protected _sign()

in device/core/src/iotedge_authentication_provider.ts [132:199]
38 lines of code
6 McCabe index (conditional complexity)

  protected _sign(resourceUri: string, expiry: number, callback: (err: Error, signature?: string) => void): void {
    // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_009: [ The _sign method shall throw a ReferenceError if the callback parameter is falsy or is not a function. ]
    if (!callback || typeof callback !== 'function') {
      throw new ReferenceError('callback cannot be \'' + callback + '\'');
    }

    // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_010: [ The _sign method invoke callback with a ReferenceError if the resourceUri parameter is falsy. ]
    if (!resourceUri) {
      callback(new ReferenceError('resourceUri cannot be \'' + resourceUri + '\''), null);
      return;
    }

    // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_011: [ The _sign method shall build the HTTP request path in the format /modules/<module id>/genid/<generation id>/sign?api-version=2018-06-28. ]

    // the request path needs to look like this:
    //  /modules/<module id>/genid/<generation id>/sign?api-version=2018-06-28
    const path = `/modules/${encodeUriComponentStrict(this._authConfig.moduleId)}/genid/${encodeUriComponentStrict(
      this._authConfig.generationId
    )}/sign?api-version=${encodeUriComponentStrict(WORKLOAD_API_VERSION)}`;

    // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_027: [** The `_sign` method shall use the `SharedAccessSignature.createWithSigningFunction` function to build the data buffer which is to be signed by iotedged.
    SharedAccessSignature.createWithSigningFunction(this._credentials, expiry, (buffer, signCallback) => {
      // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_014: [ The _sign method shall build an object with the following schema as the HTTP request body as the sign request:
      //   interface SignRequest {
      //     keyId: string;
      //     algo: string;
      //     data: string;
      //   }
      //   ]

      // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_013: [ The _sign method shall build the sign request using the following values:
      //   const signRequest = {
      //     keyId: "primary"
      //     algo: "HMACSHA256"
      //     data: `${data}\n${expiry}`
      //   };
      //   ]
      const signRequest: SignRequest = {
        keyId: DEFAULT_KEY_ID,
        algo: DEFAULT_SIGN_ALGORITHM,
        data: buffer.toString('base64')
      };

      // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_019: [ The _sign method shall invoke this._restApiClient.executeApiCall to make the REST call on iotedged using the POST method. ]
      // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_025: [** The `_sign` method shall set the HTTP request option's `request` property to use the `http.request` object.
      // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_026: [** The `_sign` method shall set the HTTP request option's `port` property to use the workload URI's port if available.
      this._restApiClient.executeApiCall(
        'POST',
        path,
        { 'Content-Type': 'application/json' },
        signRequest,
        this._getRequestOptions(),
        (err, body: SignResponse, _response) => {
          if (err) {
            signCallback(err, null);
          } else {
            // Codes_SRS_NODE_IOTEDGED_AUTHENTICATION_PROVIDER_13_015: [ The _sign method shall invoke callback when the signature is available. ]
            signCallback(null, Buffer.from(body.digest, 'base64'));
          }
        });
    }, (err, sas) => {
      if (err) {
        callback(err);
      } else {
        callback(null, sas.toString());
      }
    });
  }