flash-extensions/flash-ext-vite-maven-plugin/src/main/java/dev/relism/flash/ext/vite/maven/BuildMojo.java

@@ -8,22 +8,30 @@ import org.apache.maven.plugins.annotations.LifecyclePhase;
 import org.apache.maven.plugins.annotations.Mojo;
 import org.apache.maven.plugins.annotations.Parameter;
 
+import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Set;
 import java.util.stream.Stream;
+import java.util.zip.Deflater;
+import java.util.zip.GZIPOutputStream;
 
 /**
  * Builds the Vite project and packages the result where {@code ViteExtension} serves it from in
- * production. Bound to {@code prepare-package}: tests never need Node, a packaged jar always has
+ * production, with a maximally gzipped {@code .gz} beside each text file, so the server compresses
- * its frontend.
+ * nothing. Bound to {@code prepare-package}: tests never need Node, a packaged jar always has its
+ * frontend.
  */
 @Mojo(name = "build", defaultPhase = LifecyclePhase.PREPARE_PACKAGE, threadSafe = true)
 public final class BuildMojo extends AbstractMojo {
 
+    /** Formats that are not compressed already; images and woff gain nothing from gzip. */
+    private static final Set<String> COMPRESSIBLE = Set.of("html", "js", "mjs", "css", "json", "map", "webmanifest", "txt", "xml", "svg", "ttf", "otf", "wasm");
+
     /** The Vite project. */
     @Parameter(property = "flash.vite.root", defaultValue = "${project.basedir}/web")
     File root;
@@ -61,7 +69,11 @@ public final class BuildMojo extends AbstractMojo {
             }
             Files.createDirectories(target.getParent());
             try (Stream<Path> built = Files.walk(dist)) {
-                for (Path from : built.toList()) Files.copy(from, target.resolve(dist.relativize(from).toString()));
+                for (Path from : built.toList()) {
+                    Path to = target.resolve(dist.relativize(from).toString());
+                    Files.copy(from, to);
+                    if (Files.isRegularFile(to)) gzip(to);
+                }
             }
         } catch (IOException e) {
             throw new MojoExecutionException("Cannot copy " + dist + " to " + target, e);
@@ -69,6 +81,18 @@ public final class BuildMojo extends AbstractMojo {
         getLog().info("Packaged " + dist + " as " + ViteExtension.CLASSPATH + "/");
     }
 
+    /** Only worth it from 1 KB, and only kept when it is smaller. */
+    private static void gzip(Path file) throws IOException {
+        String name = file.getFileName().toString();
+        if (!COMPRESSIBLE.contains(name.substring(name.lastIndexOf('.') + 1).toLowerCase()) || Files.size(file) < 1024) return;
+        byte[] raw = Files.readAllBytes(file);
+        ByteArrayOutputStream out = new ByteArrayOutputStream(raw.length / 2);
+        try (GZIPOutputStream zip = new GZIPOutputStream(out) {{ def.setLevel(Deflater.BEST_COMPRESSION); }}) {
+            zip.write(raw);
+        }
+        if (out.size() < raw.length) Files.write(file.resolveSibling(name + ".gz"), out.toByteArray());
+    }
+
     private static void run(Path project, List<String> command) throws MojoExecutionException {
         int exit;
         try {

flash-extensions/flash-ext-vite-maven-plugin/src/test/java/dev/relism/flash/ext/vite/maven/BuildMojoTest.java

@@ -9,6 +9,7 @@ import java.nio.file.Path;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.jupiter.api.Assumptions.assumeTrue;
 
 /** A package.json whose build script stands in for Vite's. Needs npm on the PATH. */
@@ -22,7 +23,7 @@ class BuildMojoTest {
         assumeTrue(onPath(), "npm is not on the PATH");
         Path web = Files.createDirectories(dir.resolve("web"));
         Files.writeString(web.resolve("package.json"), """
-                {"name":"t","private":true,"scripts":{"build":"node -e \\"const f=require('fs');f.mkdirSync('dist/assets',{recursive:true});f.writeFileSync('dist/index.html','built');f.writeFileSync('dist/assets/a-12345678.js','1')\\""}}
+                {"name":"t","private":true,"scripts":{"build":"node -e \\"const f=require('fs');f.mkdirSync('dist/assets',{recursive:true});f.writeFileSync('dist/index.html','built');f.writeFileSync('dist/assets/a-12345678.js','1');f.writeFileSync('dist/assets/b-12345678.js','x'.repeat(4096))\\""}}
                 """);
         Path classes = dir.resolve("classes");
         Files.createDirectories(classes.resolve("flash-vite"));
@@ -33,6 +34,9 @@ class BuildMojoTest {
         assertEquals("built", Files.readString(classes.resolve("flash-vite/index.html")));
         assertEquals("1", Files.readString(classes.resolve("flash-vite/assets/a-12345678.js")));
         assertFalse(Files.exists(classes.resolve("flash-vite/stale.js")));
+        // Big enough to gzip, and it shrinks; the 1-byte file is left alone.
+        assertTrue(Files.size(classes.resolve("flash-vite/assets/b-12345678.js.gz")) < 4096);
+        assertFalse(Files.exists(classes.resolve("flash-vite/assets/a-12345678.js.gz")));
     }
 
