Description generation

lib/Config.rakumod

@@ -2,29 +2,42 @@ use v6.e.PREVIEW;
 
 use HTML::Functional;
 use DB::BlogMeta;
+use DB::Post;
 
 unit class Config;
 
-# TODO: Support GFM admonitions
-method generate-post(Str:D $title, Str:D $content, BlogMeta:D $meta) {
-    my $head = head [
+method generate-head(Str:D $title, BlogMeta:D $meta, $description?) {
+    head [
         meta :charset<utf-8>;
         meta :name<viewport>, :content<width=device-width, initial-scale=1>;
+        meta :author :content<Nathan McCarty>;
         title "{$meta.title} — $title";
-        # TODO: Add style sheets
-        # Use Iosevka Alie as the monospace font
-        link :rel<stylesheet>,
-            :href<https://static.stranger.systems/fonts/IosevkaAlie/IosevkaAile.css>;
-        # Use open sans as the content font
+        # Add description, if one exists
+        do if $description ~~ Str:D {
+            meta :description :content($description)
+        } else {
+            []
+        }
+        # Preconnect to all our resource sources
+        link :rel<preconnect> :href<https://static.stranger.systems>;
         link :rel<preconnect> :href<https://fonts.googleapis.com>;
         link :rel<preconnect> :href<https://fonts.gstatic.com> :crossorigin;
+        # Load fonts, Iosevka Alie for code, and Open Sans for content
+        link :rel<stylesheet>,
+            :href<https://static.stranger.systems/fonts/IosevkaAlie/IosevkaAile.css>;
         link :rel<stylesheet>,
             :href<https://fonts.googleapis.com/css2?family=Open+Sans:ital,wght@0,300..800;1,300..800&display=swap>;
+        # Inline our style sheets
         style %?RESOURCES<main.css>.slurp;
         style %?RESOURCES<code.css>.slurp;
-        # TODO: Add description
         # TODO: Add header links
     ];
+}
+
+# TODO: Support GFM admonitions
+method generate-post(Post:D $post, BlogMeta:D $meta) {
+    my $content = $post.render-html;
+    my $head = self.generate-head($post.title, $meta, $post.description);
     my $body =
     body [
        div :class<post-body>, [

lib/DB.rakumod

@@ -78,9 +78,7 @@ class PostDB {
        mkdir $by-slug unless $by-slug.e;
        # Render all the posts and make symlinks
        for %!posts.kv -> $id, $post {
-           my $html =
-                $config.generate-post:
-                    $post.title, $post.render-html, $!meta;
+           my $html = $config.generate-post: $post, $!meta;
            my $id-path = $by-id.add: "$id.html";
            $id-path.spurt: $html;
            for $post.all-slugs -> $slug {

lib/DB/IdrisPost.rakumod

@@ -14,6 +14,9 @@ unit class IdrisPost does Post is json(:pretty);
 #| cheaty way
 has Bool:D $.idris is json = True;
 
+#| Override the generated description for this post
+has Str $.summary is json;
+
 #| Location of the ipkg for the package containing the post
 has IO::Path:D $.ipkg
     is required
@@ -48,6 +51,16 @@ method render-html(--> Str:D) {
     };
 }
 
+# Return our summary, if we have one, otherwise extract the first paragraph of
+# the markdown document
+method description(--> Str) {
+    if $!summary {
+        $!summary
+    } else {
+       markdown-first-paragraph $!source
+    }
+}
+
 # Run a pack command, erroring on failure
 sub pack(*@args) {
     my $pack = run 'pack', @args, :out, :err;

lib/DB/MarkdownPost.rakumod

@@ -11,6 +11,9 @@ unit class MarkdownPost does Post is json(:pretty);
 #| cheaty way
 has Bool:D $.markdown = True;
 
