I need to fetch information from a lambda function and remove an existing trigger (EventBridge) from this lambda using CLI (script needs to do that).
Tried to use list-event-source-mappings or delete-event-source-mappings but without success.
Seems like EventBridge isn't supported yet (showing me only SQS,Kinesis,DynamoDB,MQ,MSK) but maybe I am wrong and there is a solution?
Edit:
I have a working lambda function that has associated trigger with an Eventbridge rule which was already deleted in the past. It no longer exists in my account, but, I still see it under my Lambda trigger (it also says that this rule cannot be found any more because it is deleted - again, it still appears in my Lambda trigger and I want to CLEAN it using CLI.) I wish to DELETE the association (trigger) from my Lambda, not to delete the EventBridge TARGET which is the Lambda.
The APIs you are looking for are in the EventBridge events client:
aws events list-rule-names-by-target --target-arn <lambda-arn>
aws events list-targets-by-rule --rule <rule-name-from-previous>
aws events remove-targets --rule <rule-name-from-previous> --ids <target-id-from-previous>
Note: The terminology is a bit confusing. An Event Source Mapping is the technical term for the particular polling-type Lambda integration pattern that handles the sources you mention. It is not related to EventBridge events.
You should be able to use events command:
aws events list-rule-names-by-target --target-arn <target_arn>
This will list the names of the rules that are associated with the specified target_arn. You can then use the aws events describe-rule command to get more information about each rule, including the rule id, schedule and pattern.
aws events describe-rule --name <rule_name>
Now to remove a trigger for a Lambda function in EventBridge:
aws events remove-targets --rule <rule_name> --ids <target_id>
The target_id is the unique identifier for the trigger that you want to remove, and the rule_name is the name of the rule that the trigger is associated with.
Related
I want to receive notifications from AWS Eventbridge when there's a scheduled event for my Amazon Elastic Compute Cloud (Amazon EC2) instance.
I created an Eventbridge rule and set the target to an already working SNS topic. The SNS topic is subscribed to a working Lambda function that is used for other "Cloudwatch to slack" alarms already. The eventbridge setting is as follows:
{
"source": ["aws.health"],
"detail-type": ["AWS Health Event"],
"detail": {
"service": ["EC2"],
"eventTypeCategory": ["scheduledChange"]
}
}
I already got an EC2 scheduled maintenance(reboot) notification as e-mail from AWS, but this eventbridge I created did not trigger for that and did not send any notification to the slack channel.
I am unsure now if I am missing something in the setting. I am setting it for the first time and no way to simply test it with fake input. It is supposed to work even if there is a single schedule event that appears in the top bell icon(as shown in the screenshot above), correct?
In order to find out the root cause of this issue, I suggest to take a look a the CloudWatch usage metrics for SNS. SNS reports the following metrics which might be useful for you: NumberOfMessagesPublished, NumberOfNotificationsDelivered NumberOfNotificationsFailed. If you find these metrics reported an they have a value different than 0, this means that SNS receives events from Event Bridge and the problem is somewhere else.
If you are using a Lambda to send messages to Slack, you should take a look at the logs in CloudWatch to see if the Lambda did execute successfully. You might want to check out the setup for Lambda recommended by AWS: (link)
For further debugging you may want to check out test-event-pattern CLI command.
It is supposed to work even if there is a single schedule event that appears in the top bell icon(as shown in the screenshot above), correct?
Yeah, it supposed to work even if there already is an event.
I'm having a similar issue with eventbridge rule being built with cloudformation. I had to manually go into the eventbridge rule via the AWS console and go to the trigger and select the SNS topic again. It now works. It took me a while to figure out. Can you confirm that the fix did that for you as I'm not sure how to fix this...
I have written some cronjobs in my django app and I want to schedule these jobs using AWS Lambda service. Can someone please recommend a good approach to get this done?
I will answer this based on the question's topic rather than the body, since I am not sure what the OP means with "I want to schedule these jobs using AWS Lambda".
If all you want is trigger your Lambda function based in a cronjob, you can use CloudWatch Events to achieve this. You can specify regular cron expressions or some built-in expressions that AWS makes available, like rate(1 min) will run your function every minute. You can see how to trigger a Lambda function via CloudWatch Events on the docs. See cron/rate to see all the available options.
CloudWatch Events is only one of the many options to trigger you Lambda function. Your function can react to a whole bunch of AWS Events, including S3, SQS, SNS, API Gateway, etc. You can see the full list of events here. Just pick one that fits your needs and you are good to go.
