[protobuf-schema] Use snake_case for protobuf fields, UPPER_SNAKE_CASE for enums. (#20696)

* protobuf enum prefix use upper underscore

Add json name parameters and change parameter field name to snake case

* rerun generate-samples.sh

* Add CI test

* rebase master

---------

Co-authored-by: xil <[email protected]>

Author: lucy66hw

.github/workflows/samples-protobuf.yaml

@@ -0,0 +1,38 @@
+name: Samples Protobuf
+on:
+  push:
+    paths:
+      - .github/workflows/samples-protobuf.yaml
+      - samples/config/petstore/protobuf-schema/**
+      - samples/config/petstore/protobuf-schema-config/**
+  pull_request:
+    paths:
+      - .github/workflows/samples-protobuf.yaml
+      - samples/config/petstore/protobuf-schema/**
+      - samples/config/petstore/protobuf-schema-config/**
+jobs:
+  build:
+    name: Build Protobuf Client
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        sample:
+          - 'samples/config/petstore/protobuf-schema/'
+          - 'samples/config/petstore/protobuf-schema-config/'
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install Protocol Buffers Compiler
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y protobuf-compiler
+      - name: Generate Protobuf Schema
+        working-directory: ${{ matrix.sample }}
+        run: |
+          mkdir out
+          protoc --proto_path=. --cpp_out=out models/*.proto services/*.proto
+      - name: Verify Generated Files
+        working-directory: ${{ matrix.sample }}
+        run: |
+          ls -l out/models
+          ls -l out/services

bin/configs/protobuf-schema-config.yaml

@@ -0,0 +1,9 @@
+generatorName: protobuf-schema
+outputDir: samples/config/petstore/protobuf-schema-config
+inputSpec: modules/openapi-generator/src/test/resources/3_0/protobuf/petstore.yaml
+templateDir: modules/openapi-generator/src/main/resources/protobuf-schema
+additionalProperties:
+  packageName: petstore
+  addJsonNameAnnotation: true
+  numberedFieldNumberList: true
+  startEnumsWithUnspecified: true

docs/generators/protobuf-schema.md

@@ -18,6 +18,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 
 | Option | Description | Values | Default |
 | ------ | ----------- | ------ | ------- |
+|addJsonNameAnnotation|Append "json_name" annotation to message field when the specification name differs from the protobuf field name| |false|
 |numberedFieldNumberList|Field numbers in order.| |false|
 |startEnumsWithUnspecified|Introduces "UNSPECIFIED" as the first element of enumerations.| |false|
 

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

@@ -38,6 +38,7 @@
 import java.util.*;
 import java.util.Map.Entry;
 import java.util.regex.Pattern;
+import com.google.common.base.CaseFormat;
 
 import static org.openapitools.codegen.utils.StringUtils.camelize;
 import static org.openapitools.codegen.utils.StringUtils.underscore;
@@ -52,6 +53,8 @@ public class ProtobufSchemaCodegen extends DefaultCodegen implements CodegenConf
 
     public static final String START_ENUMS_WITH_UNSPECIFIED = "startEnumsWithUnspecified";
 
+    public static final String ADD_JSON_NAME_ANNOTATION = "addJsonNameAnnotation";
+
     private final Logger LOGGER = LoggerFactory.getLogger(ProtobufSchemaCodegen.class);
 
     @Setter protected String packageName = "openapitools";
@@ -60,11 +63,18 @@ public class ProtobufSchemaCodegen extends DefaultCodegen implements CodegenConf
 
     private boolean startEnumsWithUnspecified = false;
 
+    private boolean addJsonNameAnnotation = false;
+
     @Override
     public CodegenType getTag() {
         return CodegenType.SCHEMA;
     }
 
+    @Override
+    public String toEnumName(CodegenProperty property) {
+        return StringUtils.capitalize(property.name);
+    }
+
     @Override
     public String getName() {
         return "protobuf-schema";
@@ -163,6 +173,7 @@ public ProtobufSchemaCodegen() {
 
         addSwitch(NUMBERED_FIELD_NUMBER_LIST, "Field numbers in order.", numberedFieldNumberList);
         addSwitch(START_ENUMS_WITH_UNSPECIFIED, "Introduces \"UNSPECIFIED\" as the first element of enumerations.", startEnumsWithUnspecified);
+        addSwitch(ADD_JSON_NAME_ANNOTATION, "Append \"json_name\" annotation to message field when the specification name differs from the protobuf field name", addJsonNameAnnotation);
     }
 
