Create OneOfInterface for OneOfModels

Author: ksvirkou-hubspot

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

@@ -174,6 +174,7 @@ public TypeScriptClientCodegen() {
         // models
         setModelPackage("models");
         supportingFiles.add(new SupportingFile("model" + File.separator + "ObjectSerializer.mustache", "models", "ObjectSerializer.ts"));
+        supportingFiles.add(new SupportingFile("model" + File.separator + "OneOfInterface.mustache", "models", "OneOfInterface.ts"));
         modelTemplateFiles.put("model" + File.separator + "model.mustache", ".ts");
 
         // api

modules/openapi-generator/src/main/resources/typescript/model/OneOfInterface.mustache

@@ -0,0 +1,3 @@
+export interface OneOfInterface {
+    findMatchingType(): string | undefined;
+}

modules/openapi-generator/src/main/resources/typescript/model/model.mustache

@@ -4,7 +4,14 @@
 {{#tsImports}}
 import { {{classname}} } from '{{filename}}{{importFileExtension}}';
 {{/tsImports}}
+{{#oneOf}}
+    {{#-first}}
+import { OneOfInterface } from '../models/OneOfInterface{{importFileExtension}}'
+    {{/-first}}
+{{/oneOf}}
+{{^oneOf}}
 import { HttpFile } from '../http/http{{importFileExtension}}';
+{{/oneOf}}
 
 {{#description}}
 /**

modules/openapi-generator/src/main/resources/typescript/model/modelOneOf.mustache

@@ -1,11 +1,3 @@
-{{#hasImports}}
-import {
-    {{#imports}}
-    {{{.}}}{{importFileExtension}},
-    {{/imports}}
-} from './';
-
-{{/hasImports}}
 /**
  * @type {{classname}}
  * Type
@@ -18,7 +10,7 @@ export type {{classname}} = {{#oneOf}}{{{.}}}{{^-last}} | {{/-last}}{{/oneOf}};
     * {{{.}}}{{/description}}
 * @export
 */
-export class {{classname}}Class {
+export class {{classname}}Class implements OneOfInterface {
     {{#discriminator}}
     static readonly discriminator: string | undefined = "{{discriminatorName}}";
     {{/discriminator}}
@@ -37,4 +29,8 @@ export class {{classname}}Class {
 
     static readonly mapping: {[index: string]: string} | undefined = undefined;
     {{/hasDiscriminatorWithNonEmptyMapping}}
+
+    findMatchingType(): string | undefined {
+        return undefined;
+    }
 }