Yarn workspaces

Summary:
1) moved "sonar/desktop/src" to "sonar/desktop/app/src", so "app" is now a separate package containing the core Flipper app code
2) Configured yarn workspaces with the root in "sonar/desktop": app, static, pkg, doctor, headless-tests. Plugins are not included for now, I plan to do this later.

Reviewed By: jknoxville

Differential Revision: D20535782

fbshipit-source-id: 600b2301960f37c7d72166e0d04eba462bec9fc1

desktop/app/src/dispatcher/metroDevice.tsx

@@ -0,0 +1,164 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import {Store} from '../reducers/index';
+import {Logger} from '../fb-interfaces/Logger';
+import {registerDeviceCallbackOnPlugins} from '../utils/onRegisterDevice';
+import MetroDevice from '../devices/MetroDevice';
+import {ArchivedDevice} from 'flipper';
+import http from 'http';
+
+const METRO_PORT = 8081;
+const METRO_HOST = 'localhost';
+const METRO_URL = `http://${METRO_HOST}:${METRO_PORT}`;
+const METRO_LOGS_ENDPOINT = `ws://${METRO_HOST}:${METRO_PORT}/events`;
+const METRO_MESSAGE = ['React Native packager is running', 'Metro is running'];
+const QUERY_INTERVAL = 5000;
+
+async function isMetroRunning(): Promise<boolean> {
+  return new Promise(resolve => {
+    // We use Node's http library, rather than fetch api, as the latter cannot supress network errors being shown in the devtools console
+    // which generates a lot of noise
+    http
+      .get(METRO_URL, resp => {
+        let data = '';
+        resp
+          .on('data', chunk => {
+            data += chunk;
+          })
+          .on('end', () => {
+            const isMetro = METRO_MESSAGE.some(msg => data.includes(msg));
+            resolve(isMetro);
+          });
+      })
+      .on('error', err => {
+        console.debug('Could not connect to METRO ' + err);
+        resolve(false);
+      });
+  });
+}
+
+async function registerDevice(
+  ws: WebSocket | undefined,
+  store: Store,
+  logger: Logger,
+) {
+  const metroDevice = new MetroDevice(METRO_URL, ws);
+  logger.track('usage', 'register-device', {
+    os: 'Metro',
+    name: metroDevice.title,
+  });
+
+  metroDevice.loadDevicePlugins(store.getState().plugins.devicePlugins);
+  store.dispatch({
+    type: 'REGISTER_DEVICE',
+    payload: metroDevice,
+    serial: METRO_URL,
+  });
+
+  registerDeviceCallbackOnPlugins(
+    store,
+    store.getState().plugins.devicePlugins,
+    store.getState().plugins.clientPlugins,
+    metroDevice,
+  );
+}
+
+async function unregisterDevices(store: Store, logger: Logger) {
+  logger.track('usage', 'unregister-device', {
+    os: 'Metro',
+    serial: METRO_URL,
+  });
+
+  let archivedDevice: ArchivedDevice | undefined = undefined;
+  const device = store
+    .getState()
+    .connections.devices.find(device => device.serial === METRO_URL);
+  if (device && !device.isArchived) {
+    archivedDevice = device.archive();
+  }
+
+  store.dispatch({
+    type: 'UNREGISTER_DEVICES',
+    payload: new Set([METRO_URL]),
+  });
+
+  if (archivedDevice) {
+    archivedDevice.loadDevicePlugins(store.getState().plugins.devicePlugins);
+    store.dispatch({
+      type: 'REGISTER_DEVICE',
+      payload: archivedDevice,
+    });
+  }
+}
+
+export default (store: Store, logger: Logger) => {
+  let timeoutHandle: NodeJS.Timeout;
+  let ws: WebSocket | undefined;
+  let unregistered = false;
+
+  async function tryConnectToMetro() {
+    if (ws) {
+      return;
+    }
+
+    if (await isMetroRunning()) {
+      const _ws = new WebSocket(METRO_LOGS_ENDPOINT);
+
+      _ws.onopen = () => {
+        clearTimeout(guard);
+        ws = _ws;
+        registerDevice(ws, store, logger);
+      };
+
+      _ws.onclose = _ws.onerror = () => {
+        if (!unregistered) {
+          unregistered = true;
+          clearTimeout(guard);
+          ws = undefined;
+          unregisterDevices(store, logger);
+          scheduleNext();
+        }
+      };
+
+      const guard = setTimeout(() => {
+        // Metro is running, but didn't respond to /events endpoint
+        store.dispatch({
+          type: 'SERVER_ERROR',
+          payload: {
+            message:
+              "Found a running Metro instance, but couldn't connect to the logs. Probably your React Native version is too old to support Flipper.",
+            details: `Failed to get a connection to ${METRO_LOGS_ENDPOINT} in a timely fashion`,
+            urgent: true,
+          },
+        });
+        registerDevice(undefined, store, logger);
+        // Note: no scheduleNext, we won't retry until restart
+      }, 5000);
+    } else {
+      scheduleNext();
+    }
+  }
+
+  function scheduleNext() {
+    timeoutHandle = setTimeout(tryConnectToMetro, QUERY_INTERVAL);
+  }
+
+  tryConnectToMetro();
+
+  // cleanup method
+  return () => {
+    if (ws) {
+      ws.close();
+    }
+    if (timeoutHandle) {
+      clearInterval(timeoutHandle);
+    }
+  };
+};