Feature/issue 4698 rxjava2 support (#4743)

* rx2 support

* NO_NOT_USE_RX is for internal use only; plus sanity check if both v1 and v2 are specified

* minor fixes

* one more small fix

modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavaClientCodegen.java

@@ -20,6 +20,8 @@ public class JavaClientCodegen extends AbstractJavaCodegen
     private static final Logger LOGGER = LoggerFactory.getLogger(JavaClientCodegen.class);
 
     public static final String USE_RX_JAVA = "useRxJava";
+    public static final String USE_RX_JAVA2 = "useRxJava2";
+    public static final String DO_NOT_USE_RX = "doNotUseRx";
     public static final String USE_PLAY24_WS = "usePlay24WS";
     public static final String PARCELABLE_MODEL = "parcelableModel";
 
@@ -28,6 +30,8 @@ public class JavaClientCodegen extends AbstractJavaCodegen
 
     protected String gradleWrapperPackage = "gradle.wrapper";
     protected boolean useRxJava = false;
+    protected boolean useRxJava2 = false;
+    protected boolean doNotUseRx = true; // backwards compatibility for swagger configs that specify neither rx1 nor rx2 (mustache does not allow for boolean operators so we need this extra field)
     protected boolean usePlay24WS = false;
     protected boolean parcelableModel = false;
     protected boolean useBeanValidation = false;
@@ -43,6 +47,7 @@ public class JavaClientCodegen extends AbstractJavaCodegen
         modelPackage = "io.swagger.client.model";
 
         cliOptions.add(CliOption.newBoolean(USE_RX_JAVA, "Whether to use the RxJava adapter with the retrofit2 library."));
+        cliOptions.add(CliOption.newBoolean(USE_RX_JAVA2, "Whether to use the RxJava2 adapter with the retrofit2 library."));
         cliOptions.add(CliOption.newBoolean(PARCELABLE_MODEL, "Whether to generate models for Android that implement Parcelable with the okhttp-gson library."));
         cliOptions.add(CliOption.newBoolean(USE_PLAY24_WS, "Use Play! 2.4 Async HTTP client (Play WS API)"));
         cliOptions.add(CliOption.newBoolean(SUPPORT_JAVA6, "Whether to support Java6 with the Jersey1 library."));
@@ -54,7 +59,7 @@ public class JavaClientCodegen extends AbstractJavaCodegen
         supportedLibraries.put("jersey2", "HTTP client: Jersey client 2.22.2. JSON processing: Jackson 2.7.0");
         supportedLibraries.put("okhttp-gson", "HTTP client: OkHttp 2.7.5. JSON processing: Gson 2.6.2. Enable Parcelable modles on Android using '-DparcelableModel=true'");
         supportedLibraries.put(RETROFIT_1, "HTTP client: OkHttp 2.7.5. JSON processing: Gson 2.3.1 (Retrofit 1.9.0). IMPORTANT NOTE: retrofit1.x is no longer actively maintained so please upgrade to 'retrofit2' instead.");
-        supportedLibraries.put(RETROFIT_2, "HTTP client: OkHttp 3.2.0. JSON processing: Gson 2.6.1 (Retrofit 2.0.2). Enable the RxJava adapter using '-DuseRxJava=true'. (RxJava 1.1.3)");
+        supportedLibraries.put(RETROFIT_2, "HTTP client: OkHttp 3.2.0. JSON processing: Gson 2.6.1 (Retrofit 2.0.2). Enable the RxJava adapter using '-DuseRxJava[2]=true'. (RxJava 1.x or 2.x)");
 
         CliOption libraryOption = new CliOption(CodegenConstants.LIBRARY, "library template (sub-template) to use");
         libraryOption.setEnum(supportedLibraries);
@@ -84,9 +89,17 @@ public class JavaClientCodegen extends AbstractJavaCodegen
     public void processOpts() {
         super.processOpts();
 
