Dubbo Provider Configuration</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180814manipulating-services-dynamically-via-qos-li><input type=checkbox id=m-enblog20180814manipulating-services-dynamically-via-qos-check> |
| <label for=m-enblog20180814manipulating-services-dynamically-via-qos-check><a href=/en/blog/2018/08/14/manipulating-services-dynamically-via-qos/ title="Manipulating Services Dynamically via QoS" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180814manipulating-services-dynamically-via-qos><span>Dubbo QoS Introduction</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180814source-code-analysis-of-spring-boot-dubbo-app-start-and-stop-li><input type=checkbox id=m-enblog20180814source-code-analysis-of-spring-boot-dubbo-app-start-and-stop-check> |
| <label for=m-enblog20180814source-code-analysis-of-spring-boot-dubbo-app-start-and-stop-check><a href=/en/blog/2018/08/14/source-code-analysis-of-spring-boot-dubbo-app-start-and-stop/ title="Source code analysis of spring-boot+Dubbo App start and stop" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180814source-code-analysis-of-spring-boot-dubbo-app-start-and-stop><span>Dubbo start/stop in spring boot</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180814implementation-of-cross-language-calls-by-dubbo2js-li><input type=checkbox id=m-enblog20180814implementation-of-cross-language-calls-by-dubbo2js-check> |
| <label for=m-enblog20180814implementation-of-cross-language-calls-by-dubbo2js-check><a href=/en/blog/2018/08/14/implementation-of-cross-language-calls-by-dubbo2.js/ title="Implementation of cross-language calls by Dubbo2.js" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180814implementation-of-cross-language-calls-by-dubbo2js><span>dubbo2.js introduction</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180814generic-invoke-of-dubbo-li><input type=checkbox id=m-enblog20180814generic-invoke-of-dubbo-check> |
| <label for=m-enblog20180814generic-invoke-of-dubbo-check><a href=/en/blog/2018/08/14/generic-invoke-of-dubbo/ title="Generic invoke of Dubbo" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180814generic-invoke-of-dubbo><span>Generic invoke</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180814native-image-using-graalvm-li><input type=checkbox id=m-enblog20180814native-image-using-graalvm-check> |
| <label for=m-enblog20180814native-image-using-graalvm-check><a href=/en/blog/2018/08/14/native-image-using-graalvm/ title="Native Image using GraalVM" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180814native-image-using-graalvm><span>Native Image</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180810dubbos-load-balance-li><input type=checkbox id=m-enblog20180810dubbos-load-balance-check> |
| <label for=m-enblog20180810dubbos-load-balance-check><a href=/en/blog/2018/08/10/dubbos-load-balance/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180810dubbos-load-balance><span>Dubbo's Load Balance</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180807use-annotations-in-dubbo-li><input type=checkbox id=m-enblog20180807use-annotations-in-dubbo-check> |
| <label for=m-enblog20180807use-annotations-in-dubbo-check><a href=/en/blog/2018/08/07/use-annotations-in-dubbo/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180807use-annotations-in-dubbo><span>Use Annotations In Dubbo</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180807using-zookeeper-in-dubbo-li><input type=checkbox id=m-enblog20180807using-zookeeper-in-dubbo-check> |
| <label for=m-enblog20180807using-zookeeper-in-dubbo-check><a href=/en/blog/2018/08/07/using-zookeeper-in-dubbo/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180807using-zookeeper-in-dubbo><span>Using Zookeeper in Dubbo</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180807dubbo-101-li><input type=checkbox id=m-enblog20180807dubbo-101-check> |
| <label for=m-enblog20180807dubbo-101-check><a href=/en/blog/2018/08/07/dubbo-101/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180807dubbo-101><span>Your First Dubbo Demo</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180730the-third-dubbo-meetup-has-been-held-in-shenzhen-li><input type=checkbox id=m-enblog20180730the-third-dubbo-meetup-has-been-held-in-shenzhen-check> |
| <label for=m-enblog20180730the-third-dubbo-meetup-has-been-held-in-shenzhen-check><a href=/en/blog/2018/07/30/the-third-dubbo-meetup-has-been-held-in-shenzhen/ title="The third Dubbo meetup has been held in Shenzhen" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180730the-third-dubbo-meetup-has-been-held-in-shenzhen><span>The third Dubbo meetup</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180727sentinel-the-flow-sentinel-of-dubbo-services-li><input type=checkbox id=m-enblog20180727sentinel-the-flow-sentinel-of-dubbo-services-check> |
