[typescript] fix: nullable enums should not serialize a null value to a string (#19540)

* fix: `nullable` enums should not serialize a `null` value to a string

* better solution?

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

Co-authored-by: Joscha Feth <joscha@feth.com>

* chore: Update circle_parallel.sh

---------

Co-authored-by: William Cheng <wing328hk@gmail.com>

CI/circle_parallel.sh

@@ -91,6 +91,7 @@ elif [ "$NODE_INDEX" = "3" ]; then
   #(cd samples/openapi3/client/petstore/typescript/tests/deno && mvn integration-test)
   (cd samples/openapi3/client/petstore/typescript/builds/browser && mvn integration-test)
   (cd samples/openapi3/client/petstore/typescript/tests/browser && mvn integration-test)
+  (cd samples/openapi3/client/petstore/typescript/builds/nullable-enum && mvn integration-test)
   (cd samples/client/petstore/typescript-fetch/builds/default && mvn integration-test)
   (cd samples/client/petstore/typescript-fetch/builds/es6-target && mvn integration-test)
   (cd samples/client/petstore/typescript-fetch/builds/with-npm-version && mvn integration-test)

bin/configs/typescript-consolidated-nullable-enum.yaml

@@ -0,0 +1,4 @@
+generatorName: typescript
+outputDir: samples/openapi3/client/petstore/typescript/builds/nullable-enum
+inputSpec: modules/openapi-generator/src/test/resources/3_0/typescript/19027-regression.yaml
+templateDir: modules/openapi-generator/src/main/resources/typescript

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

@@ -3949,6 +3949,12 @@ public class DefaultCodegen implements CodegenConfig {
             List<Object> _enum = p.getEnum();
             property._enum = new ArrayList<>();
             for (Object i : _enum) {
+                // raw null values in enums are unions for nullable
+                // atttributes, not actual enum values, so we remove them here
+                if (i == null) {
+                    property.isNullable = true;
+                    continue;
+                }
                 property._enum.add(String.valueOf(i));
             }
             property.isEnum = true;
@@ -6640,6 +6646,11 @@ public class DefaultCodegen implements CodegenConfig {
                 : 0;
 
         for (Object value : values) {
+            if (value == null) {
+                // raw null values in enums are unions for nullable
+                // atttributes, not actual enum values, so we remove them here
+                continue;
+            }
             Map<String, Object> enumVar = new HashMap<>();
             String enumName = truncateIdx == 0
                     ? String.valueOf(value)

modules/openapi-generator/src/test/resources/3_0/typescript/19027-regression.yaml

@@ -0,0 +1,31 @@
+openapi: 3.0.0
+info:
+  version: 1.0.0
+  title: Sample for uniqueItems
+servers:
+  - url: http://localhost:3000
+paths:
+  /unique-items:
+    get:
+      operationId: unique_items
+      responses:
+        200:
+          description: OK
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Response'
+components:
+  schemas:
+    Response:
+      type: object
+      properties:
+        enrichmentSource:
+          description: The source of the data in this Field (if it is enriched)
+          enum:
+            - "affinity-data"
+            - "dealroom"
+            - null
+          example: "affinity-data"
+          type: "string"
+          nullable: true

samples/openapi3/client/petstore/typescript/builds/nullable-enum/.gitignore

@@ -0,0 +1 @@
+dist

samples/openapi3/client/petstore/typescript/builds/nullable-enum/.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/openapi3/client/petstore/typescript/builds/nullable-enum/.openapi-generator/FILES

@@ -0,0 +1,24 @@
+.gitignore
+DefaultApi.md
+README.md
+apis/DefaultApi.ts
+apis/baseapi.ts
+apis/exception.ts
+auth/auth.ts
+configuration.ts
+git_push.sh
+http/http.ts
+http/isomorphic-fetch.ts
+index.ts
+middleware.ts
+models/ObjectSerializer.ts
+models/Response.ts
+models/all.ts
+package.json
+rxjsStub.ts
+servers.ts
+tsconfig.json
+types/ObjectParamAPI.ts
+types/ObservableAPI.ts
+types/PromiseAPI.ts
+util.ts

samples/openapi3/client/petstore/typescript/builds/nullable-enum/.openapi-generator/VERSION

@@ -0,0 +1 @@
+7.9.0-SNAPSHOT

samples/openapi3/client/petstore/typescript/builds/nullable-enum/DefaultApi.md

@@ -0,0 +1,57 @@
+# .DefaultApi
+
+All URIs are relative to *http://localhost:3000*
+
+Method | HTTP request | Description
+------------- | ------------- | -------------
+[**uniqueItems**](DefaultApi.md#uniqueItems) | **GET** /unique-items | 
+
+
+# **uniqueItems**
+> Response uniqueItems()
+
+
+### Example
+
+
+```typescript
+import {  } from '';
+import * as fs from 'fs';
+
+const configuration = .createConfiguration();
+const apiInstance = new .DefaultApi(configuration);
+
+let body:any = {};
+
+apiInstance.uniqueItems(body).then((data:any) => {
+  console.log('API called successfully. Returned data: ' + data);
+}).catch((error:any) => console.error(error));
+```
+
+
+### Parameters
+This endpoint does not need any parameter.
+
+
+### Return type
+
+**Response**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: Not defined
+ - **Accept**: application/json
+
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+**200** | OK |  -  |
+
+[[Back to top]](#) [[Back to API list]](README.md#documentation-for-api-endpoints) [[Back to Model list]](README.md#documentation-for-models) [[Back to README]](README.md)
+
+

