User guide, LaTeX: typesetting of formulae using standard syntax

layouts/partials/scripts.html

@@ -1,13 +1,5 @@
-{{ $needKaTeX  := or .Site.Params.katex.enable .Params.math .Params.chem -}}
-{{ $needmhchem := or .Site.Params.katex.mhchem.enable .Params.chem -}}
-{{ if ge hugo.Version "0.93.0" -}}
-  {{ $needKaTeX = or $needKaTeX (.Page.Store.Get "hasKaTeX") (.Page.Store.Get "hasmhchem") -}}
-  {{ $needmhchem = or $needmhchem (.Page.Store.Get "hasmhchem") -}}
-{{ else -}}
-  {{ if or $needKaTeX $needmhchem -}}
-    {{ warnf "Outdated Hugo version %s, consider upgrading to make full use of all theme features" hugo.Version  }}
-  {{ end -}}
-{{ end -}}
+{{ $needKaTeX  := or .Params.math .Site.Params.katex.enable .Params.chem .Site.Params.chem (.Page.Store.Get "hasKaTeX") (.Page.Store.Get "hasmhchem") -}}
+{{ $needmhchem := or .Params.chem .Site.Params.katex.mhchem.enable (.Page.Store.Get "hasmhchem") -}}
 
 {{ if .Site.Params.markmap.enable -}}
 <style>
@@ -34,27 +26,8 @@
   <script src='{{ "js/deflate.js" | relURL }}'></script>
 {{ end -}}
 
-{{ if  $needKaTeX -}}
-{{/* load stylesheet and scripts for KaTeX support */ -}}
-<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.16.19/dist/katex.min.css"
-      integrity="sha512-6a/jH+OTfV56Vs9Mm+Kl7ZsXWJRM2+EV+JDrW7HLHaf4OU2+9eLkHKFbzpSSbfJ5b60m+7/tQAevrzu7NP7Q2g==" crossorigin="anonymous">
-  {{/* The loading of KaTeX is deferred to speed up page rendering */ -}}
-<script defer src="https://cdn.jsdelivr.net/npm/katex@0.16.19/dist/katex.min.js"
-        integrity="sha512-FkmlbBiAj8fgfoZ8zJ+bZQCU5pdU55irXmJzFF/mXlSvBr2x/gmyLHaRu5iSpcA5Hw6CMLCCFSjB1GmgtNL2Qg=="
-        crossorigin="anonymous">
-</script>
-  {{ if $needmhchem -}}
-  {{/* To add support for displaying chemical equations and physical units, load the mhchem extension: */ -}}
-<script defer src="https://cdn.jsdelivr.net/npm/katex@0.16.19/dist/contrib/mhchem.min.js"
-        integrity="sha512-Cl4bz7Rt9ppgcBOQa4z96q3UqAzHgBzNDm66u2+lDe0ZJQu0Fgz+6jO57E+IZqzlhGzfNBY++pg7Ue+iopaLrg=="
-        crossorigin="anonymous">
-</script>
-  {{ end -}}
-  {{/* To automatically render math in text elements, include the auto-render extension: */ -}}
-<script defer src="https://cdn.jsdelivr.net/npm/katex@0.16.19/dist/contrib/auto-render.min.js"
-       integrity="sha512-6bKDPShiPRjAcdeO8T6cedaVEi0pavPbzue/G/ZRiwVlurWZOSZ/vI9fr2lhk8IPXK7z51AZac+zBvZzgDJzDQ==" crossorigin="anonymous"
-       {{ printf "onload='renderMathInElement(%s, %s);'" (( $.Page.Site.Params.katex.html_dom_element | default "document.body" ) | safeJS ) ( printf "%s" ( $.Page.Site.Params.katex.options | jsonify )) | safeHTMLAttr }}>
-</script>
+{{ if $needKaTeX -}}
+  {{ partial "scripts/katex.html" (dict "mhchem" $needmhchem) -}}
 {{ end -}}
 