| <label for=m-enblog20180727sentinel-the-flow-sentinel-of-dubbo-services-check><a href=/en/blog/2018/07/27/sentinel-the-flow-sentinel-of-dubbo-services/ title="Sentinel: The flow sentinel of Dubbo services" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180727sentinel-the-flow-sentinel-of-dubbo-services><span>Introduce sentinel</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180712tracking-with-pinpoint-li><input type=checkbox id=m-enblog20180712tracking-with-pinpoint-check> |
| <label for=m-enblog20180712tracking-with-pinpoint-check><a href=/en/blog/2018/07/12/tracking-with-pinpoint/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180712tracking-with-pinpoint><span>Tracking with Pinpoint</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180701your-first-dubbo-filter-li><input type=checkbox id=m-enblog20180701your-first-dubbo-filter-check> |
| <label for=m-enblog20180701your-first-dubbo-filter-check><a href=/en/blog/2018/07/01/your-first-dubbo-filter/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180701your-first-dubbo-filter><span>Your First Dubbo Filter</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180623the-second-dubbo-shanghai-meetup-has-been-held-successfully-li><input type=checkbox id=m-enblog20180623the-second-dubbo-shanghai-meetup-has-been-held-successfully-check> |
| <label for=m-enblog20180623the-second-dubbo-shanghai-meetup-has-been-held-successfully-check><a href=/en/blog/2018/06/23/the-second-dubbo-shanghai-meetup-has-been-held-successfully/ title="The second Dubbo Shanghai meetup has been held successfully" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180623the-second-dubbo-shanghai-meetup-has-been-held-successfully><span>The second Dubbo meetup</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180512the-first-dubbo-meetup-has-been-held-in-beijing-li><input type=checkbox id=m-enblog20180512the-first-dubbo-meetup-has-been-held-in-beijing-check> |
| <label for=m-enblog20180512the-first-dubbo-meetup-has-been-held-in-beijing-check><a href=/en/blog/2018/05/12/the-first-dubbo-meetup-has-been-held-in-beijing/ title="The first Dubbo meetup has been held in Beijing" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180512the-first-dubbo-meetup-has-been-held-in-beijing><span>The first Dubbo meetup</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180502the-apachecon-na-schedule-has-been-announced-li><input type=checkbox id=m-enblog20180502the-apachecon-na-schedule-has-been-announced-check> |
| <label for=m-enblog20180502the-apachecon-na-schedule-has-been-announced-check><a href=/en/blog/2018/05/02/the-apachecon-na-schedule-has-been-announced/ title="The ApacheCon NA schedule has been announced" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180502the-apachecon-na-schedule-has-been-announced><span>ApacheCon NA</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180425the-gsocgoogle-summer-of-code-2018-li><input type=checkbox id=m-enblog20180425the-gsocgoogle-summer-of-code-2018-check> |
| <label for=m-enblog20180425the-gsocgoogle-summer-of-code-2018-check><a href=/en/blog/2018/04/25/the-gsocgoogle-summer-of-code-2018/ title="The GSoC(Google Summer of Code) 2018" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180425the-gsocgoogle-summer-of-code-2018><span>GSoC 2018</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20180422dubbo-roadmap-is-announced-in-qcon-beijing-2018-li><input type=checkbox id=m-enblog20180422dubbo-roadmap-is-announced-in-qcon-beijing-2018-check> |
| <label for=m-enblog20180422dubbo-roadmap-is-announced-in-qcon-beijing-2018-check><a href=/en/blog/2018/04/22/dubbo-roadmap-is-announced-in-qcon-beijing-2018/ title="Dubbo roadmap is announced in QCon Beijing 2018" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20180422dubbo-roadmap-is-announced-in-qcon-beijing-2018><span>QCon Beijing 2018</span></a></label></li></ul></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section with-child" id=m-enblogproposals-li><input type=checkbox id=m-enblogproposals-check> |
| <label for=m-enblogproposals-check><a href=/en/blog/proposals/ title="Proposals About Apache Dubbo" class="align-left pl-0 td-sidebar-link td-sidebar-link__section" id=m-enblogproposals><span>Proposals</span></a></label><ul class="ul-2 foldable"><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog10101application-level-service-discovery-li><input type=checkbox id=m-enblog10101application-level-service-discovery-check> |
