I made one todo app by using lambda. I used sever-less framework for deployment. I made one post request where user can create a todo-list. For testing I am using post-man. For my Lambda function I am using async function. I can able to make post request and my item store in Dynamo db but I got response Internal server error. My goal is show in my postman what I kind of post request I made.
Here is my code:
'use strict'
const AWS = require('aws-sdk');
const uuid = require('uuid');
const dynamoDb = new AWS.DynamoDB.DocumentClient();
module.exports.createTodo = async (event) => {
const datetime = new Date().toISOString();
const data = JSON.parse(event.body);
const params = {
TableName: 'todos',
Item: {
id: uuid.v1(),
task: data.task,
done: false,
createdAt: datetime,
updatedAt: datetime
}
};
try {
let data = await dynamoDb.put(params).promise();
console.log(data);
return JSON.stringify(data); // this throw me internal server error.
} catch (error) {
console.log(error);
}
};
Since you are calling the Lambda function via API Gateway, you need to convert the response to the following structure -
return {
statusCode: 200,
body: JSON.stringify(data),
// headers: {'Content-Type': 'application/json'}, // Uncomment if needed by your client
}
Related
new to AWS and just not sure how to define the relevant authenitcation to get my lambda function to be able to call my graphQL endpoint for a post req. Assuming I need to put an API key somewhere in this function but just am a bit lost. Any help at all would be great. Have put the function below - created it using the amplify cli and the generategraphqlpermissions flag is set to true if thats any help narrowing it down.
import crypto from '#aws-crypto/sha256-js';
import { defaultProvider } from '#aws-sdk/credential-provider-node';
import { SignatureV4 } from '#aws-sdk/signature-v4';
import { HttpRequest } from '#aws-sdk/protocol-http';
import { default as fetch, Request } from 'node-fetch';
const GRAPHQL_ENDPOINT = <myEndpoint>;
const AWS_REGION = process.env.AWS_REGION || 'us-east-1';
const { Sha256 } = crypto;
const query = /* GraphQL */ `mutation CreateCalendarEvent($input: CreateCalendarEventInput!, $condition: ModelCalendarEventConditionInput) {
createCalendarEvent(input: $input, condition: $condition) {
__typename
id
start
end
title
actions
allDay
resizable
draggable
colour
createdAt
updatedAt
}
}`;
/**
* #type {import('#types/aws-lambda').APIGatewayProxyHandler}
*/
export const handler = async (event) => {
console.log(`EVENT: ${JSON.stringify(event)}`);
console.log(GRAPHQL_ENDPOINT);
const endpoint = new URL(GRAPHQL_ENDPOINT);
const signer = new SignatureV4({
credentials: defaultProvider(),
region: AWS_REGION,
service: 'appsync',
sha256: Sha256
});
const requestToBeSigned = new HttpRequest({
method: 'POST',
headers: {
'Content-Type': 'application/json',
host: endpoint.host
},
hostname: endpoint.host,
body: JSON.stringify({ query }),
path: endpoint.pathname
});
const signed = await signer.sign(requestToBeSigned);
const request = new Request(endpoint, signed);
let statusCode = 200;
let body;
let response;
try {
response = await fetch(request);
body = await response.json();
if (body.errors) statusCode = 400;
} catch (error) {
statusCode = 500;
body = {
errors: [
{
message: error.message
}
]
};
}
return {
statusCode,
// Uncomment below to enable CORS requests
// headers: {
// "Access-Control-Allow-Origin": "*",
// "Access-Control-Allow-Headers": "*"
// },
body: JSON.stringify(body)
};
};
WHen invoking an AWS Service from Lambda, you do not need the keys. Instead, you can give the IAM role that the Lambda function runs under the permissions to invoke that service. In your case, give the role permission to invoke app sync.
More information can be found here:
https://docs.aws.amazon.com/lambda/latest/dg/lambda-permissions.html
Im trying to run the United States Postal Service's Web Tools, for converting ZIP Codes into State and City. I created an AWS Lambda function inside the AWS Amplify.
But the Lambda function is always giving me the return message {"message":"Internal Server Error"}
Here is my Lambda FUnction Code.
const axios = require("axios");
const BASE_URI =
"http://production.shippingapis.com/ShippingAPITest.dll?API=CityStateLookup&XML=";
const config = {
headers: {
"Content-Type": "text/xml",
"Access-Control-Allow-Origin": "*",
"Access-Control-Allow-Credentials": true,
"Access-Control-Allow-Methods": "GET",
},
method: "get",
};
exports.handler = async function (event, context, callback) {
// The zipcode is sent by the frontend application.
