I am new to this whole serverless framework. I created my first serverless function as documented here https://www.npmjs.com/package/serverless#quick-start. Next when I do a "serverless invoke" it works. I am confused how this works, the questions I have around this are
There does not seem to be an API gateway created so how can it invoke?
There are also stages mentioned in the serverless.yml file, I'm not sure what these translate to
Any help on this is highly appreciated.
First of all the default code comes with the AWS template, is only having a Lambda function declared. Let me try to answer your questions inline.
There does not seem to be an API gateway created so how can it invoke?
Yes, since there is no API Gateway created, its not possible to invoke the Lambda through URLs. However, it is possible to invoke the Lambda using AWS CLI or SDKs which is what Serverless Framework is providing with "serverless invoke". To create a API Gateway, you need to add an event object to the function code as shown below.
functions:
hello:
handler: handler.hello
events:
- http:
method: get
path: hello
There are also stages mentioned in the serverless.yml file, I'm not
sure what these translate to
When you define a stage in serverless.yml file, after the deployment, it creates a stage in API Gateway including it in the API Gateway URL path as shown below.
https://your-api/<stage-you-defined>/resurce-methods
Note: that if you setup a custom certificate for API Gateway, then you have option to setup your own custom paths.
Also its important to note that, although API Gateway supported this feature to have different stages(e.g test, staging, production) of a Single API Gateway deployment, latest Serverless Framework doesn't use this feature. Instead when you define a new stages, it will deploy a whole new API Gateway with the new stage. Serverless Framework has the argument for separating the API Gateway and having a single stage to self-contain each stage for isolation.
You can attach an API gateway for invoking your lambda
Or
You can get event driven. Where your lambda gets invoked in response to some events like a new message in AWS SNS or when a new object gets created in S3
Or
You can have scheduled invocations using cloudwatch trigger events
For a comprehensive list of events that can invoke lambda see Invoking Lambda Functions
As documented in AWS Regions and Endpoints there are HTTPS endpoints for Lambda. For example, in the us-east-1 region the endpoint is https://lambda.us-east-1.amazonaws.com. This is how you're able to call a Lambda directly without the API gateway. API gateway can add additional functionality and puts a full HTTP protocol on top of a Lambda.
Related
I am working on a project and trying to use API Gateway to invoke a lambda function. The lambda function is used to update a DynamoDB item. The DynamoDB table is used to keep a running count of visitors to a web page. I need to create an API to invoke the lambda function but I'm not sure how to create the API. Any assistance is appreciated.
General steps would be:
Create AWS_PROXY integration between API Gateway and your Lambda function. The example of this is in the AWS tutorials: Set up Lambda proxy integrations in API Gatewa and in Tutorial: Build a REST API with HTTP proxy integration
Add/amend execution role to your function allowing it to access DynamoDB. This is exemplified in the AWS tutorial: Using AWS Lambda with Amazon DynamoDB.
Test the API. It can be done directly in API gateway console, or using external tools such as curl or Postman.
I figured out my issue. In my lamdba function, I needed to change the output to a JSON object. Once I made the change, I was able to get my API working. Here is a link to the fix.
I am trying to call sagemaker inference endpoint from api gateway with AWS Integration.I don't want to use lamdba in between of API gateway and sagemaker runtime. I followed this doc to setup api gateway method but it fails.
How can i call sagemaker inference endpoint from API gateway?
Web Browser ----> API Gateway ----> Sagemaker endpoint
API Gateway supports integration with AWS services directly (without the Lambda). You can follow the instructions at https://docs.aws.amazon.com/apigateway/latest/developerguide/getting-started-aws-proxy.html.
When you go to Step 4 in the instructions above, for the AWS Service option, you can choose 'SageMaker Runtime' to target the invoke endpoints.
API Gateway can be used to front an Amazon SageMaker inference endpoint as a REST API, by making use of an API Gateway feature called mapping templates. This feature makes it possible for the REST API to be integrated directly with an Amazon SageMaker runtime endpoint, thereby avoiding the use of any intermediate compute resource (such as AWS Lambda or Amazon ECS containers) to invoke the endpoint. The result is a solution that is simpler, faster, and cheaper to run. See this blog post for more detail on how to configure the API Gateway mapping templates against the Sagemaker runtime endpoint.
it's a long shot since it's an old question but somebody might end up here.
Reading the first section of the documentation about calling the inference endpoint in sagemaker, you'll find that you can only call it with a POST and pass your input data in the body.
https://docs.aws.amazon.com/sagemaker/latest/APIReference/API_runtime_InvokeEndpoint.html
So it might be that you created a GET method in API Gateway and that you need to map your request parameters to a body payload or simply set up a POST method instead.
