Changing functions file doesn't rebuild functions like netlify-lambda

[kentcdodds]

This basically makes netlify dev pretty worthless... Unless I'm doing something wrong 🤷‍♂️

[kentcdodds]

Ah, I just realized that netlify dev doesn't support netlify-lambda out of the box. I would seriously recommend making it basically do what netlify-lambda does. Without that I don't really have much incentive to use this as part of my regular development workflow...

[swyxio]

you're right. we do have other concerns and ideas about the right level of abstraction for this. this is a matter of ongoing debate internally as well. cc @biilmann @bcomnes

[bcomnes]

We are still brainstorming the best approach for this. For the time being, the functions directory mirrors the site deploy folder in terms of functionality. Code that lives in that folder should be ready to deploy. That spells out a few scenarios:

• Code in the functions directory is ready to ship vanilla node.js code or a self contained bundled function. We added the ability to ship an unbundled Node.js style functions, supporting hoisted and function level package.json node_module dependencies. Netlify Dev should auto-reload any changes made to code in the function directory during development, the same way it does for the build output directory or dev server it is proxying. This functionality is being added to the buildbot and will be live shortly (currently the buildbot can only deploy bundled js or zipped unbundled node.js style functions). In this arrangement, there isn't as strong of a need for netlify-lambda.

• If you want a build step on functions, you would need to stick to the functions-src -> functions-dist (or whatever your functions directory is set too) pattern, the same way you would typically build the site source directory to a output directory that we deploy. For development, you would invoke a build step with a --watch flag that would monitor your functions source directory and build into the functions deploy directory. Parallel to that Netlify dev would serve any detected changes in the deploy directory and serve those the same way. So, if you wanted your functions bundled via netlify-lambda, you would run a continuous rebuild with that, and serve the results with dev. The purpose of this separation is that netlify-lambda or webpack isn't the only way people may want to transform their lambda code. Perhaps they want to use babel-cli, or typescript tooling or something else.

In terms of netlify dev wrapping / watching / rebuilding build steps on the users behalf, we haven't finalized what exactly this looks like with respect to functions.

[bcomnes]

In terms of a preview of what we have considered here are some ideas:

• Some kind of in-place transform-api. Define a way to specify some kind of standard build api onto a function in-place (e.g. if a webpack config is found, try to load and run the nearest webpack dependency and transform it in place).
• Expand our build command api to something more sophisticated. Separate function build commands? An accompanying watch command dev can run to start file watching with rebuilding? Do we look at built asset polling and or also some kind of build server proxy?

Open to ideas and what your ideal workflow would look like.

[kentcdodds]

Hi! I'm afraid I don't have too much time to dedicate to thinking this through. But I'm sure you all will make the right choice. Good luck!

[swyxio]

netlify-lambda projects now work with netlify dev with no change using the approach added in #94, lmk if any feedback!

[kentcdodds]

Fantastic! I'll give this a try sometime!