Function createBridgeStreamResponse

src/proxy.ts:1149–1322

Create an SSE streaming Response that reads from a live bridge.

(
  bridge: ReturnType<typeof spawnBridge>,
  heartbeatTimer: NodeJS.Timeout,
  blobStore: Map<string, Uint8Array>,
  mcpTools: McpToolDefinition[],
  modelId: string,
  bridgeKey: string,
  convKey: string,
)

/** Create an SSE streaming Response that reads from a live bridge. */
function createBridgeStreamResponse(
  bridge: ReturnType<typeof spawnBridge>,
  heartbeatTimer: NodeJS.Timeout,
  blobStore: Map<string, Uint8Array>,
  mcpTools: McpToolDefinition[],
  modelId: string,
  bridgeKey: string,
  convKey: string,
): Response {
  const completionId = `chatcmpl-${crypto.randomUUID().replace(/-/g, "").slice(0, 28)}`;
  const created = Math.floor(Date.now() / 1000);

  const stream = new ReadableStream({
    start(controller) {
      const encoder = new TextEncoder();
      let closed = false;
      const sendSSE = (data: object) => {
        if (closed) return;
        controller.enqueue(encoder.encode(`data: ${JSON.stringify(data)}\n\n`));
      };
      const sendDone = () => {
        if (closed) return;
        controller.enqueue(encoder.encode("data: [DONE]\n\n"));
      };
      const closeController = () => {
        if (closed) return;
        closed = true;
        controller.close();
      };

      const makeChunk = (
        delta: Record<string, unknown>,
        finishReason: string | null = null,
      ) => ({
        id: completionId,
        object: "chat.completion.chunk",
        created,
        model: modelId,
        choices: [{ index: 0, delta, finish_reason: finishReason }],
      });

      const makeUsageChunk = () => {
        const { prompt_tokens, completion_tokens, total_tokens } = computeUsage(state);
        return {
          id: completionId,
          object: "chat.completion.chunk",
          created,
          model: modelId,
          choices: [],
          usage: { prompt_tokens, completion_tokens, total_tokens },
        };
      };

      const state: StreamState = {
        toolCallIndex: 0,
        pendingExecs: [],
        outputTokens: 0,
        totalTokens: 0,