@langchain/langgraph-sdk/dist/utils/stream.cjs.map

Client library for interacting with the LangGraph API

{"version":3,"file":"stream.cjs","names":["isNetworkError"],"sources":["../../src/utils/stream.ts"],"sourcesContent":["import { isNetworkError } from \"./error.js\";\n\n// in this case don't quite match.\ntype IterableReadableStreamInterface<T> = ReadableStream<T> & AsyncIterable<T>;\n\n/**\n * Options for streaming with automatic retry logic.\n */\nexport interface StreamWithRetryOptions {\n  /**\n   * Maximum number of reconnection attempts. Default is 5.\n   */\n  maxRetries?: number;\n\n  /**\n   * AbortSignal to cancel the stream.\n   */\n  signal?: AbortSignal;\n\n  /**\n   * Callback invoked when a reconnection attempt is made.\n   */\n  onReconnect?: (options: {\n    attempt: number;\n    lastEventId?: string;\n    cause: unknown;\n  }) => void;\n}\n\n/**\n * Parameters for making a stream request\n */\nexport interface StreamRequestParams {\n  /**\n   * If provided, this is a reconnection request with the last event ID\n   */\n  lastEventId?: string;\n\n  /**\n   * Optional reconnection path from the Location header\n   */\n  reconnectPath?: string;\n}\n\n/**\n * Error thrown when maximum reconnection attempts are exceeded.\n */\nexport class MaxReconnectAttemptsError extends Error {\n  constructor(maxAttempts: number, cause: unknown) {\n    super(`Exceeded maximum SSE reconnection attempts (${maxAttempts})`);\n    this.name = \"MaxReconnectAttemptsError\";\n    this.cause = cause;\n  }\n}\n\n/**\n * Stream with automatic retry logic for SSE connections.\n * Implements reconnection behavior similar to the Python SDK.\n *\n * @param makeRequest Function to make requests. 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// release lock when stream becomes closed\n        return {\n          done: true,\n          value: undefined,\n        };\n      } else {\n        return {\n          done: false,\n          value: result.value,\n        };\n      }\n    } catch (e) {\n      this.reader.releaseLock(); // release lock when stream becomes errored\n      throw e;\n    }\n  }\n\n  async return(): Promise<IteratorResult<T>> {\n    this.ensureReader();\n    // If wrapped in a Node stream, cancel is already called.\n    if (this.locked) {\n      const cancelPromise = this.reader.cancel(); // cancel first, but don't await yet\n      this.reader.releaseLock(); // release lock first\n      await cancelPromise; // now await it\n    }\n    return { done: true, value: undefined };\n  }\n\n  // eslint-disable-next-line @typescript-eslint/no-explicit-any\n  async throw(e: any): Promise<IteratorResult<T>> {\n    this.ensureReader();\n    if (this.locked) {\n      const cancelPromise = this.reader.cancel(); // cancel first, but don't await yet\n      this.reader.releaseLock(); // release lock first\n      await cancelPromise; // now await it\n    }\n    throw e;\n  }\n\n  // eslint-disable-next-line @typescript-eslint/ban-ts-comment\n  // @ts-ignore Not present in Node 18 types, required in latest Node 22\n  async [Symbol.asyncDispose]() {\n    await this.return();\n  }\n\n  [Symbol.asyncIterator]() {\n    return this;\n  }\n\n  static fromReadableStream<T>(stream: ReadableStream<T>) {\n    // From https://developer.mozilla.org/en-US/docs/Web/API/Streams_API/Using_readable_streams#reading_the_stream\n    const reader = stream.getReader();\n    return new IterableReadableStream<T>({\n      start(controller) {\n        return pump();\n        function pump(): Promise<T | undefined> {\n          return reader.read().then(({ done, value }) => {\n            // When no more data needs to be consumed, close the stream\n            if (done) {\n              controller.close();\n              return;\n            }\n            // Enqueue the next data chunk into our target stream\n            controller.enqueue(value);\n            return pump();\n          });\n        }\n      },\n      cancel() {\n        reader.releaseLock();\n      },\n    });\n  }\n\n  static fromAsyncGenerator<T>(generator: AsyncGenerator<T>) {\n    return new IterableReadableStream<T>({\n      async pull(controller) {\n        const { value, done } = await generator.next();\n        // When no more data needs to be consumed, close the stream\n        if (done) {\n          controller.close();\n        }\n        // Fix: `else if (value)` will hang the streaming when nullish value (e.g. empty string) is pulled\n        controller.enqueue(value);\n      },\n      async cancel(reason) {\n        await generator.return(reason);\n      },\n    });\n  }\n}\n"],"mappings":";;;;;;AA+CA,IAAa,4BAAb,cAA+C,MAAM;CACnD,YAAY,aAAqB,OAAgB;AAC/C,QAAM,+CAA+C,YAAY,GAAG;AACpE,OAAK,OAAO;AACZ,OAAK,QAAQ;;;;;;;;;;;;AAajB,gBAAuB,gBACrB,aAIA,UAAkC,EAAE,EACjB;CACnB,MAAM,aAAa,QAAQ,cAAc;CACzC,IAAI,UAAU;CACd,IAAI;CACJ,IAAI;AAEJ,QAAO,MAAM;EACX,IAAI,cAAc;EAClB,IAAI;EACJ,IAAI;AAEJ,MAAI;AAEF,OAAI,QAAQ,QAAQ,QAAS;GAG7B,MAAM,EAAE,UAAU,WAAW,MAAM,YACjC,cAAc;IAAE;IAAa;IAAe,GAAG,OAChD;GAGD,MAAM,iBAAiB,SAAS,QAAQ,IAAI,WAAW;AACvD,OAAI,eACF,iBAAgB;GAIlB,MAAM,cAAc,SAAS,QAAQ,IAAI,eAAe,EAAE,MAAM,IAAI,CAAC;AACrE,OAAI,eAAe,CAAC,YAAY,SAAS,oBAAoB,CAC3D,OAAM,IAAI,MACR,8EAA8E,YAAY,GAC3F;AAGH,YAAS,OAAO,WAAW;AAE3B,OAAI;AACF,WAAO,MAAM;AAEX,SAAI,QAAQ,QAAQ,SAAS;AAC3B,YAAM,OAAO,QAAQ;AACrB;;KAGF,MAAM,EAAE,MAAM,UAAU,MAAM,OAAO,MAAM;AAE3C,SAAI,KAEF;AAIF,SAAI,MAAM,GACR,eAAc,MAAM;AAGtB,WAAM;;AAIR;YACO,OAAO;AAEd,QAAI,eAAe,iBAAiB,CAAC,QAAQ,QAAQ,QACnD,eAAc;QAEd,OAAM;aAEA;AACR,QAAI,OACF,KAAI;AACF,YAAO,aAAa;YACd;;WAKL,OAAO;AACd,eAAY;AAGZ,OACEA,6BAAe,MAAM,IACrB,eACA,iBACA,CAAC,QAAQ,QAAQ,QAEjB,eAAc;OAEd,OAAM;;AAIV,MAAI,aAAa;AACf,cAAW;AACX,OAAI,UAAU,WACZ,OAAM,IAAI,0BAA0B,YAAY,UAAU;AAI5D,WAAQ,cAAc;IAAE;IAAS;IAAa,OAAO;IAAW,CAAC;GAKjE,MAAM,QAFY,KAAK,IAAI,MAAO,MAAM,UAAU,IAAI,IAAK,GAC5C,KAAK,QAAQ,GAAG;AAG/B,SAAM,IAAI,SAAS,YAAY;AAC7B,eAAW,SAAS,MAAM;KAC1B;AAEF;;AAIF;;;AAQJ,IAAa,yBAAb,MAAa,+BACH,eAEV;CACE,AAAO;CAEP,eAAe;AACb,MAAI,CAAC,KAAK,OACR,MAAK,SAAS,KAAK,WAAW;;CAIlC,MAAM,OAAmC;AACvC,OAAK,cAAc;AACnB,MAAI;GACF,MAAM,SAAS,MAAM,KAAK,OAAO,MAAM;AACvC,OAAI,OAAO,MAAM;AACf,SAAK,OAAO,aAAa;AACzB,WAAO;KACL,MAAM;KACN,OAAO;KACR;SAED,QAAO;IACL,MAAM;IACN,OAAO,OAAO;IACf;WAEI,GAAG;AACV,QAAK,OAAO,aAAa;AACzB,SAAM;;;CAIV,MAAM,SAAqC;AACzC,OAAK,cAAc;AAEnB,MAAI,KAAK,QAAQ;GACf,MAAM,gBAAgB,KAAK,OAAO,QAAQ;AAC1C,QAAK,OAAO,aAAa;AACzB,SAAM;;AAER,SAAO;GAAE,MAAM;GAAM,OAAO;GAAW;;CAIzC,MAAM,MAAM,GAAoC;AAC9C,OAAK,cAAc;AACnB,MAAI,KAAK,QAAQ;GACf,MAAM,gBAAgB,KAAK,OAAO,QAAQ;AAC1C,QAAK,OAAO,aAAa;AACzB,SAAM;;AAER,QAAM;;CAKR,OAAO,OAAO,gBAAgB;AAC5B,QAAM,KAAK,QAAQ;;CAGrB,CAAC,OAAO,iBAAiB;AACvB,SAAO;;CAGT,OAAO,mBAAsB,QAA2B;EAEtD,MAAM,SAAS,OAAO,WAAW;AACjC,SAAO,IAAI,uBAA0B;GACnC,MAAM,YAAY;AAChB,WAAO,MAAM;IACb,SAAS,OAA+B;AACtC,YAAO,OAAO,MAAM,CAAC,MAAM,EAAE,MAAM,YAAY;AAE7C,UAAI,MAAM;AACR,kBAAW,OAAO;AAClB;;AAGF,iBAAW,QAAQ,MAAM;AACzB,aAAO,MAAM;OACb;;;GAGN,SAAS;AACP,WAAO,aAAa;;GAEvB,CAAC;;CAGJ,OAAO,mBAAsB,WAA8B;AACzD,SAAO,IAAI,uBAA0B;GACnC,MAAM,KAAK,YAAY;IACrB,MAAM,EAAE,OAAO,SAAS,MAAM,UAAU,MAAM;AAE9C,QAAI,KACF,YAAW,OAAO;AAGpB,eAAW,QAAQ,MAAM;;GAE3B,MAAM,OAAO,QAAQ;AACnB,UAAM,UAAU,OAAO,OAAO;;GAEjC,CAAC"}