Sharing code

Architect makes it easy to share code across Lambda functions. Out of the box, with zero configuration, code is shared across Lambdas as follows:

• src/shared/ - files in this dir are shared across all Lambdas
• src/views/ - files in this dir are shared to all @http get Lambdas (if any)

Additional configuration (such as folder configuration) can be managed with the @shared and @views pragmas.

Example usage

Given a simple app.arc:

@appmyapp@httpget/post/like

Where utility code lives in ./src/shared/ and common view code in ./src/views/:

.
├── src
│ ├── http
│ │ ├── get-index
│ │ │ └── index(.js|.py|.rb)
│ │ └── post-like
│ │ └── index(.js|.py|.rb)
│ ├── shared
│ │ └── authenticate(.js|.py|.rb)
│ └── views
│ └── document(.js|.py|.rb)
└── app.arc

get-index can use shared code by requiring it from @architect/shared/<file> and views code from @architect/views/<file>:

// get-index/index.js
const auth = require('@architect/shared/authenticate')
const document = require('@architect/views/document')

# get-index/lambda.rb
require_relative './vendor/shared/authenticate'
require_relative './vendor/views/document'

# get-index/lambda.py
from vendor.shared.authenticate import foo
from vendor.views.document import bar

The post-like route has access to shared code as well, but not views because it is a post request handler, not a get handler.

// post-like/index.js
const auth = require('@architect/shared/authenticate')

# post-like/lambda.rb
require_relative './vendor/shared/authenticate'

# post-like/lambda.py
from vendor.shared.authenticate import foo

Custom shared paths

The default shared and views directories can be overridden:

@appmyapp@sharedsrcpath/to/shared@viewssrcpath/to/views

They are still required in the same way:

// get-index/index.js
const auth = require('@architect/shared/authenticate')
const document = require('@architect/views/document')

# get-index/lambda.rb
require_relative './vendor/shared/authenticate'
require_relative './vendor/views/document'

# get-index/lambda.py
from vendor.shared.authenticate import foo
from vendor.views.document import bar

Runtime details

No matter where @shared source is configured it gets copied to every Lambda. The destination is slightly different depending on runtime:

Likewise, @views runtime destinations:

Tip: the entire contents of src/shared are copied so we strongly suggest keeping the directory structure as flat as possible, and the payloads as small as possible to ensure the best performance.

Shared code dependencies

@shared and @views resources can have their own dependencies defined by package.json, requirements.txt or Gemfile. These dependencies will also be copied to corresponding Lambdas.