[elm][haskell-servant] Fix issue 3256 (OpenAPITools#3262)

* [elm] fix empty operation exception (OpenAPITools#3256)

* [haskell-servant] fix empty operation type (OpenAPITools#3256)

* [elm][haskell-servant] update samples

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

@@ -446,7 +446,9 @@ public Map<String, Object> postProcessOperationsWithModels(Map<String, Object> o
                 op.path = ("\"" + path + "\"").replaceAll(" \\+\\+ \"\"", "");
             } else {
                 final List<String> paths = Arrays.asList(op.path.substring(1).split("/"));
-                String path = paths.stream().map(str -> str.charAt(0) == '{' ? str : "\"" + str + "\"").collect(Collectors.joining(", "));
+                String path = paths.stream()
+                        .map(str -> str.startsWith("{") && str.endsWith("}") ? str : "\"" + str + "\"")
+                        .collect(Collectors.joining(", "));
                 for (CodegenParameter param : op.pathParams) {
                     String str = paramToString("params", param, false, null);
                     path = path.replace("{" + param.paramName + "}", str);

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

@@ -411,6 +411,11 @@ private List<String> pathToServantRoute(String path, List<CodegenParameter> path
         for (CodegenParameter param : pathParams) {
             captureTypes.put(param.baseName, param.dataType);
         }
+
+        // Properly handle root-only routes (#3256)
+        if (path.contentEquals("/")) {
+            return new ArrayList<>();
+        }
 
         // Cut off the leading slash, if it is present.
         if (path.startsWith("/")) {

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

@@ -0,0 +1,108 @@
+/*
+ * Copyright 2019 OpenAPI-Generator Contributors (https://openapi-generator.tech)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openapitools.codegen.elm;
+
+import static com.google.common.collect.Lists.newArrayList;
+import static java.util.Collections.emptyList;
+import static org.testng.Assert.assertEquals;
+import static org.testng.Assert.assertNotNull;
+import static org.testng.Assert.assertTrue;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.openapitools.codegen.ClientOptInput;
+import org.openapitools.codegen.ClientOpts;
+import org.openapitools.codegen.CodegenOperation;
+import org.openapitools.codegen.MockDefaultGenerator;
+import org.openapitools.codegen.languages.ElmClientCodegen;
+import org.testng.annotations.Test;
+
+import com.google.common.collect.ImmutableMap;
+
+import io.swagger.parser.OpenAPIParser;
+import io.swagger.v3.oas.models.OpenAPI;
+import io.swagger.v3.parser.core.models.ParseOptions;
+
+public class ElmClientCodegenTest {
+
+    @Test
+    public void testPostProcessRootEndpoint() {
+        // given
+        final ElmClientCodegen codegen = new ElmClientCodegen();
+
+        CodegenOperation rootOp = new CodegenOperation() {{ path = "/"; }};
+        List<CodegenOperation> ops = newArrayList(rootOp);
+
+        Map<String, Object> operations = new HashMap<>();
+        operations.put("operations", ImmutableMap
+                .<String, Object>builder()
+                .put("operation", ops)
+                .build());
+
+        // when
+        Map<String, Object> result = codegen.postProcessOperationsWithModels(operations, emptyList());
+
+        // then
+        assertEquals(result.size(), 2);
+        assertTrue(result.containsKey("operations"));
+        assertTrue(result.containsKey("elmImports"));
+
+        assertEquals(rootOp.path, "\"\"");
+    }
+
+    @Test
+    public void testGenerateRootEndpoint() throws IOException {
+        // given
+        File output = Files.createTempDirectory("test").toFile().getCanonicalFile();
+        output.deleteOnExit();
+        String outputPath = output.getAbsolutePath().replace('\\', '/');
+
+        final ElmClientCodegen codegen = new ElmClientCodegen();
+        codegen.setOutputDir(output.getAbsolutePath());
+
+        OpenAPI openAPI = new OpenAPIParser()
+                .readLocation("src/test/resources/3_0/rootOperation.yaml", null, new ParseOptions())
+                .getOpenAPI();
+
+        ClientOpts opts = new ClientOpts();
+
+        ClientOptInput input = new ClientOptInput();
+        input.setOpenAPI(openAPI);
+        input.setConfig(codegen);
+        input.setOpts(opts);
+
+        // when
+        MockDefaultGenerator generator = new MockDefaultGenerator();
+        generator.opts(input).generate();
+
+        // then
+        assertFileContains(generator, outputPath + "/src/Request/Default.elm", "rootGet", "[\"\"]");
+    }
+
+    private static void assertFileContains(MockDefaultGenerator generator, String file, String... expected) {
+        String content = generator.getFiles().get(file);
+        assertNotNull(content, "The file \"" + file + "\" was not generated");
+        for (String line : expected) {
+            assertTrue(content.contains(line), "The file \"" + file + "\" does not contain \"" + line + "\"");
+        }
+    }
+}

