Documentation on node.js functions

[paulbatum]

From @cesarvarela on January 14, 2017 3:12

Can't find where is the convention for how node.js based functions should be defined. Does the main entry point must be called index.js? does it have to be specified in the package.json's main entry? Is it possible to rename it or place it in another folder?

Copied from original issue: projectkudu/AzureFunctionsPortal#868

[paulbatum]

From @cesarvarela on January 14, 2017 3:13

Especificilly I'm interested in bots as a service functions.

[paulbatum]

@mamaso Can you answer this one?

[mamaso]

@cesarvarela You can define the main entry point via a scriptFile property in function.json:
{ scriptFile: 'src/test.js', bindings: ... }

I like the idea to use the main entry point from package.json, that's less functions-specific config magic.

[cesarvarela]

Thanks! Is that documented somewhere? I guess the scripts entries are ignored too right (postInstall, preinstall, etc..)?

Regarding the functions-specific-magic, yes please! I think any node developer would expect that node.js functions somehow adhere to the package.json conventions.

[mamaso]

I'll add docs to the wiki for function.json and to schemastore.

At the moment, we don't run npm install on deployments of / changes to function code. If you run npm install from dev console (function app settings -> dev console -> cd 'functionname' -> npm install) you should see that your preinstall / postinstall scripts execute

[cesarvarela]

I would expect npm install to be ran too. Specifically because we use TypeScript and use post install to transpile.

Any suggestion on how can we manage that? (other than just pushing the transpiled js)

[mamaso]

Yep I agree, supporting npm install automatically for functions is on the backlog (#73)

We do support npm install for a package.json at the root of your function app, so if you hoisted your dependencies there it would work out of the box (in a hacky way).

You could add a custom deployment script to the root of your function app which runs npm install for each of your functions

[cesarvarela]

Looks like the scriptFile setting is being ignored, you can try it by just moving the index.js file of the basic bot template to a folder and updating the function.json accordingly.

messages: Unable to determine the primary function script. Try renaming your entry point script to 'run' (or 'index' in the case of Node), or alternatively you can specify the name of the entry point script explicitly by adding a 'scriptFile' property to your function metadata.

[fabiocav]

How timely :)

PR #1132 is just out (wrapping up a couple of remaining items) dealing with that exact issue. The problem is with script files outside of the function folder. Different file names work as expected.

[christopheranderson]

If there are still doc issues, we should open in azure/azure-functions.

[mamaso]

Closing this out, the only actionable piece here is adding package.json main to serve as a scriptFile default, but I think that would be better addressed in #73 if we implement it