gaufre: better handle the marianne font subsetting

this should be easier to handle if the one doing it is not… me. Still
not that great but better than nothing!

website/.env.example

@@ -1 +1,2 @@
 PUBLIC_LASUITE_API_URL=https://integration.lasuite.numerique.gouv.fr
+PUBLIC_USE_GAUFRE_SUBSETTED_FONT=1

website/README.md

@@ -39,3 +39,20 @@ Source images are not tracked in the repo. To build images, you must:
   backgrounds in `public/api/backgrounds`. Depending on the offset passed, or the current week of
   the month, the service gets a different background. This is meant to be run in a cronjob to
   generate different backgrounds a few times a month.
+
+### La Gaufre font
+
+For the Gaufre content, we use a subset of Marianne font because we know we use just a few
+characters for our list. This shrinks the font file size noticeably!
+
+When you change the Gaufre content (the services shown), use the `npm run gaufre-glyphhanger-cmd`
+helper. It will show you the [glyphhanger](https://github.com/zachleat/glyphhanger) command you need
+to run locally to generate the new font file before pushing your changes.
+
+:warning: It will also tell you what to do to update the code accordingly, don't miss it :)
+
+If for any reason, you want the Gaufre to use a non-subsetted font, set the env var
+`PUBLIC_USE_GAUFRE_SUBSETTED_FONT` to `0` on the machine building the website.
+
+_This is not really streamlined and a bit error-prone, because Astro kinda gets in a way in that
+specific case. Any contribution on this is welcome._

website/bin/gaufre-glyphhanger-cmd.mjs

@@ -0,0 +1,43 @@
+import path from "path"
+import { execSync } from "child_process"
+import pc from "picocolors"
+import services from "../src/data/services.json" with { type: "json" }
+
+const glyphhangerIsInstalled = `glyphhanger --version`
+
+try {
+  execSync(glyphhangerIsInstalled, { encoding: "utf8", stdio: ["pipe", "pipe", "pipe"] })
+} catch (error) {
+  console.log(pc.yellow("Warning: it seems glyphhanger is not installed."))
+  console.log("Please see https://github.com/zachleat/glyphhanger for installation instructions.\n")
+}
+
+const enabledServices = services.filter((service) => service.enabled)
+
+const originalFontPath = path.join(
+  import.meta.dirname,
+  "..",
+  "public",
+  "fonts",
+  "Marianne-Regular.woff2",
+)
+const outputDir = path.join(import.meta.dirname, "..", "public", "fonts")
+
+const whitelist = [...enabledServices.map(({ name }) => name.replace(/ /g, "")), " ✕beta"].join("")
+
+console.log(`Run this command to generate the new subsetted gaufre font:`)
+console.log(`
+glyphhanger --formats=woff2 \\
+  --subset="${originalFontPath}" \\
+  --whitelist="${Array.from(whitelist).join("")}" \\
+  --output="${outputDir}"`)
+
+console.log(
+  pc.yellow(`
+Warning: after running the glyphhanger command, don't forget to:
+  - update the unicode-range of the subsetted font-family in the GaufrePage.astro component. The new unicode-range is outputed in the console when running glyphhanger.
+  - rename the newly generated \`Marianne-Regular-subset.woff2\` file to add a cachebusting number, that is superior to the one in the previous filename already existing in the folder.
+  - update the subsetted font-face src url in the GaufrePage.astro component to use the newly named filename.
+  - delete the previously existing subsetted font file in the \`public/fonts\` directory.
+  - commit and push the changes.`),
+)

website/package.json

@@ -10,6 +10,7 @@
     "dev": "astro dev",
     "start": "node ./server.mjs",
     "build-backgrounds": "node ./bin/build-services-backgrounds.mjs",
+    "gaufre-glyphhanger-cmd": "node ./bin/gaufre-font-cmd.mjs",
     "build": "astro check && npm run build-backgrounds && astro build",
     "preview": "astro preview",
     "astro": "astro"

