| 1 | /** |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * |
| 4 | * This source code is licensed under the MIT license found in the |
| 5 | * LICENSE file in the root directory of this source tree. |
| 6 | * |
| 7 | * @flow |
| 8 | */ |
| 9 | |
| 10 | import Agent from './agent'; |
| 11 | |
| 12 | import type {DevToolsHook, RendererID, RendererInterface} from './types'; |
| 13 | |
| 14 | export type InitBackend = typeof initBackend; |
| 15 | |
| 16 | export function initBackend( |
| 17 | hook: DevToolsHook, |
| 18 | agent: Agent, |
| 19 | global: Object, |
| 20 | isReloadAndProfileSupported: boolean, |
| 21 | ): () => void { |
| 22 | if (hook == null) { |
| 23 | // DevTools didn't get injected into this page (maybe b'c of the contentType). |
| 24 | return () => {}; |
| 25 | } |
| 26 | |
| 27 | function registerRendererInterface( |
| 28 | id: RendererID, |
| 29 | rendererInterface: RendererInterface, |
| 30 | ) { |
| 31 | agent.registerRendererInterface(id, rendererInterface); |
| 32 | |
| 33 | // Now that the Store and the renderer interface are connected, |
| 34 | // it's time to flush the pending operation codes to the frontend. |
| 35 | rendererInterface.flushInitialOperations(); |
| 36 | } |
| 37 | |
| 38 | const subs = [ |
| 39 | hook.sub( |
| 40 | 'renderer-attached', |
| 41 | ({ |
| 42 | id, |
| 43 | rendererInterface, |
| 44 | }: { |
| 45 | id: number, |
| 46 | rendererInterface: RendererInterface, |
| 47 | }) => { |
| 48 | registerRendererInterface(id, rendererInterface); |
| 49 | }, |
| 50 | ), |
| 51 | hook.sub('unsupported-renderer-version', () => { |
| 52 | agent.onUnsupportedRenderer(); |
| 53 | }), |
| 54 | |
| 55 | hook.sub('fastRefreshScheduled', agent.onFastRefreshScheduled), |
| 56 | hook.sub('operations', agent.onHookOperations), |
| 57 | hook.sub('traceUpdates', agent.onTraceUpdates), |
| 58 | hook.sub('settingsInitialized', agent.onHookSettings), |
| 59 | |
| 60 | // TODO Add additional subscriptions required for profiling mode |
| 61 | ]; |
| 62 | |
| 63 | agent.addListener('getIfHasUnsupportedRendererVersion', () => { |
| 64 | if (hook.hasUnsupportedRendererAttached) { |
| 65 | agent.onUnsupportedRenderer(); |
| 66 | } |
| 67 | }); |
| 68 | |
| 69 | hook.rendererInterfaces.forEach((rendererInterface, id) => { |
| 70 | registerRendererInterface(id, rendererInterface); |
| 71 | }); |
| 72 | |
| 73 | hook.emit('react-devtools', agent); |
| 74 | hook.reactDevtoolsAgent = agent; |
| 75 | |
| 76 | const onAgentShutdown = () => { |
| 77 | subs.forEach(fn => fn()); |
| 78 | hook.rendererInterfaces.forEach(rendererInterface => { |
| 79 | rendererInterface.cleanup(); |
| 80 | }); |
| 81 | hook.reactDevtoolsAgent = null; |
| 82 | }; |
| 83 | |
| 84 | // Agent's event listeners are cleaned up by Agent in `shutdown` implementation. |
| 85 | agent.addListener('shutdown', onAgentShutdown); |
| 86 | agent.addListener('updateHookSettings', settings => { |
| 87 | hook.settings = settings; |
| 88 | }); |
| 89 | agent.addListener('getHookSettings', () => { |
| 90 | if (hook.settings != null) { |
| 91 | agent.onHookSettings(hook.settings); |
| 92 | } |
| 93 | }); |
| 94 | |
| 95 | if (isReloadAndProfileSupported) { |
| 96 | agent.onReloadAndProfileSupportedByHost(); |
| 97 | } |
| 98 | |
| 99 | return () => { |
| 100 | subs.forEach(fn => fn()); |
| 101 | }; |
| 102 | } |