Go Instanced functions

[matzew]

Currently we have zero documentation how to create an instanced Go-lang function, on our developer guide:

• https://github.com/knative/func/blob/main/docs/function-templates/golang.md

Perhaps it would also make sense to change the default to be instanced, and than just document how to get the static handler, in case folks want that.

[matzew]

Building the func (e.g. via main) branch, I see this:

./func create --help                                         

NAME
	func create - Create a function

SYNOPSIS
	func create [-l|--language] [-t|--template] [-r|--repository]
	            [-c|--confirm]  [-v|--verbose]  [path]

DESCRIPTION
	Creates a new function project.

	  $ func create -l node

	Creates a function in the current directory '.' which is written in the
	language/runtime 'node' and handles HTTP events.

	If [path] is provided, the function is initialized at that path, creating
	the path if necessary.

	To complete this command interactively, use --confirm (-c):
	  $ func create -c

	Available Language Runtimes and Templates:
	  Language     Template
	  --------     --------
	  go           cloudevents
	  go           http
	  node         cloudevents
	  node         http
	  ...
	  some more
	  ...
	  typescript   cloudevents
	  typescript   http
	  

	To install more language runtimes and their templates see 'func repository'.


EXAMPLES
	o Create a Node.js function in the current directory (the default path) which
	  handles http events (the default template).
	  $ func create -l node

	o Create a Node.js function in the directory 'myfunc'.
	  $ func create -l node myfunc

	o Create a Go function which handles CloudEvents in ./myfunc.
	  $ func create -l go -t cloudevents myfunc
		

Usage:
  func create [flags]

Aliases:
  create, init

Flags:
  -c, --confirm             Prompt to confirm options interactively ($FUNC_CONFIRM)
  -l, --language string     Language Runtime (see help text for list) ($FUNC_LANGUAGE)
  -r, --repository string   URI to a Git repository containing the specified template ($FUNC_REPOSITORY)
  -t, --template string     Function template. (see help text for list) ($FUNC_TEMPLATE) (default "http")
  -v, --verbose             Print verbose logs ($FUNC_VERBOSE)

I do not see any statement on how to get the instanced func. Or is that not possible yet?

[lkingland]

Hi Matthias,

Thank you this is in progress. Here's a quick update on the status: We now have full support for the instanced-base method signatures across all builders, so we can transition to the Instanced template, which includes inline documentation for how they work.

To be clear, this is just a documentation issue, as the new method signatures work in tandem with the legacy "static" handlers without needing to recreate the Function.

[mwmahlberg]

My 2 cents: It would at least be convenient to have the possibility to scaffold an instanced function. I can look into that for a PR, but I guess we should first decide whether to have an additional coordinate to language and template, e.g. kind with a default being non-instanced to maintain compatibility OR wether it should simply be a different kind of template. Personally, I'd say the latter makes more sense, as it is the more flexible approach.