Make yaml serialization deterministic

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

@@ -22,7 +22,6 @@
 import com.samskivert.mustache.Mustache.Compiler;
 
 import io.swagger.v3.core.util.Json;
-import io.swagger.v3.core.util.Yaml;
 import io.swagger.v3.oas.models.OpenAPI;
 import io.swagger.v3.oas.models.Operation;
 import io.swagger.v3.oas.models.headers.Header;
@@ -47,6 +46,7 @@
 import org.apache.commons.lang3.StringEscapeUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.openapitools.codegen.examples.ExampleGenerator;
+import org.openapitools.codegen.serializer.SerializerUtils;
 import org.openapitools.codegen.utils.ModelUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -4336,12 +4336,9 @@ public void generateJSONSpecFile(Map<String, Object> objs) {
      */
     public void generateYAMLSpecFile(Map<String, Object> objs) {
         OpenAPI openAPI = (OpenAPI) objs.get("openAPI");
-        if (openAPI != null) {
-            try {
-                objs.put("openapi-yaml", Yaml.mapper().writeValueAsString(openAPI));
-            } catch (JsonProcessingException e) {
-                LOGGER.error(e.getMessage(), e);
-            }
+        String yaml = SerializerUtils.toYamlString(openAPI);
+        if(yaml != null) {
+            objs.put("openapi-yaml", yaml);
         }
     }
 

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

@@ -0,0 +1,49 @@
+package org.openapitools.codegen.serializer;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.SerializerProvider;
+
+import io.swagger.v3.oas.models.OpenAPI;
+
+import java.io.IOException;
+import java.util.Map.Entry;
+
+public class OpenAPISerializer extends JsonSerializer<OpenAPI> {
+
+    @Override
+    public void serialize(OpenAPI value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
+        if (value != null) {
+            gen.writeStartObject();
+            gen.writeStringField("openapi", value.getOpenapi());
+            if(value.getInfo() != null) {
+                gen.writeObjectField("info", value.getInfo());
+            }
+            if(value.getExternalDocs() != null) {
+                gen.writeObjectField("externalDocs", value.getExternalDocs());
+            }
+            if(value.getServers() != null) {
+                gen.writeObjectField("servers", value.getServers());
+            }
+            if(value.getSecurity() != null) {
+                gen.writeObjectField("security", value.getSecurity());
+            }
+            if(value.getTags() != null) {
+                gen.writeObjectField("tags", value.getTags());
+            }
+            if(value.getPaths() != null) {
+                gen.writeObjectField("paths", value.getPaths());
+            }
+            if(value.getComponents() != null) {
+                gen.writeObjectField("components", value.getComponents());
+            }
+            if(value.getExtensions() != null) {
+                for (Entry<String, Object> e : value.getExtensions().entrySet()) {
+                    gen.writeObjectField(e.getKey(), e.getValue());
+                }
+            }
+            gen.writeEndObject();
+        }
+    }
+
+}

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

@@ -0,0 +1,34 @@
+package org.openapitools.codegen.serializer;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.MapperFeature;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+
+import io.swagger.v3.core.util.Yaml;
+import io.swagger.v3.oas.models.OpenAPI;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class SerializerUtils {
+    private static final Logger LOGGER = LoggerFactory.getLogger(SerializerUtils.class);
+
+    public static String toYamlString(OpenAPI openAPI) {
+        if(openAPI == null) {
+            return null;
+        }
+
+        SimpleModule module = new SimpleModule("OpenAPIModule");
+        module.addSerializer(OpenAPI.class, new OpenAPISerializer());
+        try {
+            return Yaml.mapper()
+                    .registerModule(module)
+                    .configure(MapperFeature.SORT_PROPERTIES_ALPHABETICALLY, true)
+                    .writeValueAsString(openAPI)
+                    .replace("\r\n", "\n");
+        } catch (JsonProcessingException e) {
+            LOGGER.warn("Can not create yaml content", e);
+        }
+        return null;
+    }
+}

