AWS released data type for HTTP resolvers recently . AuthorizationConfig The authorization config in case the HTTP endpoint requires authorization. This means that you can call AWS services . without invoking Lambda functions From Josh Kahn AWS AppSync has now been extended to support calling AWS services via HTTP data sources. In order for AWS to identify and authorize HTTP requests, they must be signed with the Signature Version 4 process . Otherwise, those requests are rejected. AWS AppSync can now calculate the signature on your behalf, based on the IAM role that’s provided as part of the HTTP data source configuration. In this post, I show an example of sending SES emails from HTTP resolvers directly. Getting started with Serverless framework The example project is based on , You need to add two plugins: and Serverless framework serverless-appsync-plugin serverless-pseudo-parameters . NOTE that serverless-appsync-plugin doesn’t support authorization config for HTTP resolvers yet. For temporary solution, you can get plugin from my forked Git repo . $ npm install serverless-pseudo-parameters
$ npm install git+https://github.com/yai333/serverless-appsync-plugin.git Edit the serverless.yml file and add the plugins to section: plugins plugins:
  - serverless-appsync-plugin
  - serverless-pseudo-parameters Define the AWS AppSync Schema Let’s look at the schema. Schema files are text files, usually named schema.graphql, I only added mutation for sending email in this example: type Mutation {
  sendNotification: String
} Define the HTTP data source Next Let’s define the AWS AppSync HTTP data source and sendNotification mutation, Add the following config to the section in serverless.yml . custom <a href="https://medium.com/media/8949588862bb8df0b7d87f1a13d377b2/href">https://medium.com/media/8949588862bb8df0b7d87f1a13d377b2/href</a> Define the IAM role for HTTP data source In this example, HTTP resolver invokes ( to send emails, you need to create an IAM role that allows HTTP resolver access to SES and send email, add following config to section in serverless.yml. Amazon Simple Email Service SES) AppSyncSESserviceRole resource <a href="https://medium.com/media/9c6cbe4537edd49672c65b0d3a0c143f/href">https://medium.com/media/9c6cbe4537edd49672c65b0d3a0c143f/href</a> Create Mapping Templates Now we have our yml configured we need to add resolvers, The mapping template files should be located in a directory called mapping-templates relative to the serverless.yml file. Let’s create the request template for send notification mutation in a file called mapping-templates/Mutation-sendNotification-reques.vtl. {
  "version": "2018-05-29",
  "method": "GET",
  "resourcePath": "/",
  "params":{
    "query":
      {
       "Action":"SendEmail",
       "Source":"noreply@neami.blue",
       "Destination.ToAddresses.member.1":"test1@email.com",
       "Destination.ToAddresses.member.2":"test2@email.com",
       "Message.Subject.Data":"test subject",
       "Message.Body.Text.Data": "test content"
      }
  }
} Then create response template mapping-templates/Mutation-sendNotification-request.vtl. #if($ctx.error)
  $util.error($ctx.error.message, $ctx.error.type)
#end

#if($ctx.result.statusCode == 200)
    $util.toJson($ctx.result)
#else
    $utils.error("Delivery failed")
#end Let’s deploy the service $ sls deploy --stage dev All set to go, Try it out! You can use the to test sendNotification mutation we just deployed. AWS AppSync console Then check whether email has been sent and received. That’s all about it, I hope you have found this article useful, You can find complete project in my . GitHub repo

Too Long; Didn't Read

Making security fun one episode at a time

Invoking AWS Services from AppSync HTTP Resolvers

Too Long; Didn't Read

Yi Ai

About Author

TOPICS

THIS ARTICLE WAS FEATURED IN...

Invoking AWS Services from AppSync HTTP Resolvers

Too Long; Didn't Read

Yi Ai

About Author

TOPICS

THIS ARTICLE WAS FEATURED IN...

RELATED STORIES