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

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2019 OpenAPI-Generator Contributors (https://openapi-generator.tech)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openapitools.codegen.haskellservant;
+
+import static org.testng.Assert.assertFalse;
+import static org.testng.Assert.assertNotNull;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.util.Arrays;
+
+import org.openapitools.codegen.ClientOptInput;
+import org.openapitools.codegen.ClientOpts;
+import org.openapitools.codegen.MockDefaultGenerator;
+import org.openapitools.codegen.languages.HaskellServantCodegen;
+import org.testng.annotations.Test;
+
+import io.swagger.parser.OpenAPIParser;
+import io.swagger.v3.oas.models.OpenAPI;
+import io.swagger.v3.parser.core.models.ParseOptions;
+
+public class HaskellServantCodegenTest {
+
+    @Test
+    public void testGenerateRootEndpoint() throws IOException {
+        // given
+        File output = Files.createTempDirectory("test").toFile().getCanonicalFile();
+        output.deleteOnExit();
+        String outputPath = output.getAbsolutePath().replace('\\', '/');
+
+        final HaskellServantCodegen codegen = new HaskellServantCodegen();
+        codegen.setOutputDir(output.getAbsolutePath());
+
+        OpenAPI openAPI = new OpenAPIParser()
+                .readLocation("src/test/resources/3_0/rootOperation.yaml", null, new ParseOptions())
+                .getOpenAPI();
+
+        ClientOpts opts = new ClientOpts();
+
+        ClientOptInput input = new ClientOptInput();
+        input.setOpenAPI(openAPI);
+        input.setConfig(codegen);
+        input.setOpts(opts);
+
+        // when
+        MockDefaultGenerator generator = new MockDefaultGenerator();
+        generator.opts(input).generate();
+
+        // then
+        assertFileNotContains(generator, outputPath + "/lib/RootOperation/API.hs", "\"\" :>");
+    }
+
+    private static void assertFileNotContains(MockDefaultGenerator generator, String file, String... expected) {
+        String content = generator.getFiles().get(file);
+        assertNotNull(content, "The file \"" + file + "\" was not generated");
+        for (String line : expected) {
+            assertFalse(content.contains(line), "The file \"" + file + "\" contains \"" + line + "\"");
+        }
+    }
+}

modules/openapi-generator/src/test/resources/3_0/rootOperation.yaml

@@ -0,0 +1,13 @@
+openapi: 3.0.0
+
+info:
+  title: Root Operation
+  version: 1.0.0
+
+paths:
+  /:
+    get:
+      summary: Simple root endpoint
+      responses:
+        204:
+          description: No response body

samples/client/petstore/elm-0.18/.openapi-generator/VERSION

@@ -1 +1 @@
-4.0.0-SNAPSHOT
+4.0.3-SNAPSHOT

samples/client/petstore/elm-0.18/src/Data/ApiResponse.elm

@@ -2,7 +2,7 @@
    OpenAPI Petstore
    This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
 
