[GO] Go Server: preserve order of the routes as defined in the OpenAPI file (#19550)

* Add skipSortingOperations configuration option

* Skip sorting operations for go-server

* Add test verifyOrder

* Regenerate samples

Author: gcatanese

modules/openapi-generator/src/main/java/org/openapitools/codegen/CodegenConfig.java

@@ -256,6 +256,10 @@ public interface CodegenConfig {
 
     void setSkipOperationExample(boolean skipOperationExample);
 
+    boolean isSkipSortingOperations();
+
+    void setSkipSortingOperations(boolean skipSortingOperations);
+
     public boolean isHideGenerationTimestamp();
 
     public void setHideGenerationTimestamp(boolean hideGenerationTimestamp);

modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java

@@ -224,6 +224,8 @@ apiTemplateFiles are for API outputs only (controllers/handlers).
     @Getter @Setter
     protected int removeOperationIdPrefixCount = 1;
     protected boolean skipOperationExample;
+    // sort operations by default
+    protected boolean skipSortingOperations = false;
 
     protected final static Pattern XML_MIME_PATTERN = Pattern.compile("(?i)application\\/(.*)[+]?xml(;.*)?");
     protected final static Pattern JSON_MIME_PATTERN = Pattern.compile("(?i)application\\/json(;.*)?");
@@ -6154,6 +6156,16 @@ public void setSkipOperationExample(boolean skipOperationExample) {
         this.skipOperationExample = skipOperationExample;
     }
 
+    @Override
+    public boolean isSkipSortingOperations() {
+        return this.skipSortingOperations;
+    }
+
+    @Override
+    public void setSkipSortingOperations(boolean skipSortingOperations) {
+        this.skipSortingOperations = skipSortingOperations;
+    }
+
     @Override
     public boolean isHideGenerationTimestamp() {
         return hideGenerationTimestamp;

modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultGenerator.java

@@ -121,6 +121,7 @@ public Generator opts(ClientOptInput opts) {
         this.opts = opts;
         this.openAPI = opts.getOpenAPI();
         this.config = opts.getConfig();
+
         List<TemplateDefinition> userFiles = opts.getUserDefinedTemplates();
         if (userFiles != null) {
             this.userDefinedTemplates = Collections.unmodifiableList(userFiles);
@@ -680,7 +681,10 @@ void generateApis(List<File> files, List<OperationsMap> allOperations, List<Mode
         for (String tag : paths.keySet()) {
             try {
                 List<CodegenOperation> ops = paths.get(tag);
-                ops.sort((one, another) -> ObjectUtils.compare(one.operationId, another.operationId));
+                if(!this.config.isSkipSortingOperations()) {
+                    // sort operations by operationId
+                    ops.sort((one, another) -> ObjectUtils.compare(one.operationId, another.operationId));
+                }
                 OperationsMap operation = processOperations(config, tag, ops, allModels);
                 URL url = URLPathUtils.getServerURL(openAPI, config.serverVariableOverrides());
                 operation.put("basePath", basePath);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoServerCodegen.java

@@ -66,6 +66,9 @@ public class GoServerCodegen extends AbstractGoCodegen {
     public GoServerCodegen() {
         super();
 
+        // skip sorting of operations to preserve the order found in the OpenAPI spec file
+        super.setSkipSortingOperations(true);
+
         modifyFeatureSet(features -> features
                 .includeDocumentationFeatures(DocumentationFeature.Readme)
                 .wireFormatFeatures(EnumSet.of(WireFormatFeature.JSON, WireFormatFeature.XML))

modules/openapi-generator/src/test/java/org/openapitools/codegen/goserver/GoServerCodegenTest.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2018 OpenAPI-Generator Contributors (https://openapi-generator.tech)
+ * Copyright 2018 SmartBear Software
+ *
+ * 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
+ *
+ *     https://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 org.openapitools.codegen.goserver;
+
+import org.openapitools.codegen.DefaultGenerator;
+import org.openapitools.codegen.TestUtils;
+import org.openapitools.codegen.config.CodegenConfigurator;
+import org.testng.Assert;
+import org.testng.annotations.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.List;
+
+public class GoServerCodegenTest {
+
+    @Test
+    public void verifyGoMod() throws IOException {
+        File output = Files.createTempDirectory("test").toFile();
+        output.deleteOnExit();
+
+        final CodegenConfigurator configurator = createDefaultCodegenConfigurator(output)
+                .setInputSpec("src/test/resources/3_0/go-server/route-order.yaml");
+
+        DefaultGenerator generator = new DefaultGenerator();
+        List<File> files = generator.opts(configurator.toClientOptInput()).generate();
+        files.forEach(File::deleteOnExit);
+
+        TestUtils.assertFileExists(Paths.get(output + "/go.mod"));
+        TestUtils.assertFileContains(Paths.get(output + "/go.mod"),
+                "module github.com/my-user/my-repo");
+        TestUtils.assertFileContains(Paths.get(output + "/go.mod"),
+                "require github.com/gorilla/mux v1.8.0");
+    }
+
+    @Test
+    public void verifyOrder() throws IOException {
+        File output = Files.createTempDirectory("test").toFile();
+        output.deleteOnExit();
+
+        final CodegenConfigurator configurator = createDefaultCodegenConfigurator(output)
+                .setInputSpec("src/test/resources/3_0/go-server/route-order.yaml");
+
+        DefaultGenerator generator = new DefaultGenerator();
+        List<File> files = generator.opts(configurator.toClientOptInput()).generate();
+        files.forEach(File::deleteOnExit);
+
+        TestUtils.assertFileExists(Paths.get(output + "/go/routers.go"));
+        TestUtils.assertFileContains(Paths.get(output + "/go/routers.go"),
+                "type Routes map[string]Route");
+
+        TestUtils.assertFileExists(Paths.get(output + "/go/api_dev.go"));
+        // verify /getPath/latest is first route
+        Assert.assertEquals(Files.readAllLines(Paths.get(output + "/go/api_dev.go")).get(52), "\t\t\"GetLatest\": Route{");
+        // verify /getPath/{id} is second route
+        Assert.assertEquals(Files.readAllLines(Paths.get(output + "/go/api_dev.go")).get(57), "\t\t\"GetById\": Route{");
+
+    }
+
+    private static CodegenConfigurator createDefaultCodegenConfigurator(File output) {
+        return new CodegenConfigurator()
+                .setGeneratorName("go-server")
+                .setGitUserId("my-user")
+                .setGitRepoId("my-repo")
+                .setPackageName("mypackage")
+                .setOutputDir(output.getAbsolutePath().replace("\\", "/"));
+    }
+
+}

modules/openapi-generator/src/test/resources/3_0/go-server/route-order.yaml

@@ -0,0 +1,33 @@
+openapi: 3.0.0
+
+info:
+  version: 1.0.0
+  title: Simple no path and body param spec
+
+paths:
+  /getPath/latest:
+    get:
+      tags:
+        - dev
+      summary: summary
+      description: description
+      operationId: getLatest
+      responses:
+        '204':
+          description: successful operation
+  /getPath/{id}:
+    get:
+      tags:
+        - dev
+      summary: summary
+      description: description
+      operationId: GetById
+      parameters:
+        - name: id
+          in: path
+          required: true
+          schema:
+            type: string
+      responses:
+        '204':
+          description: successful operation