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| <label for=m-enblog10101enhanced-http-standard-capabilities-of-triple-protocol-check><a href=/en/blog/1/01/01/enhanced-http-standard-capabilities-of-triple-protocol/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog10101enhanced-http-standard-capabilities-of-triple-protocol><span>Enhanced HTTP Standard Capabilities of Triple Protocol</span></a></label></li></ul></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section with-child" id=m-enblogreleases-li><input type=checkbox id=m-enblogreleases-check> |
| <label for=m-enblogreleases-check><a href=/en/blog/releases/ title="New Releases" class="align-left pl-0 td-sidebar-link td-sidebar-link__section" id=m-enblogreleases><span>Releases</span></a></label><ul class="ul-2 foldable"><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog202109202714-release-note-li><input type=checkbox id=m-enblog202109202714-release-note-check> |
| <label for=m-enblog202109202714-release-note-check><a href=/en/blog/2021/09/20/2.7.14-release-note/ title="2.7.14 Release Note" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog202109202714-release-note><span>2.7.14</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog202108233021-release-note-li><input type=checkbox id=m-enblog202108233021-release-note-check> |
| <label for=m-enblog202108233021-release-note-check><a href=/en/blog/2021/08/23/3.0.2.1-release-note/ title="3.0.2.1 Release Note" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog202108233021-release-note><span>3.0.2.1</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20210818302-release-note-li><input type=checkbox id=m-enblog20210818302-release-note-check> |
| <label for=m-enblog20210818302-release-note-check><a href=/en/blog/2021/08/18/3.0.2-release-note/ title="3.0.2 Release Note" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20210818302-release-note><span>3.0.2</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20210702301-release-note-li><input type=checkbox id=m-enblog20210702301-release-note-check> |
| <label for=m-enblog20210702301-release-note-check><a href=/en/blog/2021/07/02/3.0.1-release-note/ title="3.0.1 Release Note" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20210702301-release-note><span>3.0.1</span></a></label></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-enblog20200518past-releases-li><input type=checkbox id=m-enblog20200518past-releases-check> |
| <label for=m-enblog20200518past-releases-check><a href=/en/blog/2020/05/18/past-releases/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-enblog20200518past-releases><span>Past Releases</span></a></label></li></ul></li></ul></li></ul></nav></div></div><main class="col-12 col-md-9 col-xl-8 pl-md-5" role=main><nav aria-label=breadcrumb class=td-breadcrumbs><ol class=breadcrumb><li class=breadcrumb-item><a href=https://cn.dubbo.apache.org/en/blog/>Blog</a></li><li class=breadcrumb-item><a href=https://cn.dubbo.apache.org/en/blog/news/>Articles</a></li><li class="breadcrumb-item active" aria-current=page><a href=https://cn.dubbo.apache.org/en/blog/2018/07/01/your-first-dubbo-filter/ aria-disabled=true class="btn-link disabled">Your First Dubbo Filter</a></li></ol></nav><section id=deprecation-warning><div class="content deprecation-warning pageinfo outdated-blog"><p>This article is more than one year old. Older articles may contain outdated content. Check that the information in the page has not become incorrect since its publication.</p></div></section><div class=td-content><h1>Your First Dubbo Filter</h1><div class=lead>This article will introduce you that how to implement a dubbo filter</div><div class="td-byline mb-4"><time datetime=2018-07-01 class=text-muted>Sunday, July 01, 2018</time></div><header class=article-meta></header><h3 id=overview>Overview</h3><p>In overall design of Dubbo, Filter is a very important concept, most of Dubbo’s functions are based on this |
| extension point, and the Filter interception will be executed during each call.</p><h4 id=extension-mechanism-of-dubbo-filter>Extension Mechanism of Dubbo Filter</h4><p>There are already about 20 Filters implemented in Dubbo. Their entry is ProtocolFilterWrapper, ProtocolFilterWrapper |
| makes a Wrapper on Protocol and will be loaded when the extension is loaded. Then, let’s see how |
| the Filter chain is constructed.</p><div class=highlight><pre tabindex=0 style=color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4><code class=language-java data-lang=java><span style=display:flex><span><span style=color:#586e75>//ProtocolFilterWrapper.java</span> |