samples/openapi3/client/petstore/typescript/builds/nullable-enum/README.md

@@ -0,0 +1,80 @@
+## @
+
+This generator creates TypeScript/JavaScript client that utilizes fetch-api.
+
+### Building
+
+To build and compile the typescript sources to javascript use:
+```
+npm install
+npm run build
+```
+
+### Publishing
+
+First build the package then run ```npm publish```
+
+### Consuming
+
+Navigate to the folder of your consuming project and run one of the following commands.
+
+_published:_
+
+```
+npm install @ --save
+```
+
+_unPublished (not recommended):_
+
+```
+npm install PATH_TO_GENERATED_PACKAGE --save
+```
+
+### Usage
+
+Below code snippet shows exemplary usage of the configuration and the API based 
+on the typical `PetStore` example used for OpenAPI. 
+
+```
+import * as your_api from 'your_api_package'
+
+// Covers all auth methods included in your OpenAPI yaml definition
+const authConfig: your_api.AuthMethodsConfiguration = {
+    "api_key": "YOUR_API_KEY"
+}
+
+// Implements a simple middleware to modify requests before (`pre`) they are sent
+// and after (`post`) they have been received 
+class Test implements your_api.Middleware {
+    pre(context: your_api.RequestContext): Promise<your_api.RequestContext> {
+        // Modify context here and return
+        return Promise.resolve(context);
+    }
+
+    post(context: your_api.ResponseContext): Promise<your_api.ResponseContext> {
+        return Promise.resolve(context);
+    }
+
+}
+
+// Create configuration parameter object
+const configurationParameters = {
+    httpApi: new your_api.JQueryHttpLibrary(), // Can also be ignored - default is usually fine
+    baseServer: your_api.servers[0], // First server is default
+    authMethods: authConfig, // No auth is default
+    promiseMiddleware: [new Test()],
+}
+
+// Convert to actual configuration
+const config = your_api.createConfiguration(configurationParameters);
+
+// Use configuration with your_api
+const api = new your_api.PetApi(config);
+your_api.Pet p = new your_api.Pet();
+p.name = "My new pet";
+p.photoUrls = [];
+p.tags = [];
+p.status = "available";
+Promise<your_api.Pet> createdPet = api.addPet(p);
+
+```

samples/openapi3/client/petstore/typescript/builds/nullable-enum/apis/DefaultApi.ts

@@ -0,0 +1,73 @@
+// TODO: better import syntax?
+import {BaseAPIRequestFactory, RequiredError, COLLECTION_FORMATS} from './baseapi';
+import {Configuration} from '../configuration';
+import {RequestContext, HttpMethod, ResponseContext, HttpFile, HttpInfo} from '../http/http';
+import {ObjectSerializer} from '../models/ObjectSerializer';
+import {ApiException} from './exception';
+import {canConsumeForm, isCodeInRange} from '../util';
+import {SecurityAuthentication} from '../auth/auth';
+
+
+import { Response } from '../models/Response';
+
+/**
+ * no description
+ */
+export class DefaultApiRequestFactory extends BaseAPIRequestFactory {
+
+    /**
+     */
+    public async uniqueItems(_options?: Configuration): Promise<RequestContext> {
+        let _config = _options || this.configuration;
+
+        // Path Params
+        const localVarPath = '/unique-items';
+
+        // Make Request Context
+        const requestContext = _config.baseServer.makeRequestContext(localVarPath, HttpMethod.GET);
+        requestContext.setHeaderParam("Accept", "application/json, */*;q=0.8")
+
+
+        
+        const defaultAuth: SecurityAuthentication | undefined = _options?.authMethods?.default || this.configuration?.authMethods?.default
+        if (defaultAuth?.applySecurityAuthentication) {
+            await defaultAuth?.applySecurityAuthentication(requestContext);
+        }
+
+        return requestContext;
+    }
+
+}
+
+export class DefaultApiResponseProcessor {
+
+    /**
+     * Unwraps the actual response sent by the server from the response context and deserializes the response content
+     * to the expected objects
+     *
+     * @params response Response returned by the server for a request to uniqueItems
+     * @throws ApiException if the response code was not in [200, 299]
+     */
+     public async uniqueItemsWithHttpInfo(response: ResponseContext): Promise<HttpInfo<Response >> {
+        const contentType = ObjectSerializer.normalizeMediaType(response.headers["content-type"]);
+        if (isCodeInRange("200", response.httpStatusCode)) {
+            const body: Response = ObjectSerializer.deserialize(
+                ObjectSerializer.parse(await response.body.text(), contentType),
+                "Response", ""
+            ) as Response;
+            return new HttpInfo(response.httpStatusCode, response.headers, response.body, body);
+        }
+
+        // Work around for missing responses in specification, e.g. for petstore.yaml
+        if (response.httpStatusCode >= 200 && response.httpStatusCode <= 299) {
+            const body: Response = ObjectSerializer.deserialize(
+                ObjectSerializer.parse(await response.body.text(), contentType),
+                "Response", ""
+            ) as Response;
+            return new HttpInfo(response.httpStatusCode, response.headers, response.body, body);
+        }
+
+        throw new ApiException<string | Blob | undefined>(response.httpStatusCode, "Unknown API Status Code!", await response.getBodyAsAny(), response.headers);
+    }
+
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/apis/baseapi.ts

@@ -0,0 +1,37 @@
+import { Configuration } from '../configuration'
+
+/**
+ *
+ * @export
+ */
+export const COLLECTION_FORMATS = {
+    csv: ",",
+    ssv: " ",
+    tsv: "\t",
+    pipes: "|",
+};
+
+
+/**
+ *
+ * @export
+ * @class BaseAPI
+ */
+export class BaseAPIRequestFactory {
+
+    constructor(protected configuration: Configuration) {
+    }
+};
+
+/**
+ *
+ * @export
+ * @class RequiredError
+ * @extends {Error}
+ */
+export class RequiredError extends Error {
+    name: "RequiredError" = "RequiredError";
+    constructor(public api: string, public method: string, public field: string) {
+        super("Required parameter " + field + " was null or undefined when calling " + api + "." + method + ".");
+    }
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/apis/exception.ts

@@ -0,0 +1,15 @@
+/**
+ * Represents an error caused by an api call i.e. it has attributes for a HTTP status code
+ * and the returned body object.
+ *
+ * Example
+ * API returns a ErrorMessageObject whenever HTTP status code is not in [200, 299]
+ * => ApiException(404, someErrorMessageObject)
+ *
+ */
+export class ApiException<T> extends Error {
+    public constructor(public code: number, message: string, public body: T, public headers: { [key: string]: string; }) {
+        super("HTTP-Code: " + code + "\nMessage: " + message + "\nBody: " + JSON.stringify(body) + "\nHeaders: " +
+        JSON.stringify(headers))
+    }
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/auth/auth.ts

