microsoft/vscode-react-native
Publicmirrored from https://github.com/microsoft/vscode-react-nativeAvailable
src/cdp-proxy/debuggerEndpointHelper.ts
126lines · modeblame
d9c9ddcbRedMickey6 years ago | 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 | | |
| 10 | export class DebuggerEndpointHelper { | |
| 11 | private localv4: Buffer; | |
| 12 | private localv6: Buffer; | |
| 13 | | |
| 14 | constructor() { | |
| 15 | this.localv4 = ipModule.toBuffer("127.0.0.1"); | |
| 16 | this.localv6 = ipModule.toBuffer("::1"); | |
| 17 | } | |
| 18 | | |
| 19 | /** | |
| 20 | * Returns the debugger websocket URL a process listening at the given address. | |
| 21 | * @param browserURL -- Address like `http://localhost:1234` | |
| 22 | */ | |
| 23 | public async getWSEndpoint(browserURL: string): Promise<string> { | |
| 24 | const jsonVersion = await this.fetchJson<{ webSocketDebuggerUrl?: string }>( | |
| 25 | URL.resolve(browserURL, "/json/version") | |
| 26 | ); | |
| 27 | if (jsonVersion.webSocketDebuggerUrl) { | |
| 28 | return jsonVersion.webSocketDebuggerUrl; | |
| 29 | } | |
| 30 | | |
| 31 | // Chrome its top-level debugg on /json/version, while Node does not. | |
| 32 | // Request both and return whichever one got us a string. | |
| 33 | const jsonList = await this.fetchJson<{ webSocketDebuggerUrl: string }[]>( | |
| 34 | URL.resolve(browserURL, "/json/list") | |
| 35 | ); | |
| 36 | if (jsonList.length) { | |
| 37 | return jsonList[0].webSocketDebuggerUrl; | |
| 38 | } | |
| 39 | | |
| 40 | throw new Error("Could not find any debuggable target"); | |
| 41 | } | |
| 42 | | |
| 43 | /** | |
| 44 | * Fetches JSON content from the given URL. | |
| 45 | */ | |
| 46 | private async fetchJson<T>(url: string): Promise<T> { | |
| 47 | const data = await this.fetch(url); | |
| 48 | return JSON.parse(data); | |
| 49 | } | |
| 50 | | |
| 51 | /** | |
| 52 | * Fetches content from the given URL. | |
| 53 | */ | |
| 54 | private async fetch(url: string): Promise<string> { | |
| 55 | const isSecure = !url.startsWith("http://"); | |
| 56 | const driver = isSecure ? https : http; | |
| 57 | const targetAddressIsLoopback = await this.isLoopback(url); | |
| 58 | | |
| 59 | return new Promise<string>((fulfill, reject) => { | |
| 60 | const requestOptions: https.RequestOptions = {}; | |
| 61 | | |
| 62 | if (isSecure && targetAddressIsLoopback) { | |
| 63 | requestOptions.rejectUnauthorized = false; | |
| 64 | } | |
| 65 | | |
| 66 | const request = driver.get(url, requestOptions, response => { | |
| 67 | | |
| 68 | let data = ""; | |
| 69 | response.setEncoding("utf8"); | |
| 70 | response.on("data", (chunk: string) => (data += chunk)); | |
| 71 | response.on("end", () => fulfill(data)); | |
| 72 | response.on("error", reject); | |
| 73 | }); | |
| 74 | | |
| 75 | request.on("error", reject); | |
| 76 | request.end(); | |
| 77 | }); | |
| 78 | } | |
| 79 | | |
| 80 | /** | |
| 81 | * Gets whether the IP is a loopback address. | |
| 82 | */ | |
| 83 | private async isLoopback(address: string) { | |
| 84 | let ipOrHostname: string; | |
| 85 | try { | |
| 86 | const url = new URL.URL(address); | |
| 87 | // replace brackets in ipv6 addresses: | |
| 88 | ipOrHostname = url.hostname.replace(/^\[|\]$/g, ""); | |
| 89 | } catch { | |
| 90 | ipOrHostname = address; | |
| 91 | } | |
| 92 | | |
| 93 | if (this.isLoopbackIp(ipOrHostname)) { | |
| 94 | return true; | |
| 95 | } | |
| 96 | | |
| 97 | try { | |
| 98 | const resolved = await dns.lookup(ipOrHostname); | |
| 99 | return this.isLoopbackIp(resolved.address); | |
| 100 | } catch { | |
| 101 | return false; | |
| 102 | } | |
| 103 | } | |
| 104 | | |
| 105 | /** | |
| 106 | * Checks if the given address, well-formed loopback IPs. We don't need exotic | |
| 107 | * variations like `127.1` because `dns.lookup()` will resolve the proper | |
| 108 | * version for us. The "right" way would be to parse the IP to an integer | |
| 109 | * like Go does (https://golang.org/pkg/net/#IP.IsLoopback), but this | |
| 110 | * is lightweight and works. | |
| 111 | */ | |
| 112 | private isLoopbackIp(ipOrLocalhost: string) { | |
| 113 | if (ipOrLocalhost.toLowerCase() === "localhost") { | |
| 114 | return true; | |
| 115 | } | |
| 116 | | |
| 117 | let buf: Buffer; | |
| 118 | try { | |
| 119 | buf = ipModule.toBuffer(ipOrLocalhost); | |
| 120 | } catch { | |
| 121 | return false; | |
| 122 | } | |
| 123 | | |
| 124 | return buf.equals(this.localv4) || buf.equals(this.localv6); | |
| 125 | } | |
| 126 | } |