0

At the CLi I can do

aws lambda list-functions

and get all the functions detail

Also I can do

aws lambda list-functions --query 'Functions[*].[FunctionName]' --output text

and get a simple list of just the function names.

How can I do that in a lambda using the SDK?

I tried

exports.handler = function (event) {
  const AWS = require('aws-sdk');
  const lambda = new AWS.Lambda({ apiVersion: '2015-03-31' });
  var lambs = lambda.listFunctions(); 
  console.log(lambs);
};

and I have aws lambda full access role

But i get the output below

e,
      s3DisableBodySigning: true,
      computeChecksums: true,
      convertResponseTypes: true,
      correctClockSkew: false,
      customUserAgent: null,
      dynamoDbCrc32: true,
      systemClockOffset: 0,
      signatureVersion: 'v4',
      signatureCache: true,
      retryDelayOptions: {},
      useAccelerateEndpoint: false,
      clientSideMonitoring: false,
      endpointDiscoveryEnabled: false,
      endpointCacheSize: 1000,
      hostPrefixEnabled: true,
      stsRegionalEndpoints: null
    },
    isGlobalEndpoint: false,
    endpoint: Endpoint {
      protocol: 'https:',
      host: 'lambda.us-east-2.amazonaws.com',
      port: 443,
      hostname: 'lambda.us-east-2.amazonaws.com',
      pathname: '/',
      path: '/',
      href: 'https://lambda.us-east-2.amazonaws.com/'
    },
    _events: { apiCallAttempt: [Array], apiCall: [Array] },
    MONITOR_EVENTS_BUBBLE: [Function: EVENTS_BUBBLE],
    CALL_EVENTS_BUBBLE: [Function: CALL_EVENTS_BUBBLE],
    _clientId: 2
  },
  operation: 'listFunctions',
  params: {},
  httpRequest: HttpRequest {
    method: 'POST',
    path: '/',
    headers: {
      'User-Agent': 'aws-sdk-nodejs/2.536.0 linux/v12.13.0 exec-env/AWS_Lambda_nodejs12.x'
    },
    body: '',
    endpoint: Endpoint {
      protocol: 'https:',
      host: 'lambda.us-east-2.amazonaws.com',
      port: 443,
      hostname: 'lambda.us-east-2.amazonaws.com',
      pathname: '/',
      path: '/',
      href: 'https://lambda.us-east-2.amazonaws.com/',
      constructor: [Function]
    },
    region: 'us-east-2',
    _userAgent: 'aws-sdk-nodejs/2.536.0 linux/v12.13.0 exec-env/AWS_Lambda_nodejs12.x'
  },
  startTime: 2019-12-04T20:30:18.812Z,
  response: Response {
    request: [Circular],
    data: null,
    error: null,
    retryCount: 0,
    redirectCount: 0,
    httpResponse: HttpResponse {
      statusCode: undefined,
      headers: {},
      body: undefined,
      streaming: false,
      stream: null
    },
    maxRetries: 3,
    maxRedirects: 10
  },
  _asm: AcceptorStateMachine {
    currentState: 'validate',
    states: {
      validate: [Object],
      build: [Object],
      afterBuild: [Object],
      sign: [Object],
      retry: [Object],
      afterRetry: [Object],
      send: [Object],
      validateResponse: [Object],
      extractError: [Object],
      extractData: [Object],
      restart: [Object],
      success: [Object],
      error: [Object],
      complete: [Object]
    }
  },
  _haltHandlersOnError: false,
  _events: {
    validate: [
      [Function],
      [Function],
      [Function: VALIDATE_REGION],
      [Function: BUILD_IDEMPOTENCY_TOKENS],
      [Function: VALIDATE_PARAMETERS]
    ],
    afterBuild: [
      [Function],
      [Function: SET_CONTENT_LENGTH],
      [Function: SET_HTTP_HOST]
    ],
    restart: [ [Function: RESTART] ],
    sign: [ [Function], [Function], [Function] ],
    validateResponse: [ [Function: VALIDATE_RESPONSE], [Function] ],
    send: [ [Function] ],
    httpHeaders: [ [Function: HTTP_HEADERS] ],
    httpData: [ [Function: HTTP_DATA] ],
    httpDone: [ [Function: HTTP_DONE] ],
    retry: [
      [Function: FINALIZE_ERROR],
      [Function: INVALIDATE_CREDENTIALS],
      [Function: EXPIRED_SIGNATURE],
      [Function: CLOCK_SKEWED],
      [Function: REDIRECT],
      [Function: RETRY_CHECK],
      [Function: API_CALL_ATTEMPT_RETRY]
    ],
    afterRetry: [ [Function] ],
    build: [ [Function: buildRequest] ],
    extractData: [ [Function: extractData], [Function: extractRequestId] ],
    extractError: [ [Function: extractError], [Function: extractRequestId] ],
    httpError: [ [Function: ENOTFOUND_ERROR] ],
    success: [ [Function: API_CALL_ATTEMPT] ],
    complete: [ [Function: API_CALL] ]
  },
  emit: [Function: emit],
  API_CALL_ATTEMPT: [Function: API_CALL_ATTEMPT],
  API_CALL_ATTEMPT_RETRY: [Function: API_CALL_ATTEMPT_RETRY],
  API_CALL: [Function: API_CALL]
}END RequestId: dc9caa5c-42b1-47e9-8136-80c3fbdddbc5
REPORT RequestId: dc9caa5c-42b1-47e9-8136-80c3fbdddbc5  Duration: 45.81 ms  Billed Duration: 100 ms Memory Size: 128 MB Max Memory Used: 86 MB  

1 Answer 1

1

AWS SDK calls return an AWS.Request object, not the response to the actual API call, which typically arrives asynchronously.

You need to add a callback handler like so:

lambda.listFunctions((err, data) => {
  if (err) {
    console.err(err);
  } else {
    data.Functions.forEach(func => console.log(func.FunctionName));
  }
});

Or simply use async/await, like so (note that the enclosing function must be async):

const AWS = require('aws-sdk');
const lambda = new AWS.Lambda();

exports.handler = async (event) => {
    const funcs = await lambda.listFunctions().promise();
    funcs.Functions.forEach(func => console.log(func.FunctionName));
}

The data/funcs returned to you will be a JavaScript object including an array of functions. See the SDK reference for specifics.

Ideally, use the async/await form. It's simpler, less prone to error, and more modern.

Sign up to request clarification or add additional context in comments.

Comments

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.