website/public/fonts/readme.md

@@ -1,18 +0,0 @@
-We use a subset of Marianne font because we know we use just a few characters for our list. This
-shrinks the font file size noticeably!
-
-Example command to use to generate the subset with glyphhanger:
-
-```
-glyphhanger \
-  --subset="./Marianne-Regular.woff2" \
-  --formats=woff2 \
-  --whitelist="DeskLaSuiteNumériqueMessagerieTchapResanaFranceTransfertContactsGristLePadWebConférencedel'ÉtatWebinaire  "
-```
-
-## ⚠
-
-Make sure to also update the `unicode-range` on the `@font-face` CSS rule. You can get it on the
-glyphhanger command output.
-
-Assuming you have the Marianne-Regular.woff2 file (you can take it from the DSFR).

website/src/components/GaufrePage.astro

@@ -8,6 +8,8 @@
 import { Image } from "astro:assets"
 const logos = import.meta.glob<{ default: ImageMetadata }>("/src/assets/logos/*.{svg,png,jpg}")
 const { services } = Astro.props
+
+const useSubsettedFont = import.meta.env.PUBLIC_USE_GAUFRE_SUBSETTED_FONT !== "0"
 ---
 
 <!doctype html>
@@ -18,16 +20,27 @@ const { services } = Astro.props
   </head>
   <body>
     <div class="lagaufre">
+      {useSubsettedFont ? (
+        <style is:inline>
+          @font-face {
+            font-family: "La Gaufre";
+            src: url("/fonts/Marianne-Regular-subset-1.woff2") format("woff2");
+            unicode-range: U+20,U+27-29,U+44,U+46,U+47,U+50,U+52-54,U+56,U+57,U+61-66,U+68,U+69,U+6C-70,U+72-76,U+C9,U+E9,U+2715;
+            font-weight: 400;
+            font-display: swap;
+          }
+        </style>
+      ) : (
         <style is:inline>
           @font-face {
             font-family: "La Gaufre";
             src: url("/fonts/Marianne-Regular.woff2") format("woff2");
-          unicode-range: U+20, U+27, U+43, U+44, U+46, U+47, U+4E, U+50, U+52-54, U+56, U+57,
-            U+61-66, U+68, U+69, U+6C-70, U+72-76, U+A0, U+C9, U+E9, U+2715;
             font-weight: 400;
             font-display: swap;
           }
-
+        </style>
+      )}
+      <style is:inline>
         @font-face {
           font-family: "La Gaufre fallback";
           src: local("Arial");
@@ -51,8 +64,9 @@ const { services } = Astro.props
           height: 100% !important;
           width: 100% !important;
           font-size: 100% !important;
-          font-family: "La Gaufre", "La Gaufre fallback", BlinkMacSystemFont, "Segoe UI",
-            "Noto Sans", Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji" !important;
+          font-family:
+            "La Gaufre", "La Gaufre fallback", BlinkMacSystemFont, "Segoe UI", "Noto Sans",
+            Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji" !important;
           margin: 0 0 8px !important;
           border: 2px solid var(--lagaufre-border-color) !important;
           background-color: var(--lagaufre-bg-color) !important;
@@ -265,7 +279,7 @@ const { services } = Astro.props
                 logos[`/src/assets/logos/${id}.svg`] ||
                 logos[`/src/assets/logos/${id}.jpg`] ||
                 logos[`/src/assets/logos/${id}.png`]
-              const ariaLabel = `${name} ${!!beta ? '(bêta)' : ''} - nouvelle fenêtre`
+              const ariaLabel = `${name} ${!!beta ? "(bêta)" : ""} - nouvelle fenêtre`
               return (
                 <li>
                   <div class="lagaufre-service lagaufre-enlarge-link">
@@ -273,7 +287,11 @@ const { services } = Astro.props
                       {!!logo ? (
                         <Image src={logo()} width="40" height="40" alt="" loading="eager" />
                       ) : null}
-                      {!!beta ? <span class="lagaufre-service__beta" aria-hidden="true">beta</span> : null}
+                      {!!beta ? (
+                        <span class="lagaufre-service__beta" aria-hidden="true">
+                          beta
+                        </span>
+                      ) : null}
                     </div>
                     <a
                       target="_blank"