@@ -0,0 +1,51 @@
+import { RequestContext } from "../http/http";
+
+/**
+ * Interface authentication schemes.
+ */
+export interface SecurityAuthentication {
+    /*
+     * @return returns the name of the security authentication as specified in OAI
+     */
+    getName(): string;
+
+    /**
+     * Applies the authentication scheme to the request context
+     *
+     * @params context the request context which should use this authentication scheme
+     */
+    applySecurityAuthentication(context: RequestContext): void | Promise<void>;
+}
+
+export interface TokenProvider {
+  getToken(): Promise<string> | string;
+}
+
+
+export type AuthMethods = {
+    "default"?: SecurityAuthentication,
+}
+
+export type ApiKeyConfiguration = string;
+export type HttpBasicConfiguration = { "username": string, "password": string };
+export type HttpBearerConfiguration = { tokenProvider: TokenProvider };
+export type OAuth2Configuration = { accessToken: string };
+
+export type AuthMethodsConfiguration = {
+    "default"?: SecurityAuthentication,
+}
+
+/**
+ * Creates the authentication methods from a swagger description.
+ *
+ */
+export function configureAuthMethods(config: AuthMethodsConfiguration | undefined): AuthMethods {
+    let authMethods: AuthMethods = {}
+
+    if (!config) {
+        return authMethods;
+    }
+    authMethods["default"] = config["default"]
+
+    return authMethods;
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/configuration.ts

@@ -0,0 +1,82 @@
+import { HttpLibrary } from "./http/http";
+import { Middleware, PromiseMiddleware, PromiseMiddlewareWrapper } from "./middleware";
+import { IsomorphicFetchHttpLibrary as DefaultHttpLibrary } from "./http/isomorphic-fetch";
+import { BaseServerConfiguration, server1 } from "./servers";
+import { configureAuthMethods, AuthMethods, AuthMethodsConfiguration } from "./auth/auth";
+
+export interface Configuration {
+    readonly baseServer: BaseServerConfiguration;
+    readonly httpApi: HttpLibrary;
+    readonly middleware: Middleware[];
+    readonly authMethods: AuthMethods;
+}
+
+
+/**
+ * Interface with which a configuration object can be configured.
+ */
+export interface ConfigurationParameters {
+    /**
+     * Default server to use - a list of available servers (according to the 
+     * OpenAPI yaml definition) is included in the `servers` const in `./servers`. You can also
+     * create your own server with the `ServerConfiguration` class from the same 
+     * file.
+     */
+    baseServer?: BaseServerConfiguration;
+    /**
+     * HTTP library to use e.g. IsomorphicFetch. This can usually be skipped as 
+     * all generators come with a default library.
+     * If available, additional libraries can be imported from `./http/*`
+     */
+    httpApi?: HttpLibrary;
+
+    /**
+     * The middlewares which will be applied to requests and responses. You can 
+     * add any number of middleware components to modify requests before they 
+     * are sent or before they are deserialized by implementing the `Middleware`
+     * interface defined in `./middleware`
+     */
+    middleware?: Middleware[];
+    /**
+     * Configures middleware functions that return promises instead of 
+     * Observables (which are used by `middleware`). Otherwise allows for the 
+     * same functionality as `middleware`, i.e., modifying requests before they 
+     * are sent and before they are deserialized.
+     */
+    promiseMiddleware?: PromiseMiddleware[];
+    /**
+     * Configuration for the available authentication methods (e.g., api keys) 
+     * according to the OpenAPI yaml definition. For the definition, please refer to 
+     * `./auth/auth`
+     */
+    authMethods?: AuthMethodsConfiguration
+}
+
+/**
+ * Provide your `ConfigurationParameters` to this function to get a `Configuration`
+ * object that can be used to configure your APIs (in the constructor or 
+ * for each request individually).
+ *
+ * If a property is not included in conf, a default is used:
+ *    - baseServer: server1
+ *    - httpApi: IsomorphicFetchHttpLibrary
+ *    - middleware: []
+ *    - promiseMiddleware: []
+ *    - authMethods: {}
+ *
+ * @param conf partial configuration
+ */
+export function createConfiguration(conf: ConfigurationParameters = {}): Configuration {
+    const configuration: Configuration = {
+        baseServer: conf.baseServer !== undefined ? conf.baseServer : server1,
+        httpApi: conf.httpApi || new DefaultHttpLibrary(),
+        middleware: conf.middleware || [],
+        authMethods: configureAuthMethods(conf.authMethods)
+    };
+    if (conf.promiseMiddleware) {
+        conf.promiseMiddleware.forEach(
+            m => configuration.middleware.push(new PromiseMiddlewareWrapper(m))
+        );
+    }
+    return configuration;
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/git_push.sh

@@ -0,0 +1,51 @@
+#!/bin/sh
+# ref: https://help.github.com/articles/adding-an-existing-project-to-github-using-the-command-line/
+#
+# Usage example: /bin/sh ./git_push.sh wing328 openapi-petstore-perl "minor update"
+
+git_user_id=$1
+git_repo_id=$2
+release_note=$3
+
+if [ "$git_user_id" = "" ]; then
+    git_user_id="GIT_USER_ID"
+    echo "[INFO] No command line input provided. Set \$git_user_id to $git_user_id"
+fi
+
+if [ "$git_repo_id" = "" ]; then
+    git_repo_id="GIT_REPO_ID"
+    echo "[INFO] No command line input provided. Set \$git_repo_id to $git_repo_id"
+fi
+
+if [ "$release_note" = "" ]; then
+    release_note="Minor update"
+    echo "[INFO] No command line input provided. Set \$release_note to $release_note"
+fi
+
+# Initialize the local directory as a Git repository
+git init
+
+# Adds the files in the local repository and stages them for commit.
+git add .
+
+# Commits the tracked changes and prepares them to be pushed to a remote repository.
+git commit -m "$release_note"
+
+# Sets the new remote
+git_remote=$(git remote)
+if [ "$git_remote" = "" ]; then # git remote not defined
+
+    if [ "$GIT_TOKEN" = "" ]; then
+        echo "[INFO] \$GIT_TOKEN (environment variable) is not set. Using the git credential in your environment."
+        git remote add origin https://github.com/${git_user_id}/${git_repo_id}.git
+    else
+        git remote add origin https://${git_user_id}:"${GIT_TOKEN}"@github.com/${git_user_id}/${git_repo_id}.git
+    fi
+
+fi
+
+git pull origin master
+
+# Pushes (Forces) the changes in the local repository up to the remote repository
+echo "Git pushing to https://github.com/${git_user_id}/${git_repo_id}.git"
+git push origin master 2>&1 | grep -v 'To https'