EDIT AFTER OP'S UPDATE:
Yes, what you're looking for is CloudWatch Events. Once you have the Lambda to poll your database in place, you can just create a rule in CloudWatchEvents and have your Lambda be triggered by it. Please see the following images for guidance.
Go to CloudWatch, click on Events and choose Schedule as the Event Source
(make sure to setup your own Cron expression or select the pre-defined rate values)
On the right-hand side, choose your Lambda function accordingly.
Click on "Configure Details" when you are done, give it a name, leave the "Enabled" box checked and finally click on Create.
Go back to your Lambda function and you should see it's now triggered by CloudWatch Events (column on the left-hand side)
Your lambda is now configured properly and will execute once a day.
Quick question: Is it possible to trigger the execution of a Step Function after an SQS message was sent?, if so, how would you specify it into the cloudformation yaml file?
Thanks in advance.
The first think to consider is this: do you really need to use SQS to start a Step Functions state machine? Can you use API gateway instead? Or could you write your messages to a S3 bucket and use the CloudWatch events to start a state machine?
If you must use SQS, then you will need to have a lambda function to act as a proxy. You will need to set up the queue as a lambda trigger, and you will need to write a lambda that can parse the SQS message and make the appropriate call to the Step Functions StartExecution API.
I’m on mobile, so I can’t type up the yaml right now, but if you need it, I can try to update with it later. For now, here is detailed walkthrough of how to invoke a Step Functions state machine from Lambda (including example yaml), and here is walkthrough of how to use CloudFormation to set up SQS to trigger a Lambda.
EventBridge Pipes (launched at re:Invent 2022) allows you to trigger Step Functions State Machines without need for a Lambda function.
https://docs.aws.amazon.com/eventbridge/latest/userguide/eb-pipes.html
You can find an example here:
https://github.com/aws-samples/aws-stepfunctions-examples/blob/main/sam/demo-trigger-stepfunctions-from-sqs/template.yaml
I have a Lambda function that takes a list of tasks to be run at the time specified. This time can vary.
I am using SNS to trigger another Lambda function that in turn runs the tasks.
These tasks need to be run at specified time. Is it possible to publish a message to SNS using Lambda at the specified time?
Or send the message to SNS, but SNS in turn triggers Lambda at the specified time?
Any option would do.
P.S. I know there is an option of using Cloud Watch events, but I do not want to use any more services.
It appears that your requirement is to trigger an AWS Lambda function at specific times.
This can be done by using Amazon CloudWatch Events, which can take a cron-like expression to run a Lambda function at desired time intervals or specific times. This functionality was originally in the Lambda console, but was moved to CloudWatch Events when more services added scheduling capabilities.
However, CloudWatch Events cannot trigger an Amazon SNS message. If you need SNS to trigger Lambda, then you'll need CloudWatch Events to trigger a Lambda function that sends a message to SNS (which then triggers Lambda functions). Obviously, it would be cleaner to avoid SNS altogether unless you specifically need to fan-out the message to multiple subscriptions/Lambda functions.
I have a requirement to launch a number of lambda functions on the ObjectCreated event in a number of s3 buckets. But the architecture of my application requires modularity thus, I have to create two different templates, one for my bucket creation and another for the lambdas. According to me, one way to achieve this is by using the SNS service.
SNS
we create the SNS topic in the buckets creation template and provide the ObjectCreated event to it through NotificationConfiguration property of the s3. In the lambda template we can subscribe the lambda to the above mentioned SNS topic and the lambda function will be called on the s3 ObjectCreated event.
But again the architecture does not allows using SNS.
Possible way
Is it all possible to do this without using SNS and compromising on the modularity like making two separate templates for buckets and lambdas and using their notification configuration in a third template to complete the chain.
Final Question
I can not use SNS and I want modularity, how can I call my lambda functions on the s3 event? is it even ossible with my restrictions?
thank you
You could trigger your functions straight from S3 using events in the bucket properties. http://docs.aws.amazon.com/lambda/latest/dg/with-s3-example.html
You could also use a CloudWatch Event Rule to trigger your functions. To do so:
Go to your AWs Console and select Services > CloudWatch.
Select Rules under Events on the left.
Select Create Rule.
Leave Event Pattern selected.
Select Simple Storage Service (S3) from Service Name drop down.
Select Object Level Operations from Event Type drop down.
Select Specific operation(s).
Select PutObject from drop down.
Select Specific bucket(s) by name.
Enter bucket names.
Select + Add target* on the right.
Select Lambda function to trigger.
Select Configure details at the bottom of the page.
Enter a rule name.
Finish by selecting Create rule.