How do you troubleshoot Dynamodb trigger "PROBLEM: Function call failed" or Lambda "Missing credentials in config"? - node.js

Question

I have the Lambda function below that is supposed to take changes to an existing Dynamodb table and make them to another Dynamodb table.
I purposely left the code I've tried commented out I am down to two paths both of which throw errors in different places.
If I include SharedIniFileCredentials in the code I get the following error in the Cloudwatch logs:
{
"message": "Missing credentials in config, if using AWS_CONFIG_FILE, set AWS_SDK_LOAD_CONFIG=1",
"errno": -2,
"syscall": "open",
"code": "CredentialsError",
"path": "/home/sbx_user1051/.aws/credentials",
"time": "2020-11-16T02:57:31.177Z",
"originalError": {
"message": "Could not load credentials from SharedIniFileCredentials",
"errno": -2,
"syscall": "open",
"code": "CredentialsError",
"path": "/home/sbx_user1051/.aws/credentials",
"time": "2020-11-16T02:57:31.177Z",
"originalError": {
"errno": -2,
"syscall": "open",
"code": "ENOENT",
"path": "/home/sbx_user1051/.aws/credentials",
"message": "ENOENT: no such file or directory, open '/home/sbx_user1051/.aws/credentials'"
}
}
}
If I remove that an just let the role that I created and attached (which the AWS documentation says is all I need to do) do the work for permissions I get no error in Cloudwatch logs but I see in my console statements that the putItem (or put if I use the other class) never gets executed. The code returns before it executes those functions. So if I go to the AWS console and look at the Trigger tab on my Dynamodb table I see "PROBLEM: Function call failed".
I have add environment variable. I have hard coded the key/secret into the code. I have tried running this on the command line with AWS CLI. I added environment variables. I have made sure my credentials and config files are populated correctly. Same two issues no matter what I do.
I even tried AWS CLI. If I run this on the command line with the following command
aws lambda invoke --function-name myfunction --cli-binary-format raw-in-base64-out --payload file://mynewitem2.json output.txt
I get this after a few seconds go by
Read timeout on endpoint URL: "https://lambda.us-east-2.amazonaws.com/2015-03-31/functions/myfunction/invocations"
If I add the config file statements and then re-run it on the command line I get this, but the Cloudwatch logs do not show that I reached the putItem or put commands:
{
"StatusCode": 200,
"ExecutedVersion": "$LATEST"
}
Does anyone have any suggestions here? I have looked through all the similar requests for help with no luck. I've looked at the AWS documentation over and over.
I'm completely stuck here. I must be missing something. I just don't know what it is. Do any of you??
Here is the Lambda function:
'use strict';
console.log("starting myplugin insertion . . . ");
var AWS = require("aws-sdk");
AWS.config.logger = console;
//AWS.config = new AWS.Config();
//AWS.config.accessKeyId = "...";
//AWS.config.secretAccessKey = "...";
//AWS.config.region = 'us-east-2';
//AWS.config.update({
// aws_access_key_id : '...',
// aws_secret_access_key : '...',
// region: 'us-east-2'
// });
var creds = new AWS.SharedIniFileCredentials({profile: 'myprofile'});
console.log('Creds problem: ', JSON.stringify(creds, null, 2));
AWS.config.credentials = creds;
AWS.config.getCredentials(function(err) {
if (err)
console.log('Cred problem: ', JSON.stringify(err, null, 2));
else {
console.log("Cred Access:", JSON.stringify(AWS.config.credentials, null, 2));
}
});
var ddb = new AWS.DynamoDB({
'apiVersion': '2012-08-10'
});
exports.handler = (event, context, callback) => {
console.log(JSON.stringify(event, null, 2));
event.Records.forEach((record) => {
console.log('my Stream record: ', JSON.stringify(record, null, 2));
if (record.eventName == 'INSERT') {
console.log('my INSERTING RECORD');
var params = {
TableName: 'myplugin_temp',
Item: {
"client" : record.dynamodb.NewImage.client,
"expiration" : record.dynamodb.NewImage.expiration,
"notificationurl" : record.dynamodb.NewImage.notificationurl,
"clientid" : record.dynamodb.NewImage.clientid,
"s3path" : record.dynamodb.NewImage.s3path,
"language" : record.dynamodb.NewImage.language,
"filename" : record.dynamodb.NewImage.filename,
"timecreated" : record.dynamodb.NewImage.timecreated,
"appid" : record.dynamodb.NewImage.appid,
"subtitle" : record.dynamodb.NewImage.subtitle,
"host" : record.dynamodb.NewImage.host,
"mediatype" : record.dynamodb.NewImage.mediatype,
"sourcemimtype" : record.dynamodb.NewImage.sourcemimetype,
}
};
console.log("my UP HERE");
ddb.putItem(params, function(err,data) {
console.log("my HERE");
if (err) {
console.log("my INSERTING Error", JSON.stringify(err, null, 2));
} else {
console.log("my INSERTING Success",JSON.stringify(data, null, 2));
console.log("my COMPLETED INSERTION MODULE");
}
});
}
if (record.eventName == 'REMOVE') {
console.log('my DELETING RECORD');
var params = {
TableName: 'myplugin_temp',
Item: {
"client" : record.dynamodb.NewImage.client,
"expiration" : record.dynamodb.NewImage.expiration,
"notificationurl" : record.dynamodb.NewImage.notificationurl,
"clientid" : record.dynamodb.NewImage.clientid,
"s3path" : record.dynamodb.NewImage.s3path,
"language" : record.dynamodb.NewImage.language,
"filename" : record.dynamodb.NewImage.filename,
"timecreated" : record.dynamodb.NewImage.timecreated,
"appid" : record.dynamodb.NewImage.appid,
"subtitle" : record.dynamodb.NewImage.subtitle,
"host" : record.dynamodb.NewImage.host,
"mediatype" : record.dynamodb.NewImage.mediatype,
"sourcemimtype" : record.dynamodb.NewImage.sourcemimetype,
}
};
ddb.deleteItem(params, function(err, data) {
if (err) {
console.log("my DELETING Error", JSON.stringify(err, null, 2));
} else {
console.log("my DEL Success", JSON.stringify(data, null, 2));
}
});
}
if (record.eventName == 'MODIFY') {
console.log('my MODIFYING RECORD');
var params = {
TableName: 'myplugin_temp',
Item: {
"client" : record.dynamodb.NewImage.client,
"expiration" : record.dynamodb.NewImage.expiration,
"notificationurl" : record.dynamodb.NewImage.notificationurl,
"clientid" : record.dynamodb.NewImage.clientid,
"s3path" : record.dynamodb.NewImage.s3path,
"language" : record.dynamodb.NewImage.language,
"filename" : record.dynamodb.NewImage.filename,
"timecreated" : record.dynamodb.NewImage.timecreated,
"appid" : record.dynamodb.NewImage.appid,
"subtitle" : record.dynamodb.NewImage.subtitle,
"host" : record.dynamodb.NewImage.host,
"mediatype" : record.dynamodb.NewImage.mediatype,
"sourcemimtype" : record.dynamodb.NewImage.sourcemimetype,
}
};
ddb.updateItem(params, function(err,data) {
if (err) {
console.log("my UPDATING Error", JSON.stringify(err, null, 2));
} else {
console.log("my UPDATING Success",JSON.stringify(data, null, 2));
}
});
}
});
//callback(null, `my Successfully processed records.`);
console.log(JSON.stringify(callback, null, 2));
};

