I am trying to have lambda trigger a codebuild function when it hits the point within the lambda function, here is the current code im using for lamda:
console.log('Loading function');
const aws = require('aws-sdk');
const s3 = new aws.S3();
exports.handler = async (event, context) => {
const codebuild = new aws.CodeBuild();
let body = JSON.parse(event.body);
let key = body.model;
var getParams = {
Bucket: 'bucketname', // your bucket name,
Key: key + '/config/training_parameters.json' // path to the object you're looking for
}
if (key) {
const objects = await s3.listObjects({
Bucket: 'bucketname',
Prefix: key + "/data"
}).promise();
console.log(objects)
if (objects.Contents.length == 3) {
console.log("Pushing")
await s3.getObject(getParams, function(err, data) {
if (err)
console.log(err);
if (data) {
let objectData = JSON.parse(data.Body.toString('utf-8'));
const build = {
projectName: "projname",
environmentVariablesOverride: [
{
name: 'MODEL_NAME',
value: objectData.title,
type: 'PLAINTEXT',
},
]
};
console.log(objectData.title)
codebuild.startBuild(build,function(err, data){
if (err) {
console.log(err, err.stack);
}
else {
console.log(data);
}
});
console.log("Done with codebuild")
}
}).promise();
const message = {
'message': 'Execution started successfully!',
}
return {
'statusCode': 200,
'headers': {'Content-Type': 'application/json'},
'body': JSON.stringify(message)
};
}
}
};
Specifically this part should trigger it:
codebuild.startBuild(build,function(err, data){
if (err) {
console.log(err, err.stack);
}
else {
console.log(data);
}
});
But its not, it even outputs after the function? Im thinking its something to do with promises/await/async but cant find the right solution? Any help would be appreciated.
As you pointed out the problem is related to promises. Change your code like this:
const result = await codebuild.startBuild(build).promise();
And if you configured your lambda permissions for CodeBuild it should work.
You can change your s3.getObject the same way without the callback function:
const file = await s3.getObject(getParams).promise();
console.log(file.Body);
I am new to AWS and got the following error when I tried to input data to the dynamodb invoking the lambda function between the 'API gateway' and the 'DynamoDB'.
Error:
Expected params.Item['Age'].S to be a string........
Screenshot of the Error:
Code:
I tried in the browser (CodePen) (I used the correct Invoke URL from the API gateway):
var xhr = new XMLHttpRequest();
xhr.open('POST', 'The API Invoke URL');
xhr.onreadystatechange = function(event){
console.log(event.target.response);
}
xhr.setRequestHeader('Content-Type', 'application/json');
xhr.send(JSON.stringify({age: 26, height: 71, income: 2400}));
The following lambda function is invoked when running the above code from CodePen:
There I have imported the aws-sdk and dynamodb correctly.
exports.fn = (event, context, callback) => {
const params = {
Item: {
"UserId": {
S: "user_" + Math.random()
},
"Age": {
N: event.age
},
"Height": {
N: event.height
},
"Income": {
N: event.income
}
},
TableName: "compare-yourself"
};
dynamodb.putItem(params, function(err, data) {
if (err) {
console.log(err);
callback(err);
} else {
console.log(data);
callback(null, data);
}
});
};
In the above lambda function you can observe that I have formatted the inputs as numbers but in the API gateway, in the POST integration request I have converted the inputs to strings. so the data that is passed via the lambda function is already a string. No need to format by the Lambda function, again.
Body mapper in 'POST Integration-Request':
#set($inputRoot = $input.path('$'))
{
"age" : "$inputRoot.age",
"height": "$inputRoot.height",
"income": "$inputRoot.income"
}
I need to know the reason for the above error and am happy to provide any additional information required.
Thank you in advance.
Change the params to indicate that the value of the age field is "String" and not "Numeric":
const params = {
Item: {
"UserId": {
S: "user_" + Math.random()
},
"Age": {
"S": event.age # This was previously set to "N" which causes the issue
},
"Height": {
N: event.height
},
"Income": {
N: event.income
}
},
TableName: "compare-yourself"
};
I am trying to scan the Dynamodb table form my following code, can anyone please guide me what is wrong here.
const AWS = require("aws-sdk");
const dynamodb = new AWS.DynamoDB({
region: "eu-west-1",
apiVersion: "2012-08-10"
});
exports.handler = async (event, callback) => {
const params = {
TableName: "job_Status"
};
dynamodb.scan(params, (err, data) => {
if (err) {
console.log(err);
callback(err);
} else {
console.log(data);
callback(null, data);
}
});
};
I have given full dynamodb access role to the function but still it gives me the null response. Any idea what can be wrong here?