     @Test

flash-extensions/flash-ext-vite/docs/README.md

@@ -91,29 +91,31 @@ server: {
 
 Anywhere `Flash.DEV` is false, the build is read once at boot from `flash-vite/` on the classpath,
 whether that is a directory (`target/classes`) or a jar. A missing build fails the boot and names
-the plugin. Everything a response carries is prepared at boot, headers included, so serving
+the plugin. Compression already happened in the build, so boot only reads files and hashes the few
-allocates nothing.
+that revalidate: about 50 ms for a 500-file app. Everything a response carries is prepared at
+boot, headers included, so serving allocates nothing.
 
 `GET` and `HEAD` on `basePath/**` answer as follows. Backend routes still win, because Flash
 prefers specific routes over the wildcard.
 
 | Request | Answer |
 |---|---|
-| a built file under `assets/` | `Cache-Control: public, max-age=31536000, immutable` |
+| `basePath` itself (`/`) | `index.html`, whatever the client accepts |
+| a built file under `assets/` | `Cache-Control: public, max-age=31536000, immutable`, no `ETag` (it is never asked for again) |
 | any other built file (`index.html`, `favicon.svg`, …) | `Cache-Control: no-cache`, revalidated by `ETag` |
-| a path with no file extension (`/content/2`) | `index.html`, so the client-side router takes it |
+| no such file, and `Accept` names `text/html` (a browser navigating to `/content/2`) | `index.html`, so the client-side router takes it |
-| a path with an extension that matches no file | `404` |
+| no such file otherwise (a `fetch` to `/api/typo`, a missing script) | the app's own `404` |
 | `If-None-Match` with the current `ETag` | `304` with `ETag` and `Cache-Control`, no body |
 | `HEAD` | the `GET` headers, `Content-Length` included, no body |
 
-Text formats of 1 KB and more (html, js, css, json, svg, fonts, wasm, …) are gzipped once at boot
+A `.gz` beside a file is its gzipped form: the plugin writes one for every text file of 1 KB and
-and sent to clients whose `Accept-Encoding` allows gzip (`gzip;q=0` does not), with
+more, and it is sent to clients whose `Accept-Encoding` allows gzip (`gzip;q=0` does not), with
-`Vary: Accept-Encoding`. Images and woff are sent as they are, because they are compressed already.
+`Vary: Accept-Encoding`.
 
 Known limits:
 
-- A client-side route whose last segment has a dot (`/users/ada.lovelace`) is treated as a missing
+- A browser navigating straight to an API path that does not exist gets the app, which shows its
-  file. Keep dots out of client routes, or route them under `basePath` differently.
+  own not-found screen. Only an HTML navigation falls back, so API clients always get the 404.
 - Every file is held in memory, gzip included. That suits an app's own frontend. Large media belongs
   on a CDN or behind its own route.
 
@@ -124,7 +126,10 @@ The `build` goal is bound to `prepare-package`, so `mvn test` never needs Node,
 
 1. installs the dependencies with the lockfile pinned;
 2. runs `<pm> run build` in the project;
-3. replaces `target/classes/flash-vite/` with the project's `dist/`.
+3. replaces `target/classes/flash-vite/` with the project's `dist/`;
+4. writes a gzip `.gz` at maximum compression beside every html, js, css, json, map, svg, txt,
+   xml, webmanifest, font and wasm file of 1 KB and more, and keeps it only when it is smaller.
+   Images and woff are left alone, because they are compressed already.
 
 Missing Node or package manager, a failing install or build, or a build that leaves no
 `dist/index.html` fails the Maven build with the reason. The package manager's own output shows in

flash-extensions/flash-ext-vite/src/main/java/dev/relism/flash/ext/vite/Assets.java

@@ -1,13 +1,12 @@
 package dev.relism.flash.ext.vite;
 
+import dev.relism.flash.exceptions.HttpException;
 import dev.relism.flash.http.HttpStatus;
 import dev.relism.flash.models.PreEncodedHeader;
 import dev.relism.flash.models.Request;
 import dev.relism.flash.models.Response;
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
-import java.io.UncheckedIOException;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
@@ -22,13 +21,12 @@ import java.security.NoSuchAlgorithmException;
 import java.util.HashMap;
 import java.util.HexFormat;
 import java.util.Map;
-import java.util.Set;
 import java.util.stream.Stream;
-import java.util.zip.GZIPOutputStream;
 
