Cli: Using ES syntax with Netlify Functions and Netlify Dev?

[mrlubos]

- Do you want to request a _feature_ or report a _bug_?
Feature.

- What is the current behavior?
Unable to get the ES syntax working with Netlify Functions when deployed using Netlify Dev. Netlify will either complain about unsupported import statement, or when I change my functions to use the .mjs extension and add type: "module" to package.json, it will say the function cannot be found.

- If the current behavior is a bug, please provide the steps to reproduce.
N/A

- What is the expected behavior?
I should be able to use the same ES syntax in both client code and serverless functions to increase code reusability.

- Local Environment Information
Paste the results of netlify status --verbose here

System:
    OS: macOS 10.15.3
    CPU: (16) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
  Binaries:
    Node: 12.15.0 - ~/.nvm/versions/node/v12.15.0/bin/node
    Yarn: 1.15.2 - /usr/local/bin/yarn
    npm: 6.13.4 - ~/.nvm/versions/node/v12.15.0/bin/npm
  Browsers:
    Chrome: 79.0.3945.130
    Firefox: 69.0.1
    Safari: 13.0.5

[maxcell]

Hey @mrlubos I believe you cannot use import statements within Netlify functions without compile them with webpack! I learned however, you can do that using netlify-lambda! I am writing a blog post about this very thing but short synopsis:

1. Place your functions in a folder you can later find that get built with webpack
2. In your build step, you need to do something like netlify build <folder full of lambdas you want to compile>
3. In your netlify.toml declare where your functions will be built and served from such as

So for instance my netlify.toml looks something like:

[build]
  command = "npm run build" # This commands maps to building both my gatsby blog and my functions
  functions = "functions-build" # where my functions will be located and I also link this on Netlify

[maxcell]

The reason I figured this out was through this documentation here on When to use Netlify Dev, netlify-lambda, or both

[mrlubos]

Hi @maxcell, you're right! That's why I am requesting this as a new feature, one of my requirements is to use Netlify Dev as opposed to Netlify Lambda.

[maxcell]

My bad about that one 😅, I'm not reading enough!

[mrlubos]

Thanks for looking into this issue! Hopefully somebody from Netlify will respond to it soon 🤧