Add log tailing infra and downgrade resize observer error to warn

Summary: Resize oberserver limit exceeded appears to be a benign error that we can safely ignore, added ability to change log level. Given we report errors to our user logs, fb log view and console the console log patching has been centralised and now logs are pushed to whatever destinations we have.

Reviewed By: lblasa

Differential Revision: D44666836

fbshipit-source-id: e028dbc52b00947097833f9f3619189226247e1d

desktop/flipper-ui-core/src/consoleLogTailer.tsx

@@ -0,0 +1,63 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and 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 {getStringFromErrorLike, LoggerTypes} from 'flipper-common';
+
+const logLevels: LoggerTypes[] = ['debug', 'info', 'warn', 'error'];
+
+export type LogTailer = (level: LoggerTypes, ...data: Array<any>) => void;
+
+const logTailers: LogTailer[] = [];
+
+export function addLogTailer(handler: LogTailer) {
+  logTailers.push(handler);
+}
+
+export function initLogTailer() {
+  const originalConsole: {[key: string]: any} = console;
+  //store the raw console log functions here
+  const originalConsoleLogFunctions: {[key: string]: (...args: any) => void} =
+    {} as {
+      [key: string]: (...args: any) => void;
+    };
+  // React Devtools also patches the console methods:
+  // https://github.com/facebook/react/blob/206d61f72214e8ae5b935f0bf8628491cb7f0797/packages/react-devtools-shared/src/backend/console.js#L141
+  // Not using a proxy object here because it isn't compatible with their patching process.
+  // Instead replace the methods on the console itself.
+  // Doesn't matter who patches first, single thread means it will be consistent.
+  for (const level of logLevels) {
+    const originalConsoleLogFunction = originalConsole[level];
+    originalConsoleLogFunctions[level] = originalConsoleLogFunction;
+    const overrideMethod = (...args: Array<unknown>) => {
+      const message = getStringFromErrorLike(args);
+      const newLevel = transformLogLevel(level, message);
+
+      const newConsoleLogFunction = originalConsoleLogFunctions[newLevel];
+      const result = newConsoleLogFunction(...args);
+      logTailers.forEach((handler) => {
+        handler(newLevel, ...args);
+      });
+      return result;
+    };
+
+    overrideMethod.__FLIPPER_ORIGINAL_METHOD__ = originalConsoleLogFunction;
+    originalConsole[level] = overrideMethod;
+  }
+}
+
+function transformLogLevel(level: LoggerTypes, message: string) {
+  if (
+    level === 'error' &&
+    message.includes('ResizeObserver loop limit exceeded')
+  ) {
+    return 'warn';
+  }
+
+  return level;
+}