| 54 | } |
| 55 | |
| 56 | function parseWSFrame(buffer) { |
| 57 | // Protocol described in https://tools.ietf.org/html/rfc6455#section-5 |
| 58 | let message = null; |
| 59 | if (buffer.length < 2) |
| 60 | return { length: 0, message }; |
| 61 | if (buffer[0] === 0x88 && buffer[1] === 0x00) { |
| 62 | return { length: 2, message, closed: true }; |
| 63 | } |
| 64 | assert.strictEqual(buffer[0], 0x81); |
| 65 | let dataLen = 0x7F & buffer[1]; |
| 66 | let bodyOffset = 2; |
| 67 | if (buffer.length < bodyOffset + dataLen) |
| 68 | return 0; |
| 69 | if (dataLen === 126) { |
| 70 | dataLen = buffer.readUInt16BE(2); |
| 71 | bodyOffset = 4; |
| 72 | } else if (dataLen === 127) { |
| 73 | assert(buffer[2] === 0 && buffer[3] === 0, 'Inspector message too big'); |
| 74 | dataLen = buffer.readUIntBE(4, 6); |
| 75 | bodyOffset = 10; |
| 76 | } |
| 77 | if (buffer.length < bodyOffset + dataLen) |
| 78 | return { length: 0, message }; |
| 79 | const jsonPayload = |
| 80 | buffer.slice(bodyOffset, bodyOffset + dataLen).toString('utf8'); |
| 81 | try { |
| 82 | message = JSON.parse(jsonPayload); |
| 83 | } catch (e) { |
| 84 | console.error(`JSON.parse() failed for: ${jsonPayload}`); |
| 85 | throw e; |
| 86 | } |
| 87 | if (DEBUG) |
| 88 | console.log('[received]', JSON.stringify(message)); |
| 89 | return { length: bodyOffset + dataLen, message }; |
| 90 | } |
| 91 | |
| 92 | function formatWSFrame(message) { |
| 93 | const messageBuf = Buffer.from(JSON.stringify(message)); |