samples/openapi3/client/petstore/typescript/builds/nullable-enum/http/http.ts

@@ -0,0 +1,254 @@
+import { Observable, from } from '../rxjsStub';
+
+export * from './isomorphic-fetch';
+
+/**
+ * Represents an HTTP method.
+ */
+export enum HttpMethod {
+    GET = "GET",
+    HEAD = "HEAD",
+    POST = "POST",
+    PUT = "PUT",
+    DELETE = "DELETE",
+    CONNECT = "CONNECT",
+    OPTIONS = "OPTIONS",
+    TRACE = "TRACE",
+    PATCH = "PATCH"
+}
+
+/**
+ * Represents an HTTP file which will be transferred from or to a server.
+ */
+export type HttpFile = Blob & { readonly name: string };
+
+export class HttpException extends Error {
+    public constructor(msg: string) {
+        super(msg);
+    }
+}
+
+/**
+ * Represents the body of an outgoing HTTP request.
+ */
+export type RequestBody = undefined | string | FormData | URLSearchParams;
+
+function ensureAbsoluteUrl(url: string) {
+    if (url.startsWith("http://") || url.startsWith("https://")) {
+        return url;
+    }
+    return window.location.origin + url;
+}
+
+/**
+ * Represents an HTTP request context
+ */
+export class RequestContext {
+    private headers: { [key: string]: string } = {};
+    private body: RequestBody = undefined;
+    private url: URL;
+
+    /**
+     * Creates the request context using a http method and request resource url
+     *
+     * @param url url of the requested resource
+     * @param httpMethod http method
+     */
+    public constructor(url: string, private httpMethod: HttpMethod) {
+        this.url = new URL(ensureAbsoluteUrl(url));
+    }
+
+    /*
+     * Returns the url set in the constructor including the query string
+     *
+     */
+    public getUrl(): string {
+        return this.url.toString().endsWith("/") ?
+            this.url.toString().slice(0, -1)
+            : this.url.toString();
+    }
+
+    /**
+     * Replaces the url set in the constructor with this url.
+     *
+     */
+    public setUrl(url: string) {
+        this.url = new URL(ensureAbsoluteUrl(url));
+    }
+
+    /**
+     * Sets the body of the http request either as a string or FormData
+     *
+     * Note that setting a body on a HTTP GET, HEAD, DELETE, CONNECT or TRACE
+     * request is discouraged.
+     * https://httpwg.org/http-core/draft-ietf-httpbis-semantics-latest.html#rfc.section.7.3.1
+     *
+     * @param body the body of the request
+     */
+    public setBody(body: RequestBody) {
+        this.body = body;
+    }
+
+    public getHttpMethod(): HttpMethod {
+        return this.httpMethod;
+    }
+
+    public getHeaders(): { [key: string]: string } {
+        return this.headers;
+    }
+
+    public getBody(): RequestBody {
+        return this.body;
+    }
+
+    public setQueryParam(name: string, value: string) {
+        this.url.searchParams.set(name, value);
+    }
+
+    public appendQueryParam(name: string, value: string) {
+        this.url.searchParams.append(name, value);
+    }
+
+    /**
+     * Sets a cookie with the name and value. NO check  for duplicate cookies is performed
+     *
+     */
+    public addCookie(name: string, value: string): void {
+        if (!this.headers["Cookie"]) {
+            this.headers["Cookie"] = "";
+        }
+        this.headers["Cookie"] += name + "=" + value + "; ";
+    }
+
+    public setHeaderParam(key: string, value: string): void  {
+        this.headers[key] = value;
+    }
+}
+
+export interface ResponseBody {
+    text(): Promise<string>;
+    binary(): Promise<Blob>;
+}
+
+/**
+ * Helper class to generate a `ResponseBody` from binary data
+ */
+export class SelfDecodingBody implements ResponseBody {
+    constructor(private dataSource: Promise<Blob>) {}
+
+    binary(): Promise<Blob> {
+        return this.dataSource;
+    }
+
+    async text(): Promise<string> {
+        const data: Blob = await this.dataSource;
+        // @ts-ignore
+        if (data.text) {
+            // @ts-ignore
+            return data.text();
+        }
+
+        return new Promise<string>((resolve, reject) => {
+            const reader = new FileReader();
+            reader.addEventListener("load", () => resolve(reader.result as string));
+            reader.addEventListener("error", () => reject(reader.error));
+            reader.readAsText(data);
+        });
+    }
+}
+
+export class ResponseContext {
+    public constructor(
+        public httpStatusCode: number,
+        public headers: { [key: string]: string },
+        public body: ResponseBody
+    ) {}
+
+    /**
+     * Parse header value in the form `value; param1="value1"`
+     *
+     * E.g. for Content-Type or Content-Disposition
+     * Parameter names are converted to lower case
+     * The first parameter is returned with the key `""`
+     */
+    public getParsedHeader(headerName: string): { [parameter: string]: string } {
+        const result: { [parameter: string]: string } = {};
+        if (!this.headers[headerName]) {
+            return result;
+        }
+
+        const parameters = this.headers[headerName].split(";");
+        for (const parameter of parameters) {
+            let [key, value] = parameter.split("=", 2);
+            key = key.toLowerCase().trim();
+            if (value === undefined) {
+                result[""] = key;
+            } else {
+                value = value.trim();
+                if (value.startsWith('"') && value.endsWith('"')) {
+                    value = value.substring(1, value.length - 1);
+                }
+                result[key] = value;
+            }
+        }
+        return result;
+    }
+
+    public async getBodyAsFile(): Promise<HttpFile> {
+        const data = await this.body.binary();
+        const fileName = this.getParsedHeader("content-disposition")["filename"] || "";
+        const contentType = this.headers["content-type"] || "";
+        try {
+            return new File([data], fileName, { type: contentType });
+        } catch (error) {
+            /** Fallback for when the File constructor is not available */
+            return Object.assign(data, {
+                name: fileName,
+                type: contentType
+            });
+        }
+    }
+
+    /**
+     * Use a heuristic to get a body of unknown data structure.
+     * Return as string if possible, otherwise as binary.
+     */
+    public getBodyAsAny(): Promise<string | Blob | undefined> {
+        try {
+            return this.body.text();
+        } catch {}
+
+        try {
+            return this.body.binary();
+        } catch {}
+
+        return Promise.resolve(undefined);
+    }
+}
+
+export interface HttpLibrary {
+    send(request: RequestContext): Observable<ResponseContext>;
+}
+
+export interface PromiseHttpLibrary {
+    send(request: RequestContext): Promise<ResponseContext>;
+}
+
+export function wrapHttpLibrary(promiseHttpLibrary: PromiseHttpLibrary): HttpLibrary {
+  return {
+    send(request: RequestContext): Observable<ResponseContext> {
+      return from(promiseHttpLibrary.send(request));
+    }
+  }
+}
+
+export class HttpInfo<T> extends ResponseContext {
+    public constructor(
+        public httpStatusCode: number,
+        public headers: { [key: string]: string },
+        public body: ResponseBody,
+        public data: T,
+    ) {
+        super(httpStatusCode, headers, body);
+    }
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/http/isomorphic-fetch.ts

