fix #7325 kotlin-spring fix reactive delegate pattern combination (#8867)

* #7325 kotlin-spring remove exchange field from reactive delegate pattern

* #7325 remove examples from kotlin-spring reactive delegate and add missing import

* #7325 add test assertions

* fix swagger spec in test

modules/openapi-generator/src/main/resources/kotlin-spring/apiDelegate.mustache

@@ -8,6 +8,7 @@ import org.springframework.http.ResponseEntity
 import org.springframework.web.context.request.NativeWebRequest
 import org.springframework.core.io.Resource
 {{#reactive}}
+import kotlinx.coroutines.flow.Flow
 import org.springframework.web.server.ServerWebExchange
 import reactor.core.publisher.Flux
 import reactor.core.publisher.Mono
@@ -32,7 +33,7 @@ interface {{classname}}Delegate {
     /**
      * @see {{classname}}#{{operationId}}
      */
-    fun {{operationId}}({{#allParams}}{{paramName}}: {{^isFile}}{{>optionalDataType}}{{/isFile}}{{#isFile}}Resource?{{/isFile}}{{^-last}},
+    {{#reactive}}{{^isArray}}suspend {{/isArray}}{{/reactive}}fun {{operationId}}({{#allParams}}{{paramName}}: {{^isFile}}{{>optionalDataType}}{{/isFile}}{{#isFile}}Resource?{{/isFile}}{{^-last}},
         {{/-last}}{{/allParams}}): {{#responseWrapper}}{{.}}<{{/responseWrapper}}ResponseEntity<{{>returnTypes}}>{{#responseWrapper}}>{{/responseWrapper}} {
         {{>methodBody}}
     }

modules/openapi-generator/src/main/resources/kotlin-spring/apiInterface.mustache

@@ -83,7 +83,7 @@ interface {{classname}} {
         return {{>returnValue}}
         {{/isDelegate}}
         {{#isDelegate}}
-        return getDelegate().{{operationId}}({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}}{{#reactive}}{{#hasParams}}, {{/hasParams}}exchange{{/reactive}});
+        return getDelegate().{{operationId}}({{#allParams}}{{paramName}}{{^-last}}, {{/-last}}{{/allParams}});
         {{/isDelegate}}
     }
 {{/operation}}

modules/openapi-generator/src/main/resources/kotlin-spring/methodBody.mustache

@@ -1,3 +1,4 @@
+{{^reactive}}
 {{#examples}}
     {{#-first}}
         {{#async}}
@@ -21,3 +22,7 @@ return CompletableFuture.supplyAsync(()-> {
 {{^examples}}
 return {{#async}}CompletableFuture.completedFuture({{/async}}ResponseEntity({{#returnSuccessCode}}HttpStatus.OK{{/returnSuccessCode}}{{^returnSuccessCode}}HttpStatus.NOT_IMPLEMENTED{{/returnSuccessCode}})
 {{/examples}}
+{{/reactive}}
+{{#reactive}}
+return ResponseEntity({{#returnSuccessCode}}HttpStatus.OK{{/returnSuccessCode}}{{^returnSuccessCode}}HttpStatus.NOT_IMPLEMENTED{{/returnSuccessCode}})
+{{/reactive}}

modules/openapi-generator/src/test/java/org/openapitools/codegen/kotlin/spring/KotlinSpringServerCodegenTest.java

@@ -1,9 +1,14 @@
 package org.openapitools.codegen.kotlin.spring;
 
 import com.google.common.collect.testing.Helpers;
-
+import io.swagger.v3.oas.models.OpenAPI;
+import io.swagger.v3.oas.models.info.Info;
+import io.swagger.v3.oas.models.servers.Server;
 import org.apache.commons.io.FileUtils;
-import org.openapitools.codegen.*;
+import org.openapitools.codegen.ClientOptInput;
+import org.openapitools.codegen.CodegenConstants;
+import org.openapitools.codegen.DefaultGenerator;
+import org.openapitools.codegen.TestUtils;
 import org.openapitools.codegen.kotlin.KotlinTestUtils;
 import org.openapitools.codegen.languages.KotlinSpringServerCodegen;
 import org.testng.Assert;
@@ -11,12 +16,12 @@ import org.testng.annotations.Test;
 
 import java.io.File;
 import java.nio.file.Files;
+import java.nio.file.Paths;
 import java.util.Collections;
 import java.util.List;
 
