microsoft/vscode-react-native
Publicmirrored fromhttps://github.com/microsoft/vscode-react-nativeAvailable
src/cdp-proxy/debuggerEndpointHelper.ts
147lines · modecode
| 1 | // Copyright (c) Microsoft Corporation. All rights reserved. |
| 2 | // Licensed under the MIT license. See LICENSE file in the project root for details. |
| 3 | |
| 4 | import * as URL from "url"; |
| 5 | import * as ipModule from "ip"; |
| 6 | const dns = require("dns").promises; |
| 7 | import * as http from "http"; |
| 8 | import * as https from "https"; |
| 9 | import { PromiseUtil } from "../common/node/promise"; |
| 10 | |
| 11 | export class DebuggerEndpointHelper { |
| 12 | private localv4: Buffer; |
| 13 | private localv6: Buffer; |
| 14 | private promiseUtil: PromiseUtil; |
| 15 | |
| 16 | constructor() { |
| 17 | this.localv4 = ipModule.toBuffer("127.0.0.1"); |
| 18 | this.localv6 = ipModule.toBuffer("::1"); |
| 19 | this.promiseUtil = new PromiseUtil(); |
| 20 | } |
| 21 | |
| 22 | /** |
| 23 | * Attempts to retrieve the debugger websocket URL for a process listening |
| 24 | * at the given address, retrying until available. |
| 25 | * @param browserURL -- Address like `http://localhost:1234` |
| 26 | */ |
| 27 | public async retryGetWSEndpoint(browserURL: string, attemptNumber: number): Promise<string> { |
| 28 | try { |
| 29 | return await this.getWSEndpoint(browserURL); |
| 30 | } catch (e) { |
| 31 | if (attemptNumber < 1) { |
| 32 | throw new Error(`Could not connect to debug target at ${browserURL}: ${e.message}`); |
| 33 | } |
| 34 | |
| 35 | await this.promiseUtil.delay(1000); |
| 36 | return await this.retryGetWSEndpoint(browserURL, --attemptNumber); |
| 37 | } |
| 38 | } |
| 39 | |
| 40 | /** |
| 41 | * Returns the debugger websocket URL a process listening at the given address. |
| 42 | * @param browserURL -- Address like `http://localhost:1234` |
| 43 | */ |
| 44 | public async getWSEndpoint(browserURL: string): Promise<string> { |
| 45 | const jsonVersion = await this.fetchJson<{ webSocketDebuggerUrl?: string }>( |
| 46 | URL.resolve(browserURL, "/json/version") |
| 47 | ); |
| 48 | if (jsonVersion.webSocketDebuggerUrl) { |
| 49 | return jsonVersion.webSocketDebuggerUrl; |
| 50 | } |
| 51 | |
| 52 | // Chrome its top-level debugg on /json/version, while Node does not. |
| 53 | // Request both and return whichever one got us a string. |
| 54 | const jsonList = await this.fetchJson<{ webSocketDebuggerUrl: string }[]>( |
| 55 | URL.resolve(browserURL, "/json/list") |
| 56 | ); |
| 57 | if (jsonList.length) { |
| 58 | return jsonList[0].webSocketDebuggerUrl; |
| 59 | } |
| 60 | |
| 61 | throw new Error("Could not find any debuggable target"); |
| 62 | } |
| 63 | |
| 64 | /** |
| 65 | * Fetches JSON content from the given URL. |
| 66 | */ |
| 67 | private async fetchJson<T>(url: string): Promise<T> { |
| 68 | const data = await this.fetch(url); |
| 69 | return JSON.parse(data); |
| 70 | } |
| 71 | |
| 72 | /** |
| 73 | * Fetches content from the given URL. |
| 74 | */ |
| 75 | private async fetch(url: string): Promise<string> { |
| 76 | const isSecure = !url.startsWith("http://"); |
| 77 | const driver = isSecure ? https : http; |
| 78 | const targetAddressIsLoopback = await this.isLoopback(url); |
| 79 | |
| 80 | return new Promise<string>((fulfill, reject) => { |
| 81 | const requestOptions: https.RequestOptions = {}; |
| 82 | |
| 83 | if (isSecure && targetAddressIsLoopback) { |
| 84 | requestOptions.rejectUnauthorized = false; |
| 85 | } |
| 86 | |
| 87 | const request = driver.get(url, requestOptions, response => { |
| 88 | |
| 89 | let data = ""; |
| 90 | response.setEncoding("utf8"); |
| 91 | response.on("data", (chunk: string) => (data += chunk)); |
| 92 | response.on("end", () => fulfill(data)); |
| 93 | response.on("error", reject); |
| 94 | }); |
| 95 | |
| 96 | request.on("error", reject); |
| 97 | request.end(); |
| 98 | }); |
| 99 | } |
| 100 | |
| 101 | /** |
| 102 | * Gets whether the IP is a loopback address. |
| 103 | */ |
| 104 | private async isLoopback(address: string) { |
| 105 | let ipOrHostname: string; |
| 106 | try { |
| 107 | const url = new URL.URL(address); |
| 108 | // replace brackets in ipv6 addresses: |
| 109 | ipOrHostname = url.hostname.replace(/^\[|\]$/g, ""); |
| 110 | } catch { |
| 111 | ipOrHostname = address; |
| 112 | } |
| 113 | |
| 114 | if (this.isLoopbackIp(ipOrHostname)) { |
| 115 | return true; |
| 116 | } |
| 117 | |
| 118 | try { |
| 119 | const resolved = await dns.lookup(ipOrHostname); |
| 120 | return this.isLoopbackIp(resolved.address); |
| 121 | } catch { |
| 122 | return false; |
| 123 | } |
| 124 | } |
| 125 | |
| 126 | /** |
| 127 | * Checks if the given address, well-formed loopback IPs. We don't need exotic |
| 128 | * variations like `127.1` because `dns.lookup()` will resolve the proper |
| 129 | * version for us. The "right" way would be to parse the IP to an integer |
| 130 | * like Go does (https://golang.org/pkg/net/#IP.IsLoopback), but this |
| 131 | * is lightweight and works. |
| 132 | */ |
| 133 | private isLoopbackIp(ipOrLocalhost: string) { |
| 134 | if (ipOrLocalhost.toLowerCase() === "localhost") { |
| 135 | return true; |
| 136 | } |
| 137 | |
| 138 | let buf: Buffer; |
| 139 | try { |
| 140 | buf = ipModule.toBuffer(ipOrLocalhost); |
| 141 | } catch { |
| 142 | return false; |
| 143 | } |
| 144 | |
| 145 | return buf.equals(this.localv4) || buf.equals(this.localv6); |
| 146 | } |
| 147 | } |
| 148 | |