[all] Adds strict spec option

modules/openapi-generator-cli/src/main/java/org/openapitools/codegen/cmd/Generate.java

@@ -214,6 +214,12 @@ public class Generate implements Runnable {
             description = "Skips the default behavior of validating an input specification.")
     private Boolean skipValidateSpec;
 
+    @Option(name = {"--strict-spec"},
+            title = "true/false strict behavior",
+            description = "'MUST' and 'SHALL' wording in OpenAPI spec is strictly adhered to, e.g. no fixes will be applied to documents which pass validation but don't follow the spec.",
+            arity = 1)
+    private Boolean strictSpecBehavior;
+
     @Option(name = {"--log-to-stderr"},
             title = "Log to STDERR",
             description = "write all log messages (not just errors) to STDOUT."
@@ -368,10 +374,15 @@ public void run() {
         if (generateAliasAsModel != null) {
             configurator.setGenerateAliasAsModel(generateAliasAsModel);
         }
+
         if (minimalUpdate != null) {
             configurator.setEnableMinimalUpdate(minimalUpdate);
         }
 
+        if (strictSpecBehavior != null) {
+            configurator.setStrictSpecBehavior(strictSpecBehavior);
+        }
+
         applySystemPropertiesKvpList(systemProperties, configurator);
         applyInstantiationTypesKvpList(instantiationTypes, configurator);
         applyImportMappingsKvpList(importMappings, configurator);

modules/openapi-generator-cli/src/test/java/org/openapitools/codegen/cmd/GenerateTest.java

@@ -277,6 +277,26 @@ public void testSkipOverwrite() throws Exception {
         };
     }
 
+    @Test
+    public void testStrictSpec() throws Exception {
+
+        setupAndRunGenericTest("--strict-spec", "true");
+        new FullVerifications() {
+            {
+                configurator.setStrictSpecBehavior(true);
+                times = 1;
+            }
+        };
+
+        setupAndRunGenericTest("--strict-spec", "false");
+        new FullVerifications() {
+            {
+                configurator.setStrictSpecBehavior(false);
+                times = 1;
+            }
+        };
+    }
+
     @Test
     public void testPackageName() throws Exception {
         final String value = "io.foo.bar.baz";

modules/openapi-generator-maven-plugin/README.md

@@ -57,6 +57,7 @@ mvn clean compile
 - `logToStderr` - write all log messages (not just errors) to STDOUT
 - `enablePostProcessFile` - enable file post-processing hook
 - `skipValidateSpec` - Whether or not to skip validating the input spec prior to generation. By default, invalid specifications will result in an error.
+- `strictSpec` - Whether or not to treat an input document strictly against the spec. 'MUST' and 'SHALL' wording in OpenAPI spec is strictly adhered to, e.g. no fixes will be applied to documents which pass validation but don't follow the spec.
 - `generateAliasAsModel` - generate alias (array, map) as model
 - `generateApis` - generate the apis (`true` by default)
 - `generateApiTests` - generate the api tests (`true` by default. Only available if `generateApis` is `true`)

modules/openapi-generator-maven-plugin/src/main/java/org/openapitools/codegen/plugin/CodeGenMojo.java

@@ -235,6 +235,12 @@ public class CodeGenMojo extends AbstractMojo {
     @Parameter(name = "skipValidateSpec", required = false)
     private Boolean skipValidateSpec;
 
+    /**
+     * To treat a document strictly against the spec.
+     */
+    @Parameter(name = "strictSpec", required = false)
+    private Boolean strictSpecBehavior;
+
     /**
      * To generate alias (array, map) as model
      */
@@ -459,6 +465,10 @@ public void execute() throws MojoExecutionException {
                 configurator.setValidateSpec(!skipValidateSpec);
             }
 
+            if (strictSpecBehavior != null) {
+                configurator.setStrictSpecBehavior(strictSpecBehavior);
+            }
+
             if (logToStderr != null) {
                 configurator.setLogToStderr(logToStderr);
             }

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

@@ -270,4 +270,8 @@ public interface CodegenConfig {
     public boolean isEnableMinimalUpdate();
 
     public void setEnableMinimalUpdate(boolean isEnableMinimalUpdate);
+
+    boolean isStrictSpecBehavior();
+
+    void setStrictSpecBehavior(boolean strictSpecBehavior);
 }

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

@@ -118,6 +118,9 @@ public class DefaultCodegen implements CodegenConfig {
     // flag to indicate whether to only update files whose contents have changed
     protected boolean enableMinimalUpdate = false;
 
+    // acts strictly upon a spec, potentially modifying it to have consistent behavior across generators.
+    protected boolean strictSpecBehavior = true;
+
     // make openapi available to all methods
     protected OpenAPI openAPI;
 