-import io.swagger.v3.oas.models.OpenAPI;
+import static org.openapitools.codegen.TestUtils.assertFileContains;
-import io.swagger.v3.oas.models.info.Info;
+import static org.openapitools.codegen.TestUtils.assertFileNotContains;
-import io.swagger.v3.oas.models.servers.Server;
 
 public class KotlinSpringServerCodegenTest {
 
@@ -203,4 +208,49 @@ public class KotlinSpringServerCodegenTest {
             new File(output, "src/main/kotlin/org/openapitools/api/TestV2ApiDelegate.kt")
         );
     }
+
+    @Test(description = "test delegate reactive with tags")
+    public void delegateReactiveWithTags() throws Exception {
+        File output = Files.createTempDirectory("test").toFile().getCanonicalFile(); //may be move to /build
+        KotlinSpringServerCodegen codegen = new KotlinSpringServerCodegen();
+        codegen.setOutputDir(output.getAbsolutePath());
+        codegen.additionalProperties().put(KotlinSpringServerCodegen.DELEGATE_PATTERN, true);
+        codegen.additionalProperties().put(KotlinSpringServerCodegen.REACTIVE, true);
+        codegen.additionalProperties().put(KotlinSpringServerCodegen.USE_TAGS, true);
+
+        List<File> files = new DefaultGenerator()
+                .opts(
+                        new ClientOptInput()
+                                .openAPI(TestUtils.parseSpec("src/test/resources/3_0/kotlin/issue7325-use-delegate-reactive-tags-kotlin.yaml"))
+                                .config(codegen)
+                )
+                .generate();
+
+        Helpers.assertContainsAllOf(files,
+                new File(output, "src/main/kotlin/org/openapitools/api/TestV1Api.kt"),
+                new File(output, "src/main/kotlin/org/openapitools/api/TestV1ApiController.kt"),
+                new File(output, "src/main/kotlin/org/openapitools/api/TestV1ApiDelegate.kt"),
+                new File(output, "src/main/kotlin/org/openapitools/api/TestV2Api.kt"),
+                new File(output, "src/main/kotlin/org/openapitools/api/TestV2ApiController.kt"),
+                new File(output, "src/main/kotlin/org/openapitools/api/TestV2ApiDelegate.kt")
+        );
+
+        assertFileContains(Paths.get(output + "/src/main/kotlin/org/openapitools/api/TestV1Api.kt"),
+                "suspend fun");
+        assertFileNotContains(Paths.get(output + "/src/main/kotlin/org/openapitools/api/TestV1Api.kt"),
+                "exchange");
+        assertFileContains(Paths.get(output + "/src/main/kotlin/org/openapitools/api/TestV1ApiDelegate.kt"),
+                "suspend fun");
+        assertFileNotContains(Paths.get(output + "/src/main/kotlin/org/openapitools/api/TestV1ApiDelegate.kt"),
+                "ApiUtil");
+
+        assertFileContains(Paths.get(output + "/src/main/kotlin/org/openapitools/api/TestV2Api.kt"),
+                "import kotlinx.coroutines.flow.Flow", "ResponseEntity<Flow<kotlin.String>>");
+        assertFileNotContains(Paths.get(output + "/src/main/kotlin/org/openapitools/api/TestV2Api.kt"),
+                "exchange");
+        assertFileContains(Paths.get(output + "/src/main/kotlin/org/openapitools/api/TestV2ApiDelegate.kt"),
+                "import kotlinx.coroutines.flow.Flow");
+        assertFileNotContains(Paths.get(output + "/src/main/kotlin/org/openapitools/api/TestV2ApiDelegate.kt"),
+                "suspend fun", "ApiUtil");
+    }
 }

modules/openapi-generator/src/test/resources/3_0/kotlin/issue7325-use-delegate-reactive-tags-kotlin.yaml

@@ -0,0 +1,35 @@
+openapi: "3.0.1"
+info:
+  title: test
+  version: "1.0"
+
+paths:
+
+  /api/v1/test/{id}:
+    get:
+      tags: [Test v1]
+      operationId: test1
+      parameters:
+        - name: id
+          in: path
+          schema:
+            type: string
+      responses:
+        200:
+          description: OK
+
+  /api/v2/test:
+    get:
+      tags: [Test v2]
+      operationId: test2
+      responses:
+        200:
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  type: string
+
+