Response:
I tried with dynaomClient which not working too.
const AWS = require("aws-sdk");
const db = new AWS.DynamoDB.DocumentClient({
region : 'eu-west-1'
});
exports.handler = async (event, callback) => {
const params = {
TableName: "job_Status"
};
db.scan(params, (err, data) => {
if (err) {
console.log(err);
callback(err);
} else {
console.log(data);
callback(null, data);
}
});
};
Your Lambda function is async but your code uses callbacks. By the time the callback is reached, your function has already been terminated because it ran asynchronously. I'd speculate that the null output you see is the return value from the Lambda function, not your console.log.
Replace your call to scan with the following:
try{
let results = await db.scan(params).promise()
console.log(results);
} catch(err){
console.log(err)
}
For more info, check out the AWS documentation about working with promises.
I am working on one node application which is using AWS. now i want to get all cognito users but as per doc it returns first 60 users but i want all users. can you assist me with this? In doc, they mentioned that pass PaginationToken (string) . but i don't know what to pass in it.
Here what i have done so far :
exports.handler = (event, context, callback) => {
const requestBody = JSON.parse(event.body);
var params = {
"UserPoolId": "****************",
"Limit": 60,
"PaginationToken" : (what to pass here????),
}
const cognitoidentityserviceprovider = new AWS.CognitoIdentityServiceProvider();
cognitoidentityserviceprovider.listUsers(params, (err, data) => {
if (err) {
callback(null, { headers: { "Content-Type": "application/json", "Access-Control-Allow-Origin": "*" }, body: JSON.stringify({ statusCode: 405, data: err }) });
} else {
console.log(data);
let userdata = [];
for(let i=0; i<data.Users.length;i++){
// console.log(data.Users[i].Attributes);
userdata.push(getAttributes(data.Users[i].Attributes));
}
callback(null, { headers: { "Content-Type": "application/json", "Access-Control-Allow-Origin": "*" }, body: JSON.stringify({ statusCode: 200, data: userdata }) });
}
});
};
function getAttributes(attributes){
let jsonObj = {};
attributes.forEach((obj) => {
jsonObj[obj.Name] = obj.Value;
});
return jsonObj;
}
In your response you should see a property called PaginationToken. If you make the same call but include this value in your params you will receive the next 60 users. Here's the concept:
cognitoidentityserviceprovider.listUsers(params, (err, data) => {
// data.Users is the first 60 users
params.PaginationToken = data.PaginationToken;
cognitoidentityserviceprovider.listUsers(params, (err, data) => {
// data.Users is the next 60 users
});
});
You might want to consider switching to promises and async/await if your environment supports it. That would make this code easier to read and write.
const data = await cognitoidentityserviceprovider.listUsers(params).promise();
params.PaginationToken = data.PaginationToken;
const data2 = await cognitoidentityserviceprovider.listUsers(params).promise();
Now day we can use the AWS StepFunctions if we want to make an lambda function to call another one.
But for now I need do support the code in production that was written before the StepFunctions time.
For that reason I need to understand how it works. I was trying to create a very simple lambda calling another lambda function trough AWS-SDk.
I have the follow serverless.yml
service: lambdaCallLambda
provider:
name: aws
runtime: nodejs6.10
functions:
hello:
handler: handler.hello
funcOne:
handler: handler.funcOne
funcTwo:
handler: handler.funcTwo
#Must install aws-sdk. #npm install --save aws-sdk
And this is the handler.js:
'use strict';
//https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Lambda.html
var Lambda = require('aws-sdk/clients/lambda');
module.exports.hello = (event, context, callback) => {
const response = {
statusCode: 200,
body: JSON.stringify({
message: 'hello',
input: event,
}),
};
callback(null, response);
};
module.exports.funcOne = (event, context, callback) => {
var text='';
var i = 0;
for (i = 0; i < 5; i++) {
text += "The number is " + i + "\n";
}
console.log(text);
//https://docs.aws.amazon.com/general/latest/gr/rande.html
const lambda = new Lambda({
region: 'us-east-1'
});
console.log('control 3');
/*
https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Lambda.html#constructor-property
To invoke a Lambda function
This operation invokes a Lambda function
https://docs.aws.amazon.com/lambda/latest/dg/API_Invoke.html
Payload - JSON that you want to provide to your Lambda function as input.
