feat(go): add enumUnknownDefaultCase config option

Author: marceljk

bin/configs/go-petstore.yaml

@@ -16,6 +16,7 @@ additionalProperties:
   disallowAdditionalPropertiesIfNotPresent: false
   generateInterfaces: true
   useDefaultValuesForRequiredVars: "true"
+  enumUnknownDefaultCase: true
 enumNameMappings:
   delivered: SHIPPED
 

docs/generators/go.md

@@ -20,6 +20,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 | ------ | ----------- | ------ | ------- |
 |disallowAdditionalPropertiesIfNotPresent|If false, the 'additionalProperties' implementation (set to true by default) is compliant with the OAS and JSON schema specifications. If true (default), keep the old (incorrect) behaviour that 'additionalProperties' is set to false by default.|<dl><dt>**false**</dt><dd>The 'additionalProperties' implementation is compliant with the OAS and JSON schema specifications.</dd><dt>**true**</dt><dd>Keep the old (incorrect) behaviour that 'additionalProperties' is set to false by default.</dd></dl>|true|
 |enumClassPrefix|Prefix enum with class name| |false|
+|enumUnknownDefaultCase|If the server adds new enum cases, that are unknown by an old spec/client, the client will fail to parse the network response.With this option enabled, each enum will have a new case, 'unknown_default_open_api', so that when the server sends an enum case that is not known by the client/spec, they can safely fallback to this case.|<dl><dt>**false**</dt><dd>No changes to the enum's are made, this is the default option.</dd><dt>**true**</dt><dd>With this option enabled, each enum will have a new case, 'unknown_default_open_api', so that when the enum case sent by the server is not known by the client/spec, can safely be decoded to this case.</dd></dl>|false|
 |generateInterfaces|Generate interfaces for api classes| |false|
 |generateMarshalJSON|Generate MarshalJSON method| |true|
 |generateUnmarshalJSON|Generate UnmarshalJSON method| |true|

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

@@ -892,6 +892,18 @@ public String escapeQuotationMark(String input) {
         return input.replace("\"", "");
     }
 
+    /**
+     * checks if the data should be classified as "string" in enum
+     * In the future, we may rename this function to "isEnumString"
+     *
+     * @param dataType data type
+     * @return true if it's a enum string
+     */
+    @Override
+    public boolean isDataTypeString(String dataType) {
+        return "string".equalsIgnoreCase(dataType);
+    }
+
     @Override
     public String escapeUnsafeCharacters(String input) {
         return input.replace("*/", "*_/").replace("/*", "/_*");
@@ -908,6 +920,8 @@ public Map<String, String> createMapping(String key, String value) {
     public String toEnumValue(String value, String datatype) {
         if (isNumberType(datatype) || "bool".equals(datatype)) {
             return value;
+        } else if (isDataTypeString(datatype) && value.indexOf("\"") == 0 && value.lastIndexOf("\"") == value.length() - 1) {
+            return value;
         } else {
             return "\"" + escapeText(value) + "\"";
         }

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

@@ -153,6 +153,19 @@ public GoClientCodegen() {
         cliOptions.add(CliOption.newBoolean(WITH_GO_MOD, "Generate go.mod and go.sum", true));
         cliOptions.add(CliOption.newBoolean(CodegenConstants.GENERATE_MARSHAL_JSON, CodegenConstants.GENERATE_MARSHAL_JSON_DESC, true));
         cliOptions.add(CliOption.newBoolean(CodegenConstants.GENERATE_UNMARSHAL_JSON, CodegenConstants.GENERATE_UNMARSHAL_JSON_DESC, true));
+
+        CliOption enumUnknownDefaultCaseOpt = CliOption.newBoolean(
+                CodegenConstants.ENUM_UNKNOWN_DEFAULT_CASE,
+                CodegenConstants.ENUM_UNKNOWN_DEFAULT_CASE_DESC).defaultValue(Boolean.FALSE.toString());
+        Map<String, String> enumUnknownDefaultCaseOpts = new HashMap<>();
+        enumUnknownDefaultCaseOpts.put("false",
+                "No changes to the enum's are made, this is the default option.");
+        enumUnknownDefaultCaseOpts.put("true",
+                "With this option enabled, each enum will have a new case, 'unknown_default_open_api', so that when the enum case sent by the server is not known by the client/spec, can safely be decoded to this case.");
+        enumUnknownDefaultCaseOpt.setEnum(enumUnknownDefaultCaseOpts);
+        cliOptions.add(enumUnknownDefaultCaseOpt);
+        this.setEnumUnknownDefaultCase(false);
+
         this.setWithGoMod(true);
     }
 
