function "has" will panic when used on nested map

[cheungpat]

When using the has function to check if a key exists on a nested map, gomplate will panic:

$ cat template.yaml
hello: {{- if has (datasource "default").data "word" -}}
{{- (datasource "default").data.word -}}
{{- else -}}
bob
{{- end -}}

$ cat config.yaml
data:
  word: alice

$ gomplate -f template.yaml --datasource default=config.yaml
hello:panic: template: template:1:30: executing "template" at <"default">: wrong type for value; expected map[string]interface {}; got map[interface {}]interface {}

goroutine 1 [running]:
main.(*Gomplate).RunTemplate(0xc42022a060, 0xc420090f80, 0x80, 0x1a7ba60, 0xc42000e018)
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/gomplate.go:33 +0x271
main.renderTemplate(0xc42022a060, 0xc420090f80, 0x80, 0x16c5313, 0x1, 0x0, 0x0)
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/gomplate.go:99 +0xc1
main.processInputFiles(0x0, 0x0, 0xc420213050, 0x1, 0x1, 0xc420212fe0, 0x1, 0x1, 0xc42022a060, 0x16c5c1e, ...)
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/process.go:23 +0x12f
main.runTemplate(0x1aae800, 0x0, 0x0)
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/gomplate.go:88 +0x18f
main.newGomplateCmd.func1(0xc420019200, 0xc4201b9100, 0x0, 0x4, 0x0, 0x0)
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/main.go:68 +0x7e
github.com/hairyhenderson/gomplate/vendor/github.com/spf13/cobra.(*Command).execute(0xc420019200, 0xc4200101a0, 0x4, 0x4, 0xc420019200, 0xc4200101a0)
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/vendor/github.com/spf13/cobra/command.go:620 +0x3f8
github.com/hairyhenderson/gomplate/vendor/github.com/spf13/cobra.(*Command).ExecuteC(0xc420019200, 0x2, 0x16c54c5, 0x2)
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/vendor/github.com/spf13/cobra/command.go:699 +0x339
github.com/hairyhenderson/gomplate/vendor/github.com/spf13/cobra.(*Command).Execute(0xc420019200, 0xc4200f7f78, 0x0)
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/vendor/github.com/spf13/cobra/command.go:658 +0x2b
main.main()
	/Users/dee/gocode/src/github.com/hairyhenderson/gomplate/main.go:96 +0x46

Checking for key in top-level map works as expected:

$ cat template.yaml
hello: {{- if has (datasource "default") "word" -}}
{{- (datasource "default").word -}}
{{- else -}}
bob
{{- end -}}

$ cat config.yaml
word: alice

$ gomplate -f template.yaml --datasource default=config.yaml
hello:alice

[hairyhenderson]

Hi @cheungpat - thanks for the bug report, and sorry that you're experiencing this!

I've reproduced this, and I think I know what's going on. A possible workaround would be to re-convert it to a map[string]interface{} like this:

{{- if has ((datasource "default").data | toYAML | yaml) "word" -}}

It's a hack, but it should work for now. I'm going to see if I can figure out a proper fix for you though 😉

[hairyhenderson]

@cheungpat I've fixed this bug, and I've added numerous tests to make sure this sort of thing doesn't happen again! This'll be in the 1.7.0 release (next couple days, hopefully?), but if you want to try it out right away you can build gomplate from master after I merge the fix.

[cheungpat]

Seems fixed! Thank you for fixing it so quick! 👍

[hairyhenderson]

You're welcome 😉