Function createParser

src/sse.ts:10–51

(onEvent: (event: SSEEvent) => void)

}

export function createParser(onEvent: (event: SSEEvent) => void) {
  let buffer = "";
  let eventType = "";
  let eventData = "";

  function dispatch() {
    if (eventData !== "" || eventType !== "") {
      onEvent({
        type: eventType || "message",
        data: eventData,
      });
      eventType = "";
      eventData = "";
    }
  }

  return {
    feed(chunk: string) {
      buffer += chunk;
      const lines = buffer.split("\n");
      buffer = lines.pop() || "";

      for (const line of lines) {
        const trimmed = line.endsWith("\r") ? line.slice(0, -1) : line;

        if (trimmed === "") {
          dispatch();
        } else if (trimmed.startsWith("data: ")) {
          eventData += (eventData ? "\n" : "") + trimmed.slice(6);
        } else if (trimmed.startsWith("event: ")) {
          eventType = trimmed.slice(7);
        } else if (trimmed.startsWith("id: ")) {
          // ignore id
        } else if (trimmed.startsWith("retry: ")) {
          // ignore retry
        } else if (trimmed.startsWith(":")) {
          // comment, ignore
        }
      }
    },
  };
}

/**
 * 读取 ReadableStream 并逐块喂给 SSE 解析器，最后 resolve