-        if (additionalProperties.containsKey(USE_RX_JAVA)) {
+        if (additionalProperties.containsKey(USE_RX_JAVA) && additionalProperties.containsKey(USE_RX_JAVA2)) {
+            LOGGER.warn("You specified both RxJava versions 1 and 2 but they are mutually exclusive. Defaulting to v2.");
+        } else if (additionalProperties.containsKey(USE_RX_JAVA)) {
             this.setUseRxJava(Boolean.valueOf(additionalProperties.get(USE_RX_JAVA).toString()));
         }
+        if (additionalProperties.containsKey(USE_RX_JAVA2)) {
+            this.setUseRxJava2(Boolean.valueOf(additionalProperties.get(USE_RX_JAVA2).toString()));
+        }
+	if (!useRxJava && !useRxJava2) {
+	    additionalProperties.put(DO_NOT_USE_RX, true);
+	}
         if (additionalProperties.containsKey(USE_PLAY24_WS)) {
             this.setUsePlay24WS(Boolean.valueOf(additionalProperties.get(USE_PLAY24_WS).toString()));
         }
@@ -335,6 +348,16 @@ public class JavaClientCodegen extends AbstractJavaCodegen
 
     public void setUseRxJava(boolean useRxJava) {
         this.useRxJava = useRxJava;
+        doNotUseRx = false;
+    }
+
+    public void setUseRxJava2(boolean useRxJava2) {
+        this.useRxJava2 = useRxJava2;
+        doNotUseRx = false;
+    }
+
+    public void setDoNotUseRx(boolean doNotUseRx) {
+        this.doNotUseRx = doNotUseRx;
     }
 
     public void setUsePlay24WS(boolean usePlay24WS) {

modules/swagger-codegen/src/main/resources/Java/libraries/retrofit2/ApiClient.mustache

@@ -23,6 +23,7 @@ import java.time.format.DateTimeFormatter;
 import retrofit2.Converter;
 import retrofit2.Retrofit;
 {{#useRxJava}}import retrofit2.adapter.rxjava.RxJavaCallAdapterFactory;{{/useRxJava}}
+{{#useRxJava2}}import com.jakewharton.retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory;{{/useRxJava2}}
 import retrofit2.converter.gson.GsonConverterFactory;
 import retrofit2.converter.scalars.ScalarsConverterFactory;
 
@@ -150,6 +151,7 @@ public class ApiClient {
                 .Builder()
                 .baseUrl(baseUrl)
                 {{#useRxJava}}.addCallAdapterFactory(RxJavaCallAdapterFactory.create()){{/useRxJava}}
+                {{#useRxJava2}}.addCallAdapterFactory(RxJava2CallAdapterFactory.create()){{/useRxJava2}}
                 .addConverterFactory(ScalarsConverterFactory.create())
                 .addConverterFactory(GsonCustomConverterFactory.create(gson));
     }

modules/swagger-codegen/src/main/resources/Java/libraries/retrofit2/api.mustache

@@ -3,7 +3,8 @@ package {{package}};
 import {{invokerPackage}}.CollectionFormats.*;
 
 {{#useRxJava}}import rx.Observable;{{/useRxJava}}
-{{^useRxJava}}import retrofit2.Call;{{/useRxJava}}
+{{#useRxJava2}}import io.reactivex.Observable;{{/useRxJava2}}
+{{#doNotUseRx}}import retrofit2.Call;{{/doNotUseRx}}
 import retrofit2.http.*;
 
 import okhttp3.RequestBody;
@@ -46,7 +47,7 @@ public interface {{classname}} {
   {{/prioritizedContentTypes}}
   {{/formParams}}  
   @{{httpMethod}}("{{path}}")
-  {{^usePlay24WS}}{{#useRxJava}}Observable{{/useRxJava}}{{^useRxJava}}Call{{/useRxJava}}{{/usePlay24WS}}{{#usePlay24WS}}F.Promise<Response{{/usePlay24WS}}<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}>{{#usePlay24WS}}>{{/usePlay24WS}} {{operationId}}({{^allParams}});{{/allParams}}
+  {{^usePlay24WS}}{{^doNotUseRx}}Observable{{/doNotUseRx}}{{#doNotUseRx}}Call{{/doNotUseRx}}{{/usePlay24WS}}{{#usePlay24WS}}F.Promise<Response{{/usePlay24WS}}<{{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}Object{{/returnType}}>{{#usePlay24WS}}>{{/usePlay24WS}} {{operationId}}({{^allParams}});{{/allParams}}
     {{#allParams}}{{>libraries/retrofit2/queryParams}}{{>libraries/retrofit2/pathParams}}{{>libraries/retrofit2/headerParams}}{{>libraries/retrofit2/bodyParams}}{{>libraries/retrofit2/formParams}}{{#hasMore}}, {{/hasMore}}{{^hasMore}}
   );{{/hasMore}}{{/allParams}}
 

modules/swagger-codegen/src/main/resources/Java/libraries/retrofit2/build.gradle.mustache