| </span></span><span style=display:flex><span><span style=color:#268bd2>public</span> <span style=color:#719e07><</span>T<span style=color:#719e07>></span> Invoker<span style=color:#719e07><</span>T<span style=color:#719e07>></span> <span style=color:#268bd2>refer</span>(Class<span style=color:#719e07><</span>T<span style=color:#719e07>></span> type, URL url) <span style=color:#268bd2>throws</span> RpcException { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (Constants.REGISTRY_PROTOCOL.equals(url.getProtocol())) { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> protocol.refer(type, url); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> buildInvokerChain(protocol.refer(type, url), Constants.REFERENCE_FILTER_KEY, Constants.CONSUMER); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>private</span> <span style=color:#268bd2>static</span> <span style=color:#719e07><</span>T<span style=color:#719e07>></span> Invoker<span style=color:#719e07><</span>T<span style=color:#719e07>></span> <span style=color:#268bd2>buildInvokerChain</span>(<span style=color:#268bd2>final</span> Invoker<span style=color:#719e07><</span>T<span style=color:#719e07>></span> invoker, String key, String group) { |
| </span></span><span style=display:flex><span> Invoker<span style=color:#719e07><</span>T<span style=color:#719e07>></span> last <span style=color:#719e07>=</span> invoker; |
| </span></span><span style=display:flex><span> List<span style=color:#719e07><</span>Filter<span style=color:#719e07>></span> filters <span style=color:#719e07>=</span> ExtensionLoader.getExtensionLoader(Filter.class).getActivateExtension(invoker.getUrl(), key, group); |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (filters.size() <span style=color:#719e07>></span> 0) { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>for</span> (<span style=color:#dc322f>int</span> i <span style=color:#719e07>=</span> filters.size() <span style=color:#719e07>-</span> 1; i <span style=color:#719e07>>=</span> 0; i <span style=color:#719e07>--</span>) { |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>final</span> Filter filter <span style=color:#719e07>=</span> filters.get(i); |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>final</span> Invoker<span style=color:#719e07><</span>T<span style=color:#719e07>></span> next <span style=color:#719e07>=</span> last; |
| </span></span><span style=display:flex><span> last <span style=color:#719e07>=</span> <span style=color:#719e07>new</span> Invoker<span style=color:#719e07><</span>T<span style=color:#719e07>></span>() { |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>public</span> Class<span style=color:#719e07><</span>T<span style=color:#719e07>></span> <span style=color:#268bd2>getInterface</span>() { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> invoker.getInterface(); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>public</span> URL <span style=color:#268bd2>getUrl</span>() { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> invoker.getUrl(); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>public</span> <span style=color:#dc322f>boolean</span> <span style=color:#268bd2>isAvailable</span>() { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> invoker.isAvailable(); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>public</span> Result <span style=color:#268bd2>invoke</span>(Invocation invocation) <span style=color:#268bd2>throws</span> RpcException { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> filter.invoke(next, invocation); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>public</span> <span style=color:#dc322f>void</span> <span style=color:#268bd2>destroy</span>() { |
| </span></span><span style=display:flex><span> invoker.destroy(); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>@Override</span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>public</span> String <span style=color:#268bd2>toString</span>() { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> invoker.toString(); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> }; |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> last; |
| </span></span><span style=display:flex><span> } |
| </span></span></code></pre></div><h4 id=activation-mechanism-of-dubbo-filter>Activation Mechanism of Dubbo Filter</h4><p>Through the above code we can see that, in the method buildInvokerChain, first get all |
| activated chains, the chain here is already sorted. Then construct a call chain of Filter |
| through the Invoker, finally the constructed call chain can be roughly expressed as: Filter1->Filter2->Filter3->……->Invoker, |