I'm building an API using AWS API Gateway and AWS Lambda. I would like to achieve continuous delivery for this API. The path I've chosen to do it is to use CloudFormation through AWS CodePipeline. I've managed to to it for another project using Lambdas (without API Gateway), it works perfectly and it is really pleasant to use.
The issue I'm facing when deploying is that the Lambdas are properly updated but not the API definition. From what I understand, the AWS::ApiGateway::Deployment are immutable resources which means that for each deployment of the API I need to create a new AWS::ApiGateway::Deployment resource. This is not practical at all because for each of this AWS::ApiGateway::Deployment I have a new Invoke URL. This is not acceptable since I would have to either change my DNS record to the newly deployed API invoke URL or ask our API users to change the URL in their applications.
What I would like is to be able to change the API definition and the Lambdas implementations without my API users having to change anything in their applications.
How can I achieve this behavior?
I created a tutorial to highlight my issue. You can find it at: https://github.com/JonathanGailliez/aws-api-gateway-lambda-example
As per: https://forums.aws.amazon.com/thread.jspa?messageID=789869󀵭
joey-aws says:
We are currently in the process of rolling out a solution which
addresses this exact problem. In the meantime, a common workaround
would be to update something small, such as a "description" field
which could then be used to "trigger" an API Gateway deployment when
updating the CloudFormation stack.
I'll update this answer and the example repo once it's rolled out.
You could run a Cloudformation update from the command line or in the AWS console. This would change the API definitions and any lambda code without changing the unique id to access your gateway.
The other option is to put your API behind a custom domain name and then you could keep deploy a new API or stage and switch over the custom domain mapping when you are ready. The users wouldn't recognize any change.
A way to achieve that is by leveraging existing frameworks like
AWS SAM
Serverless
Claudia
I was able to achieve this by using CloudFormation template generated by troposphere and boto3 api in Python as follows:
Split the template into two parts
API definition, Method(s), IAM roles, ApiKey and Lambda (a)
Deployment, UsagePlan and UsagePlanKey (b)
Once changed Lambda code is zipped up and uploaded to S3 using boto3 api
Stack (b) is deleted
Stack (a) is updated with new resource id for the GET method connected to lambda
Stack (b) is created anew
Steps 3, 4, 5 are performed using CloudFormation boto3 api with blocking until completed.
Most importantly after all steps are done ApiKey value and stage Invoke URL remain the same, running updated Lambda code as tested with curl.
Note: it may take additional 30-60s for API to become fully functional after CloudFormation update is completed.
I already had an API Gateway API as the trigger for my AWS Lambda function. However when I tried to add another API as a trigger to the same AWS Lambda, it threw an error saying that
There was an error creating the trigger: An integration is already present on this method.
Even when I delete the trigger already present from the configuration window of Lambda, it still shows that the trigger is present.
How can I add multiple API Gateway APIs as triggers for the same lambda function ?
You can setup it via API Gateway console.
Create the Lambda function via Lambda without providing a trigger
Go to API Gateway Console
Create an API.
Create a resource and method
Select the Lambda function you want to trigger by the method
Create an other API/method
Select the Lambda function you want to trigger by the method
Since you are creating the trigger/integration via API Gateway Console, API Gateway will setup the proper permission to allow API Gateway to invoke your Lambda function on multiple APIs/methods.
In the API Gateway, we cannot make entries with the same resource name. When you have created a trigger it's already created and again you are trying to create another one. So we have to clear the previous one and then try again or else we can update it going into the API Gateway interface.
I am fairly new to AWS Lambda but sure can see the benefits of it and stumbled upon the superb framework Serverless to help me built solutions on Lambda.
I started out building solutions using AWS API Gateway but really need "internal" VPC API's and not public Internet facing API's like API GW creates.
I found that Servless indeed can expose a HTTP endpoint but I can't figure out how this is done and how the URL is created.
When I deploy the Lambda from Serverless it gives me the URL, e.g.:
https://uxezd6ry8z.execute-api.eu-west-1.amazonaws.com/dev/ping
I would like to be able to find (or create) this same http listener for already existing Lambdas so my question is how is the URL created and where is teh actual HTTP listener deployed?
You might be looking for the invoke url,
1. go to https://console.aws.amazon.com/apigateway
2. select api link (which you have deployed on aws lambda).
3. select stages in left side panel and
see the invoke url.
Adding a http listener can be done by going to your lambda function, selecting the 'triggers' tab and 'add trigger', finally selecting API Gateway - but as others mentioned this does create a public facing url.
Duh, I was in the wrong AWS logon previously so the API GW was not showing any matching Serverless API and that was why I couldn't understand how they did it...
Once I logged into the AWS account that hosts the Serverless structure I can see the API GW GET API's for the Serverless HTTP listener.