@@ -101,6 +101,9 @@ ext {
     {{#useRxJava}}
     rx_java_version = "1.1.3"
     {{/useRxJava}}
+    {{#useRxJava2}}
+    rx_java_version = "2.0.5"
+    {{/useRxJava2}}
     {{^java8}}
     jodatime_version = "2.9.3"
     {{/java8}}
@@ -114,6 +117,10 @@ dependencies {
     compile "com.squareup.retrofit2:adapter-rxjava:$retrofit_version"
     compile "io.reactivex:rxjava:$rx_java_version"
     {{/useRxJava}}
+    {{#useRxJava2}}
+    compile "com.jakewharton.retrofit:retrofit2-rxjava2-adapter:1.0.0"
+    compile "io.reactivex.rxjava2:rxjava:$rx_java_version"
+    {{/useRxJava2}}
     compile "io.swagger:swagger-annotations:$swagger_annotations_version"
     compile "org.apache.oltu.oauth2:org.apache.oltu.oauth2.client:$oltu_version"
     {{^java8}}

modules/swagger-codegen/src/main/resources/Java/libraries/retrofit2/build.sbt.mustache

@@ -16,6 +16,10 @@ lazy val root = (project in file(".")).
       "com.squareup.retrofit2" % "adapter-rxjava" % "2.0.2" % "compile",
       "io.reactivex" % "rxjava" % "1.1.3" % "compile",
       {{/useRxJava}}
+      {{#useRxJava2}}
+      "com.jakewharton.retrofit" % "retrofit2-rxjava2-adapter" % "1.0.0" % "compile",
+      "io.reactivex.rxjava2" % "rxjava" % "2.0.5" % "compile",
+      {{/useRxJava2}}
       "io.swagger" % "swagger-annotations" % "1.5.8" % "compile",
       "org.apache.oltu.oauth2" % "org.apache.oltu.oauth2.client" % "1.0.1" % "compile",
       {{^java8}}

modules/swagger-codegen/src/main/resources/Java/libraries/retrofit2/pom.mustache

@@ -213,6 +213,18 @@
       <version>${retrofit-version}</version>
     </dependency>
     {{/useRxJava}}
+    {{#useRxJava2}}
+    <dependency>
+      <groupId>io.reactivex.rxjava2</groupId>
+      <artifactId>rxjava</artifactId>
+      <version>${rxjava-version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.jakewharton.retrofit</groupId>
+      <artifactId>retrofit2-rxjava2-adapter</artifactId>
+      <version>1.0.0</version>
+    </dependency>
+    {{/useRxJava2}}
 
     {{#usePlay24WS}}
     <!-- JSON processing: jackson -->
@@ -269,6 +281,9 @@
     {{#useRxJava}}
     <rxjava-version>1.1.6</rxjava-version>
     {{/useRxJava}}
+    {{#useRxJava2}}
+    <rxjava-version>2.0.5</rxjava-version>
+    {{/useRxJava2}}
     {{^java8}}
     <jodatime-version>2.9.4</jodatime-version>
     {{/java8}}

modules/swagger-codegen/src/test/java/io/swagger/codegen/options/JavaClientOptionsProvider.java

@@ -17,6 +17,7 @@ public class JavaClientOptionsProvider extends JavaOptionsProvider {
         Map<String, String> options = new HashMap<String, String>(super.createOptions());
         options.put(CodegenConstants.LIBRARY, DEFAULT_LIBRARY_VALUE);
         options.put(JavaClientCodegen.USE_RX_JAVA, "false");
+        options.put(JavaClientCodegen.USE_RX_JAVA2, "false");
         options.put(JavaClientCodegen.USE_PLAY24_WS, "false");
         options.put(JavaClientCodegen.PARCELABLE_MODEL, "false");
         options.put(JavaClientCodegen.SUPPORT_JAVA6, "false");