begin to support JSON export

src/js/core/ConfigFactory.js

@@ -223,7 +223,7 @@ var buildGoogleFeedURL = function(key, api_version) {
     }
 }
 
-async function jsonFromGoogleURL(google_url, options) {
+export async function jsonFromGoogleURL(google_url, options) {
 
     if (!options['sheets_proxy']) {
         throw new TLError("Proxy option must be set to read data from Google")

src/js/index.js

@@ -1,7 +1,4 @@
 import "../less/TL.Timeline.less"
-export { Timeline }
-from "./timeline/Timeline"
-export { parseGoogleSpreadsheetURL }
-from "./core/ConfigFactory"
-export { lookupMediaType }
-from "./media/MediaType"
+export { Timeline, exportJSON } from "./timeline/Timeline"
+export { parseGoogleSpreadsheetURL } from "./core/ConfigFactory"
+export { lookupMediaType } from "./media/MediaType"

src/js/timeline/Timeline.js

@@ -5,7 +5,7 @@ import Message from "../ui/Message"
 import { Language, fallback, loadLanguage } from "../language/Language"
 import { I18NMixins } from "../language/I18NMixins";
 import Events from "../core/Events";
-import { makeConfig } from "../core/ConfigFactory"
+import { makeConfig, jsonFromGoogleURL } from "../core/ConfigFactory"
 import { TimelineConfig } from "../core/TimelineConfig"
 import { TimeNav } from "../timenav/TimeNav"
 import * as Browser from "../core/Browser"
@@ -1018,4 +1018,14 @@ class Timeline {
 
 classMixin(Timeline, I18NMixins, Events)
 
-export { Timeline }
+async function exportJSON(url, proxy_url) {
+
+    if (!proxy_url) {
+        proxy_url = 'https://sheets-proxy.knightlab.com/proxy/'
+    }
+
+    let json = await jsonFromGoogleURL(url, {sheets_proxy: proxy_url})
+    return json
+}
+
+export { Timeline, exportJSON }