     @Override
@@ -197,6 +208,10 @@ public void processOpts() {
             this.startEnumsWithUnspecified = convertPropertyToBooleanAndWriteBack(START_ENUMS_WITH_UNSPECIFIED);
         }
 
+        if (additionalProperties.containsKey(this.ADD_JSON_NAME_ANNOTATION)) {
+            this.addJsonNameAnnotation = convertPropertyToBooleanAndWriteBack(ADD_JSON_NAME_ANNOTATION);
+        }
+
         supportingFiles.add(new SupportingFile("README.mustache", "", "README.md"));
     }
 
@@ -226,7 +241,7 @@ public String toOperationId(String operationId) {
     public void addEnumValuesPrefix(Map<String, Object> allowableValues, String prefix) {
         if (allowableValues.containsKey("enumVars")) {
             List<Map<String, Object>> enumVars = (List<Map<String, Object>>) allowableValues.get("enumVars");
-
+            prefix = CaseFormat.LOWER_CAMEL.to(CaseFormat.UPPER_UNDERSCORE, prefix);
             for (Map<String, Object> value : enumVars) {
                 String name = (String) value.get("name");
                 value.put("name", prefix + "_" + name);
@@ -338,6 +353,10 @@ public ModelsMap postProcessModels(ModelsMap objs) {
                         var.vendorExtensions.putIfAbsent("x-protobuf-index", "Generated field number is in reserved range (19000, 19999)");
                     }
                 }
+
+                if (addJsonNameAnnotation && !var.baseName.equals(var.name)) {
+                    var.vendorExtensions.put("x-protobuf-json-name", var.baseName);
+                }
             }
         }
         return objs;
@@ -493,10 +512,38 @@ public String toModelFilename(String name) {
     }
 
     @Override
-    public String toVarName(final String name) {
+    public String toVarName(String name) {
+        if (nameMapping.containsKey(name)) {
+            return nameMapping.get(name);
+        }
+        // sanitize name
+        name = sanitizeName(name); // FIXME: a parameter should not be assigned. Also declare the methods parameters as 'final'.
+
+        // if it's all upper case, convert to lower case
+        if (name.matches("^[A-Z_]*$")) {
+            name = name.toLowerCase(Locale.ROOT);
+        }
+
+        // underscore the variable name
+        // petId => pet_id
+        name = underscore(name);
+
+        // remove leading underscore
+        name = name.replaceAll("^_*", "");
+
+        // for reserved word or word starting with number, append _
+        if (isReservedWord(name) || name.matches("^\\d.*")) {
+            name = escapeReservedWord(name);
+        }
+
         return name;
     }
 
+    @Override
+    public String toParamName(String name) {
+        return toVarName(name);
+    }
+
     @Override
     public String toModelName(String name) {
         name = sanitizeName(name); // FIXME: a parameter should not be assigned. Also declare the methods parameters as 'final'.
@@ -571,6 +618,10 @@ public OperationsMap postProcessOperationsWithModels(OperationsMap objs, List<Mo
                     }
                 }
 
+                if (addJsonNameAnnotation && !p.baseName.equals(p.paramName) && !p.isBodyParam) {
+                    p.vendorExtensions.put("x-protobuf-json-name", p.baseName);
+                }
+
                 p.vendorExtensions.putIfAbsent("x-protobuf-index", index);
                 index++;
             }
@@ -646,4 +697,5 @@ private boolean parentVarsContainsVar(List<CodegenProperty> parentVars, CodegenP
     public GeneratorLanguage generatorLanguage() {
         return GeneratorLanguage.PROTOBUF;
     }
+
 }

modules/openapi-generator/src/main/resources/protobuf-schema/api.mustache

@@ -30,7 +30,7 @@ message {{operationId}}Request {
   {{#description}}
   // {{{.}}}
   {{/description}}
-  {{#vendorExtensions.x-protobuf-type}}{{.}} {{/vendorExtensions.x-protobuf-type}}{{vendorExtensions.x-protobuf-data-type}} {{paramName}} = {{vendorExtensions.x-protobuf-index}};
+  {{#vendorExtensions.x-protobuf-type}}{{.}} {{/vendorExtensions.x-protobuf-type}}{{vendorExtensions.x-protobuf-data-type}} {{paramName}} = {{vendorExtensions.x-protobuf-index}}{{#vendorExtensions.x-protobuf-json-name}} [json_name="{{vendorExtensions.x-protobuf-json-name}}"]{{/vendorExtensions.x-protobuf-json-name}};
   {{/allParams}}
 
