Refactor config mechanism for OkHttp adapter and polish related code

- One config per interceptor instead of the global config
- Polish document and demo

Signed-off-by: Eric Zhao <sczyh16@gmail.com>

sentinel-adapter/sentinel-okhttp-adapter/README.md

@@ -18,22 +18,24 @@ We can add the `SentinelOkHttpInterceptor` interceptor when `OkHttpClient` at in
 
 ```java
 OkHttpClient client = new OkHttpClient.Builder()
-        .addInterceptor(new SentinelOkHttpInterceptor())
+        .addInterceptor(new SentinelOkHttpInterceptor(new SentinelOkHttpConfig()))
         .build();
 ```
 
 ## Configuration
 
-- `SentinelOkHttpConfig` configuration:
+`SentinelOkHttpConfig` configuration:
 
 | name | description | type | default value |
 |------|------------|------|-------|
-| extractor | custom resource extractor | `OkHttpResourceExtractor` | `DefaultOkHttpResourceExtractor` |
+| resourcePrefix | customized resource name prefix | `String` | `okhttp:` |
+| resourceExtractor | customized resource extractor | `OkHttpResourceExtractor` | `DefaultOkHttpResourceExtractor` |
 | fallback | handle request when it is blocked | `OkHttpFallback` | `DefaultOkHttpFallback` |
 
-### extractor (resource extractor)
+### Resource Extractor
 
-We can define `OkHttpResourceExtractor` to custom resource extractor replace `DefaultOkHttpResourceExtractor`, for example: okhttp:GET:ip:port/okhttp/back/1 ==> /okhttp/back/{id}
+We can define `OkHttpResourceExtractor` to customize the logic of extracting resource name from the HTTP request.
+For example: `okhttp:GET:ip:port/okhttp/back/1 ==> /okhttp/back/{id}`
 
 ```java
 OkHttpResourceExtractor extractor = (request, connection) -> {
@@ -44,20 +46,20 @@ OkHttpResourceExtractor extractor = (request, connection) -> {
     }
     return resource;
 };
-SentinelOkHttpConfig.setExtractor(extractor);
 ```
 
-### fallback (Block handling)
+The pattern of default resource name extractor is `${HTTP_METHOD}:${URL}` (e.g. `GET:/foo`).
 
-We can define `OkHttpFallback` to handle request is blocked according to the actual scenario, for example:
+### Fallback (Block handling)
+
+We can define `OkHttpFallback` to handle blocked request. For example:
 
 ```java
 public class DefaultOkHttpFallback implements OkHttpFallback {
 
     @Override
     public Response handle(Request request, Connection connection, BlockException e) {
-        // Just wrap and throw the exception.
+        return new Response(myErrorBuilder);
-        throw new SentinelRpcException(e);
     }
 }
 ```

sentinel-adapter/sentinel-okhttp-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/okhttp/SentinelOkHttpConfig.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 1999-2020 Alibaba Group Holding Ltd.
+ *
+ * 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 com.alibaba.csp.sentinel.adapter.okhttp;
+
+import com.alibaba.csp.sentinel.adapter.okhttp.extractor.DefaultOkHttpResourceExtractor;
+import com.alibaba.csp.sentinel.adapter.okhttp.extractor.OkHttpResourceExtractor;
+import com.alibaba.csp.sentinel.adapter.okhttp.fallback.DefaultOkHttpFallback;
+import com.alibaba.csp.sentinel.adapter.okhttp.fallback.OkHttpFallback;
+import com.alibaba.csp.sentinel.util.AssertUtil;
+
+/**
+ * @author zhaoyuguang
+ * @author Eric Zhao
+ */
+public class SentinelOkHttpConfig {
+
+    public static final String DEFAULT_RESOURCE_PREFIX = "okhttp:";
+
+    private final String resourcePrefix;
+    private final OkHttpResourceExtractor resourceExtractor;
+    private final OkHttpFallback fallback;
+
+    public SentinelOkHttpConfig() {
+        this(DEFAULT_RESOURCE_PREFIX);
+    }
+
+    public SentinelOkHttpConfig(String resourcePrefix) {
+        this(resourcePrefix, new DefaultOkHttpResourceExtractor(), new DefaultOkHttpFallback());
+    }
+
+    public SentinelOkHttpConfig(OkHttpResourceExtractor resourceExtractor, OkHttpFallback fallback) {
+        this(DEFAULT_RESOURCE_PREFIX, resourceExtractor, fallback);
+    }
+
+    public SentinelOkHttpConfig(String resourcePrefix,
+                                OkHttpResourceExtractor resourceExtractor,
+                                OkHttpFallback fallback) {
+        AssertUtil.notNull(resourceExtractor, "resourceExtractor cannot be null");
+        AssertUtil.notNull(fallback, "fallback cannot be null");
+        this.resourcePrefix = resourcePrefix;
+        this.resourceExtractor = resourceExtractor;
+        this.fallback = fallback;
+    }
+
+    public String getResourcePrefix() {
+        return resourcePrefix;
+    }
+
+    public OkHttpResourceExtractor getResourceExtractor() {
+        return resourceExtractor;
+    }
+
+    public OkHttpFallback getFallback() {
+        return fallback;
+    }
+
+    @Override
+    public String toString() {
+        return "SentinelOkHttpConfig{" +
+            "resourcePrefix='" + resourcePrefix + '\'' +
+            ", resourceExtractor=" + resourceExtractor +
+            ", fallback=" + fallback +
+            '}';
+    }
+}