 /**
  * The built frontend, read once from the classpath at boot and served from memory: every byte a
- * response carries, headers included, is prepared here, so serving allocates nothing.
+ * response carries, headers included, is prepared here, so serving allocates nothing. Compression
+ * happened at build time: a {@code .gz} beside a file is its gzipped form.
  */
 final class Assets {
 
@@ -61,9 +59,6 @@ final class Assets {
             Map.entry("otf", "font/otf"),
             Map.entry("wasm", "application/wasm"));
 
-    /** Formats that are not compressed already; the rest (images, woff) gain nothing from gzip. */
-    private static final Set<String> COMPRESSIBLE = Set.of("html", "js", "mjs", "css", "json", "map", "webmanifest", "txt", "xml", "svg", "ttf", "otf", "wasm");
-
     record Asset(byte[] raw, byte[] gzip, byte[] type, PreEncodedHeader cache, PreEncodedHeader etag, String tag) {}
 
     final Map<String, Asset> byPath;
@@ -92,7 +87,10 @@ final class Assets {
             try (Stream<Path> files = Files.walk(root)) {
                 for (Path file : files.filter(Files::isRegularFile).toList()) {
                     String relative = root.relativize(file).toString().replace('\\', '/');
-                    assets.put(prefix + "/" + relative, asset(relative, Files.readAllBytes(file)));
+                    if (relative.endsWith(".gz")) continue;
+                    Path gzip = file.resolveSibling(file.getFileName() + ".gz");
+                    assets.put(prefix + "/" + relative, asset(relative, Files.readAllBytes(file),
+                            Files.isRegularFile(gzip) ? Files.readAllBytes(gzip) : null));
                 }
             } finally {
                 if (opened != null) opened.close();
@@ -100,30 +98,35 @@ final class Assets {
         } catch (IOException | URISyntaxException e) {
             throw new IllegalStateException("Cannot read the built frontend at " + index, e);
         }
+        // The root is the app itself, whatever the client accepts.
+        Asset root = assets.get(prefix + "/index.html");
+        assets.put(prefix + "/", root);
+        if (!prefix.isEmpty()) assets.put(prefix, root);
         this.byPath = Map.copyOf(assets);
-        this.index = byPath.get(prefix + "/index.html");
+        this.index = root;
     }
 
     /**
-     * The asset at the request's path; a path with no file extension is a client-side route and
+     * The asset at the request's path. A path that is none is a client-side route when a browser
-     * gets {@code index.html}, one with an extension that matches nothing is a 404.
+     * navigates to it ({@code Accept} names HTML), so it gets {@code index.html}; for anything
+     * else, an API call or a missing script, it is the app's own 404.
      */
     void serve(Request req, Response res) {
-        String path = req.path();
+        Asset asset = byPath.get(req.path());
-        Asset asset = byPath.get(path);
         if (asset == null) {
-            if (path.lastIndexOf('.') > path.lastIndexOf('/')) {
+            String accept = req.header("Accept");
-                res.status(HttpStatus.NOT_FOUND);
+            if (accept == null || !accept.contains("text/html")) throw HttpException.notFound(req.path());
-                return;
-            }
             asset = index;
         }
-        res.header(asset.cache).header(asset.etag);
+        res.header(asset.cache);
+        if (asset.etag != null) {
+            res.header(asset.etag);
             String known = req.header("If-None-Match");
             if (known != null && known.contains(asset.tag)) {
                 res.status(HttpStatus.NOT_MODIFIED);
                 return;
             }
+        }
         res.type(asset.type);
         if (asset.gzip != null) {
             res.header(VARY);
@@ -152,24 +155,16 @@ final class Assets {
         return false;
     }
 
-    /** Vite puts every content-hashed file under {@code assets/}: those never change, the rest revalidate. */
+    /**
-    private static Asset asset(String path, byte[] raw) {
+     * Vite puts every content-hashed file under {@code assets/}: those never change, so they are
+     * cached for good and never revalidated, and need no ETag. The rest revalidate by one.
+     */
+    private static Asset asset(String path, byte[] raw, byte[] gzip) {
         String extension = path.substring(path.lastIndexOf('.') + 1).toLowerCase();
         byte[] type = TYPES.getOrDefault(extension, "application/octet-stream").getBytes(StandardCharsets.US_ASCII);
-        byte[] gzip = COMPRESSIBLE.contains(extension) && raw.length >= 1024 ? gzip(raw) : null;
+        if (path.startsWith("assets/")) return new Asset(raw, gzip, type, IMMUTABLE, null, null);
         String tag = "\"" + HexFormat.of().formatHex(sha1(raw)) + "\"";
-        return new Asset(raw, gzip != null && gzip.length < raw.length ? gzip : null, type,
+        return new Asset(raw, gzip, type, REVALIDATE, new PreEncodedHeader("ETag", tag), tag);
-                path.startsWith("assets/") ? IMMUTABLE : REVALIDATE, new PreEncodedHeader("ETag", tag), tag);
-    }
-
-    private static byte[] gzip(byte[] raw) {
-        ByteArrayOutputStream out = new ByteArrayOutputStream(raw.length / 2);
-        try (GZIPOutputStream zip = new GZIPOutputStream(out)) {
-            zip.write(raw);
-        } catch (IOException e) {
-            throw new UncheckedIOException(e);
-        }
-        return out.toByteArray();
     }
 