 }

modules/openapi-generator/src/main/resources/protobuf-schema/model.mustache

@@ -18,7 +18,7 @@ import public "{{{modelPackage}}}/{{{import}}}.proto";
   // {{{.}}}
   {{/description}}
   {{^isEnum}}
-  {{#vendorExtensions.x-protobuf-type}}{{{.}}} {{/vendorExtensions.x-protobuf-type}}{{{vendorExtensions.x-protobuf-data-type}}} {{{name}}} = {{vendorExtensions.x-protobuf-index}}{{#vendorExtensions.x-protobuf-packed}} [packed=true]{{/vendorExtensions.x-protobuf-packed}};
+  {{#vendorExtensions.x-protobuf-type}}{{{.}}} {{/vendorExtensions.x-protobuf-type}}{{{vendorExtensions.x-protobuf-data-type}}} {{{name}}} = {{vendorExtensions.x-protobuf-index}}{{#vendorExtensions.x-protobuf-packed}} [packed=true]{{/vendorExtensions.x-protobuf-packed}}{{#vendorExtensions.x-protobuf-json-name}} [json_name="{{vendorExtensions.x-protobuf-json-name}}"]{{/vendorExtensions.x-protobuf-json-name}};
   {{/isEnum}}
   {{#isEnum}}
   enum {{enumName}} {

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

@@ -91,6 +91,6 @@ public void modelTest() {
         final CodegenModel simpleName = codegen.fromModel("$DollarModel$", openAPI.getComponents().getSchemas().get("$DollarModel$"));
         Assert.assertEquals(simpleName.name, "$DollarModel$");
         Assert.assertEquals(simpleName.classname, "DollarModel");
-        Assert.assertEquals(simpleName.classVarName, "$DollarModel$");
+        Assert.assertEquals(simpleName.classVarName, "dollar_model");
     }
 }

modules/openapi-generator/src/test/resources/3_0/protobuf-schema/pet.proto

@@ -14,12 +14,12 @@ package openapitools;
 
 message Pet {
 
-  string petType = 140636936;
+  string pet_type = 482112090;
 
   string name = 3373707;
 
   string bark = 3016376;
 
-  bool lovesRocks = 499337491;
+  bool loves_rocks = 465093427;
 
 }

samples/config/petstore/protobuf-schema-config/.openapi-generator-ignore

@@ -0,0 +1,23 @@
+# OpenAPI Generator Ignore
+# Generated by openapi-generator https://github.com/openapitools/openapi-generator
+
+# Use this file to prevent files from being overwritten by the generator.
+# The patterns follow closely to .gitignore or .dockerignore.
+
+# As an example, the C# client generator defines ApiClient.cs.
+# You can make changes and tell OpenAPI Generator to ignore just this file by uncommenting the following line:
+#ApiClient.cs
+
+# You can match any string of characters against a directory, file or extension with a single asterisk (*):
+#foo/*/qux
+# The above matches foo/bar/qux and foo/baz/qux, but not foo/bar/baz/qux
+
+# You can recursively match patterns against a directory, file or extension with a double asterisk (**):
+#foo/**/qux
+# This matches foo/bar/qux, foo/baz/qux, and foo/bar/baz/qux
+
+# You can also negate patterns with an exclamation (!).
+# For example, you can ignore all files in a docs folder with the file extension .md:
+#docs/*.md
+# Then explicitly reverse the ignore rule for a single file:
+#!docs/README.md

samples/config/petstore/protobuf-schema-config/.openapi-generator/FILES

@@ -0,0 +1,11 @@
+README.md
+models/api_response.proto
+models/category.proto
+models/order.proto
+models/other_test.proto
+models/pet.proto
+models/tag.proto
+models/user.proto
+services/pet_service.proto
+services/store_service.proto
+services/user_service.proto