DEV Community

Discussion on: Managing Multiple Functions with AWS SAM and Webpack

View post
Collapse
 
sandinosaso profile image
Sandino • • Edited

Thanks for sharing this is a great post!!.

Regarding your concern about your approach "adding a new function means touching both your template.yaml and your webpack.config.ts files." someone else figured out how to keep them in sync:

// Extract the AWS::Serverless::Function Resources as they
// are the entires we need to compile.
const { Resources } = CloudFormation.yamlParse(fs.readFileSync('template.yml'))

const entries = Object.values(Resources)
  .filter(resource => resource.Type == 'AWS::Serverless::Function')
  .filter(resource => resource.Properties.Runtime.startsWith('nodejs'))

  .map(resource => {
    const file = resource.Properties.Handler.split('.')[0]
    const prefix = resource.Properties.CodeUri.substr(9)

    return {
      name: `${prefix}/${file}`,
      entry: `${prefix}/${file}.ts`,
    }
  })

  .reduce((accumulator, resource) => {
    const { name, entry } = resource

    return Object.assign(accumulator, {
      [name]: path.resolve(entry),
    })
  }, {})

module.exports = {
  entry: entries,
  ...
}
Enter fullscreen mode Exit fullscreen mode

Here is the full config: gist.github.com/henrikbjorn/d2eef5...

I think combining both approaches is a great toolchain to have.

Thank you.

Collapse
 
elthrasher profile image
Matt Morgan •

Thanks so much for the comment. I'll definitely try this!

Collapse
 
borduhh profile image
Nick Bordeau •

Here's the Typescript version as well.

/** Interface for AWS SAM Function */
interface ISamFunction {
  Type: string;
  Properties: {
    AssumeRolePolicyDocument?: JSON;
    AutoPublishAlias?: string;
    AutoPublishCodeSha256?: string;
    CodeUri?: string;
    Description?: string;
    Environment?: {
      Variables: {
        [key: string]: string;
      };
    };
    Events?: EventSource;
    FunctionName?: string;
    Handler: string;
    Layers?: { [Ref: string]: string }[];
    Runtime: string;
    Timeout?: number;
    Tracing?: string;
    VersionDescription?: string;
  };
}

const { resources } = yamlParse(readFileSync(conf.templatePath, 'utf-8'));

const entries = Object.values(resources)

  .filter((resource: ISamFunction) => resource.Type === 'AWS::Serverless::Function')

  .filter(
    (resource: ISamFunction) =>
      resource.Properties.Runtime && resource.Properties.Runtime.startsWith('nodejs')
  )

  .map((resource: ISamFunction) => ({
    filename: resource.Properties.Handler.split('.')[0],
    entryPath: resource.Properties.CodeUri.split('/').splice(3).join('/'),
  }))

  .reduce(
    (resources, resource) =>
      Object.assign(resources, {
        [`${resource.filename}`]: `./src/${resource.entryPath}${resource.filename}.ts`,
      }),
    {}
  );
Enter fullscreen mode Exit fullscreen mode
Collapse
 
elthrasher profile image
Matt Morgan •

Nice and thanks for the reminder. Got to get around to trying this!

Thread Thread
 
elthrasher profile image
Matt Morgan •

After leaving the same silly comment twice, I finally got around to putting this in and it works great. Thanks so much for the input!