sentinel-adapter/sentinel-okhttp-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/okhttp/SentinelOkHttpInterceptor.java

@@ -16,9 +16,10 @@
 package com.alibaba.csp.sentinel.adapter.okhttp;
 
 import com.alibaba.csp.sentinel.*;
-import com.alibaba.csp.sentinel.adapter.okhttp.config.SentinelOkHttpConfig;
 import com.alibaba.csp.sentinel.slots.block.BlockException;
+import com.alibaba.csp.sentinel.util.AssertUtil;
 import com.alibaba.csp.sentinel.util.StringUtil;
+
 import okhttp3.Interceptor;
 import okhttp3.Request;
 import okhttp3.Response;
@@ -30,22 +31,33 @@ import java.io.IOException;
  */
 public class SentinelOkHttpInterceptor implements Interceptor {
 
+    private final SentinelOkHttpConfig config;
+
+    public SentinelOkHttpInterceptor() {
+        this.config = new SentinelOkHttpConfig();
+    }
+
+    public SentinelOkHttpInterceptor(SentinelOkHttpConfig config) {
+        AssertUtil.notNull(config, "config cannot be null");
+        this.config = config;
+    }
+
     @Override
     public Response intercept(Chain chain) throws IOException {
         Entry entry = null;
         try {
             Request request = chain.request();
-            String name = SentinelOkHttpConfig.getExtractor().extract(request.url().toString(), request, chain.connection());
+            String name = config.getResourceExtractor().extract(request, chain.connection());
-            if (!StringUtil.isEmpty(SentinelOkHttpConfig.getPrefix())) {
+            if (StringUtil.isNotBlank(config.getResourcePrefix())) {
-                name = SentinelOkHttpConfig.getPrefix() + name;
+                name = config.getResourcePrefix() + name;
             }
             entry = SphU.entry(name, ResourceTypeConstants.COMMON_WEB, EntryType.OUT);
             return chain.proceed(request);
         } catch (BlockException e) {
-            return SentinelOkHttpConfig.getFallback().handle(chain.request(), chain.connection(), e);
+            return config.getFallback().handle(chain.request(), chain.connection(), e);
-        } catch (Throwable t) {
+        } catch (IOException ex) {
-            Tracer.traceEntry(t, entry);
+            Tracer.traceEntry(ex, entry);
-            throw t;
+            throw ex;
         } finally {
             if (entry != null) {
                 entry.exit();

sentinel-adapter/sentinel-okhttp-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/okhttp/config/SentinelOkHttpConfig.java

@@ -1,59 +0,0 @@
-/*
- * Copyright 1999-2020 Alibaba Group Holding Ltd.
- *
- * 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 com.alibaba.csp.sentinel.adapter.okhttp.config;
-
-import com.alibaba.csp.sentinel.adapter.okhttp.extractor.DefaultOkHttpResourceExtractor;
-import com.alibaba.csp.sentinel.adapter.okhttp.extractor.OkHttpResourceExtractor;
-import com.alibaba.csp.sentinel.adapter.okhttp.fallback.DefaultOkHttpFallback;
-import com.alibaba.csp.sentinel.adapter.okhttp.fallback.OkHttpFallback;
-import com.alibaba.csp.sentinel.util.AssertUtil;
-
-/**
- * @author zhaoyuguang
- */
-public final class SentinelOkHttpConfig {
-
-    private static volatile String prefix = "okhttp:";
-    private static volatile OkHttpResourceExtractor extractor = new DefaultOkHttpResourceExtractor();
-    private static volatile OkHttpFallback fallback = new DefaultOkHttpFallback();
-
-    public static String getPrefix() {
-        return prefix;
-    }
-
-    public static void setPrefix(String prefix) {
-        AssertUtil.notNull(prefix, "prefix cannot be null");
-        SentinelOkHttpConfig.prefix = prefix;
-    }
-
-    public static OkHttpResourceExtractor getExtractor() {
-        return extractor;
-    }
-
-    public static void setExtractor(OkHttpResourceExtractor extractor) {
-        AssertUtil.notNull(extractor, "extractor cannot be null");
-        SentinelOkHttpConfig.extractor = extractor;
-    }
-
-    public static OkHttpFallback getFallback() {
-        return fallback;
-    }
-
-    public static void setFallback(OkHttpFallback fallback) {
-        AssertUtil.notNull(fallback, "fallback cannot be null");
-        SentinelOkHttpConfig.fallback = fallback;
-    }
-}