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

@@ -0,0 +1,123 @@
+package org.openapitools.codegen.serializer;
+
+import static org.testng.Assert.assertEquals;
+
+import io.swagger.v3.oas.models.Components;
+import io.swagger.v3.oas.models.ExternalDocumentation;
+import io.swagger.v3.oas.models.OpenAPI;
+import io.swagger.v3.oas.models.Operation;
+import io.swagger.v3.oas.models.PathItem;
+import io.swagger.v3.oas.models.info.Info;
+import io.swagger.v3.oas.models.media.ObjectSchema;
+import io.swagger.v3.oas.models.media.StringSchema;
+import io.swagger.v3.oas.models.responses.ApiResponse;
+import io.swagger.v3.oas.models.responses.ApiResponses;
+import io.swagger.v3.oas.models.security.SecurityRequirement;
+import io.swagger.v3.oas.models.servers.Server;
+import io.swagger.v3.oas.models.tags.Tag;
+
+import org.testng.annotations.Test;
+
+import java.util.Arrays;
+
+public class SerializerUtilsTest {
+
+    @Test
+    public void testToYamlStringCompleteExample() throws Exception {
+        OpenAPI openAPI = new OpenAPI();
+        openAPI.setInfo(new Info().title("Some title").description("Some description"));
+        openAPI.setExternalDocs(new ExternalDocumentation().url("http://abcdef.com").description("a-description"));
+        openAPI.setServers(Arrays.asList(
+                new Server().url("http://www.server1.com").description("first server"),
+                new Server().url("http://www.server2.com").description("second server")
+            ));
+        openAPI.setSecurity(Arrays.asList(
+                new SecurityRequirement().addList("some_auth", Arrays.asList("write", "read"))
+            ));
+        openAPI.setTags(Arrays.asList(
+                new Tag().name("tag1").description("some 1 description"),
+                new Tag().name("tag2").description("some 2 description"),
+                new Tag().name("tag3").description("some 3 description")
+            ));
+        openAPI.path("/ping/pong", new PathItem().get(new Operation()
+                .description("Some description")
+                .operationId("pingOp")
+                .responses(new ApiResponses().addApiResponse("200", new ApiResponse().description("Ok")))));
+        openAPI.components(new Components().addSchemas("SomeObject", new ObjectSchema().description("An Obj").addProperties("id", new StringSchema())));
+        openAPI.addExtension("x-custom", "value1");
+        openAPI.addExtension("x-other", "value2");
+
+        String content = SerializerUtils.toYamlString(openAPI);
+        String expected = "openapi: 3.0.1\n" + 
+               "info:\n" + 
+               "  description: Some description\n" + 
+               "  title: Some title\n" + 
+               "externalDocs:\n" + 
+               "  description: a-description\n" + 
+               "  url: http://abcdef.com\n" + 
+               "servers:\n" + 
+               "- description: first server\n" + 
+               "  url: http://www.server1.com\n" + 
+               "- description: second server\n" + 
+               "  url: http://www.server2.com\n" + 
+               "security:\n" + 
+               "- some_auth:\n" + 
+               "  - write\n" + 
+               "  - read\n" + 
+               "tags:\n" + 
+               "- description: some 1 description\n" + 
+               "  name: tag1\n" + 
+               "- description: some 2 description\n" + 
+               "  name: tag2\n" + 
+               "- description: some 3 description\n" + 
+               "  name: tag3\n" + 
+               "paths:\n" + 
+               "  /ping/pong:\n" + 
+               "    get:\n" + 
+               "      description: Some description\n" + 
+               "      operationId: pingOp\n" + 
+               "      responses:\n" + 
+               "        200:\n" + 
+               "          description: Ok\n" + 
+               "components:\n" + 
+               "  schemas:\n" + 
+               "    SomeObject:\n" + 
+               "      description: An Obj\n" + 
+               "      properties:\n" + 
+               "        id:\n" + 
+               "          type: string\n" + 
+               "      type: object\n" + 
+               "x-other: value2\n" + 
+               "x-custom: value1\n";
+        assertEquals(content, expected);
+    }
+
+    @Test
+    public void testToYamlStringMinimalExample() throws Exception {
+        OpenAPI openAPI = new OpenAPI();
+        openAPI.setInfo(new Info().title("Some title"));
+        openAPI.setServers(Arrays.asList(
+                new Server().url("http://www.server1.com")
+            ));
+        openAPI.path("/ping/pong", new PathItem().get(new Operation()
+                .description("Some description")
+                .operationId("pingOp")
+                .responses(new ApiResponses().addApiResponse("200", new ApiResponse().description("Ok")))));
+
+        String content = SerializerUtils.toYamlString(openAPI);
+        String expected = "openapi: 3.0.1\n" + 
+                "info:\n" + 
+                "  title: Some title\n" + 
+                "servers:\n" + 
+                "- url: http://www.server1.com\n" + 
+                "paths:\n" + 
+                "  /ping/pong:\n" + 
+                "    get:\n" + 
+                "      description: Some description\n" + 
+                "      operationId: pingOp\n" + 
+                "      responses:\n" + 
+                "        200:\n" + 
+                "          description: Ok\n"; 
+        assertEquals(content, expected);
+    }
+}

samples/server/petstore/java-inflector/.openapi-generator/VERSION

@@ -1 +1 @@
-3.0.0-SNAPSHOT
+3.0.1-SNAPSHOT