     private static byte[] sha1(byte[] raw) {

flash-extensions/flash-ext-vite/src/test/java/dev/relism/flash/ext/vite/AssetsTest.java

@@ -33,7 +33,7 @@ class AssetsTest {
             }
         }
         try (URLClassLoader loader = new URLClassLoader(new URL[]{jar.toUri().toURL()}, null)) {
-            assertEquals(Set.of("/index.html", "/assets/a-12345678.css"), new Assets(loader, "/").byPath.keySet());
+            assertEquals(Set.of("/", "/index.html", "/assets/a-12345678.css"), new Assets(loader, "/").byPath.keySet());
         }
     }
 

flash-extensions/flash-ext-vite/src/test/java/dev/relism/flash/ext/vite/ViteExtensionTest.java

@@ -11,20 +11,14 @@ import static org.junit.jupiter.api.Assertions.assertNull;
 class ViteExtensionTest {
 
     private static final String JS = "/assets/app-AbCd1234.js";
+    private static final String NAVIGATION = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";
 
     @RegisterExtension
-    static final FlashTest app = FlashTest.of(flash -> flash.get("/api/before", (req, res) -> "before")
+    static final FlashTest app = FlashTest.of(flash -> flash.install(new ViteExtension()));
-            .install(new ViteExtension()).get("/api/ping", (req, res) -> "pong"));
 
     @RegisterExtension
     static final FlashTest nested = FlashTest.of(flash -> flash.install(new ViteExtension().basePath("/app/")));
 
-    @Test
-    void backendRoutesWin() {
-        app.get("/api/ping").expectStatus(200).expectBody("pong");
-        app.get("/api/before").expectStatus(200).expectBody("before");
-    }
-
     @Test
     void hashedAssetsAreCachedForeverTheRestRevalidates() {
         app.get(JS).expectStatus(200)
@@ -41,17 +35,25 @@ class ViteExtensionTest {
         assertNull(app.get(JS).header("Content-Encoding"));
     }
 
+    /** A browser navigating gets the app, dots and all; a fetch or a script tag for nothing gets a 404. */
     @Test
-    void clientRoutesGetTheIndexMissingFilesA404() {
+    void onlyNavigationsFallBackToTheIndex() {
-        app.get("/content/2").expectStatus(200).expectHeader("Cache-Control", "no-cache").expectBodyContains("spa");
+        for (String route : new String[]{"/content/2", "/users/ada.lovelace"}) {
-        app.get("/assets/missing.js").expectStatus(404);
+            app.request().header("Accept", NAVIGATION).get(route).expectStatus(200).expectHeader("Cache-Control", "no-cache").expectBodyContains("spa");
+        }
+        app.request().header("Accept", "application/json").get("/api/nope").expectStatus(404);
+        app.request().header("Accept", "*/*").get("/assets/missing.js").expectStatus(404);
+        app.get("/content/2").expectStatus(404);
+        app.get("/").expectStatus(200).expectBodyContains("spa");
+        nested.get("/app").expectStatus(200).expectBodyContains("spa");
     }
 
     @Test
-    void anUnchangedAssetIsNotSentAgain() {
+    void anUnchangedFileIsNotSentAgainAHashedOneIsNeverAsked() {
-        String etag = app.get(JS).header("ETag");
+        String etag = app.get("/favicon.svg").header("ETag");
-        app.request().header("If-None-Match", etag).get(JS).expectStatus(304)
+        app.request().header("If-None-Match", etag).get("/favicon.svg").expectStatus(304)
-                .expectHeader("ETag", etag).expectHeader("Cache-Control", "public, max-age=31536000, immutable");
+                .expectHeader("ETag", etag).expectHeader("Cache-Control", "no-cache");
+        assertNull(app.get(JS).header("ETag"));
     }
 
     @Test
@@ -64,7 +66,7 @@ class ViteExtensionTest {
     @Test
     void aBasePathPrefixesEveryRoute() {
         nested.get("/app" + JS).expectStatus(200);
-        nested.get("/app/settings").expectStatus(200).expectBodyContains("spa");
+        nested.request().header("Accept", NAVIGATION).get("/app/settings").expectStatus(200).expectBodyContains("spa");
         nested.get(JS).expectStatus(404);
     }
 }