sentinel-adapter/sentinel-okhttp-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/okhttp/extractor/DefaultOkHttpResourceExtractor.java

@@ -24,7 +24,7 @@ import okhttp3.Request;
 public class DefaultOkHttpResourceExtractor implements OkHttpResourceExtractor {
 
     @Override
-    public String extract(String url, Request request, Connection connection) {
+    public String extract(Request request, Connection connection) {
         return request.method() + ":" + request.url().toString();
     }
 }

sentinel-adapter/sentinel-okhttp-adapter/src/main/java/com/alibaba/csp/sentinel/adapter/okhttp/extractor/OkHttpResourceExtractor.java

@@ -23,5 +23,12 @@ import okhttp3.Request;
  */
 public interface OkHttpResourceExtractor {
 
-    String extract(String url, Request request, Connection connection);
+    /**
+     * Extracts the resource name from the HTTP request.
+     *
+     * @param request    HTTP request entity
+     * @param connection HTTP connection
+     * @return the resource name of current request
+     */
+    String extract(Request request, Connection connection);
 }

sentinel-adapter/sentinel-okhttp-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/okhttp/SentinelOkHttpInterceptorTest.java

@@ -17,8 +17,8 @@ package com.alibaba.csp.sentinel.adapter.okhttp;
 
 import com.alibaba.csp.sentinel.Constants;
 import com.alibaba.csp.sentinel.adapter.okhttp.app.TestApplication;
-import com.alibaba.csp.sentinel.adapter.okhttp.config.SentinelOkHttpConfig;
 import com.alibaba.csp.sentinel.adapter.okhttp.extractor.OkHttpResourceExtractor;
+import com.alibaba.csp.sentinel.adapter.okhttp.fallback.DefaultOkHttpFallback;
 import com.alibaba.csp.sentinel.node.ClusterNode;
 import com.alibaba.csp.sentinel.slots.clusterbuilder.ClusterBuilderSlot;
 import okhttp3.Connection;
@@ -48,17 +48,17 @@ public class SentinelOkHttpInterceptorTest {
 
     @Test
     public void testSentinelOkHttpInterceptor0() throws Exception {
-
+        // With prefix
+        SentinelOkHttpConfig config = new SentinelOkHttpConfig("okhttp:");
         String url0 = "http://localhost:" + port + "/okhttp/back";
-        SentinelOkHttpConfig.setPrefix("okhttp:");
         OkHttpClient client = new OkHttpClient.Builder()
-                .addInterceptor(new SentinelOkHttpInterceptor())
+                .addInterceptor(new SentinelOkHttpInterceptor(config))
                 .build();
         Request request = new Request.Builder()
                 .url(url0)
                 .build();
         System.out.println(client.newCall(request).execute().body().string());
-        ClusterNode cn = ClusterBuilderSlot.getClusterNode(SentinelOkHttpConfig.getPrefix() + "GET:" + url0);
+        ClusterNode cn = ClusterBuilderSlot.getClusterNode(config.getResourcePrefix() + "GET:" + url0);
         assertNotNull(cn);
 
         Constants.ROOT.removeChildList();
@@ -69,25 +69,26 @@ public class SentinelOkHttpInterceptorTest {
     public void testSentinelOkHttpInterceptor1() throws Exception {
 
