Group unique values by front matter param

support
#1

I want to display all unique keywords used in the section books and group these
by genre.

content/books/book1.md:
keywords = ["Adventure", "Climbing"]
genre = "Fiction"

content/books/book2.md:
keywords = ["Adventure", "Swimming"]
genre = "Fiction"

content/books/book3.md:
keywords = ["Biography", "War"]
genre = "Non-Fiction"

What I’m looking for:

Genre: Fiction
Keywords: Adventure, Climbing, Swimmming

Genre: Non-Fiction
Keywords: Biography, War

This will give all unique keywords:

{{range (where site.Pages "Section" "books")}}
  {{range .Keywords}}
    {{$.Scratch.Add "keyword" (slice .)}}
  {{end}}
{{end}}

{{range .Scratch.Get "keyword" | uniq}}
  {{.}}
{{end}}

But I’m not sure how to group these keywords by genre so I was thinking I might need to do something like this:

{{$.Scratch.Add "index" slice}}
{{range (where site.Pages "Section" "books")}}
  {{if .Params.genre}}
    {{$.Scratch.Add "index" (dict "genre" .Params.genre "keyword" .Keywords)}}
  {{end}}
{{end}}

This gives a map, but I’m not sure where to go from here.

#2

You could group by page param:

{{ $books := where site.Pages "Section" "books" }}
{{ range $books.GroupByParam "param_key" }}
<!-- your keyword logic here -->
#3

If I understood correctly, I should do this:

{{$books := where site.Pages "Section" "books"}}
{{range $books.GroupByParam "genre" }}
{{range .Keywords}}
{{$.Scratch.Add "keyword" (slice .)}}
{{end}}
{{end}}

This gives the following error: can't evaluate field Keywords in type hugolib.PageGroup

Also, how would I get the .Key (genre) for the keywords?

#4

Look at the link in my previous reply and see the example. You have to do additional work after the grouping.

#6

Thanks. I’ve been looking at the example you linked to as well as this thread: Get all unique taxonomies of a page, but I’m still struggling.

I’ve managed to get the .Key and all keywords, but I can’t get uniq to work correctly.

{{$books := where site.Pages "Section" "books"}}
{{range $books.GroupByParam "genre"}}
<h3>{{.Key}}</h3>
<ul>
{{range .Pages}}
  {{range .Keywords}}
    {{$.Scratch.Add "keyword" (slice .)}}
  {{end}}
  {{$.Scratch.Get "keyword" | uniq}}
{{end}}
</ul>
{{end}}

I’ve tried placing {{$.Scratch.Get "keyword" | uniq}} in different places, but can’t get it to display the unique keywords for each genre.

Using similar code to the example I linked to above, I also can’t get the correct values.

{{$books := where site.Pages "Section" "books"}}
{{$slice := slice}}
{{range $books.GroupByParam "genre"}}
  <h3>{{.Key}}</h3>
  {{range .Pages}}
    {{range $tag := .Keywords}}
      {{$slice = $slice | append $tag}}
    {{end}}
    {{range $uniqueTags := $slice | uniq}}
{{$uniqueTags}}
{{end}}  
{{end}}
{{end}}

Basically, I’ve tried two different ways to achieve the same result.

#7

Try this:

{{$books := where site.Pages "Section" "books"}}
{{range $books.GroupByParam "genre"}}
<h3>Genre: {{.Key}}</h3>
{{$keywords := slice}}
{{range .Pages}}
  {{range .Keywords}}
    {{$keywords = $keywords | append .}}
  {{end}}
{{end}}
{{$keywords = uniq $keywords}}
<p>Keywords: {{delimit $keywords ", "}}</p>
{{end}}
2 Likes
#8

That works! Many thanks for being such a helpful community member on here. :raised_hands:

1 Like