tree update!

crates/treehouse/src/cli/serve.rs

@@ -0,0 +1,86 @@
+use std::{path::PathBuf, sync::Arc};
+
+use anyhow::Context;
+use axum::{
+    extract::{RawQuery, State},
+    response::Html,
+    routing::get,
+    Router,
+};
+use log::{error, info};
+use pulldown_cmark::escape::escape_html;
+use tower_http::services::ServeDir;
+
+use crate::state::{Source, Treehouse};
+
+use super::Paths;
+
+struct SystemPages {
+    four_oh_four: String,
+    b_docs: String,
+}
+
+struct Server {
+    treehouse: Treehouse,
+    target_dir: PathBuf,
+    system_pages: SystemPages,
+}
+
+pub async fn serve(treehouse: Treehouse, paths: &Paths<'_>, port: u16) -> anyhow::Result<()> {
+    let app = Router::new()
+        .nest_service("/", ServeDir::new(paths.target_dir))
+        .route("/b", get(branch))
+        .with_state(Arc::new(Server {
+            treehouse,
+            target_dir: paths.target_dir.to_owned(),
+            system_pages: SystemPages {
+                four_oh_four: std::fs::read_to_string(paths.target_dir.join("_treehouse/404.html"))
+                    .context("cannot read 404 page")?,
+                b_docs: std::fs::read_to_string(paths.target_dir.join("_treehouse/b.html"))
+                    .context("cannot read /b documentation page")?,
+            },
+        }));
+
+    #[cfg(debug_assertions)]
+    let app = app.layer(tower_livereload::LiveReloadLayer::new());
+
+    info!("serving on port {port}");
+    Ok(axum::Server::bind(&([0, 0, 0, 0], port).into())
+        .serve(app.into_make_service())
+        .await?)
+}
+
+async fn branch(RawQuery(named_id): RawQuery, State(state): State<Arc<Server>>) -> Html<String> {
+    if let Some(named_id) = named_id {
+        if let Some(&branch_id) = state.treehouse.branches_by_named_id.get(&named_id) {
+            let branch = state.treehouse.tree.branch(branch_id);
+            if let Source::Tree { input, tree_path } = state.treehouse.source(branch.file_id) {
+                let file_path = state.target_dir.join(format!("{tree_path}.html"));
+                match std::fs::read_to_string(&file_path) {
+                    Ok(content) => {
+                        let branch_markdown_content = input[branch.content.clone()].trim();
+                        let mut per_page_metadata =
+                            String::from("<meta property=\"og:description\" content=\"");
+                        escape_html(&mut per_page_metadata, branch_markdown_content).unwrap();
+                        per_page_metadata.push_str("\">");
+
+                        const PER_PAGE_METADATA_REPLACEMENT_STRING: &str = "<!-- treehouse-ca37057a-cff5-45b3-8415-3b02dbf6c799-per-branch-metadata -->";
+                        return Html(content.replacen(
+                            PER_PAGE_METADATA_REPLACEMENT_STRING,
+                            &per_page_metadata,
+                            // Replace one under the assumption that it appears in all pages.
+                            1,
+                        ));
+                    }
+                    Err(e) => {
+                        error!("error while reading file {file_path:?}: {e:?}");
+                    }
+                }
+            }
+        }
+
+        Html(state.system_pages.four_oh_four.clone())
+    } else {
+        Html(state.system_pages.b_docs.clone())
+    }
+}