         String url0 = "http://localhost:" + port + "/okhttp/back/1";
-        SentinelOkHttpConfig.setExtractor(new OkHttpResourceExtractor() {
+        SentinelOkHttpConfig config = new SentinelOkHttpConfig(new OkHttpResourceExtractor() {
             @Override
-            public String extract(String url, Request request, Connection connection) {
+            public String extract(Request request, Connection connection) {
                 String regex = "/okhttp/back/";
+                String url = request.url().toString();
                 if (url.contains(regex)) {
                     url = url.substring(0, url.indexOf(regex) + regex.length()) + "{id}";
                 }
                 return request.method() + ":" + url;
             }
-        });
+        }, new DefaultOkHttpFallback());
         OkHttpClient client = new OkHttpClient.Builder()
-                .addInterceptor(new SentinelOkHttpInterceptor())
+                .addInterceptor(new SentinelOkHttpInterceptor(config))
                 .build();
         Request request = new Request.Builder()
                 .url(url0)
                 .build();
         System.out.println(client.newCall(request).execute().body().string());
 
-        String url1 = SentinelOkHttpConfig.getPrefix() + "GET:http://localhost:" + port + "/okhttp/back/{id}";
+        String url1 = config.getResourcePrefix() + "GET:http://localhost:" + port + "/okhttp/back/{id}";
         ClusterNode cn = ClusterBuilderSlot.getClusterNode(url1);
         assertNotNull(cn);
 

sentinel-adapter/sentinel-okhttp-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/okhttp/config/SentinelOkHttpConfigTest.java

@@ -15,6 +15,10 @@
  */
 package com.alibaba.csp.sentinel.adapter.okhttp.config;
 
+import com.alibaba.csp.sentinel.adapter.okhttp.SentinelOkHttpConfig;
+import com.alibaba.csp.sentinel.adapter.okhttp.extractor.DefaultOkHttpResourceExtractor;
+import com.alibaba.csp.sentinel.adapter.okhttp.fallback.DefaultOkHttpFallback;
+
 import org.junit.Test;
 
 /**
@@ -22,18 +26,13 @@ import org.junit.Test;
  */
 public class SentinelOkHttpConfigTest {
 
-    @Test(expected = IllegalArgumentException.class)
-    public void testConfigSetPrefix() {
-        SentinelOkHttpConfig.setPrefix(null);
-    }
-
     @Test(expected = IllegalArgumentException.class)
     public void testConfigSetCleaner() {
-        SentinelOkHttpConfig.setExtractor(null);
+        SentinelOkHttpConfig config = new SentinelOkHttpConfig(null, new DefaultOkHttpFallback());
     }
 
     @Test(expected = IllegalArgumentException.class)
     public void testConfigSetFallback() {
-        SentinelOkHttpConfig.setFallback(null);
+        SentinelOkHttpConfig config = new SentinelOkHttpConfig(new DefaultOkHttpResourceExtractor(), null);
     }
 }

sentinel-adapter/sentinel-okhttp-adapter/src/test/java/com/alibaba/csp/sentinel/adapter/okhttp/extractor/OkHttpResourceExtractorTest.java

@@ -15,7 +15,6 @@
  */
 package com.alibaba.csp.sentinel.adapter.okhttp.extractor;
 
-import com.alibaba.csp.sentinel.adapter.okhttp.config.SentinelOkHttpConfig;
 import okhttp3.Connection;
 import okhttp3.Request;
 import org.junit.Test;
@@ -32,19 +31,19 @@ public class OkHttpResourceExtractorTest {
         OkHttpResourceExtractor extractor = new DefaultOkHttpResourceExtractor();
         String url = "http://localhost:8083/okhttp/back";
         Request request = new Request.Builder()
-                .url(url)
+            .url(url)
-                .build();
+            .build();
-        extractor.extract(url, request, null);
+        String resource = extractor.extract(request, null);
-        System.out.println(extractor.extract(url, request, null));
+        assertEquals("GET:" + url, resource);
-        assertEquals("GET:"+url, extractor.extract(url, request, null));
     }
 
     @Test
     public void testCustomizeOkHttpUrlCleaner() {
         OkHttpResourceExtractor extractor = new OkHttpResourceExtractor() {
             @Override
-            public String extract(String url, Request request, Connection connection) {
+            public String extract(Request request, Connection connection) {
                 String regex = "/okhttp/back/";
+                String url = request.url().toString();
                 if (url.contains(regex)) {
                     url = url.substring(0, url.indexOf(regex) + regex.length()) + "{id}";
                 }
@@ -53,9 +52,8 @@ public class OkHttpResourceExtractorTest {
         };
         String url = "http://localhost:8083/okhttp/back/abc";
         Request request = new Request.Builder()
-                .url(url)
+            .url(url)
-                .build();
+            .build();
-        extractor.extract(url, request, null);
+        assertEquals("GET:http://localhost:8083/okhttp/back/{id}", extractor.extract(request, null));
-        assertEquals("GET:http://localhost:8083/okhttp/back/{id}", extractor.extract(url, request, null));
     }
 }

