Add Spring WebFlux and WebClient tracing. (#95)

Author: csabakos

.settings.xml

@@ -1,4 +1,19 @@
 <?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+    Copyright 2016-2019 The OpenTracing Authors
+
+    Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+    in compliance with the License. You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software distributed under the License
+    is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+    or implied. See the License for the specific language governing permissions and limitations under
+    the License.
+
+-->
 <settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0

README.md

@@ -2,22 +2,32 @@
 
 # OpenTracing Spring Web Instrumentation
 
-This library provides instrumentation for Spring  Web applications (Boot and MVC). It creates tracing data for 
-server requests and also client requests (`RestTemplate` and `AsyncRestTemplate`).
+This library provides instrumentation for Spring Web applications (Boot, MVC and WebFlux). It creates tracing data for 
+server requests and also client requests (`RestTemplate`, `AsyncRestTemplate` and `WebClient`).
 
 ## Use [opentracing-spring-cloud](https://github.com/opentracing-contrib/java-spring-cloud) instead
 
 As it was mentioned above this library traces only inbound/outbound HTTP requests. If you would like to 
 get automatically traced different set of technologies e.g. `spring-cloud-netflix`, JMS or even more then
 use project [opentracing-spring-cloud](https://github.com/opentracing-contrib/java-spring-cloud) instead.
 
+For reactive applications, it is especially recommended to use `reactor` tracing from
+[opentracing-spring-cloud](https://github.com/opentracing-contrib/java-spring-cloud), as that will ensure
+that the `Span` is activated in reactor handler functions. (Without that, one would have to extract the
+`Span` from the subscriber context.)
+
 ## How does the server tracing work?
 
+### Servlet
 Server span is started in [Web Servlet Filter](https://github.com/opentracing-contrib/java-web-servlet-filter),
 then tracing interceptor adds spring related tags and logs. There are use case when spring boot invokes a handler after 
 a request processing in filter finished, in this case interceptor starts a new span as `followsFrom` 
 which references the initial span created in the servlet filter.
 
+### Reactive
+Server span is started in [TracingWebFilter](opentracing-spring-web/src/main/java/io/opentracing/contrib/spring/web/webfilter/TracingWebFilter.java)
+(upon subscription), then `onNext()`, `onError()`, etc. handlers add Spring WebFlux related tags and logs.
+
 ## Library versions
 
 Versions 1.x.y of the library are meant to target Spring Framework 5.x and Spring Boot 2.x while versions 0.x.y are meant to be used with Spring Framework 4.3 and Spring Boot 1.5
@@ -36,11 +46,11 @@ If you are using Spring Boot the easiest way how to configure OpenTracing instru
 
 ```
 Just provide an OpenTracing tracer bean and all required configuration is automatically
-done for you. It also instruments all `RestTemplate` and `AsyncRestTemplate` beans.
+done for you. It also instruments all `RestTemplate`, `AsyncRestTemplate`, `WebClient` and `WebClient.Builder` beans.
 
 ### Manual configuration
 
-#### Server
+#### Servlet and MVC Server
 Configuration needs to add `TracingFilter` and `TracingHandlerInterceptor`. Both of these classes
 are required!
 
@@ -77,6 +87,25 @@ public class MVCConfiguration extends WebMvcConfigurerAdapter {
 
 XML based configuration can be used too. Filter can be also directly defined in `web.xml`.
 
+#### Reactive Server
+Configuration needs to add the `TracingWebFilter` bean.
+
+```java
+@Configuration
+class TracingConfiguration {
+    @Bean
+    public TracingWebFilter tracingWebFilter(Tracer tracer) {
+        return new TracingWebFilter(
+                tracer,
+                Integer.MIN_VALUE,               // Order
+                Pattern.compile(""),             // Skip pattern
+                Collections.singletonList("/*"), // URL patterns
+                Arrays.asList(new WebFluxSpanDecorator.StandardTags(), new WebFluxSpanDecorator.WebFluxTags())
+        );
+    }
+}
+```
+
 #### Client
 ```java
 RestTemplate restTemplate = new RestTemplate();
@@ -85,6 +114,13 @@ restTemplate.setInterceptors(Collections.singletonList(new TracingRestTemplateIn
 // the same applies for AsyncRestTemplate 
 ```
 
+#### Reactive Client
+```java
+WebClient webClient = WebClient.builder()
+        .filter(new TracingExchangeFilterFunction(tracer, Collections.singletonList(new WebClientSpanDecorator.StandardTags())))
+        .build();
+```
+
 ## Access server span
 ```java
 @RequestMapping("/hello")