Answer 1

Well, some notes to be highlighted :
AWS.SharedIniFileCredentials should load a particular path of the user home. On linux it will be on /home/[user]/.aws/credentials. While the lambda function has no access to that system path. In other words, AWS.SharedIniFileCredentials is possible to be implemented on the system which is you have access to the home directory.
Loading Credentials in Node.js from the Shared Credentials File
There are two ways to setup the permission for lambda to have access into aws services i.e dynamodb :
Creating an IAM role for lambda and add dynamodb access to the policy. Actually it should ask you to create new role policy when creating new lambda function from aws console.
How to Create an AWS IAM Policy to Grant AWS Lambda Access to an Amazon DynamoDB Table
Using IAM user keys that you have done above
Remember to have knowledge about async and sync process on javascript. On your lambda function, you miss this part there for example :
// it is a promise function that running async process
ddb.putItem(params, function(err,data) {
...
})
I would prefer to suggest change the code using the latest approach and aws promise best practice like so :
exports.handler = async (event) => {
try {
let allTasks = [];
event.Records.forEach((record) => {
// set params here
allTasks.push(ddb.putItem(params).promise());
...
})
if (allTasks.length > 0) {
return Promise.all(allTasks).then(results => {
console.log(results)
})
}
return
} catch(e) {
console.log(e)
throw e
}
}