@@ -411,6 +424,7 @@ public void updateCodegenPropertyEnum(CodegenProperty var) {
         }
     }
 
+
     /**
      * Determines if at least one of the allOf pieces of a schema are of type string
      *

modules/openapi-generator/src/main/resources/go/model_enum.mustache

@@ -35,7 +35,19 @@ func (v *{{{classname}}}) UnmarshalJSON(src []byte) error {
 		}
 	}
 
+	{{#enumUnknownDefaultCase}}
+	{{#allowableValues}}
+	{{#enumVars}}
+	{{#-last}}
+	*v = {{#enumClassPrefix}}{{{classname.toUpperCase}}}_{{/enumClassPrefix}}{{{name}}}
+	return nil
+	{{/-last}}
+	{{/enumVars}}
+	{{/allowableValues}}
+	{{/enumUnknownDefaultCase}}
+	{{^enumUnknownDefaultCase}}
 	return fmt.Errorf("%+v is not a valid {{classname}}", value)
+	{{/enumUnknownDefaultCase}}
 }
 
 // New{{{classname}}}FromValue returns a pointer to a valid {{{classname}}}

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

@@ -55,5 +55,6 @@ protected void verifyOptions() {
         verify(clientCodegen).setGenerateMarshalJSON(GoClientOptionsProvider.GENERATE_MARSHAL_JSON_VALUE);
         verify(clientCodegen).setGenerateUnmarshalJSON(GoClientOptionsProvider.GENERATE_UNMARSHAL_JSON_VALUE);
         verify(clientCodegen).setUseDefaultValuesForRequiredVars(GoClientOptionsProvider.USE_DEFAULT_VALUES_FOR_REQUIRED_VARS_VALUE);
+        verify(clientCodegen).setEnumUnknownDefaultCase(Boolean.parseBoolean(GoClientOptionsProvider.ENUM_UNKNOWN_DEFAULT_CASE_VALUE));
     }
 }

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

@@ -40,6 +40,7 @@ public class GoClientOptionsProvider implements OptionsProvider {
     public static final boolean GENERATE_MARSHAL_JSON_VALUE = true;
     public static final boolean GENERATE_UNMARSHAL_JSON_VALUE = true;
     public static final boolean USE_DEFAULT_VALUES_FOR_REQUIRED_VARS_VALUE = true;
+    public static final String ENUM_UNKNOWN_DEFAULT_CASE_VALUE = "false";
 
     @Override
     public String getLanguage() {
@@ -66,6 +67,7 @@ public Map<String, String> createOptions() {
                 .put("generateInterfaces", "true")
                 .put("structPrefix", "true")
                 .put(CodegenConstants.USE_DEFAULT_VALUES_FOR_REQUIRED_VARS, "true")
+                .put(CodegenConstants.ENUM_UNKNOWN_DEFAULT_CASE, ENUM_UNKNOWN_DEFAULT_CASE_VALUE)
                 .build();
     }
 

samples/openapi3/client/petstore/go/go-petstore/docs/EnumClass.md

@@ -9,6 +9,8 @@
 
 * `XYZ` (value: `"(xyz)"`)
 
+* `UNKNOWN_DEFAULT_OPEN_API` (value: `"unknown_default_open_api"`)
+
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
 

samples/openapi3/client/petstore/go/go-petstore/docs/ExampleEnum.md

@@ -7,6 +7,8 @@
 
 * `EXAMPLE2` (value: `"example2"`)
 
+* `UNKNOWN_DEFAULT_OPEN_API` (value: `"unknown_default_open_api"`)
+
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
 

samples/openapi3/client/petstore/go/go-petstore/docs/OuterEnum.md

@@ -9,6 +9,8 @@
 
 * `SHIPPED` (value: `"delivered"`)
 
+* `UNKNOWN_DEFAULT_OPEN_API` (value: `"unknown_default_open_api"`)
+
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)