// This is where we use it.
const zipcode = event.queryStringParameters.zipcode;
// The xml variable is the string we are going to send to the
// USPS to request the information
const xml = `<CityStateLookupRequest USERID="400000000"><ZipCode ID="0"><Zip5>${zipcode}</Zip5></ZipCode></CityStateLookupRequest>`;
try {
// Using syntactic sugar (async/await) we send a fetch request
// with all the required information to the USPS.
const response = await axios(`${BASE_URI}${xml}`, config);
// We first check if we got a good response. response.ok is
// saying "hey backend API, did we receive a good response?"
if (!response.ok) {
// If we did get a good response we store the response
// object in the variable
return { statusCode: response.status, body: response };
}
// Format the response as text because the USPS response is
// not JSON but XML
const data = await response.text();
// Return the response to the frontend where it will be used.
return {
statusCode: 200,
body: data,
};
// Error checking is very important because if we don't get a
// response this is what we will use to troubleshoot problems
} catch (err) {
console.log("Error: ", err);
return {
statusCode: 500,
body: JSON.stringify({ msg: err.message }),
};
}
};
The axios is working fine I think.
Any help would be appreciated as I'm trying to solve this for days now.
By default Lambda functions does not have outbound access to internet.
You can add a Nat Gateway to your VPC but it's not cheap.
Goal: Get real-time stock data from IEX API, store it in DynamoDB, use data in DynamoDB to display on site.
Edit: I want to use the pull mechanism from the API where I can pull data periodically.
Currently, on API gateway, I created a get method for my stocks resource where I set the integration type to HTTP and entered the IEX Endpoint URL as the Endpoint URL. For now, I just got the data for one stock and the JSON Response Body looks like:
{
"symbol": "AAPL",
"companyName": "Apple Inc",
"primaryExchange": "NASDAQ/NGS (GLOBAL SELECT MARKET)",
"calculationPrice": "close",
"open": 132.5,
"openTime": 1610116201607,
"openSource": "official",
"close": 132.05,
"closeTime": 1610139600449,
"closeSource": "official"
}
I want to integrate Lambda here somehow so that it can get this API data and store it in DynamoDB. So far this is what my Lambda function looks like:
'use strict';
const AWS = require('aws-sdk');
exports.handler = async (event, context) => {
const documentClient = new AWS.DynamoDB.DocumentClient();
let responseBody = "";
let statusCode = 0;
const { symbol, companyName } = JSON.parse(event.body);
const params = {
TableName: "Stocks",
Item: {
symbol: symbol,
companyName: companyName
}
};
try {
const data = await documentClient.put(params).promise();
responseBody = JSON.stringify(data);
statusCode = 201;
} catch(err) {
responseBody = `Unable to put product: ${err}`;
statusCode = 403;
}
const response = {
statusCode: statusCode,
headers: {
"Content-Type": "application/json"
},
body: responseBody
};
return response
};
How do I get the API data from API Gateway and integrate it with a Lambda function that stores this data to DynamoDB?
I have used a very simple code slightly modified from AWS provided example:
exports.handler = async (event) => {
// Load the AWS SDK for Node.js
var AWS = require('aws-sdk');
// Set region
AWS.config.update({region: 'ap-southeast-2'});
// Create publish parameters
var params = {
Message: 'This is a sample message',
Subject: 'Test SNS From Lambda',
TopicArn: 'arn:aws:sns:ap-southeast-2:577913011449:TestTopic'
};
// Create promise and SNS service object
var publishTextPromise = new AWS.SNS().publish(params).promise();
let response = {
statusCode: 200,
body: JSON.stringify('Hello from Lambda!'),
};
// Handle promise's fulfilled/rejected states
publishTextPromise.then(
function(data) {
console.log("Message ${params.Message} send sent to the topic ${params.TopicArn}");
console.log("MessageID is " + data.MessageId);
response.result = 'Success';
}).catch(
function(err) {
console.error(err, err.stack);
response.result = 'Error';
});
return response;
};
And I am getting a timeout error when testing this service. 3 seconds is the limit.
Since this is a very simply process, I suppose it shouldn't take more than 3 seconds to execute.
I have checked my IAM setting and grant my profile (admin profile) to have full access to SNS service. But the error still persists. I am wondering what is being wrong here and how should I fix this?
I am not sure why you're getting the timeout, but your code isn't supposed to work the way you might expect.
See that you're returning your response outside your .then() code, meaning that your code is going to return before your .then() code is even run (Promises are asynchronous).
Since you're already using Node 8, you're better off using async/await instead of using the old .then().catch() approach.
I have refactored your code a little bit and it works just fine. I have kept the original parameters for your convenience. See how the code is much easier to read and debug.
