Can I use ".Summary" variable in header?

support
1

I’m trying to set something up so that on index or list pages on my site, I would have the meta description tag populated with the site description as set in config.toml

<meta name="description" content="mysitedescription">

but on individual post pages I would have the tag populated with the content of the .Summary variable

<meta name="description" content=".Summary">

Getting the generic site description is easy enough, but I’m not having any joy accessing the .Summary variable from within header.html. Here’s what I’ve tried so far, with no luck:

<meta name="description" content="{{ if .Data.Pages.Summary }}{{ . }}{{else}}{{ .Site.Params.mysitedescription }}{{end}}">

Trouble is that, as with all variable access in Hugo, I’m finding the whole thing tantamount to voodoo.

For a start I’m not entirely sure whether the post .Summary variable is even available within the header section [Depending on how Hugo actually constructs pages, it may not exist yet, when the header section is being written].

And secondly it’s another one of those “How do I actually actually access this Variable anyway?” puzzlers. The only example I’ve got to go on is where it’s accessed on the Index page as part of the {{ range .Data.Pages }} loop, which is what I tried to work from above, but to no avail.

How would I [if I can] access the .Summary for a single post, within the single post page itself?

2

The important issue in this case is to know the distinction between Node and Page.

Nodes (list pages, index page) have no summary.

Something like this should work:

{{if .IsPage}}{{ .Summary }}{{else}}{{.Site.Params.description}}{{end}}
3

Thanks for taking the time to reply. Unfortunatey that didn’t work either:

Rendering error: template: theme/partials/header.html:9:40: executing "theme/partials/header.html" at <.IsPage>: IsPage is not a field of struct type *hugolib.Node

4

That was a copy-paste from my working site:

So, it works for me … Something weird is happening here, as IsPage is definitively a field on Node.

Some more context needed here, like Hugo version.

5

Is it necessary to know whether it is a page or node. Isn’t it enough to know whether .Summary exists or not. If it doesn’t exist then either it is a node or a page without a summary. Either way fall back on the site description.

{{ with .Summary }}{{ . }}{{ else }}{{ .Site.Params.description }} {{ end }}

6

That construction will give

Summary is not a field of struct type *hugolib.Node

On nodes.

7

@bjornerik thanks for that. I learn something new everyday. I would simply have expected the function to return false. That is what happens when one is used to thinking in php. I tried the code you posted and can confirm no problems with either 0.12 or 0.13dev (based on todays current codebase).

1 Like
8

Well, this is bizarre. I’ve just copy/pasted the line directly from your header.html file, just in case I’d made a typo before, and I’m still getting the same error:

ERROR: 2014/12/14 Rendering error: template: theme/partials/header.html:10:40: executing "theme/partials/header.html" at <.IsPage>: IsPage is not a field of struct type *hugolib.Node

Here is my header.html partial:

<html lang="en-ie">
{{"<!-- begin header partial //-->" | safeHtml}}
<head> 
    {{ "<!-- site title and article title [title-cased] -->" | safeHtml}}
    <title>{{ .Site.Title }} | {{ title .Title }}</title>
    {{"<!-- metatags //-->" | safeHtml}}
    <meta charset="{{ .Site.Params.mdrcharset }}">
    <meta name="author" content="{{ .Site.Params.mdrauthor }}">
    <meta name="description" content="{{if .IsPage}}{{ .Summary }}{{else}}{{.Site.Params.mdrdescription}}{{end}}">
    <meta name="copyright" content="{{ .Site.Params.mdrcopyright }}">
    <meta name="keywords" content="{{ if .Keywords }}{{ range .Keywords }}{{ . }}, {{ end }}{{else if isset .Params "tags" }}{{ range .Params.tags }}{{ . }}, {{ end }}{{end}}">
    <link rel="canonical" href="{{ .Permalink }}">
      {{ "<!-- CSS //-->" | safeHtml }}
      <link rel="stylesheet" href="{{ .Site.BaseUrl }}/css/stiobhart.css">
      {{"<!-- CDN hosted highlight.js lib //-->" | safeHtml}}
      <link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/8.4/styles/monokai.min.css">
      <script src="//cdnjs.cloudflare.com/ajax/libs/highlight.js/8.4/highlight.min.js"></script>
      <script>hljs.initHighlightingOnLoad();</script>
    {{ "<!-- RSS feed-->" | safeHtml }}
    {{ if .RSSlink }}<link href="{{ .RSSlink }}" rel="alternate" type="application/rss+xml" title="{{ .Title }}" />{{ end }}
</head>
{{"<!-- end header partial //-->" | safeHtml}}````
9

This is weirdo.

Whats the output of

hugo version

?

1 Like
10

The only difference i can see is that, judging from the structure of your repo, your header.html is in /layouts/partials, whereas mine is in /themes/mythemename/layouts/partials. Could that make any difference, I wonder?

My Hugo version is: v0.11

11

I’m pretty sure its a version issue.

Current release version is 0.12. The documentation is written for 0.12 - and my guess IsPage was introduced in 0.12.

0.13 is in development.

12

Ah. OK. Time to try an upgrade…

[UPDATE]

That did the trick. All working as expected now. Cheers for the help.

I think what happened was I originally installed Hugo from source, then later ‘updated’ via Homebrew, but forgot to fix the symbolic links so, although I thought I had the latest version installed, the ‘Hugo’ command was still linking against the earlier version binary.

1 Like