feat: render wml decks with paginated card sub-documents

bin/Cargo.toml

@@ -18,6 +18,8 @@ spartan = []
 nex = []
 gemtext = ["dep:itsybitsy-gemtext"]
 wap = ["dep:itsybitsy-wap"]
+# WML 1.3 decks for WAP 1.x handsets.
+wml = ["wap", "itsybitsy-wap/wml"]
 text = ["dep:itsybitsy-text"]
 # FIGlet banners and hyphenation for the text format, both off by default.
 figlet = ["text", "itsybitsy-text/figlet"]

bin/src/proto/http.rs

@@ -139,6 +139,30 @@ pub fn serve(listener: &Listener, mut stream: TcpStream) -> Result<()> {
             }
             respond(&mut stream, 200, "OK", listener.media_type(&format), body, &headers, head_only)
         }
+        Ok(Resolution::Found(Resource::Part { parent_url, slug, page })) => {
+            match page.part(&format, &slug) {
+                Some(body) => respond(
+                    &mut stream,
+                    200,
+                    "OK",
+                    listener.media_type(&format),
+                    body,
+                    &[("Vary", "Accept")],
+                    head_only,
+                ),
+                // This format does not address that sub-document, so the parent
+                // is where the content actually is.
+                None => respond(
+                    &mut stream,
+                    301,
+                    "Moved Permanently",
+                    "text/plain; charset=utf-8",
+                    b"",
+                    &[("Location", parent_url.as_str()), ("Vary", "Accept")],
+                    head_only,
+                ),
+            }
+        }
         Ok(Resolution::Found(Resource::Raw { path, media_type })) => {
             let meta = std::fs::metadata(&path)?;
             write_head(&mut stream, 200, "OK", media_type, meta.len(), &[])?;

bin/src/proto/nex.rs

@@ -45,7 +45,8 @@ pub fn serve(listener: &Listener, mut stream: TcpStream) -> Result<()> {
             let mut file = std::fs::File::open(&path)?;
             std::io::copy(&mut file, &mut stream)?;
         }
-        // resolve_flat never yields a redirect; it is matched for completeness.
+        // resolve_flat follows redirects and sub-documents to real content, so
+        // neither reaches here; they are matched for completeness.
         Ok(_) => stream.write_all(b"Not found\n")?,
         Err(err) => {
             log::warn!("{} nex {}: {err}", listener.name, for_log(path));

bin/src/proto/spartan.rs

@@ -58,6 +58,15 @@ pub fn serve(listener: &Listener, mut stream: TcpStream) -> Result<()> {
             }
             None => status(&mut stream, 5, "Not rendered", b""),
         },
+        Ok(Resolution::Found(Resource::Part { parent_url, slug, page })) => {
+            match page.part(format, &slug) {
+                Some(body) => {
+                    let media_type = listener.media_type(format);
+                    status(&mut stream, 2, media_type, body)
+                }
+                None => status(&mut stream, 3, &parent_url, b""),
+            }
+        }
         Ok(Resolution::Found(Resource::Raw { path, media_type })) => {
             write!(stream, "2 {media_type}\r\n")?;
             let mut file = std::fs::File::open(&path)?;

bin/src/registry.rs

@@ -21,6 +21,8 @@ pub fn build() -> Registry {
     {
         registry.insert(Arc::new(itsybitsy_wap::XhtmlMp)).expect("duplicate renderer id");
         registry.insert(Arc::new(itsybitsy_wap::Html)).expect("duplicate renderer id");
+        #[cfg(feature = "wml")]
+        registry.insert(Arc::new(itsybitsy_wap::Wml)).expect("duplicate renderer id");
     }
 
     registry

bin/tests/listeners.rs

@@ -28,6 +28,12 @@ impl Server {
         write(dir.path(), "one/img.png", "not really a png");
         write(dir.path(), "one/.itsybitsy.toml", "[defaults]\nmax_age = 120\n");
         write(dir.path(), "two/index.md", "# Two\n\nSecond site.\n");
+        write(
+            dir.path(),
+            "one/trail.md",
+            "Intro.\n\n<!-- card Weather -->\n\nCold and clear. Permit fee: $5.\n\n\
+         <!-- card Status -->\n\n- North: open\n",
+        );
 