'use strict';
// Load the AWS SDK for Node.js
const AWS = require('aws-sdk');
// Set region
AWS.config.update({region: 'ap-southeast-2'});
const sns = new AWS.SNS()
module.exports.handler = async (event) => {
const params = {
Message: 'This is a sample message',
Subject: 'Test SNS From Lambda',
TopicArn: 'arn:aws:sns:ap-southeast-2:577913011449:TestTopic'
};
let response = {
statusCode: 200,
body: JSON.stringify('Hello from Lambda!'),
};
try {
const data = await sns.publish(params).promise();
response.messageId = data.MessageId,
response.result = 'Success'
} catch (e) {
console.log(e.stack)
response.result = 'Error'
}
return response
};
If for whatever reason you don't want to use async/await, you then need to move the return of your function inside your .then() code, as well as return as soon as the promise is invoked, like this:
'use strict';
// Load the AWS SDK for Node.js
var AWS = require('aws-sdk');
// Set region
AWS.config.update({region: 'ap-southeast-2''});
// Create publish parameters
var params = {
Message: 'This is a sample message',
Subject: 'Test SNS From Lambda',
TopicArn: 'arn:aws:sns:ap-southeast-2:577913011449:TestTopic'
};
module.exports.handler = async (event) => {
// Create promise and SNS service object
var publishTextPromise = new AWS.SNS().publish(params).promise();
let response = {
statusCode: 200,
body: JSON.stringify('Hello from Lambda!'),
};
// Handle promise's fulfilled/rejected states
return publishTextPromise.then(
function(data) {
console.log("Message ${params.Message} send sent to the topic ${params.TopicArn}");
console.log("MessageID is " + data.MessageId);
response.result = 'Success';
return response;
}).catch(
function(err) {
console.error(err, err.stack);
response.result = 'Error';
return response
});
};
I highly recommend you go with approach #1 though.
In a Lambda, I would like to sign my AppSync endpoint with aws-signature-v4 in order to use it for a mutation.
The URL generated seems to be ok but it gives me the following error when I try it:
{
"errors" : [ {
"errorType" : "InvalidSignatureException",
"message" : "The request signature we calculated does not match the signature you provided. Check your AWS Secret Access Key and signing method. Consult the service documentation for details. etc...
} ]
}
Here is my lambda function
import { Context, Callback } from 'aws-lambda';
import { GraphQLClient } from 'graphql-request';
const v4 = require('aws-signature-v4');
export async function handle(event: any, context: Context, callback: Callback) {
context.callbackWaitsForEmptyEventLoop = false;
const url = v4.createPresignedURL(
'POST',
'xxxxxxxxxxxxxxxxx.appsync-api.eu-west-1.amazonaws.com',
'/graphql',
'appsync',
'UNSIGNED-PAYLOAD',
{
key: 'yyyyyyyyyyyyyyyyyyyy',
secret: 'zzzzzzzzzzzzzzzzzzzzz',
region: 'eu-west-1'
}
);
const mutation = `{
FAKEviewProduct(title: "Inception") {
productId
}
}`;
const client = new GraphQLClient(url, {
headers: {
'Content-Type': 'application/graphql',
action: 'GetDataSource',
version: '2017-07-25'
}
});
try {
await client.request(mutation, { productId: 'jfsjfksldjfsdkjfsl' });
} catch (err) {
console.log(err);
callback(Error());
}
callback(null, {});
}
I got my key and secret by creating a new user and Allowing him appsync:GraphQL action.
What am I doing wrong?
This is how I trigger an AppSync mutation using by making a simple HTTP-request, using axios.
const AWS = require('aws-sdk');
const axios = require('axios');
exports.handler = async (event) => {
let result.data = await updateDb(event);
return result.data;
};
function updateDb({ owner, thingName, key }){
let req = new AWS.HttpRequest('https://xxxxxxxxxxx.appsync-api.eu-central-1.amazonaws.com/graphql', 'eu-central-1');
req.method = 'POST';
req.headers.host = 'xxxxxxxxxxx.appsync-api.eu-central-1.amazonaws.com';
req.headers['Content-Type'] = 'multipart/form-data';
req.body = JSON.stringify({
"query":"mutation ($input: UpdateUsersCamsInput!) { updateUsersCams(input: $input){ latestImage uid name } }",
"variables": {
"input": {
"uid": owner,
"name": thingName,
"latestImage": key
}
}
});
let signer = new AWS.Signers.V4(req, 'appsync', true);
signer.addAuthorization(AWS.config.credentials, AWS.util.date.getDate());
return axios({
method: 'post',
url: 'https://xxxxxxxxxxx.appsync-api.eu-central-1.amazonaws.com/graphql',
data: req.body,
headers: req.headers
});
}
Make sure to give the IAM-role your Lambda function is running as, permissions for appsync:GraphQL.
Adding an answer here because I had difficulty getting the accepted answer to work and I found an issue on the AWS SDK GitHub issues that said it's not recommended to use the AWS.Signers.V4 object in production. This is how I got it to work using the popular aws4 npm module that is recommended later on in the issue linked above.
const axios = require('axios');
const aws4 = require('aws4');
const query = `
query Query {
todos {
id,
title
}
}`
const sigOptions = {
method: 'POST',
host: 'xxxxxxxxxx.appsync-api.eu-west.amazonaws.com',
region: 'eu-west-1',
path: 'graphql',
body: JSON.stringify({
query
}),
service: 'appsync'
};
const creds = {
// AWS access tokens
}
axios({
url: 'https://xxxxxxxxxx.appsync-api.eu-west/graphql',
method: 'post',
headers: aws4.sign(sigOptions, creds).headers,
data: {
query
}
}).then(res => res.data))
You don't need to construct a pre-signed URL to call an AWS AppSync endpoint. Set the authentication mode on the AppSync endpoint to AWS_IAM, grant permissions to your Lambda execution role, and then follow the steps in the "Building a JavaScript Client" tutorial to invoke a mutation or query.