@@ -0,0 +1,32 @@
+import {HttpLibrary, RequestContext, ResponseContext} from './http';
+import { from, Observable } from '../rxjsStub';
+import "whatwg-fetch";
+
+export class IsomorphicFetchHttpLibrary implements HttpLibrary {
+
+    public send(request: RequestContext): Observable<ResponseContext> {
+        let method = request.getHttpMethod().toString();
+        let body = request.getBody();
+
+        const resultPromise = fetch(request.getUrl(), {
+            method: method,
+            body: body as any,
+            headers: request.getHeaders(),
+            credentials: "same-origin"
+        }).then((resp: any) => {
+            const headers: { [name: string]: string } = {};
+            resp.headers.forEach((value: string, name: string) => {
+              headers[name] = value;
+            });
+
+            const body = {
+              text: () => resp.text(),
+              binary: () => resp.blob()
+            };
+            return new ResponseContext(resp.status, headers, body);
+        });
+
+        return from<Promise<ResponseContext>>(resultPromise);
+
+    }
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/index.ts

@@ -0,0 +1,12 @@
+export * from "./http/http";
+export * from "./auth/auth";
+export * from "./models/all";
+export { createConfiguration } from "./configuration"
+export { Configuration } from "./configuration"
+export * from "./apis/exception";
+export * from "./servers";
+export { RequiredError } from "./apis/baseapi";
+
+export { PromiseMiddleware as Middleware } from './middleware';
+export { PromiseDefaultApi as DefaultApi } from './types/PromiseAPI';
+

samples/openapi3/client/petstore/typescript/builds/nullable-enum/middleware.ts

@@ -0,0 +1,66 @@
+import {RequestContext, ResponseContext} from './http/http';
+import { Observable, from } from './rxjsStub';
+
+/**
+ * Defines the contract for a middleware intercepting requests before
+ * they are sent (but after the RequestContext was created)
+ * and before the ResponseContext is unwrapped.
+ *
+ */
+export interface Middleware {
+    /**
+     * Modifies the request before the request is sent.
+     *
+     * @param context RequestContext of a request which is about to be sent to the server
+     * @returns an observable of the updated request context
+     *
+     */
+    pre(context: RequestContext): Observable<RequestContext>;
+    /**
+     * Modifies the returned response before it is deserialized.
+     *
+     * @param context ResponseContext of a sent request
+     * @returns an observable of the modified response context
+     */
+    post(context: ResponseContext): Observable<ResponseContext>;
+}
+
+export class PromiseMiddlewareWrapper implements Middleware {
+
+    public constructor(private middleware: PromiseMiddleware) {
+
+    }
+
+    pre(context: RequestContext): Observable<RequestContext> {
+        return from(this.middleware.pre(context));
+    }
+
+    post(context: ResponseContext): Observable<ResponseContext> {
+        return from(this.middleware.post(context));
+    }
+
+}
+
+/**
+ * Defines the contract for a middleware intercepting requests before
+ * they are sent (but after the RequestContext was created)
+ * and before the ResponseContext is unwrapped.
+ *
+ */
+export interface PromiseMiddleware {
+    /**
+     * Modifies the request before the request is sent.
+     *
+     * @param context RequestContext of a request which is about to be sent to the server
+     * @returns an observable of the updated request context
+     *
+     */
+    pre(context: RequestContext): Promise<RequestContext>;
+        /**
+     * Modifies the returned response before it is deserialized.
+     *
+     * @param context ResponseContext of a sent request
+     * @returns an observable of the modified response context
+     */
+    post(context: ResponseContext): Promise<ResponseContext>;
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/models/ObjectSerializer.ts