 {{ $jsBs := resources.Get "vendor/bootstrap/dist/js/bootstrap.bundle.js" -}}

layouts/partials/scripts/katex.html

@@ -0,0 +1,48 @@
+{{ $version := .Site.Params.katex.version | default "latest" -}}
+
+{{/* load stylesheet and scripts for KaTeX support */ -}}
+{{ $katex_css_url := printf "https://cdn.jsdelivr.net/npm/katex@%s/dist/katex.min.css" $version -}}
+{{ with try (resources.GetRemote $katex_css_url) -}}
+  {{ with .Err -}}
+    {{ errorf "Could not retrieve KaTeX css file from CDN. Reason: %s." . -}}
+  {{ else with.Value -}}
+    {{ $secureCSS := . | resources.Fingerprint "sha512" -}}
+<link rel="stylesheet" href="{{- $katex_css_url -}}" integrity="{{- $secureCSS.Data.Integrity -}}" crossorigin="anonymous">
+  {{ end -}}
+{{ else -}}
+  {{ errorf "Invalid KaTeX version %s, could not retrieve this version from CDN." $version -}}
+{{ end -}}
+
+{{/* The loading of KaTeX is deferred to speed up page rendering */ -}}
+{{ $katex_js_url := printf "https://cdn.jsdelivr.net/npm/katex@%s/dist/katex.min.js" $version -}}
+{{ with try (resources.GetRemote $katex_js_url) -}}
+  {{ with .Err -}}
+    {{ errorf "Could not retrieve KaTeX script from CDN. Reason: %s." . -}}
+  {{ else with.Value -}}
+    {{ $secureJS := . | resources.Fingerprint "sha512" -}}
+<script defer src="{{- .RelPermalink -}}" integrity="{{- $secureJS.Data.Integrity -}}" crossorigin="anonymous" ></script>
+  {{ end -}}
+{{ else -}}
+  {{ errorf "Invalid KaTeX version %s, could not retrieve this version from CDN." $version -}}
+{{ end -}}
+
+{{/* Add support for displaying chemical equations and physical units by loading the mhchem extension: */ -}}
+{{ if .mhchem -}}
+{{ partial "scripts/mhchem.html" (dict "version" $version) -}}
+{{ end -}}
+
+{{/* To automatically render math in text elements, include the auto-render extension: */ -}}
+
+{{ $katex_autorender_url := printf "https://cdn.jsdelivr.net/npm/katex@%s/dist/contrib/auto-render.min.js" $version -}}
+{{ with try (resources.GetRemote $katex_autorender_url) -}}
+  {{ with .Err -}}
+    {{ errorf "Could not retrieve KaTeX auto render extension from CDN. Reason: %s." . -}}
+  {{ else with .Value -}}
+    {{ $secureJS := . | resources.Fingerprint "sha512" -}}
+<script defer src="{{- .RelPermalink -}}" integrity="{{- $secureJS.Data.Integrity -}}" crossorigin="anonymous"
+{{ printf "onload='renderMathInElement(%s, %s);'" (( $.Page.Site.Params.katex.html_dom_element | default "document.body" ) | safeJS ) ( printf "%s" ( $.Page.Site.Params.katex.options | jsonify )) | safeHTMLAttr -}} >
+</script>
+  {{ end -}}
+{{ else -}}
+  {{ errorf "Invalid KaTeX version %s, could not retrieve this version from CDN." $version -}}
+{{ end -}}

layouts/partials/scripts/mhchem.html

@@ -0,0 +1,12 @@
+{{/* Add support for displaying chemical equations and physical units by loading the mhchem extension: */ -}}
+{{ $mhchem_url := printf "https://cdn.jsdelivr.net/npm/katex@%s/dist/contrib/mhchem.min.js" .version -}}
+{{ with try (resources.GetRemote $mhchem_url) -}}
+  {{ with .Err -}}
+    {{ errorf "Could not retrieve mhchem script from CDN. Reason: %s." . -}}
+  {{ else with .Value -}}
+    {{ $secureJS := . | resources.Fingerprint "sha512" -}}
+<script defer src="{{- .RelPermalink -}}" integrity="{{- $secureJS.Data.Integrity -}}" crossorigin="anonymous" ></script>
+  {{ end -}}
+{{ else -}}
+  {{ errorf "Invalid KaTeX version %s, could not retrieve this version from CDN." .version -}}
+{{ end -}}