| now let’s see the detailed flow of the activated chain in the above step.</p><div class=highlight><pre tabindex=0 style=color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4><code class=language-java data-lang=java><span style=display:flex><span> <span style=color:#268bd2>public</span> List<span style=color:#719e07><</span>T<span style=color:#719e07>></span> <span style=color:#268bd2>getActivateExtension</span>(URL url, String key, String group) { |
| </span></span><span style=display:flex><span> String value <span style=color:#719e07>=</span> url.getParameter(key); |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> getActivateExtension(url, value <span style=color:#719e07>==</span> <span style=color:#cb4b16>null</span> <span style=color:#719e07>||</span> value.length() <span style=color:#719e07>==</span> 0 <span style=color:#719e07>?</span> <span style=color:#cb4b16>null</span> : Constants.COMMA_SPLIT_PATTERN.split(value), group); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>public</span> List<span style=color:#719e07><</span>T<span style=color:#719e07>></span> <span style=color:#268bd2>getActivateExtension</span>(URL url, String<span style=color:#719e07>[]</span> values, String group) { |
| </span></span><span style=display:flex><span> List<span style=color:#719e07><</span>T<span style=color:#719e07>></span> exts <span style=color:#719e07>=</span> <span style=color:#719e07>new</span> ArrayList<span style=color:#719e07><</span>T<span style=color:#719e07>></span>(); |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> List<span style=color:#719e07><</span>String<span style=color:#719e07>></span> names <span style=color:#719e07>=</span> values <span style=color:#719e07>==</span> <span style=color:#cb4b16>null</span> <span style=color:#719e07>?</span> <span style=color:#719e07>new</span> ArrayList<span style=color:#719e07><</span>String<span style=color:#719e07>></span>(0) : Arrays.asList(values); |
| </span></span><span style=display:flex><span> |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (<span style=color:#719e07>!</span> names.contains(Constants.REMOVE_VALUE_PREFIX <span style=color:#719e07>+</span> Constants.DEFAULT_KEY)) { |
| </span></span><span style=display:flex><span> getExtensionClasses(); |
| </span></span><span style=display:flex><span> <span style=color:#719e07>for</span> (Map.Entry<span style=color:#719e07><</span>String, Activate<span style=color:#719e07>></span> entry : cachedActivates.entrySet()) { |
| </span></span><span style=display:flex><span> String name <span style=color:#719e07>=</span> entry.getKey(); |
| </span></span><span style=display:flex><span> Activate activate <span style=color:#719e07>=</span> entry.getValue(); |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (isMatchGroup(group, activate.group())) { |
| </span></span><span style=display:flex><span> T ext <span style=color:#719e07>=</span> getExtension(name); |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (<span style=color:#719e07>!</span> names.contains(name) <span style=color:#719e07>&&</span> <span style=color:#719e07>!</span> names.contains(Constants.REMOVE_VALUE_PREFIX <span style=color:#719e07>+</span> name) |
| </span></span><span style=display:flex><span> <span style=color:#719e07>&&</span> isActive(activate, url)) { |
| </span></span><span style=display:flex><span> exts.add(ext); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> Collections.sort(exts, ActivateComparator.COMPARATOR); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> List<span style=color:#719e07><</span>T<span style=color:#719e07>></span> usrs <span style=color:#719e07>=</span> <span style=color:#719e07>new</span> ArrayList<span style=color:#719e07><</span>T<span style=color:#719e07>></span>(); |
| </span></span><span style=display:flex><span> <span style=color:#719e07>for</span> (<span style=color:#dc322f>int</span> i <span style=color:#719e07>=</span> 0; i <span style=color:#719e07><</span> names.size(); i <span style=color:#719e07>++</span>) { |
| </span></span><span style=display:flex><span> String name <span style=color:#719e07>=</span> names.get(i); |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (<span style=color:#719e07>!</span> name.startsWith(Constants.REMOVE_VALUE_PREFIX) |
| </span></span><span style=display:flex><span> <span style=color:#719e07>&&</span> <span style=color:#719e07>!</span> names.contains(Constants.REMOVE_VALUE_PREFIX <span style=color:#719e07>+</span> name)) { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (Constants.DEFAULT_KEY.equals(name)) { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (usrs.size() <span style=color:#719e07>></span> 0) { |