sentinel-demo/sentinel-demo-okhttp/pom.xml

@@ -17,10 +17,6 @@
     </properties>
 
     <dependencies>
-        <dependency>
-            <groupId>com.alibaba.csp</groupId>
-            <artifactId>sentinel-transport-simple-http</artifactId>
-        </dependency>
         <dependency>
             <groupId>com.alibaba.csp</groupId>
             <artifactId>sentinel-okhttp-adapter</artifactId>
@@ -41,5 +37,11 @@
             <artifactId>okhttp</artifactId>
             <version>${okhttp.version}</version>
         </dependency>
+
+        <!-- Add this so that we could display the resources via /tree command -->
+        <dependency>
+            <groupId>com.alibaba.csp</groupId>
+            <artifactId>sentinel-transport-simple-http</artifactId>
+        </dependency>
     </dependencies>
 </project>

sentinel-demo/sentinel-demo-okhttp/src/main/java/com/alibaba/csp/sentinel/demo/okhttp/OkHttpDemoApplication.java

@@ -15,11 +15,6 @@
  */
 package com.alibaba.csp.sentinel.demo.okhttp;
 
-import com.alibaba.csp.sentinel.adapter.okhttp.config.SentinelOkHttpConfig;
-import com.alibaba.csp.sentinel.adapter.okhttp.extractor.OkHttpResourceExtractor;
-import okhttp3.Connection;
-import okhttp3.Request;
-import org.springframework.boot.CommandLineRunner;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 
@@ -27,23 +22,9 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  * @author zhaoyuguang
  */
 @SpringBootApplication
-public class OkHttpDemoApplication implements CommandLineRunner {
+public class OkHttpDemoApplication {
 
     public static void main(String[] args) {
         SpringApplication.run(OkHttpDemoApplication.class);
     }
-
-    @Override
-    public void run(String... args) {
-        SentinelOkHttpConfig.setExtractor(new OkHttpResourceExtractor() {
-            @Override
-            public String extract(String url, Request request, Connection connection) {
-                String regex = "/okhttp/back/";
-                if (url.contains(regex)) {
-                    url = url.substring(0, url.indexOf(regex) + regex.length()) + "{id}";
-                }
-                return request.method() + ":" + url;
-            }
-        });
-    }
 }

sentinel-demo/sentinel-demo-okhttp/src/main/java/com/alibaba/csp/sentinel/demo/okhttp/controller/OkHttpTestController.java

@@ -15,7 +15,10 @@
  */
 package com.alibaba.csp.sentinel.demo.okhttp.controller;
 
+import com.alibaba.csp.sentinel.adapter.okhttp.SentinelOkHttpConfig;
 import com.alibaba.csp.sentinel.adapter.okhttp.SentinelOkHttpInterceptor;
+import com.alibaba.csp.sentinel.adapter.okhttp.fallback.DefaultOkHttpFallback;
+
 import okhttp3.OkHttpClient;
 import okhttp3.Request;
 import okhttp3.Response;
@@ -35,6 +38,17 @@ public class OkHttpTestController {
     @Value("${server.port}")
     private Integer port;
 
+    private final OkHttpClient client = new OkHttpClient.Builder()
+        .addInterceptor(new SentinelOkHttpInterceptor(new SentinelOkHttpConfig((request, connection) -> {
+            String regex = "/okhttp/back/";
+            String url = request.url().toString();
+            if (url.contains(regex)) {
+                url = url.substring(0, url.indexOf(regex) + regex.length()) + "{id}";
+            }
+            return request.method() + ":" + url;
+        }, new DefaultOkHttpFallback())))
+        .build();
+
     @RequestMapping("/okhttp/back")
     public String back() {
         return "Welcome Back!";
@@ -56,12 +70,9 @@ public class OkHttpTestController {
     }
 
     private String getRemoteString(String id) throws IOException {
-        OkHttpClient client = new OkHttpClient.Builder()
-                .addInterceptor(new SentinelOkHttpInterceptor())
-                .build();
         Request request = new Request.Builder()
-                .url("http://localhost:" + port + "/okhttp/back" + (id == null ? "" : "/" + id))
+            .url("http://localhost:" + port + "/okhttp/back" + (id == null ? "" : "/" + id))
-                .build();
+            .build();
         Response response = client.newCall(request).execute();
         return response.body().string();
     }