*/
var params = {
ClientContext: "lambdaCallLambda",
FunctionName: "lambdaCallLambda-dev-funcOne",
InvocationType: "Event",
LogType: "Tail",
Payload: '{"jsonKey2":123}',
Qualifier: "1"
};
lambda.invoke(params, function(err, data) {
if (err){
console.log('control error\n');
console.log(err, err.stack); // an error occurred
}
else{
console.log('control OK\n');
console.log(data); // successful response
}
/*
data = {
FunctionError: "",
LogResult: "",
Payload: <Binary String>,
StatusCode: 123
}
*/
});
};
module.exports.funcTwo = async (event, context) => {
return 2;
//return '{"funcTwo":20000}';
//console.log("funcTwo = " + event);
};
After deploy sls deploy and call funcOne I get this 2 outputs:
LOCAL:
sls invoke local --function funcOne
Serverless: INVOKING INVOKE
The number is 0
The number is 1
The number is 2
The number is 3
The number is 4
control 3
control OK
{ StatusCode: 202, Payload: '' }
Invoking remotely in AWS:
sls invoke --function funcOne
{
"errorMessage": "Unexpected token (",
"errorType": "SyntaxError",
"stackTrace": [
" ^",
"SyntaxError: Unexpected token (",
"createScript (vm.js:56:10)",
"Object.runInThisContext (vm.js:97:10)",
"Module._compile (module.js:542:28)",
"Object.Module._extensions..js (module.js:579:10)",
"Module.load (module.js:487:32)",
"tryModuleLoad (module.js:446:12)",
"Function.Module._load (module.js:438:3)",
"Module.require (module.js:497:17)",
"require (internal/module.js:20:19)"
]
}
Error --------------------------------------------------
Invoked function failed
For debugging logs, run again after setting the "SLS_DEBUG=*" environment variable.
Get Support --------------------------------------------
Docs: docs.serverless.com
Bugs: github.com/serverless/serverless/issues
Issues: forum.serverless.com
Your Environment Information -----------------------------
OS: linux
Node Version: 8.11.3
Serverless Version: 1.29.2
Does someone knows hat is happening here? Specially for the first scenario where I dont have any error.
This is what I get from the documentation
Parameters:
err (Error) — the error object returned from the request. Set to null if the request is successful.
data (Object) — the de-serialized data returned from the request. Set to null if a request error occurs. The data object has the following properties:
Status — (Integer)
It will be 202 upon success.
Update
After Eduardo Díaz suggestion -
I have changed lambda.invoke to:
lambda.invoke({
FunctionName: 'lambdaCallLambda-dev-funcOne',
Payload: JSON.stringify(event, null, 2)
}, function(error, data) {
if (error) {
console.log('control ErrorFoncOne\n');
context.done('error', error);
}
if(data.Payload){
console.log('control SuccessFoncOne\n');
context.succeed(data)
}
});
And this what I get for Local and Remote:
{
"errorMessage": "Unexpected token (",
"errorType": "SyntaxError",
"stackTrace": [
"Module.load (module.js:487:32)",
"tryModuleLoad (module.js:446:12)",
"Function.Module._load (module.js:438:3)",
"Module.require (module.js:497:17)",
"require (internal/module.js:20:19)"
]
}
It is a SyntaxError. There is a "(" somewhere.
I have found another developer with the same error here.
Note:
No error logs in CloudWatch
Try to send the event in the payload:
lambda.invoke({
FunctionName: 'name_lambda_function',
Payload: JSON.stringify(event, null, 2)
}, function(error, data) {
if (error) {
context.done('error', error);
}
if(data.Payload){
context.succeed(data.Payload)
}
});
I strongly suspect this problem is rooted in your handler signature for funcTwo:
module.exports.funcTwo = async (event, context) => {
NodeJS 6.10 does not support async/await. Node always complains about the token after the async token, for whatever reason. If you don't use a fat arrow function:
module.exports.funcTwo = async function(event, context) {
Node will complain: Unexpected token function.
Options
Deploy the function to NodeJS 8.10 instead.
Get rid of the async keyword in the handler signature.
Use a build tool (like serverless-webpack) to transpile the function down to ES6 (or lower).
Note: If you stick with the 6.10 runtime, I think you'll want to do something like context.succeed(2); or callback(null, 2);, rather than return 2;. Simply using a return statement does seem to work on 8.10.
I have found the issue. We need JSON.stringfy in the playload in lamdda.invoke method. No extra parameters are needed. Only the JSON as per the documentation.
lambda.invoke({
FunctionName: 'lambdaCallLambda-dev-funcTwo',
Payload: JSON.stringify({"jsonKey2":i})
...
From the AWS documentation for playload we have:
Payload
JSON that you want to provide to your Lambda function as input.
Note:
the async in front of the functions
lambda.invoke({
FunctionName: 'lambdaCallLambda-dev-funcTwo',
Payload: JSON.stringify({"jsonKey2":i})
}, async function(error, data) { ...
and
module.exports.funcTwo = async(event, context, callback) => { ...
