feat(github): add new watcher trigger

packages/backend/src/apps/github/triggers/new-watchers/new-watchers.ts

@@ -0,0 +1,75 @@
+import {
+  IGlobalVariable,
+  ITriggerOutput,
+} from '@automatisch/types';
+import getRepoOwnerAndRepo from '../../common/get-repo-owner-and-repo';
+import parseLinkHeader from '../../../../helpers/parse-header-link';
+
+const fetchWatchers = async ($: IGlobalVariable) => {
+  const repoParameter = $.step.parameters.repo as string;
+
+  if (!repoParameter) throw new Error('A repo must be set!');
+
+  const { repoOwner, repo } = getRepoOwnerAndRepo(repoParameter);
+
+  const firstPagePathname = `/repos/${repoOwner}/${repo}/subscribers`;
+  const requestConfig = {
+    params: {
+      per_page: 100
+    },
+  }
+
+  const firstPageResponse = await $.http.get(firstPagePathname, requestConfig);
+  const firstPageLinks = parseLinkHeader(firstPageResponse.headers.link);
+
+  // in case there is only single page to fetch
+  let pathname = firstPageLinks.last?.uri || firstPagePathname;
+
+  const watchers: ITriggerOutput = {
+    data: [],
+  };
+
+  do {
+    const response = await $.http.get(pathname, requestConfig);
+    const links = parseLinkHeader(response.headers.link);
+    pathname = links.prev?.uri;
+
+    if (response.integrationError) {
+      watchers.error = response.integrationError;
+      return watchers;
+    }
+
+    if (response.data.length) {
+      // to iterate reverse-chronologically
+      response.data.reverse();
+
+      for (const watcher of response.data) {
+        const watcherId = watcher.id.toString();
+
+        if ($.flow.isAlreadyProcessed(watcherId) && !$.execution.testRun) return watchers;
+
+        const dataItem = {
+          raw: watcher,
+          meta: {
+            internalId: watcherId,
+          },
+        };
+
+        watchers.data.push(dataItem);
+      }
+    }
+  } while (pathname && !$.execution.testRun === false);
+
+  return watchers;
+}
+
+const newWatchers = async ($: IGlobalVariable) => {
+  const watchers = await fetchWatchers($);
+
+  // to process chronologically
+  watchers.data.reverse();
+
+  return watchers;
+};
+
+export default newWatchers;