| </span></span><span style=display:flex><span> exts.addAll(0, usrs); |
| </span></span><span style=display:flex><span> usrs.clear(); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> } <span style=color:#719e07>else</span> { |
| </span></span><span style=display:flex><span> T ext <span style=color:#719e07>=</span> getExtension(name); |
| </span></span><span style=display:flex><span> usrs.add(ext); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (usrs.size() <span style=color:#719e07>></span> 0) { |
| </span></span><span style=display:flex><span> exts.addAll(usrs); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> exts; |
| </span></span><span style=display:flex><span> } |
| </span></span></code></pre></div><p>Through the above code we can see that, some of the Filters configured by the user are activated by default, |
| and some need to be activated by the configuration file. The loading order of all Filters is to process Dubbo’s |
| default Filter first, and then to process the Filter defined by the user. With the “-” configuration, Dubbo’s defualt Filter |
| can be replaced, with this configuration, the user can flexibly replace or modify the Filter’s load order.</p><h4 id=built-in-filter-of-dubbo>Built-in Filter of Dubbo</h4><p>Dubbo has lots of built-in Filter. RpcContext, accesslog and other functions can be implemented by Dubbo. |
| Now let’s see the ConsumerContextFilter which used by the Consumer side for context delivery:</p><div class=highlight><pre tabindex=0 style=color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4><code class=language-java data-lang=java><span style=display:flex><span><span style=color:#268bd2>public</span> Result <span style=color:#268bd2>invoke</span>(Invoker<span style=color:#719e07><?></span> invoker, Invocation invocation) <span style=color:#268bd2>throws</span> RpcException { |
| </span></span><span style=display:flex><span> RpcContext.getContext() |
| </span></span><span style=display:flex><span> .setInvoker(invoker) |
| </span></span><span style=display:flex><span> .setInvocation(invocation) |
| </span></span><span style=display:flex><span> .setLocalAddress(NetUtils.getLocalHost(), 0) |
| </span></span><span style=display:flex><span> .setRemoteAddress(invoker.getUrl().getHost(), |
| </span></span><span style=display:flex><span> invoker.getUrl().getPort()); |
| </span></span><span style=display:flex><span> <span style=color:#719e07>if</span> (invocation <span style=color:#719e07>instanceof</span> RpcInvocation) { |
| </span></span><span style=display:flex><span> ((RpcInvocation)invocation).setInvoker(invoker); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> <span style=color:#719e07>try</span> { |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> invoker.invoke(invocation); |
| </span></span><span style=display:flex><span> } <span style=color:#719e07>finally</span> { |
| </span></span><span style=display:flex><span> RpcContext.getContext().clearAttachments(); |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span> } |
| </span></span></code></pre></div><p>This Filter records the state information during call, and passes the attachments parameter set |
| by the client to the server through the invocation object, and these parameters will be cleared |
| after the call is completed, which is why the request status information can be recorded by times |
| and delivered.</p><h4 id=implement-a-dubbo-filter>Implement A Dubbo Filter</h4><p>Because of Dubbo’s flexible design and good scalability, we can implement business logic |
| in the call chain by implementing our own Dubbo Filter, such as time-consuming statistics, monitor information statistics, etc. |
| Now, let’s implement a simple Filter:</p><p>Maven project structure:</p><div class=highlight><pre tabindex=0 style=color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4><code class=language-fallback data-lang=fallback><span style=display:flex><span>src |
| </span></span><span style=display:flex><span> |-main |
| </span></span><span style=display:flex><span> |-java |
| </span></span><span style=display:flex><span> |-com |
| </span></span><span style=display:flex><span> |-xxx |
| </span></span><span style=display:flex><span> |-XxxFilter.java (impelement Filter interface) |
| </span></span><span style=display:flex><span> |-resources |
| </span></span><span style=display:flex><span> |-META-INF |
| </span></span><span style=display:flex><span> |-dubbo |
| </span></span><span style=display:flex><span> |-com.alibaba.dubbo.rpc.Filter (Plain text file with content：xxx=com.xxx.XxxFilter) |