@@ -2387,11 +2390,13 @@ public CodegenOperation fromOperation(String path,
         }
         operationId = removeNonNameElementToCamelCase(operationId);
 
-        if (path.startsWith("/")) {
-            op.path = path;
-        } else {
+        if (isStrictSpecBehavior() && !path.startsWith("/")) {
+            // modifies an operation.path to strictly conform to OpenAPI Spec
             op.path = "/" + path;
+        } else {
+            op.path = path;
         }
+
         op.operationId = toOperationId(operationId);
         op.summary = escapeText(operation.getSummary());
         op.unescapedNotes = operation.getDescription();
@@ -4900,4 +4905,24 @@ public void setEnableMinimalUpdate(boolean enableMinimalUpdate) {
         this.enableMinimalUpdate = enableMinimalUpdate;
     }
 
+    /**
+     * Indicates whether the codegen configuration should treat documents as strictly defined by the OpenAPI specification.
+     *
+     * @return true to act strictly upon spec documents, potentially modifying the spec to strictly fit the spec.
+     */
+    @Override
+    public boolean isStrictSpecBehavior() {
+        return this.strictSpecBehavior;
+    }
+
+    /**
+     * Sets the boolean valid indicating whether generation will work strictly against the specification, potentially making
+     * minor changes to the input document.
+     *
+     * @param strictSpecBehavior true if we will behave strictly, false to allow specification documents which pass validation to be loosely interpreted against the spec.
+     */
+    @Override
+    public void setStrictSpecBehavior(final boolean strictSpecBehavior) {
+        this.strictSpecBehavior = strictSpecBehavior;
+    }
 }

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

@@ -85,6 +85,7 @@ public class CodegenConfigurator implements Serializable {
     private boolean validateSpec;
     private boolean enablePostProcessFile;
     private boolean enableMinimalUpdate;
+    private boolean strictSpecBehavior;
     private String templateDir;
     private String templatingEngineName;
     private String auth;
@@ -117,6 +118,7 @@ public class CodegenConfigurator implements Serializable {
 
     public CodegenConfigurator() {
         this.validateSpec = true;
+        this.strictSpecBehavior = true;
         this.setOutputDir(".");
     }
 
@@ -252,6 +254,15 @@ public CodegenConfigurator setModelNameSuffix(String suffix) {
         return this;
     }
 
+    public boolean isStrictSpecBehavior() {
+        return strictSpecBehavior;
+    }
+
+    public CodegenConfigurator setStrictSpecBehavior(boolean strictSpecBehavior) {
+        this.strictSpecBehavior = strictSpecBehavior;
+        return this;
+    }
+
     public boolean isVerbose() {
         return verbose;
     }

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

@@ -48,7 +48,35 @@ public void testProcessPaths() throws Exception {
         Assert.assertEquals(defaultList.get(3).path, "/path4");
         Assert.assertEquals(defaultList.get(3).allParams.size(), 1);
     }
-
+
+
+    @Test
+    public void testNonStrictProcessPaths() throws Exception {
+        OpenAPI openAPI = TestUtils.createOpenAPI();
+        openAPI.setPaths(new Paths());
+        openAPI.getPaths().addPathItem("path1/", new PathItem().get(new Operation().operationId("op1").responses(new ApiResponses().addApiResponse("201", new ApiResponse().description("OK")))));
+        openAPI.getPaths().addPathItem("path2/", new PathItem().get(new Operation().operationId("op2").addParametersItem(new QueryParameter().name("p1").schema(new StringSchema())).responses(new ApiResponses().addApiResponse("201", new ApiResponse().description("OK")))));
+
+        ClientOptInput opts = new ClientOptInput();
+        opts.setOpenAPI(openAPI);
+        CodegenConfig config = new DefaultCodegen();
+        config.setStrictSpecBehavior(false);
+        opts.setConfig(config);
+        opts.setOpts(new ClientOpts());
+
+        DefaultGenerator generator = new DefaultGenerator();
+        generator.opts(opts);
+        Map<String, List<CodegenOperation>> result = generator.processPaths(openAPI.getPaths());
+        Assert.assertEquals(result.size(), 1);
+        List<CodegenOperation> defaultList = result.get("Default");
+        Assert.assertEquals(defaultList.size(), 2);
+        Assert.assertEquals(defaultList.get(0).path, "path1/");
+        Assert.assertEquals(defaultList.get(0).allParams.size(), 0);
+        Assert.assertEquals(defaultList.get(1).path, "path2/");
+        Assert.assertEquals(defaultList.get(1).allParams.size(), 1);
+    }
+
+
     @Test
     public void minimalUpdateTest() throws IOException {
         OpenAPI openAPI = TestUtils.createOpenAPI();