tencentcloud-sdk-nodejs
Version:
93 lines (92 loc) • 2.85 kB
JavaScript
import { EventEmitter } from "events";
import { createInterface } from "readline";
class SSEEventEmitter extends EventEmitter {
}
export class SSEResponseModel {
constructor(stream) {
this.stream = stream;
this.readline = createInterface({
input: stream,
crlfDelay: Infinity,
});
this.eventSource = new SSEEventEmitter();
this.init();
}
init() {
const { stream, readline, eventSource } = this;
let lines = [];
readline.on("line", (line) => {
if (line) {
lines.push(line);
return;
}
eventSource.emit("message", this.parseSSEMessage(lines.splice(0)));
});
readline.on("close", () => {
if (lines.length > 0) {
eventSource.emit("message", this.parseSSEMessage(lines.splice(0)));
}
});
stream.on("close", () => {
eventSource.emit("close");
});
stream.on("error", (err) => {
eventSource.emit("error", err);
});
}
parseSSEMessage(lines) {
const message = {
data: "",
event: "",
id: "",
retry: undefined,
};
for (let i = 0; i < lines.length; i++) {
const line = lines[i];
const colonIndex = line.indexOf(":");
if (colonIndex <= 0)
continue;
const field = line.slice(0, colonIndex);
const value = line.slice(colonIndex + (line[colonIndex + 1] === " " ? 2 : 1));
switch (field) {
case "data":
message.data = message.data ? message.data + "\n" + value : value;
break;
case "event":
message.event = value;
break;
case "id":
message.id = value;
break;
case "retry":
const retry = parseInt(value, 10);
if (!isNaN(retry)) {
message.retry = retry;
}
break;
}
}
return message;
}
on(event, listener) {
this.eventSource.on(event, listener);
return this;
}
removeListener(event, listener) {
this.eventSource.removeListener(event, listener);
return this;
}
async *[Symbol.asyncIterator]() {
let lines = [];
for await (const line of this.readline) {
if (line) {
lines.push(line);
continue;
}
yield this.parseSSEMessage(lines.splice(0));
}
if (lines.length > 0) {
yield this.parseSSEMessage(lines.splice(0));
}
}
}