@@ -0,0 +1,270 @@
+export * from '../models/Response';
+
+import { Response, ResponseEnrichmentSourceEnum   } from '../models/Response';
+
+/* tslint:disable:no-unused-variable */
+let primitives = [
+                    "string",
+                    "boolean",
+                    "double",
+                    "integer",
+                    "long",
+                    "float",
+                    "number",
+                    "any"
+                 ];
+
+let enumsMap: Set<string> = new Set<string>([
+    "ResponseEnrichmentSourceEnum",
+]);
+
+let typeMap: {[index: string]: any} = {
+    "Response": Response,
+}
+
+type MimeTypeDescriptor = {
+    type: string;
+    subtype: string;
+    subtypeTokens: string[];
+};
+
+/**
+ * Every mime-type consists of a type, subtype, and optional parameters.
+ * The subtype can be composite, including information about the content format.
+ * For example: `application/json-patch+json`, `application/merge-patch+json`.
+ *
+ * This helper transforms a string mime-type into an internal representation.
+ * This simplifies the implementation of predicates that in turn define common rules for parsing or stringifying
+ * the payload.
+ */
+const parseMimeType = (mimeType: string): MimeTypeDescriptor => {
+    const [type, subtype] = mimeType.split('/');
+    return {
+        type,
+        subtype,
+        subtypeTokens: subtype.split('+'),
+    };
+};
+
+type MimeTypePredicate = (mimeType: string) => boolean;
+
+// This factory creates a predicate function that checks a string mime-type against defined rules.
+const mimeTypePredicateFactory = (predicate: (descriptor: MimeTypeDescriptor) => boolean): MimeTypePredicate => (mimeType) => predicate(parseMimeType(mimeType));
+
+// Use this factory when you need to define a simple predicate based only on type and, if applicable, subtype.
+const mimeTypeSimplePredicateFactory = (type: string, subtype?: string): MimeTypePredicate => mimeTypePredicateFactory((descriptor) => {
+    if (descriptor.type !== type) return false;
+    if (subtype != null && descriptor.subtype !== subtype) return false;
+    return true;
+});
+
+// Creating a set of named predicates that will help us determine how to handle different mime-types
+const isTextLikeMimeType = mimeTypeSimplePredicateFactory('text');
+const isJsonMimeType = mimeTypeSimplePredicateFactory('application', 'json');
+const isJsonLikeMimeType = mimeTypePredicateFactory((descriptor) => descriptor.type === 'application' && descriptor.subtypeTokens.some((item) => item === 'json'));
+const isOctetStreamMimeType = mimeTypeSimplePredicateFactory('application', 'octet-stream');
+const isFormUrlencodedMimeType = mimeTypeSimplePredicateFactory('application', 'x-www-form-urlencoded');
+
+// Defining a list of mime-types in the order of prioritization for handling.
+const supportedMimeTypePredicatesWithPriority: MimeTypePredicate[] = [
+    isJsonMimeType,
+    isJsonLikeMimeType,
+    isTextLikeMimeType,
+    isOctetStreamMimeType,
+    isFormUrlencodedMimeType,
+];
+
+export class ObjectSerializer {
+    public static findCorrectType(data: any, expectedType: string) {
+        if (data == undefined) {
+            return expectedType;
+        } else if (primitives.indexOf(expectedType.toLowerCase()) !== -1) {
+            return expectedType;
+        } else if (expectedType === "Date") {
+            return expectedType;
+        } else {
+            if (enumsMap.has(expectedType)) {
+                return expectedType;
+            }
+
+            if (!typeMap[expectedType]) {
+                return expectedType; // w/e we don't know the type
+            }
+
+            // Check the discriminator
+            let discriminatorProperty = typeMap[expectedType].discriminator;
+            if (discriminatorProperty == null) {
+                return expectedType; // the type does not have a discriminator. use it.
+            } else {
+                if (data[discriminatorProperty]) {
+                    var discriminatorType = data[discriminatorProperty];
+                    let mapping = typeMap[expectedType].mapping;
+                    if (mapping != undefined && mapping[discriminatorType]) {
+                        return mapping[discriminatorType]; // use the type given in the discriminator
+                    } else if(typeMap[discriminatorType]) {
+                        return discriminatorType;
+                    } else {
+                        return expectedType; // discriminator did not map to a type
+                    }
+                } else {
+                    return expectedType; // discriminator was not present (or an empty string)
+                }
+            }
+        }
+    }
+
+    public static serialize(data: any, type: string, format: string) {
+        if (data == undefined) {
+            return data;
+        } else if (primitives.indexOf(type.toLowerCase()) !== -1) {
+            return data;
+        } else if (type.lastIndexOf("Array<", 0) === 0) { // string.startsWith pre es6
+            let subType: string = type.replace("Array<", ""); // Array<Type> => Type>
+            subType = subType.substring(0, subType.length - 1); // Type> => Type
+            let transformedData: any[] = [];
+            for (let date of data) {
+                transformedData.push(ObjectSerializer.serialize(date, subType, format));
+            }
+            return transformedData;
+        } else if (type === "Date") {
+            if (format == "date") {
+                let month = data.getMonth()+1
+                month = month < 10 ? "0" + month.toString() : month.toString()
+                let day = data.getDate();
+                day = day < 10 ? "0" + day.toString() : day.toString();
+
+                return data.getFullYear() + "-" + month + "-" + day;
+            } else {
+                return data.toISOString();
+            }
+        } else {
+            if (enumsMap.has(type)) {
+                return data;
+            }
+            if (!typeMap[type]) { // in case we dont know the type
+                return data;
+            }
+
+            // Get the actual type of this object
+            type = this.findCorrectType(data, type);
+
+            // get the map for the correct type.
+            let attributeTypes = typeMap[type].getAttributeTypeMap();
+            let instance: {[index: string]: any} = {};
+            for (let attributeType of attributeTypes) {
+                instance[attributeType.baseName] = ObjectSerializer.serialize(data[attributeType.name], attributeType.type, attributeType.format);
+            }
+            return instance;
+        }
+    }
+
+    public static deserialize(data: any, type: string, format: string) {
+        // polymorphism may change the actual type.
+        type = ObjectSerializer.findCorrectType(data, type);
+        if (data == undefined) {
+            return data;
+        } else if (primitives.indexOf(type.toLowerCase()) !== -1) {
+            return data;
+        } else if (type.lastIndexOf("Array<", 0) === 0) { // string.startsWith pre es6
+            let subType: string = type.replace("Array<", ""); // Array<Type> => Type>
+            subType = subType.substring(0, subType.length - 1); // Type> => Type
+            let transformedData: any[] = [];
+            for (let date of data) {
+                transformedData.push(ObjectSerializer.deserialize(date, subType, format));
+            }
+            return transformedData;
+        } else if (type === "Date") {
+            return new Date(data);
+        } else {
+            if (enumsMap.has(type)) {// is Enum
+                return data;
+            }
+
+            if (!typeMap[type]) { // dont know the type
+                return data;
+            }
+            let instance = new typeMap[type]();
+            let attributeTypes = typeMap[type].getAttributeTypeMap();
+            for (let attributeType of attributeTypes) {
+                let value = ObjectSerializer.deserialize(data[attributeType.baseName], attributeType.type, attributeType.format);
+                if (value !== undefined) {
+                    instance[attributeType.name] = value;
+                }
+            }
+            return instance;
+        }
+    }
+
+
+    /**
+     * Normalize media type
+     *
+     * We currently do not handle any media types attributes, i.e. anything
+     * after a semicolon. All content is assumed to be UTF-8 compatible.
+     */
+    public static normalizeMediaType(mediaType: string | undefined): string | undefined {
+        if (mediaType === undefined) {
+            return undefined;
+        }
+        return mediaType.split(";")[0].trim().toLowerCase();
+    }
+
+    /**
+     * From a list of possible media types, choose the one we can handle best.
+     *
+     * The order of the given media types does not have any impact on the choice
+     * made.
+     */
+    public static getPreferredMediaType(mediaTypes: Array<string>): string {
+        /** According to OAS 3 we should default to json */
+        if (mediaTypes.length === 0) {
+            return "application/json";
+        }
+
+        const normalMediaTypes = mediaTypes.map(this.normalizeMediaType);
+
+        for (const predicate of supportedMimeTypePredicatesWithPriority) {
+            for (const mediaType of normalMediaTypes) {
+                if (mediaType != null && predicate(mediaType)) {
+                    return mediaType;
+                }
+            }
+        }
+
+        throw new Error("None of the given media types are supported: " + mediaTypes.join(", "));
+    }
+
+    /**
+     * Convert data to a string according the given media type
+     */
+    public static stringify(data: any, mediaType: string): string {
+        if (isTextLikeMimeType(mediaType)) {
+            return String(data);
+        }
+
+        if (isJsonLikeMimeType(mediaType)) {
+            return JSON.stringify(data);
+        }
+
+        throw new Error("The mediaType " + mediaType + " is not supported by ObjectSerializer.stringify.");
+    }
+
+    /**
+     * Parse data from a string according to the given media type
+     */
+    public static parse(rawData: string, mediaType: string | undefined) {
+        if (mediaType === undefined) {
+            throw new Error("Cannot parse content. No Content-Type defined.");
+        }
+
+        if (isTextLikeMimeType(mediaType)) {
+            return rawData;
+        }
+
+        if (isJsonLikeMimeType(mediaType)) {
+            return JSON.parse(rawData);
+        }
+
+        throw new Error("The mediaType " + mediaType + " is not supported by ObjectSerializer.parse.");
+    }
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/models/Response.ts

