Rendering template fails when providing resources in relative path

[SeboRei]

Observed Behavior

Platforms: Windows 11 x64, Ubuntu 24.04

➜  apigee-go-gen render apiproxy --template apiproxy.yaml --output ./out
Error: open ./jsc/addAccessTokenCookie.js: no such file or directory

Resources are given relative to template file:

Resources:
  - Resource:
      Type: jsc
      Path: ./jsc/addAccessTokenCookie.js

Template file was generated by loading a ZIP via the CLI.
Same behavior is observed for OAS.

Steps to reproduce:

1. Load API Proxy zip bundle:

apigee-go-gen transform apiproxy-to-yaml \
--input ./bundle.zip \
--output ./apiproxy.yaml

2. Execute template render

apigee-go-gen render apiproxy --template apiproxy.yaml --output ./out

3. Observe error.

Suspected cause

Render model.go

Function "GenerateBundle" copies the rendered YAML into a temporary directory which does not contain any of the resources:

func GenerateBundle(createModelFunc func(string) (v1.Model, error), cFlags *CommonFlags, validate bool, dryRun string, debug bool) error {
	var err error

	bundleOutputFile := cFlags.OutputFile

	//create a temporary location for rendering into
	tmpDir, err := os.MkdirTemp("", "render-*")
	if err != nil {
		return errors.New(err)
	}

	// render the template to a temporary location
        // THIS PRODUCES WRONG OUTCOME
	cFlags.OutputFile = flags.String(filepath.Join(tmpDir, "model.yaml"))
	err = RenderGenericTemplate(cFlags, false)
	if err != nil {
		return errors.New(err)
	}

Debug state in Line 60:

Note the discrepancy between TemplateFile and OutputFile

Suggested solution

Render the model.yaml into the current base directory and remove it after the bundle is generated.

[micovery]

Hey @SeboRei , thanks for reporting this. While on the surface it looks like a bug, it's technically working as designed (we can always improve the design). Under the hood the "render apiproxy" command is a combination of two operations.

1. Render Template
2. Transform from YAML to API Proxy

During the "render template" step it creates a temporary directory, and renders the template into it. No other files are copied. This means that when the transform command is run, if there are any files referenced from the "Resources" section, that were not copied along, then the transform command will fail.

So, to get those files also copied along into into that temporary directory, you can use the helper functions, as you see in the example templates. See:

apigee-go-gen/examples/templates/oas3/apiproxy.yaml

Lines 76 to 85 in a9839a8

	Resources:
	- Resource:
	Type: oas
	#{{ os_writefile "./openapi.yaml" $.Values.spec_string }}
	#{{ remove_oas_extensions "./openapi.yaml" }}
	Path: ./openapi.yaml
	- Resource:
	Type: properties
	#{{ os_copyfile "./test.properties" "./resources/test.properties" }}
	Path: ./test.properties

As you suggested, rendering the template temporarily into the same/original directory might be a good way to do it.