@jovan158/vantage/dist/formats/sse.js

See and control what your coding agent does

// Server-sent events, split into the JSON of each event's data. Shared by the
// response formats that stream that way (every one Vantage reads does).
// Calls onEvent with the parsed data of every complete event. "[DONE]" and
// data that is not JSON are skipped. Frames may be split across chunks and
// may use \r\n line endings.
export function sseParser(onEvent) {
    let buffer = "";
    const decoder = new TextDecoder();
    const frame = (text) => {
        let data = "";
        for (const line of text.split(/\r?\n/)) {
            if (line.startsWith("data:"))
                data += line.slice(5).trim();
        }
        if (!data || data === "[DONE]")
            return;
        try {
            onEvent(JSON.parse(data));
        }
        catch {
            /* partial or not JSON */
        }
    };
    return {
        feed(chunk) {
            buffer += typeof chunk === "string" ? chunk : decoder.decode(chunk, { stream: true });
            buffer = buffer.replace(/\r\n/g, "\n");
            let idx;
            while ((idx = buffer.indexOf("\n\n")) !== -1) {
                const text = buffer.slice(0, idx);
                buffer = buffer.slice(idx + 2);
                if (text.trim())
                    frame(text);
            }
        },
        end() {
            if (buffer.trim())
                frame(buffer);
            buffer = "";
        },
    };
}