@@ -0,0 +1,45 @@
+/**
+ * Sample for uniqueItems
+ * No description provided (generated by Openapi Generator https://github.com/openapitools/openapi-generator)
+ *
+ * OpenAPI spec version: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+import { HttpFile } from '../http/http';
+
+export class Response {
+    /**
+    * The source of the data in this Field (if it is enriched)
+    */
+    'enrichmentSource'?: ResponseEnrichmentSourceEnum | null;
+
+    static readonly discriminator: string | undefined = undefined;
+
+    static readonly mapping: {[index: string]: string} | undefined = undefined;
+
+    static readonly attributeTypeMap: Array<{name: string, baseName: string, type: string, format: string}> = [
+        {
+            "name": "enrichmentSource",
+            "baseName": "enrichmentSource",
+            "type": "ResponseEnrichmentSourceEnum",
+            "format": ""
+        }    ];
+
+    static getAttributeTypeMap() {
+        return Response.attributeTypeMap;
+    }
+
+    public constructor() {
+    }
+}
+
+export enum ResponseEnrichmentSourceEnum {
+    AffinityData = 'affinity-data',
+    Dealroom = 'dealroom'
+}
+

samples/openapi3/client/petstore/typescript/builds/nullable-enum/models/all.ts

@@ -0,0 +1 @@
+export * from '../models/Response'

samples/openapi3/client/petstore/typescript/builds/nullable-enum/package.json

@@ -0,0 +1,42 @@
+{
+  "name": "",
+  "version": "",
+  "description": "OpenAPI client for ",
+  "author": "OpenAPI-Generator Contributors",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/GIT_USER_ID/GIT_REPO_ID.git"
+  },
+  "keywords": [
+    "fetch",
+    "typescript",
+    "openapi-client",
+    "openapi-generator"
+  ],
+  "license": "Unlicense",
+  "main": "./dist/index.js",
+  "type": "commonjs",
+  "exports": {
+    ".": {
+      "require": "./dist/index.js",
+      "types": "./dist/index.d.js"
+    }
+  },
+  "files": [
+    "dist"
+  ],
+  "typings": "./dist/index.d.ts",
+  "scripts": {
+    "build": "tsc",
+    "prepare": "npm run build"
+  },
+  "dependencies": {
+    "whatwg-fetch": "^3.0.0",
+    "es6-promise": "^4.2.4",
+    "url-parse": "^1.4.3"
+  },
+  "devDependencies": {
+    "typescript": "^4.0",
+    "@types/url-parse": "1.4.4"
+  }
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/rxjsStub.ts

@@ -0,0 +1,27 @@
+export class Observable<T> {
+  constructor(private promise: Promise<T>) {}
+
+  toPromise() {
+    return this.promise;
+  }
+
+  pipe<S>(callback: (value: T) => S | Promise<S>): Observable<S> {
+    return new Observable(this.promise.then(callback));
+  }
+}
+
+export function from<T>(promise: Promise<any>) {
+  return new Observable(promise);
+}
+
+export function of<T>(value: T) {
+  return new Observable<T>(Promise.resolve(value));
+}
+
+export function mergeMap<T, S>(callback: (value: T) => Observable<S>) {
+  return (value: T) => callback(value).toPromise();
+}
+
+export function map(callback: any) {
+  return callback;
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/servers.ts

@@ -0,0 +1,55 @@
+import { RequestContext, HttpMethod } from "./http/http";
+
+export interface BaseServerConfiguration {
+    makeRequestContext(endpoint: string, httpMethod: HttpMethod): RequestContext;
+}
+
+/**
+ *
+ * Represents the configuration of a server including its
+ * url template and variable configuration based on the url.
+ *
+ */
+export class ServerConfiguration<T extends { [key: string]: string }> implements BaseServerConfiguration {
+    public constructor(private url: string, private variableConfiguration: T) {}
+
+    /**
+     * Sets the value of the variables of this server. Variables are included in 
+     * the `url` of this ServerConfiguration in the form `{variableName}`
+     *
+     * @param variableConfiguration a partial variable configuration for the 
+     * variables contained in the url
+     */
+    public setVariables(variableConfiguration: Partial<T>) {
+        Object.assign(this.variableConfiguration, variableConfiguration);
+    }
+
+    public getConfiguration(): T {
+        return this.variableConfiguration
+    }
+
+    private getUrl() {
+        let replacedUrl = this.url;
+        for (const key in this.variableConfiguration) {
+            var re = new RegExp("{" + key + "}","g");
+            replacedUrl = replacedUrl.replace(re, this.variableConfiguration[key]);
+        }
+        return replacedUrl
+    }
+
+    /**
+     * Creates a new request context for this server using the url with variables
+     * replaced with their respective values and the endpoint of the request appended.
+     *
+     * @param endpoint the endpoint to be queried on the server
+     * @param httpMethod httpMethod to be used
+     *
+     */
+    public makeRequestContext(endpoint: string, httpMethod: HttpMethod): RequestContext {
+        return new RequestContext(this.getUrl() + endpoint, httpMethod);
+    }
+}
+
+export const server1 = new ServerConfiguration<{  }>("http://localhost:3000", {  })
+
+export const servers = [server1];

samples/openapi3/client/petstore/typescript/builds/nullable-enum/tsconfig.json

@@ -0,0 +1,28 @@
+{
+  "compilerOptions": {
+    "strict": true,
+    /* Basic Options */
+    "target": "es5",
+    "moduleResolution": "node",
+    "declaration": true,
+
+    /* Additional Checks */
+     "noUnusedLocals": false,                /* Report errors on unused locals. */ // TODO: reenable (unused imports!)
+     "noUnusedParameters": false,            /* Report errors on unused parameters. */ // TODO: set to true again
+     "noImplicitReturns": true,             /* Report error when not all code paths in function return a value. */
+     "noFallthroughCasesInSwitch": true,    /* Report errors for fallthrough cases in switch statement. */
+
+    "removeComments": true,
+    "sourceMap": true,
+    "outDir": "./dist",
+    "noLib": false,
+    "lib": [ "es6", "dom" ],
+  },
+  "exclude": [
+    "dist",
+    "node_modules"
+  ],
+  "filesGlob": [
+    "./**/*.ts",
+  ]
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/types/ObjectParamAPI.ts