| </span></span></code></pre></div><p>XxxFilter.java：</p><div class=highlight><pre tabindex=0 style=color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4><code class=language-java data-lang=java><span style=display:flex><span><span style=color:#268bd2>public</span> <span style=color:#268bd2>class</span> <span style=color:#268bd2>XxxFilter</span> <span style=color:#268bd2>implements</span> Filter { |
| </span></span><span style=display:flex><span> <span style=color:#268bd2>public</span> Result <span style=color:#268bd2>invoke</span>(Invoker<span style=color:#719e07><?></span> invoker, Invocation invocation) <span style=color:#268bd2>throws</span> RpcException { |
| </span></span><span style=display:flex><span> <span style=color:#586e75>// before filter ...</span> |
| </span></span><span style=display:flex><span> Result result <span style=color:#719e07>=</span> invoker.invoke(invocation); |
| </span></span><span style=display:flex><span> <span style=color:#586e75>// after filter ...</span> |
| </span></span><span style=display:flex><span> <span style=color:#719e07>return</span> result; |
| </span></span><span style=display:flex><span> } |
| </span></span><span style=display:flex><span>} |
| </span></span></code></pre></div><p>META-INF/dubbo/com.alibaba.dubbo.rpc.Filter：</p><div class=highlight><pre tabindex=0 style=color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4><code class=language-fallback data-lang=fallback><span style=display:flex><span>xxx=com.xxx.XxxFilter |
| </span></span></code></pre></div><p>configure in xml as:</p><div class=highlight><pre tabindex=0 style=color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4><code class=language-xml data-lang=xml><span style=display:flex><span><span style=color:#586e75><!-- Consumer call process interception --></span> |
| </span></span><span style=display:flex><span><span style=color:#268bd2><dubbo:reference</span> filter=<span style=color:#2aa198>"xxx"</span> <span style=color:#268bd2>/></span> |
| </span></span><span style=display:flex><span><span style=color:#586e75><!-- Consumer call process default interception，intercept all reference --></span> |
| </span></span><span style=display:flex><span><span style=color:#268bd2><dubbo:consumer</span> filter=<span style=color:#2aa198>"xxx"</span><span style=color:#268bd2>/></span> |
| </span></span><span style=display:flex><span><span style=color:#586e75><!-- Provider call process interception --></span> |
| </span></span><span style=display:flex><span><span style=color:#268bd2><dubbo:service</span> filter=<span style=color:#2aa198>"xxx"</span> <span style=color:#268bd2>/></span> |
| </span></span><span style=display:flex><span><span style=color:#586e75><!-- Provider call process default interception，intercept all service --></span> |
| </span></span><span style=display:flex><span><span style=color:#268bd2><dubbo:provider</span> filter=<span style=color:#2aa198>"xxx"</span><span style=color:#268bd2>/></span> |
| </span></span></code></pre></div><p>or use annotation as:</p><div class=highlight><pre tabindex=0 style=color:#93a1a1;background-color:#002b36;-moz-tab-size:4;-o-tab-size:4;tab-size:4><code class=language-java data-lang=java><span style=display:flex><span><span style=color:#268bd2>@Activate</span>(group <span style=color:#719e07>=</span> <span style=color:#2aa198>"consumer"</span>) |
| </span></span><span style=display:flex><span><span style=color:#268bd2>public</span> <span style=color:#268bd2>class</span> <span style=color:#268bd2>XxxFilter</span> <span style=color:#268bd2>implements</span> Filter { |
| </span></span><span style=display:flex><span> <span style=color:#586e75>// ...</span> |
| </span></span><span style=display:flex><span>} |
| </span></span></code></pre></div><p>Using xml configuration is more flexible and granular.</p><p>In before and after, you can implement your own business logic to give the filter a certain function. |
| Once written and configured, the filter is activated by the Dubbo and executed in the call chain.</p><ul class="list-unstyled d-flex justify-content-between align-items-center mb-0 pt-5"><li><a href=/en/blog/2018/06/23/the-second-dubbo-shanghai-meetup-has-been-held-successfully/ aria-label="Previous - The second Dubbo Shanghai meetup has been held successfully" class="btn btn-primary"><span class=mr-1>←</span>Previous</a></li><li><a href=/en/blog/2018/07/12/tracking-with-pinpoint/ aria-label="Next - Tracking with Pinpoint" class="btn btn-primary">Next<span class=ml-1>→</span></a></li></ul></div><div id=pre-footer><h2>Feedback</h2><p class=feedback--prompt>Was this page helpful?</p><button class="btn btn-primary mb-4 feedback--yes">Yes</button> |
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