public deserializeBatchRequest()

in src/table/batch/TableBatchSerialization.ts [37:134]
75 lines of code
16 McCabe index (conditional complexity)

  public deserializeBatchRequest(
    batchRequestsString: string
  ): TableBatchOperation[] {
    this.extractBatchBoundary(batchRequestsString);
    this.extractChangeSetBoundary(batchRequestsString);
    this.extractLineEndings(batchRequestsString);

    // the line endings might be \r\n or \n
    const HTTP_LINE_ENDING = this.lineEnding;
    const subRequestPrefix = `--${this.changesetBoundary}${HTTP_LINE_ENDING}`;
    const splitBody = batchRequestsString.split(subRequestPrefix);

    // dropping first element as boundary if we have a batch with multiple requests
    let subRequests: string[];
    if (splitBody.length > 1) {
      subRequests = splitBody.slice(1, splitBody.length);
    } else {
      subRequests = splitBody;
    }

    // This goes through each operation in the request and maps the content
    // of the request by deserializing it into a BatchOperation Type
    const batchOperations: TableBatchOperation[] = subRequests.map(
      (subRequest) => {
        let requestType: RegExpMatchArray | null = subRequest.match(
          "(GET|PATCH|POST|PUT|MERGE|INSERT|DELETE)"
        );
        if (requestType === null || requestType.length < 2) {
          throw new Error(
            `Couldn't extract verb from sub-Request:\n ${subRequest}`
          );
        }

        const fullRequestURI = subRequest.match(/((http+s?)(\S)+)/);
        if (fullRequestURI === null || fullRequestURI.length < 3) {
          throw new Error(
            `Couldn't extract full request URL from sub-Request:\n ${subRequest}`
          );
        }

        // extract the request path
        const path = this.extractPath(fullRequestURI[1]);
        if (path === null || path.length < 2) {
          throw new Error(
            `Couldn't extract path from URL in sub-Request:\n ${subRequest}`
          );
        }

        const jsonOperationBody = subRequest.match(/{+.+}+/);

        // Delete does not use a JSON body, but the COSMOS Table client also
        // submits requests without a JSON body for merge
        if (
          subRequests.length > 1 &&
          null !== requestType &&
          requestType[0] !== "DELETE" &&
          requestType[0] !== "MERGE" &&
          (jsonOperationBody === null || jsonOperationBody.length < 1)
        ) {
          throw new Error(
            `Couldn't extract path from sub-Request:\n ${subRequest}`
          );
        }

        let headers: string;
        let jsonBody: string;
        let subStringStart: number;
        let subStringEnd: number;
        // currently getting an invalid header in the first position
        // during table entity test for insert & merge
        subStringStart = subRequest.indexOf(fullRequestURI[1]);
        subStringStart += fullRequestURI[1].length + 1; // for the space

        if (jsonOperationBody != null) {
          // we need the jsonBody and request path extracted to be able to extract headers.
          subStringEnd = subRequest.indexOf(jsonOperationBody[0]);
          jsonBody = jsonOperationBody[0];
        } else {
          // trim "\r\n\r\n" or "\n\n" from subRequest
          subStringEnd = subRequest.length - HTTP_LINE_ENDING.length * 2;
          jsonBody = "";
        }

        headers = subRequest.substring(subStringStart, subStringEnd);

        const operation = new TableBatchOperation(headers);
        if (null !== requestType) {
          operation.httpMethod = requestType[0] as HttpMethod;
        }
        operation.path = path[1];
        operation.uri = fullRequestURI[0];
        operation.jsonRequestBody = jsonBody;
        return operation;
      }
    );

    return batchOperations;
  }