@@ -0,0 +1,33 @@
+import { ResponseContext, RequestContext, HttpFile, HttpInfo } from '../http/http';
+import { Configuration} from '../configuration'
+
+import { Response } from '../models/Response';
+
+import { ObservableDefaultApi } from "./ObservableAPI";
+import { DefaultApiRequestFactory, DefaultApiResponseProcessor} from "../apis/DefaultApi";
+
+export interface DefaultApiUniqueItemsRequest {
+}
+
+export class ObjectDefaultApi {
+    private api: ObservableDefaultApi
+
+    public constructor(configuration: Configuration, requestFactory?: DefaultApiRequestFactory, responseProcessor?: DefaultApiResponseProcessor) {
+        this.api = new ObservableDefaultApi(configuration, requestFactory, responseProcessor);
+    }
+
+    /**
+     * @param param the request object
+     */
+    public uniqueItemsWithHttpInfo(param: DefaultApiUniqueItemsRequest = {}, options?: Configuration): Promise<HttpInfo<Response>> {
+        return this.api.uniqueItemsWithHttpInfo( options).toPromise();
+    }
+
+    /**
+     * @param param the request object
+     */
+    public uniqueItems(param: DefaultApiUniqueItemsRequest = {}, options?: Configuration): Promise<Response> {
+        return this.api.uniqueItems( options).toPromise();
+    }
+
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/types/ObservableAPI.ts

@@ -0,0 +1,50 @@
+import { ResponseContext, RequestContext, HttpFile, HttpInfo } from '../http/http';
+import { Configuration} from '../configuration'
+import { Observable, of, from } from '../rxjsStub';
+import {mergeMap, map} from  '../rxjsStub';
+import { Response } from '../models/Response';
+
+import { DefaultApiRequestFactory, DefaultApiResponseProcessor} from "../apis/DefaultApi";
+export class ObservableDefaultApi {
+    private requestFactory: DefaultApiRequestFactory;
+    private responseProcessor: DefaultApiResponseProcessor;
+    private configuration: Configuration;
+
+    public constructor(
+        configuration: Configuration,
+        requestFactory?: DefaultApiRequestFactory,
+        responseProcessor?: DefaultApiResponseProcessor
+    ) {
+        this.configuration = configuration;
+        this.requestFactory = requestFactory || new DefaultApiRequestFactory(configuration);
+        this.responseProcessor = responseProcessor || new DefaultApiResponseProcessor();
+    }
+
+    /**
+     */
+    public uniqueItemsWithHttpInfo(_options?: Configuration): Observable<HttpInfo<Response>> {
+        const requestContextPromise = this.requestFactory.uniqueItems(_options);
+
+        // build promise chain
+        let middlewarePreObservable = from<RequestContext>(requestContextPromise);
+        for (const middleware of this.configuration.middleware) {
+            middlewarePreObservable = middlewarePreObservable.pipe(mergeMap((ctx: RequestContext) => middleware.pre(ctx)));
+        }
+
+        return middlewarePreObservable.pipe(mergeMap((ctx: RequestContext) => this.configuration.httpApi.send(ctx))).
+            pipe(mergeMap((response: ResponseContext) => {
+                let middlewarePostObservable = of(response);
+                for (const middleware of this.configuration.middleware) {
+                    middlewarePostObservable = middlewarePostObservable.pipe(mergeMap((rsp: ResponseContext) => middleware.post(rsp)));
+                }
+                return middlewarePostObservable.pipe(map((rsp: ResponseContext) => this.responseProcessor.uniqueItemsWithHttpInfo(rsp)));
+            }));
+    }
+
+    /**
+     */
+    public uniqueItems(_options?: Configuration): Observable<Response> {
+        return this.uniqueItemsWithHttpInfo(_options).pipe(map((apiResponse: HttpInfo<Response>) => apiResponse.data));
+    }
+
+}

samples/openapi3/client/petstore/typescript/builds/nullable-enum/types/PromiseAPI.ts

@@ -0,0 +1,37 @@
+import { ResponseContext, RequestContext, HttpFile, HttpInfo } from '../http/http';
+import { Configuration} from '../configuration'
+
+import { Response } from '../models/Response';
+import { ObservableDefaultApi } from './ObservableAPI';
+
+import { DefaultApiRequestFactory, DefaultApiResponseProcessor} from "../apis/DefaultApi";
+export class PromiseDefaultApi {
+    private api: ObservableDefaultApi
+
+    public constructor(
+        configuration: Configuration,
+        requestFactory?: DefaultApiRequestFactory,
+        responseProcessor?: DefaultApiResponseProcessor
+    ) {
+        this.api = new ObservableDefaultApi(configuration, requestFactory, responseProcessor);
+    }
+
+    /**
+     */
+    public uniqueItemsWithHttpInfo(_options?: Configuration): Promise<HttpInfo<Response>> {
+        const result = this.api.uniqueItemsWithHttpInfo(_options);
+        return result.toPromise();
+    }
+
+    /**
+     */
+    public uniqueItems(_options?: Configuration): Promise<Response> {
+        const result = this.api.uniqueItems(_options);
+        return result.toPromise();
+    }
+
+
+}
+
+
+

samples/openapi3/client/petstore/typescript/builds/nullable-enum/util.ts

@@ -0,0 +1,37 @@
+/**
+ * Returns if a specific http code is in a given code range
+ * where the code range is defined as a combination of digits
+ * and "X" (the letter X) with a length of 3
+ *
+ * @param codeRange string with length 3 consisting of digits and "X" (the letter X)
+ * @param code the http status code to be checked against the code range
+ */
+export function isCodeInRange(codeRange: string, code: number): boolean {
+    // This is how the default value is encoded in OAG
+    if (codeRange === "0") {
+        return true;
+    }
+    if (codeRange == code.toString()) {
+        return true;
+    } else {
+        const codeString = code.toString();
+        if (codeString.length != codeRange.length) {
+            return false;
+        }
+        for (let i = 0; i < codeString.length; i++) {
+            if (codeRange.charAt(i) != "X" && codeRange.charAt(i) != codeString.charAt(i)) {
+                return false;
+            }
+        }
+        return true;
+    }
+}
+
+/**
+* Returns if it can consume form
+*
+* @param consumes array
+*/
+export function canConsumeForm(contentTypes: string[]): boolean {
+    return contentTypes.indexOf('multipart/form-data') !== -1
+}