-   OpenAPI spec version: 1.0.0
+   The version of the OpenAPI document: 1.0.0
 
    NOTE: This file is auto generated by the openapi-generator.
    https://github.com/openapitools/openapi-generator.git
@@ -21,9 +21,9 @@ import Json.Encode as Encode
 {-| Describes the result of uploading an image resource
 -}
 type alias ApiResponse =
-    { code : Maybe Int
-    , type_ : Maybe String
-    , message : Maybe String
+    { code : Maybe (Int)
+    , type_ : Maybe (String)
+    , message : Maybe (String)
     }
 
 
@@ -35,10 +35,14 @@ decoder =
         |> optional "message" (Decode.nullable Decode.string) Nothing
 
 
+
 encode : ApiResponse -> Encode.Value
 encode model =
     Encode.object
         [ ( "code", Maybe.withDefault Encode.null (Maybe.map Encode.int model.code) )
         , ( "type", Maybe.withDefault Encode.null (Maybe.map Encode.string model.type_) )
         , ( "message", Maybe.withDefault Encode.null (Maybe.map Encode.string model.message) )
+
         ]
+
+

samples/client/petstore/elm-0.18/src/Data/Category.elm

@@ -2,7 +2,7 @@
    OpenAPI Petstore
    This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
 
-   OpenAPI spec version: 1.0.0
+   The version of the OpenAPI document: 1.0.0
 
    NOTE: This file is auto generated by the openapi-generator.
    https://github.com/openapitools/openapi-generator.git
@@ -21,8 +21,8 @@ import Json.Encode as Encode
 {-| A category for a pet
 -}
 type alias Category =
-    { id : Maybe Int
-    , name : Maybe String
+    { id : Maybe (Int)
+    , name : Maybe (String)
     }
 
 
@@ -33,9 +33,13 @@ decoder =
         |> optional "name" (Decode.nullable Decode.string) Nothing
 
 
+
 encode : Category -> Encode.Value
 encode model =
     Encode.object
         [ ( "id", Maybe.withDefault Encode.null (Maybe.map Encode.int model.id) )
         , ( "name", Maybe.withDefault Encode.null (Maybe.map Encode.string model.name) )
+
         ]
+
+

samples/client/petstore/elm-0.18/src/Data/Order_.elm

@@ -2,7 +2,7 @@
    OpenAPI Petstore
    This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
 
-   OpenAPI spec version: 1.0.0
+   The version of the OpenAPI document: 1.0.0
 
    NOTE: This file is auto generated by the openapi-generator.
    https://github.com/openapitools/openapi-generator.git
@@ -22,12 +22,12 @@ import Json.Encode as Encode
 {-| An order for a pets from the pet store
 -}
 type alias Order_ =
-    { id : Maybe Int
-    , petId : Maybe Int
-    , quantity : Maybe Int
-    , shipDate : Maybe DateTime
-    , status : Maybe Status
-    , complete : Maybe Bool
+    { id : Maybe (Int)
+    , petId : Maybe (Int)
+    , quantity : Maybe (Int)
+    , shipDate : Maybe (DateTime)
+    , status : Maybe (Status)
+    , complete : Maybe (Bool)
     }
 
 
@@ -37,6 +37,7 @@ type Status
     | Delivered
 
 
+
 decoder : Decoder Order_
 decoder =
     decode Order_
@@ -48,6 +49,7 @@ decoder =
         |> optional "complete" (Decode.nullable Decode.bool) (Just False)
 
 
+
 encode : Order_ -> Encode.Value
 encode model =
     Encode.object
@@ -57,9 +59,11 @@ encode model =
         , ( "shipDate", Maybe.withDefault Encode.null (Maybe.map DateTime.encode model.shipDate) )
         , ( "status", Maybe.withDefault Encode.null (Maybe.map encodeStatus model.status) )
         , ( "complete", Maybe.withDefault Encode.null (Maybe.map Encode.bool model.complete) )
+
         ]
 
 
+
 statusDecoder : Decoder Status
 statusDecoder =
     Decode.string
@@ -80,6 +84,7 @@ statusDecoder =
             )
 
 
+
 encodeStatus : Status -> Encode.Value
 encodeStatus model =
     case model of
@@ -91,3 +96,6 @@ encodeStatus model =
 
         Delivered ->
             Encode.string "delivered"
+
+
+