1 files changed, 117 insertions, 0 deletions
diff --git a/node_modules/fbjs/lib/fetchWithRetries.js.flow b/node_modules/fbjs/lib/fetchWithRetries.js.flow
new file mode 100644
index 000000000..967f5c376
--- /dev/null
+++ b/node_modules/fbjs/lib/fetchWithRetries.js.flow
@@ -0,0 +1,117 @@
+/**
+ * Copyright (c) 2013-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @providesModule fetchWithRetries
+ * @typechecks
+ * @flow
+ */
+
+'use strict';
+
+const ExecutionEnvironment = require('./ExecutionEnvironment');
+
+const sprintf = require('./sprintf');
+const fetch = require('./fetch');
+const warning = require('./warning');
+
+export type InitWithRetries = {
+  body?: mixed;
+  cache?: ?string;
+  credentials?: ?string;
+  fetchTimeout?: ?number;
+  headers?: mixed;
+  method?: ?string;
+  mode?: ?string;
+  retryDelays?: ?Array<number>;
+};
+
+const DEFAULT_TIMEOUT = 15000;
+const DEFAULT_RETRIES = [1000, 3000];
+
+/**
+ * Makes a POST request to the server with the given data as the payload.
+ * Automatic retries are done based on the values in `retryDelays`.
+ */
+function fetchWithRetries(uri: string, initWithRetries?: ?InitWithRetries): Promise<any> {
+  const { fetchTimeout, retryDelays, ...init } = initWithRetries || {};
+  const _fetchTimeout = fetchTimeout != null ? fetchTimeout : DEFAULT_TIMEOUT;
+  const _retryDelays = retryDelays != null ? retryDelays : DEFAULT_RETRIES;
+
+  let requestsAttempted = 0;
+  let requestStartTime = 0;
+  return new Promise((resolve, reject) => {
+    /**
+     * Sends a request to the server that will timeout after `fetchTimeout`.
+     * If the request fails or times out a new request might be scheduled.
+     */
+    function sendTimedRequest(): void {
+      requestsAttempted++;
+      requestStartTime = Date.now();
+      let isRequestAlive = true;
+      const request = fetch(uri, init);
+      const requestTimeout = setTimeout(() => {
+        isRequestAlive = false;
+        if (shouldRetry(requestsAttempted)) {
+          warning(false, 'fetchWithRetries: HTTP timeout, retrying.');
+          retryRequest();
+        } else {
+          reject(new Error(sprintf('fetchWithRetries(): Failed to get response from server, ' + 'tried %s times.', requestsAttempted)));
+        }
+      }, _fetchTimeout);
+
+      request.then(response => {
+        clearTimeout(requestTimeout);
+        if (isRequestAlive) {
+          // We got a response, we can clear the timeout.
+          if (response.status >= 200 && response.status < 300) {
+            // Got a response code that indicates success, resolve the promise.
+            resolve(response);
+          } else if (shouldRetry(requestsAttempted)) {
+            // Fetch was not successful, retrying.
+            // TODO(#7595849): Only retry on transient HTTP errors.
+            warning(false, 'fetchWithRetries: HTTP error, retrying.'), retryRequest();
+          } else {
+            // Request was not successful, giving up.
+            const error: any = new Error(sprintf('fetchWithRetries(): Still no successful response after ' + '%s retries, giving up.', requestsAttempted));
+            error.response = response;
+            reject(error);
+          }
+        }
+      }).catch(error => {
+        clearTimeout(requestTimeout);
+        if (shouldRetry(requestsAttempted)) {
+          retryRequest();
+        } else {
+          reject(error);
+        }
+      });
+    }
+
+    /**
+     * Schedules another run of sendTimedRequest based on how much time has
+     * passed between the time the last request was sent and now.
+     */
+    function retryRequest(): void {
+      const retryDelay = _retryDelays[requestsAttempted - 1];
+      const retryStartTime = requestStartTime + retryDelay;
+      // Schedule retry for a configured duration after last request started.
+      setTimeout(sendTimedRequest, retryStartTime - Date.now());
+    }
+
+    /**
+     * Checks if another attempt should be done to send a request to the server.
+     */
+    function shouldRetry(attempt: number): boolean {
+      return ExecutionEnvironment.canUseDOM && attempt <= _retryDelays.length;
+    }
+
+    sendTimedRequest();
+  });
+}
+
+module.exports = fetchWithRetries;
+\ No newline at end of file