         let text = format!(
             r#"
@@ -401,3 +407,107 @@ fn nothing_outside_the_root_is_reachable_over_any_protocol() {
     assert_eq!(server.send("spartan", b"one.test /.itsybitsy.toml 0\r\n"), "4 Not found\r\n");
     assert_eq!(server.send("nex", b"/.itsybitsy.toml\r\n"), "Not found\n");
 }
+
+// -- Sub-documents -------------------------------------------------------
+
+/// A page that paginates addresses sub-documents under its own URL. Only a
+/// format that paginates can serve them, so every other format redirects to the
+/// parent rather than substituting something else.
+#[cfg(feature = "wml")]
+mod parts {
+    use super::*;
+
+    /// Like `Server::start`, but with a listener that can serve WML.
+    fn wml_server() -> Server {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path().join("one");
+        fs::create_dir_all(&root).unwrap();
+        fs::write(root.join("index.md"), "# One\n").unwrap();
+        fs::write(
+            root.join("trail.md"),
+            "Intro.\n\n<!-- card Weather -->\n\nCold and clear. Permit fee: $5.\n\n\
+             <!-- card Status -->\n\n- North: open\n",
+        )
+        .unwrap();
+        fs::write(root.join("about.md"), "# About\n\nNo dividers here.\n").unwrap();
+        fs::write(root.join(".itsybitsy.toml"), "[defaults]\ndeck_per_card = true\n").unwrap();
+
+        let text = format!(
+            r#"
+version = 1
+
+[site.one]
+root = "{root}"
+hosts = ["one.test"]
+
+[listener.web]
+protocol = "http"
+bind = "127.0.0.1:0"
+formats = ["wml", "html"]
+default_site = "one"
+"#,
+            root = root.to_str().unwrap(),
+        );
+        let config: ServerConfig = toml::from_str(&text).unwrap();
+        let registry = Arc::new(itsybitsy::registry::build());
+        let formats: Vec<String> = ["wml", "html"].iter().map(|s| s.to_string()).collect();
+        let sites = Arc::new(SiteSet::build(&config, registry.clone(), formats).unwrap());
+
+        let bound = serve::bind(&config, registry, sites).unwrap();
+        let addrs = bound
+            .iter()
+            .map(|entry| (entry.listener.name.clone(), entry.local_addr().unwrap()))
+            .collect();
+        serve::spawn_all(bound);
+        Server { addrs, _dir: dir }
+    }
+
+    #[test]
+    fn a_wml_client_gets_the_card_itself() {
+        let server = wml_server();
+        let response =
+            server.request("web", "one.test", "/trail/weather", "Accept: text/vnd.wap.wml\r\n");
+        let (status, body) = split(&response);
+        assert_eq!(status, "HTTP/1.1 200 OK");
+        assert!(response.contains("Content-Type: text/vnd.wap.wml"), "{response}");
+        assert!(body.contains("<card id=\"card1\" title=\"Weather\">"), "{body}");
+        // WML reads a single dollar as a variable reference.
+        assert!(body.contains("Permit fee: $$5."), "{body}");
+    }
+
+    #[test]
+    fn a_browser_is_redirected_to_the_parent_page() {
+        // That URL space belongs to WML; HTML does not address it.
+        let server = wml_server();
+        let response = server.get("one.test", "/trail/weather");
+        assert_eq!(split(&response).0, "HTTP/1.1 301 Moved Permanently");
+        assert!(response.contains("Location: /trail"), "{response}");
+        assert!(response.contains("Vary: Accept"), "the redirect depends on Accept");
+    }
+
+    #[test]
+    fn an_unknown_card_redirects_even_for_a_wml_client() {
+        let server = wml_server();
+        let response =
+            server.request("web", "one.test", "/trail/nonexistent", "Accept: text/vnd.wap.wml\r\n");
+        assert_eq!(split(&response).0, "HTTP/1.1 301 Moved Permanently");
+        assert!(response.contains("Location: /trail"), "{response}");
+    }
+
+    #[test]
+    fn a_page_that_does_not_paginate_has_no_such_urls() {
+        let server = wml_server();
+        let response =
+            server.request("web", "one.test", "/about/whatever", "Accept: text/vnd.wap.wml\r\n");
+        assert_eq!(split(&response).0, "HTTP/1.1 404 Not Found");
+    }
+
+    #[test]
+    fn the_index_deck_links_out_to_each_card() {
+        let server = wml_server();
+        let response = server.request("web", "one.test", "/trail", "Accept: text/vnd.wap.wml\r\n");
+        let (_, body) = split(&response);
+        assert!(body.contains("<a href=\"/trail/weather#card1\">Weather</a>"), "{body}");
+        assert!(body.contains("<a href=\"/trail/status#card2\">Status</a>"), "{body}");
+    }
+}