Gives me this output:
Loop nb=1
Loop nb=2
Loop nb=3
Loop nb=4
Loop nb=5
{"message":"hello from funcTwo","event":{"jsonKey2":3}}
{"message":"hello from funcTwo","event":{"jsonKey2":2}}
{"message":"hello from funcTwo","event":{"jsonKey2":1}}
{"message":"hello from funcTwo","event":{"jsonKey2":5}}
{"message":"hello from funcTwo","event":{"jsonKey2":4}}
While the absence of async gives me:
Loop nb=1
Loop nb=2
Loop nb=3
Loop nb=4
Loop nb=5
{"message":"hello from funcTwo","event":{"jsonKey2":1}}
{"message":"hello from funcTwo","event":{"jsonKey2":2}}
{"message":"hello from funcTwo","event":{"jsonKey2":3}}
{"message":"hello from funcTwo","event":{"jsonKey2":4}}
{"message":"hello from funcTwo","event":{"jsonKey2":5}}
I'm going to share the handle.js code just in case someone else needs it:
'use strict';
//https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Lambda.html
var Lambda = require('aws-sdk/clients/lambda');
module.exports.hello = (event, context, callback) => {
const response = {
statusCode: 200,
body: JSON.stringify({
message: 'hello',
input: event,
}),
};
callback(null, response);
};
/*
https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Lambda.html#constructor-property
To invoke a Lambda function
This operation invokes a Lambda function
https://docs.aws.amazon.com/lambda/latest/dg/API_Invoke.html
Payload - JSON that you want to provide to your Lambda function as input.
Serverless Framework: Lambdas Invoking Lambdas
https://lorenstewart.me/2017/10/02/serverless-framework-lambdas-invoking-lambdas/
How to escape async/await hell
https://medium.freecodecamp.org/avoiding-the-async-await-hell-c77a0fb71c4c
Iterating a Loop Using Lambda
https://docs.aws.amazon.com/step-functions/latest/dg/tutorial-create-iterate-pattern-section.html
AWS Lambda “Process exited before completing request”
https://stackoverflow.com/questions/31627950/aws-lambda-process-exited-before-completing-request
Class: AWS.Lambda
https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Lambda.html#constructor-property
Invoke
https://docs.aws.amazon.com/lambda/latest/dg/API_Invoke.html#API_Invoke_RequestSyntax
Programming Model(Node.js)
https://docs.aws.amazon.com/lambda/latest/dg/programming-model.html
AWS Lambda Examples
https://docs.aws.amazon.com/sdk-for-javascript/v2/developer-guide/lambda-examples.html
*/
//The event is a file inserted in S3. This function funcOne reads the file and loop trough all quantities of products.
//Invoking a lamda function funcTwo for each process in the loop.
module.exports.funcOne = (event, context, callback) => {
//https://docs.aws.amazon.com/general/latest/gr/rande.html
const lambda = new Lambda({
region: 'us-east-1'
});
//Loop
//nbProducts = loop trough the products JSON list in S3
var nbProducts=5;
for (let i = 1; i <= nbProducts; i++) {
console.log('Loop nb='+i+'\n');
lambda.invoke({
FunctionName: 'lambdaCallLambda-dev-funcTwo',
Payload: JSON.stringify({"jsonKey2":i})
}, async function(error, data) {
if (error) {
//console.log('control ErrorFoncOne\n');
context.done('error', error);
}
if(data.Payload){
//console.log('control SuccessFoncOne\n');
console.log(data.Payload);
//context.succeed(data)
}
});
}
};
module.exports.funcTwo = async(event, context, callback) => {
callback(null, { message: 'hello from funcTwo', event });
};
just a change of one line would get you the respose
do change in params
'use strict';
//https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Lambda.html
var Lambda = require('aws-sdk/clients/lambda');
module.exports.hello = (event, context, callback) => {
const response = {
statusCode: 200,
body: JSON.stringify({
message: 'hello',
input: event,
}),
};
callback(null, response);
};
module.exports.funcOne = (event, context, callback) => {
var text='';
var i = 0;
for (i = 0; i < 5; i++) {
text += "The number is " + i + "\n";
}
console.log(text);
//https://docs.aws.amazon.com/general/latest/gr/rande.html
const lambda = new Lambda({
region: 'us-east-1'
});
console.log('control 3');
var params = {
ClientContext: "lambdaCallLambda",
FunctionName: "lambdaCallLambda-dev-funcOne",
InvocationType: "RequestResponse", /* changed this line from
"Event" to "RequestResponse"*/
LogType: "Tail",
Payload: '{"jsonKey2":123}',
Qualifier: "1"
};
lambda.invoke(params, function(err, data) {
if (err){
console.log('control error\n');
console.log(err, err.stack); // an error occurred
}
else{
console.log('control OK\n');
console.log(data); // successful response
}
/*
data = {
FunctionError: "",
LogResult: "",
Payload: <Binary String>,
StatusCode: 123
}
*/
});
};
module.exports.funcTwo = async (event, context) => {
return 2;
//return '{"funcTwo":20000}';
//console.log("funcTwo = " + event);
};