+#| Override the generated description for this post
+has Str $.summary;
+
 method title(--> Str:D) {
     markdown-title $!source
 }
@@ -19,3 +22,13 @@ method title(--> Str:D) {
 method render-html(--> Str:D) {
     markdown-to-html $!source
 }
+
+# Return our summary, if we have one, otherwise extract the first paragraph of
+# the markdown document
+method description(--> Str) {
+    if $!summary {
+        $!summary
+    } else {
+       markdown-first-paragraph $!source
+    }
+}

lib/DB/Post.rakumod

@@ -53,3 +53,8 @@ method all-slugs(--> Array[Str:D]) {
 
 #| Render this post to an html body
 method render-html(--> Str:D) {...}
+
+#| Get the description for this post, returning nil if there is none
+method description(--> Str) {
+    Nil
+}

lib/Pandoc.rakumod

@@ -3,13 +3,10 @@ unit module Pandoc;
 
 use JSON::Fast;
 
-#| Extract the title from a markdown document
-#|
-#| The title is the only top level header, will throw an error if there are
-#| multiple top level headers or are none
-sub markdown-title(IO::Path:D $file --> Str:D) is export {
+#| Run pandoc with the given arguments, dieing on failure
+sub pandoc(*@args --> Str:D) {
     # Call into pandoc
-    my $pandoc = run <pandoc -f gfm -t JSON>, $file, :out, :err;
+    my $pandoc = run 'pandoc', @args, :out, :err;
 
     # Collect the output
     my $output = $pandoc.out.slurp: :close;
@@ -17,6 +14,17 @@ sub markdown-title(IO::Path:D $file --> Str:D) is export {
     die "Pandoc exited with {$pandoc.exitcode}\nout: $output\nerr: $stderr"
     unless $pandoc;
 
+    $output
+}
+
+#| Extract the title from a markdown document
+#|
+#| The title is the only top level header, will throw an error if there are
+#| multiple top level headers or are none
+sub markdown-title(IO::Path:D $file --> Str:D) is export {
+    # Collect the output
+    my $output = pandoc <-f gfm -t JSON>, $file;
+
     # Parse out output from pandoc, we are making an executive decision to trust
     # pandoc here, so we won't do any error handling for pandoc's output
     my %parsed = from-json $output;
@@ -27,12 +35,8 @@ sub markdown-title(IO::Path:D $file --> Str:D) is export {
         $v ~~ Associative && $v<t> ~~ "Header"
     }
     my @headers = %parsed<blocks>.grep(&is-header).grep(*<c>[0] == 1);
-    if @headers.elems > 1 {
-        die "More than one top level header in $file";
-    };
-    if @headers.elems == 0 {
-        die "No top level headers in $file";
-    };
+    die "More than one top level header in $file" if @headers.elems > 1;
+    die "No top level headers in $file" if @headers.elems == 0;
 
     # Extract the header and process it into a string
     my @header = @headers[0]<c>[2].flat;
@@ -55,15 +59,38 @@ sub markdown-title(IO::Path:D $file --> Str:D) is export {
     return $title;
 }
 
+#| Use pandoc to extract the first paragraph of a markdown document
+sub markdown-first-paragraph(IO::Path:D $file --> Str:D) is export {
+    my $output = pandoc <-f gfm -t JSON>, $file;
+    my %parsed = from-json $output;
+    # Extract a list of paragraphs from the pandoc output
+    my sub is-para($v) {
+        $v ~~ Associative && $v<t> ~~ 'Para'
+    }
+    my @paras = %parsed<blocks>.grep(&is-para);
+    die "No paragraphs in markdown" if @paras.elems == 0;
+    my @para = @paras[0][0]<c>.flat;
+    # Proces it into a string
+    my $para = "";
+    for @para -> $component {
+        next unless $component ~~ Associative;
+        given $component<t> {
+            when "Str" {
+                $para ~= $component<c>;
+            }
+            when "Space" {
+                $para ~= " ";
+            }
+            default {
+                die "Invalid component type: $_";
+            }
+        }
+    }
+
+    $para
+}
+
 #| Use pandoc to render a markdown document to html
 sub markdown-to-html(IO::Path:D $file --> Str:D) is export {
-    # Call into pandoc
-    my $pandoc = run <pandoc -f gfm>, $file, :out, :err;
-    # Collect the output
-    my $output = $pandoc.out.slurp: :close;
-    my $stderr = $pandoc.err.slurp: :close;
-    die "Pandoc exited with {$pandoc.exitcode}\nout: $output\nerr: $stderr"
-    unless $pandoc;
-
-    $output
+    pandoc <-f gfm>, $file
 }