adding some convenience

Author: Michael Spengler

test.ts

@@ -3,6 +3,16 @@ import * as log from "https://deno.land/std/log/mod.ts";
 import { assertEquals } from "https://deno.land/std/testing/asserts.ts";
 
 
+Deno.test("get time by offset", async (): Promise<void> => {
+    
+    const offset = '+02:00'
+
+    const time = await TimeService.getTimeByOffset(offset)
+
+    log.info(`The time for offset ${offset} is ${time}`)
+
+});
+
 Deno.test("get timezone", async (): Promise<void> => {
 
     const countryCode = 'DE'

time-service.ts

@@ -3,7 +3,14 @@ import * as log from "https://deno.land/std/log/mod.ts";
 
 export class TimeService {
 
-    public static readonly pathToTimeZonesFile = 'https://raw.githubusercontent.com/michael-spengler/time/master/timezones.json'
+
+    public static async getAllTimeZoneEntries(): Promise<any[]> {
+        const pathToTimeZonesFile = 'https://raw.githubusercontent.com/michael-spengler/time/master/timezones.json'
+        
+        const allTimeZoneEntries = JSON.parse(await Persistence.readFromRemoteFile(pathToTimeZonesFile))
+        
+        return allTimeZoneEntries
+    }
 
     public static async getTimeByCountryAndCity(countryCode: string, cityName: string): Promise<string> {
 
@@ -12,21 +19,9 @@ export class TimeService {
         return TimeService.getTimeByTimeZone(entry.timezone)
     }
 
-    public static async getTimeByTimeZone(timeZone: string): Promise<string> {
-
-        // const allTimeZones = JSON.parse(await Persistence.readFromLocalFile(`${Deno.cwd()}/timezones.json`))
-        const allTimeZones = JSON.parse(await Persistence.readFromRemoteFile(TimeService.pathToTimeZonesFile))
-
-        const entry = allTimeZones.filter((e: any) => e.timezone === timeZone)[0]
-
-        let minutes
-        if (TimeService.isTimeZoneInDST(timeZone)) {
-            minutes = Number(TimeService.convertOffsetToMinutes(entry.dayLightSavingTimeOffset).toString())
-        } else {
-            minutes = Number(TimeService.convertOffsetToMinutes(entry.offset).toString())
-        }
+    public static getTimeByOffset(offset: string) {
+        const minutes = Number(TimeService.convertOffsetToMinutes(offset))
 
-        log.warning(minutes)
         let getDifferenceToUtcInMilisec = minutes * 60000;
         let getUTCMilisecond = new Date().getTime();
 
@@ -36,6 +31,19 @@ export class TimeService {
         return result.substr(11, 8)
     }
 
+    public static async getTimeByTimeZone(timeZone: string): Promise<string> {
+
+        const allTimeZones = await TimeService.getAllTimeZoneEntries() 
+
+        const entry = allTimeZones.filter((e: any) => e.timezone === timeZone)[0]
+
+        if (TimeService.isTimeZoneInDST(timeZone)) {
+            return TimeService.getTimeByOffset(entry.dayLightSavingTimeOffset)
+        } else {
+            return TimeService.getTimeByOffset(entry.offset)
+        }
+    }
+
     public static isTimeZoneInDST(timeZone: string): boolean {
         return true // still figuring out a more sophisticated solution ;) 
     }
@@ -66,7 +74,7 @@ export class TimeService {
         return entry.dayLightSavingTimeOffset
     }
 
-    private static convertOffsetToMinutes(offsetString: string): number {
+    public static convertOffsetToMinutes(offsetString: string): number {
         const preFix = offsetString.substr(0, 1)
         const hours = Number(offsetString.substr(1, 2))
         const minutes = Number(offsetString.substr(4, 2))
@@ -79,8 +87,7 @@ export class TimeService {
 
     private static async getTimeZoneEntry(countryCode: string, cityName: string): Promise<any> {
 
-        // const allTimeZones = JSON.parse(await Persistence.readFromLocalFile(`${Deno.cwd()}/timezones.json`))
-        const allTimeZones = JSON.parse(await Persistence.readFromRemoteFile(TimeService.pathToTimeZonesFile))
+        const allTimeZones = await TimeService.getAllTimeZoneEntries() 
 
         const entry = allTimeZones.filter((e: any) => e.iso2 === countryCode && (e.city === cityName || e.city_ascii === cityName))[0]
         if (entry === undefined) {