1 files changed, 52 insertions, 0 deletions
diff --git a/app/assets/javascripts/lib/utils/axios_startup_calls.js b/app/assets/javascripts/lib/utils/axios_startup_calls.js
new file mode 100644
index 00000000000..cb2e8a76c08
--- /dev/null
+++ b/app/assets/javascripts/lib/utils/axios_startup_calls.js
@@ -0,0 +1,52 @@
+import { isEmpty } from 'lodash';
+import { mergeUrlParams } from './url_utility';
+
+// We should probably not couple this utility to `gon.gitlab_url`
+// Also, this would replace occurrences that aren't at the beginning of the string
+const removeGitLabUrl = url => url.replace(gon.gitlab_url, '');
+
+const getFullUrl = req => {
+  const url = removeGitLabUrl(req.url);
+  return mergeUrlParams(req.params || {}, url);
+};
+
+const setupAxiosStartupCalls = axios => {
+  const { startup_calls: startupCalls } = window.gl || {};
+
+  if (!startupCalls || isEmpty(startupCalls)) {
+    return;
+  }
+
+  // TODO: To save performance of future axios calls, we can
+  // remove this interceptor once the "startupCalls" have been loaded
+  axios.interceptors.request.use(req => {
+    const fullUrl = getFullUrl(req);
+
+    const existing = startupCalls[fullUrl];
+
+    if (existing) {
+      // eslint-disable-next-line no-param-reassign
+      req.adapter = () =>
+        existing.fetchCall.then(res => {
+          const fetchHeaders = {};
+          res.headers.forEach((val, key) => {
+            fetchHeaders[key] = val;
+          });
+
+          // eslint-disable-next-line promise/no-nesting
+          return res.json().then(data => ({
+            data,
+            status: res.status,
+            statusText: res.statusText,
+            headers: fetchHeaders,
+            config: req,
+            request: req,
+          }));
+        });
+    }
+
+    return req;
+  });
+};
+
+export default setupAxiosStartupCalls;