Use not literal string as parameter to .Page.Resources.GetMatch

support
1

Hi,

I’m having some issues with getting an image resource.

This works inside a shortcode and it does print the image link and both the images

{{ $imgPage := .Site.GetPage "/img" }}
{{ with (index .Page.Params (.Get "data")) }}
    {{ $background := $imgPage.Resources.GetMatch "image/background.jpg" }}
    <pre>{{ .background.RelPermalink }}</pre>
    <img src={{ .background.RelPermalink }} alt="background image">
    {{ $resized := $background.Resize "400x" }}
    <img src={{ .resized.RelPermalink }} alt="resized image">
{{ end }}

But when I replace the literal sting “image/background.jpg” with value from a front matter like this {{ $background := $imgPage.Resources.GetMatch .pathname_of_background }}
it gives me an error “at <$background.Resize>: nil pointer evaluating resource.Resource.Resize” pointing at {{ $resized := $background.Resize “400x” }}

{{ $imgPage := .Site.GetPage "/img" }}
{{ with (index .Page.Params (.Get "data")) }}
    {{ $background := $imgPage.Resources.GetMatch .pathname_of_background }}
    <pre>{{ .background.RelPermalink }}</pre>
    <img src={{ .background.RelPermalink }} alt="background image">
    {{ $resized := $background.Resize "400x" }}
    <img src={{ .resized.RelPermalink }} alt="resized image">
{{ end }}

doing

{{ $imgPage := .Site.GetPage "/img" }}
{{ with (index .Page.Params (.Get "data")) }}
    <pre>{{ .pathname_of_background }}</pre>
    {{ $background := $imgPage.Resources.GetMatch .pathname_of_background }}
    <pre>{{ $background | jsonify }}</pre>
{{ end }}

displays

image/background.jpg
{}

I tried using printf
{{ $background := $imgPage.Resources.GetMatch (printf “%s” .pathname_of_background) }}

but I still get the same error

So is there a way to get a resource by using data from front matter instead of using a string literal?
Since this code is going in a shortcode I need it to be flexible.

2

I’m pretty sure that your examples should just work, which mans that there is “something else going” on. Maybe some whitespace? What do you see if you do “

{{ printf “%q” .pathname_of_background }}
”
3

I get the value of .pathname_of_background but in quotes
“image/background.jpg”

I even tried
{{ $background := $imgPage.Resources.GetMatch (printf “%q” .pathname_of_background) }}
just in case but i get the same error.

just in case it might help. my hugo version is
Hugo Static Site Generator v0.56.1-0AD218AF linux/amd64 BuildDate: 2019-07-28T14:51:54Z

4

OK; my best guess then is that when you do

image/background.jpg
{}

It’s not actually nil.

Try to drop the jsonify.

5

when i do this

<div><pre>{{ .pathname_of_background }}</pre></div>
{{ $background := $imgPage.Resources.GetMatch (printf "%s" .pathname_of_background) }}
<div><pre>{{ $background }}</pre></div>

I get

image/background.jpg
Resource(image: image/background.jpg)

That’s good. but when i try to get the permalink (i need to put this in src of img tag) and immediately added this on the next line

   <div><pre>{{ $background.Permalink }}</pre></div>`

I again get this error

at <$background.Permalink>: nil pointer evaluating resource.Resource.Permalink
6

OK, now I think I understand.

I suspect the problem you have is that you have “many pages”, and some of them have params with a param that matches an image.

What you need to do is:

{{ $background := $imgPage.Resources.GetMatch (printf "%s" .pathname_of_background) }}
{{ with $background }}
<div><pre>{{ .RelPermalink }}</pre></div>
{{ end }}
1 Like
7

This works.

Thanks a lot. I’ve been working on this since yesterday trying to find a way to work around it.

1 Like
8

Also note that you can do something like this:

{{ $background := $imgPage.Resources.GetMatch "foo.jpg" | default $defaultBackground }}

To fall back to a default if not found.

1 Like
9

Thanks. that is worth considering. specially when I have to do some image image processing before I add it in html