header.txt

@@ -0,0 +1,11 @@
+Copyright ${license.git.copyrightYears} The OpenTracing Authors
+
+Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+in compliance with the License. You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software distributed under the License
+is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+or implied. See the License for the specific language governing permissions and limitations under
+the License.

opentracing-spring-web-itest/boot/pom.xml

@@ -1,4 +1,19 @@
 <?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+    Copyright 2016-2019 The OpenTracing Authors
+
+    Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+    in compliance with the License. You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software distributed under the License
+    is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+    or implied. See the License for the specific language governing permissions and limitations under
+    the License.
+
+-->
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
@@ -9,6 +24,10 @@
 
   <artifactId>opentracing-spring-web-itest-boot</artifactId>
 
+  <properties>
+    <main.basedir>${project.basedir}/../..</main.basedir>
+  </properties>
+
   <dependencies>
     <dependency>
       <groupId>${project.groupId}</groupId>

opentracing-spring-web-itest/boot/src/main/webapp/WEB-INF/jsp/staticView.jsp

@@ -1,3 +1,18 @@
+<%--
+
+    Copyright 2016-2019 The OpenTracing Authors
+
+    Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+    in compliance with the License. You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software distributed under the License
+    is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+    or implied. See the License for the specific language governing permissions and limitations under
+    the License.
+
+--%>
 <!DOCTYPE html>
 <body/>
 </html>

opentracing-spring-web-itest/boot/src/test/java/io/opentracing/contrib/spring/web/interceptor/itest/boot/BootITest.java

@@ -1,3 +1,16 @@
+/**
+ * Copyright 2016-2019 The OpenTracing Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
 package io.opentracing.contrib.spring.web.interceptor.itest.boot;
 
 import org.junit.runner.RunWith;

opentracing-spring-web-itest/boot/src/test/java/io/opentracing/contrib/spring/web/interceptor/itest/boot/SpringBootConfiguration.java

@@ -1,3 +1,16 @@
+/**
+ * Copyright 2016-2019 The OpenTracing Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
 package io.opentracing.contrib.spring.web.interceptor.itest.boot;
 
 import java.util.Collections;

opentracing-spring-web-itest/boot/src/test/resources/application.properties

@@ -1,2 +1,16 @@
+#
+# Copyright 2016-2019 The OpenTracing Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+# in compliance with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software distributed under the License
+# is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+# or implied. See the License for the specific language governing permissions and limitations under
+# the License.
+#
+
 spring.mvc.view.prefix: WEB-INF/jsp/
 spring.mvc.view.suffix: .jsp

opentracing-spring-web-itest/common/pom.xml

@@ -1,4 +1,19 @@
 <?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+    Copyright 2016-2019 The OpenTracing Authors
+
+    Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+    in compliance with the License. You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software distributed under the License
+    is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+    or implied. See the License for the specific language governing permissions and limitations under
+    the License.
+
+-->
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
@@ -9,6 +24,10 @@
 
   <artifactId>opentracing-spring-web-itest-common</artifactId>
 
+  <properties>
+    <main.basedir>${project.basedir}/../..</main.basedir>
+  </properties>
+
   <dependencies>
     <dependency>
       <groupId>${project.groupId}</groupId>

opentracing-spring-web-itest/common/src/test/java/io/opentracing/contrib/spring/web/interceptor/itest/common/AbstractBaseITests.java

@@ -1,3 +1,16 @@
+/**
+ * Copyright 2016-2019 The OpenTracing Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
 package io.opentracing.contrib.spring.web.interceptor.itest.common;
 
 import io.opentracing.contrib.spring.web.interceptor.HandlerInterceptorSpanDecorator;