{"version":3,"file":"stream-handler.mjs","sources":["../../../src/lib/api/stream-handler.ts"],"sourcesContent":["/**\n * @file Stream Handler\n * @description Streaming response handling utilities for Server-Sent Events (SSE),\n * NDJSON streams, and custom streaming formats with subscription management.\n */\n\nimport type { StreamController, StreamEvent, StreamOptions } from './types';\n\n/**\n * Default stream options\n */\nconst DEFAULT_STREAM_OPTIONS: StreamOptions = {\n ndjson: false,\n sse: false,\n bufferSize: 1000,\n inactivityTimeout: 30000,\n};\n\n/**\n * Create a stream controller for handling streaming responses\n *\n * @typeParam T - Type of streamed data items\n * @param response - Response with readable body stream\n * @param options - Stream handling options\n * @returns Stream controller for subscribing to events\n *\n * @example\n * ```typescript\n * // NDJSON streaming\n * const stream = streamResponse(response, { ndjson: true });\n *\n * const unsubscribe = stream.subscribe((event) => {\n * if (event.type === 'data') {\n * console.log('Received:', event.data);\n * }\n * });\n *\n * // Later: cleanup\n * unsubscribe();\n * stream.abort();\n * ```\n */\nexport function streamResponse(\n response: Response | { body: ReadableStream | null },\n options: StreamOptions = {}\n): StreamController {\n const opts = { ...DEFAULT_STREAM_OPTIONS, ...options };\n const subscribers: Set<(event: StreamEvent) => void> = new Set();\n const dataBuffer: T[] = [];\n let isActive = true;\n let abortController: AbortController | null = new AbortController();\n let inactivityTimer: ReturnType | null = null;\n\n // Get the body stream\n const { body } = response;\n if (body === null || body === undefined) {\n throw new Error('Response body is not a readable stream');\n }\n\n const reader = body.getReader();\n const decoder = new TextDecoder();\n let buffer = '';\n\n // Emit event to all subscribers\n const emit = (event: StreamEvent): void => {\n for (const subscriber of subscribers) {\n subscriber(event);\n }\n };\n\n // Reset inactivity timer\n const resetInactivityTimer = (): void => {\n if (inactivityTimer !== null) {\n clearTimeout(inactivityTimer);\n }\n if (\n opts.inactivityTimeout !== undefined &&\n opts.inactivityTimeout !== null &&\n opts.inactivityTimeout > 0\n ) {\n inactivityTimer = setTimeout(() => {\n emit({\n type: 'error',\n error: new Error('Stream inactivity timeout'),\n timestamp: Date.now(),\n });\n cleanup();\n }, opts.inactivityTimeout);\n }\n };\n\n // Parse incoming data\n const parseData = (text: string): void => {\n buffer += text;\n\n if (opts.sse === true) {\n // Parse Server-Sent Events\n parseSSE(buffer, (data, remainder) => {\n buffer = remainder;\n if (data !== null && data !== undefined) {\n addData(data as T);\n }\n });\n } else if (opts.ndjson === true) {\n // Parse NDJSON (newline-delimited JSON)\n parseNDJSON(buffer, (data, remainder) => {\n buffer = remainder;\n if (data !== null && data !== undefined) {\n addData(data as T);\n }\n });\n } else if (opts.parser !== undefined) {\n // Custom parser\n const lines = buffer.split('\\n');\n buffer = lines.pop() ?? 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