create seperate method for getAvailableMimeTypes

src/handlers/request_handler_helper.ts

@@ -2,14 +2,12 @@ import { HTTP_STATUS_CODE, MIME_TYPE, HTTP_METHOD, HTTP_RESULT_TYPE } from "../e
 import { CONTENT_TYPE, SET_COOKIE, FORT_GLOBAL } from "../constants";
 import * as Negotiator from "negotiator";
 import { IComponentProp, IException, IFileResultInfo, IHttpResult } from "../interfaces";
-import { textResult, getResultBasedOnMiMe } from "../helpers";
+import { textResult, getResultBasedOnMiMe, getAvailableMimeTypes } from "../helpers";
 import { HttpFormatResult } from "../types";
 import { parse } from "path";
 import { FileHandler } from "./file_handler";
 
-const jsonMimeType = [MIME_TYPE.Json, MIME_TYPE.Xml];
-const textMimeType = [MIME_TYPE.Text, MIME_TYPE.Html, MIME_TYPE.Js,
-MIME_TYPE.Css, MIME_TYPE.Rtf, MIME_TYPE.Csv];
+const mimeTypeMap = new Map<string, string>();
 
 export class RequestHandlerHelper {
     protected componentProps: IComponentProp;
@@ -25,31 +23,16 @@ export class RequestHandlerHelper {
     }
 
     protected getContentTypeFromNegotiation(type: MIME_TYPE) {
-        const negotiator = new Negotiator(this.request);
-        const availableTypes: MIME_TYPE[] = this.getAvailableTypes_(type) || [type];
-        return negotiator.mediaType(availableTypes) as MIME_TYPE;
+        return this.getContentTypeFromNegotiationHavingMultipleTypes(
+            getAvailableMimeTypes(type) || [type]
+        );
     }
 
     protected getContentTypeFromNegotiationHavingMultipleTypes(types: MIME_TYPE[]) {
         const negotiator = new Negotiator(this.request);
         return negotiator.mediaType(types) as MIME_TYPE;
     }
 
-    private getAvailableTypes_(type: MIME_TYPE) {
-        switch (type) {
-            case MIME_TYPE.Json:
-            case MIME_TYPE.Xml:
-                return jsonMimeType;
-            case MIME_TYPE.Html:
-            case MIME_TYPE.Css:
-            case MIME_TYPE.Csv:
-            case MIME_TYPE.Js:
-            case MIME_TYPE.Rtf:
-            case MIME_TYPE.Text:
-                return textMimeType;
-        }
-    }
-
     protected onBadRequest(error) {
         return new FORT_GLOBAL.errorHandler().onBadRequest(error).then(data => {
             return this.onResultFromError_(data);

src/helpers/get_available_mime_type.ts

@@ -0,0 +1,20 @@
+import { MIME_TYPE } from "../enums";
+
+const jsonMimeType = [MIME_TYPE.Json, MIME_TYPE.Xml];
+const textMimeType = [MIME_TYPE.Text, MIME_TYPE.Html, MIME_TYPE.Js,
+MIME_TYPE.Css, MIME_TYPE.Rtf, MIME_TYPE.Csv];
+
+export const getAvailableMimeTypes = (type: MIME_TYPE) => {
+    switch (type) {
+        case MIME_TYPE.Json:
+        case MIME_TYPE.Xml:
+            return jsonMimeType;
+        case MIME_TYPE.Html:
+        case MIME_TYPE.Css:
+        case MIME_TYPE.Csv:
+        case MIME_TYPE.Js:
+        case MIME_TYPE.Rtf:
+        case MIME_TYPE.Text:
+            return textMimeType;
+    }
+}

src/helpers/index.ts

@@ -26,4 +26,5 @@ export * from './validate_param_guard';
 export * from './validate_body_guard';
 export * from './validate_query_shield';
 export * from './multi_format_result';
-export * from './test';
+export * from './test';
+export * from './get_available_mime_type';