Creating extension repository to download the list of available extensions

src/backend/model/extension/ExtensionRepository.ts

@@ -0,0 +1,69 @@
+import {Config} from '../../../common/config/private/Config';
+import {ExtensionListItem} from '../../../common/entities/extension/ExtensionListItem';
+
+export class ExtensionRepository {
+
+  extensionsList: ExtensionListItem[];
+  lastUpdate = 0;
+  private UPDATE_FREQUENCY_MS = 30 * 1000;
+
+  public async getExtensionList() {
+    if (this.lastUpdate < Date.now() - this.UPDATE_FREQUENCY_MS) {
+      await this.fetchList();
+    }
+
+    return this.extensionsList;
+  }
+
+  private getUrlFromMDLink(text: string) {
+    if (!text) {
+      return text;
+    }
+    text = ('' + text).trim();
+    /* Match full links and relative paths */
+    // source: https://davidwells.io/snippets/regex-match-markdown-links
+    const regex = /^\[.*]\(((?:\/|https?:\/\/)[\S./?=#]+)\)$/;
+
+    if (text.match(regex).length > 0) {
+      return text.match(regex)[0].match(/https?:\/\/[\S./?=#]+/)[0].slice(0, -1);
+    }
+    return text;
+  }
+
+
+  public async fetchList() {
+    const res = await (await fetch(Config.Extensions.repositoryUrl)).text();
+    const lines = res.split('\n');
+    lines.forEach(line => line.trim());
+    const tableStartLine = lines.findIndex(l => l.startsWith('|     **Name**     |'));
+    const tableHeaderLines = 2;
+    const table = lines.slice(tableStartLine + tableHeaderLines);
+    const extensions: ExtensionListItem[] = [];
+    const getUniqueID = (name: string) => {
+      let id = name;
+      let i = 2;
+      while (extensions.findIndex(e => e.id === id) !== -1) {
+        id = name + '-' + i;
+        ++i;
+      }
+      return id;
+    };
+    table.forEach(l => {
+      const entries = l.split('|').map((l) => l.trim()).filter(e => !!e);
+      if (entries.length == 0) {
+        return;
+      }
+
+      extensions.push({
+        id: getUniqueID(entries[0]),
+        name: entries[0],
+        url: this.getUrlFromMDLink(entries[1]),
+        readme: this.getUrlFromMDLink(entries[2]),
+        zipUrl: this.getUrlFromMDLink(entries[3])
+      });
+    });
+
+    this.extensionsList = extensions;
+    this.lastUpdate = new Date().getTime();
+  }
+}

src/common/config/private/subconfigs/ServerExtensionsConfig.ts

@@ -49,6 +49,15 @@ export class ServerExtensionsEntryConfig {
 @SubConfigClass<TAGS>({softReadonly: true})
 export class ServerExtensionsConfig extends ClientExtensionsConfig {
 
+  @ConfigProperty({
+    tags: {
+      name: $localize`Repository url`,
+      priority: ConfigPriority.underTheHood
+    },
+    description: $localize`Repository url that points to a list of extensions in .md format.`,
+  })
+  repositoryUrl: string = 'https://raw.githubusercontent.com/bpatrik/pigallery2/master/extension/REPOSITORY.md';
+
   @ConfigProperty({
     tags: {
       name: $localize`Extension folder`,

src/common/entities/extension/ExtensionListItem.ts

@@ -0,0 +1,7 @@
+export interface ExtensionListItem {
+  id:string;
+  name: string;
+  url?: string;
+  readme?: string;
+  zipUrl: string;
+}