handle calls while running requests

* add map to hold subjects to cancel requests,
if a request is still running and a new call is done

Author: malaupa

src/mustache/api.service.mustache

@@ -20,13 +20,15 @@ import { CustomQueryEncoderHelper }                          from '../encoder';
 
 {{^useRxJS6}}
 import { Observable }                                        from 'rxjs/Observable';
+import { Subject }                                           from 'rxjs/Subject';
 {{/useRxJS6}}
 {{#useRxJS6}}
-import { Observable }                                        from 'rxjs';
+import { Observable, Subject }                               from 'rxjs';
 import { catchError }                                        from 'rxjs/operators';
 {{/useRxJS6}}
 {{^useHttpClient}}
 import '../rxjs-operators';
+import 'rxjs/add/operator/takeUntil';
 {{/useHttpClient}}
 
 {{#imports}}
@@ -65,6 +67,7 @@ export class {{classname}} {
     protected basePath = '{{{basePath}}}';
     public defaultHeaders = new {{#useHttpClient}}Http{{/useHttpClient}}Headers();
     public configuration = new Configuration();
+    private cancelMap: {[key: string]: Subject<any>};
 
     constructor(protected {{#useHttpClient}}httpClient: HttpClient{{/useHttpClient}}{{^useHttpClient}}http: Http{{/useHttpClient}}, @Optional()@Inject(BASE_PATH) basePath: string, @Optional() configuration: Configuration) {
 
@@ -315,7 +318,7 @@ export class {{classname}} {
 
 {{/hasFormParams}}
 {{#useHttpClient}}
-        const handle = this.httpClient.{{httpMethod}}{{^isResponseFile}}<{{#returnType}}{{{returnType}}}{{#isResponseTypeFile}}|undefined{{/isResponseTypeFile}}{{/returnType}}{{^returnType}}any{{/returnType}}>{{/isResponseFile}}(`${this.configuration.basePath}{{{path}}}`,{{#isBodyAllowed}}
+        let handle = this.httpClient.{{httpMethod}}{{^isResponseFile}}<{{#returnType}}{{{returnType}}}{{#isResponseTypeFile}}|undefined{{/isResponseTypeFile}}{{/returnType}}{{^returnType}}any{{/returnType}}>{{/isResponseFile}}(`${this.configuration.basePath}{{{path}}}`,{{#isBodyAllowed}}
             {{#bodyParam}}{{paramName}}{{/bodyParam}}{{^bodyParam}}{{#hasFormParams}}convertFormParamsToString ? formParams.toString() : formParams{{/hasFormParams}}{{^hasFormParams}}null{{/hasFormParams}}{{/bodyParam}},{{/isBodyAllowed}}
             {
 {{#hasQueryParams}}
@@ -330,6 +333,15 @@ export class {{classname}} {
                 reportProgress: reportProgress
             }
         );
+        if (this.cancelMap['{{operationIdOriginal}}']) {
+            this.cancelMap['{{operationIdOriginal}}'].next();
+            this.cancelMap['{{operationIdOriginal}}'].complete();
+            this.cancelMap['{{operationIdOriginal}}'] = null;
+        }
+        this.cancelMap['{{operationIdOriginal}}'] = {{httpMethod}} === 'GET' ? new Subject<any>() : null;
+        if(this.cancelMap['{{operationIdOriginal}}']) {
+            handle = handle.pipe(takeUntil(this.cancelMap['{{operationIdOriginal}}']));
+        }
         if(typeof this.configuration.errorHandler === 'function') {
           return handle.pipe(catchError(err => this.configuration.errorHandler(err, '{{operationIdOriginal}}')));
         }
@@ -358,7 +370,18 @@ export class {{classname}} {
             requestOptions = (<any>Object).assign(requestOptions, extraHttpRequestParams);
         }
 
-        const handle = this.http.request(`${this.configuration.basePath}{{{path}}}`, requestOptions);
+        let handle = this.http.request(`${this.configuration.basePath}{{{path}}}`, requestOptions);
+
+        if (this.cancelMap['{{operationIdOriginal}}']) {
+            this.cancelMap['{{operationIdOriginal}}'].next();
+            this.cancelMap['{{operationIdOriginal}}'].complete();
+            this.cancelMap['{{operationIdOriginal}}'] = null;
+        }
+        this.cancelMap['{{operationIdOriginal}}'] = {{httpMethod}} === 'GET' ? new Subject<any>() : null;
+        if(this.cancelMap['{{operationIdOriginal}}']) {
+            handle = handle.takeUntil(this.cancelMap['{{operationIdOriginal}}']);
+        }
+
         if(typeof this.configuration.errorHandler === 'function') {
           return handle.catch(err => this.configuration.errorHandler(err, '{{operationIdOriginal}}'));
         }