rearrange things a bit

crates/treehouse/Cargo.toml

@@ -6,15 +6,15 @@ edition = "2021"
 [dependencies]
 anyhow = "1.0.75"
 axum = "0.6.20"
+clap = { version = "4.3.22", features = ["derive"] }
 codespan-reporting = "0.11.1"
 copy_dir = "0.1.3"
 handlebars = "4.3.7"
 pulldown-cmark = { version = "0.9.3", default-features = false }
 serde = { version = "1.0.183", features = ["derive"] }
-thiserror = "1.0.47"
-tokio = "1.32.0"
+tokio = { version = "1.32.0", features = ["full"] }
 tower-http = { version = "0.4.3", features = ["fs"] }
 tower-livereload = "0.8.0"
-treehouse-format = { workspace = true }
-watchexec = "2.3.0"
+
+treehouse-format = { workspace = true }
 

crates/treehouse/src/cli/mod.rs

@@ -0,0 +1,22 @@
+pub mod regenerate;
+
+use clap::{Args, Parser, Subcommand};
+
+#[derive(Parser)]
+pub struct ProgramArgs {
+    #[clap(subcommand)]
+    pub command: Command,
+}
+
+#[derive(Subcommand)]
+pub enum Command {
+    /// Regenerate the website.
+    Regenerate(#[clap(flatten)] RegenerateArgs),
+}
+
+#[derive(Args)]
+pub struct RegenerateArgs {
+    /// Start a web server serving the static files. Useful with `cargo watch`.
+    #[clap(short, long)]
+    pub serve: bool,
+}

crates/treehouse/src/cli/regenerate.rs

@@ -0,0 +1,87 @@
+use axum::Router;
+use codespan_reporting::{
+    diagnostic::{Diagnostic, Label, LabelStyle, Severity},
+    files::SimpleFile,
+    term::termcolor::{ColorChoice, StandardStream},
+};
+use copy_dir::copy_dir;
+use handlebars::Handlebars;
+use serde::Serialize;
+use tower_http::services::ServeDir;
+use tower_livereload::LiveReloadLayer;
+use treehouse_format::ast::Roots;
+
+use crate::html::tree::branches_to_html;
+
+#[derive(Serialize)]
+pub struct TemplateData {
+    pub tree: String,
+}
+
+pub fn regenerate() -> anyhow::Result<()> {
+    let _ = std::fs::remove_dir_all("target/site");
+    std::fs::create_dir_all("target/site")?;
+
+    copy_dir("static", "target/site/static")?;
+
+    let mut handlebars = Handlebars::new();
+    handlebars.register_template_file("template/index.hbs", "template/index.hbs")?;
+
+    let root_file = std::fs::read_to_string("content/tree/index.tree")?;
+    let parse_result = Roots::parse(&mut treehouse_format::pull::Parser {
+        input: &root_file,
+        position: 0,
+    });
+
+    match parse_result {
+        Ok(roots) => {
+            let mut tree = String::new();
+            branches_to_html(&mut tree, &roots.branches, &root_file);
+
+            let index_html = handlebars.render("template/index.hbs", &TemplateData { tree })?;
+
+            std::fs::write("target/site/index.html", index_html)?;
+        }
+        Err(error) => {
+            let writer = StandardStream::stderr(ColorChoice::Auto);
+            let config = codespan_reporting::term::Config::default();
+            let files = SimpleFile::new("index.tree", &root_file);
+            let diagnostic = Diagnostic {
+                severity: Severity::Error,
+                code: None,
+                message: error.kind.to_string(),
+                labels: vec![Label {
+                    style: LabelStyle::Primary,
+                    file_id: (),
+                    range: error.range,
+                    message: String::new(),
+                }],
+                notes: vec![],
+            };
+            codespan_reporting::term::emit(&mut writer.lock(), &config, &files, &diagnostic)?;
+        }
+    }
+
+    Ok(())
+}
+
+pub fn regenerate_or_report_error() {
+    eprintln!("regenerating");
+
+    match regenerate() {
+        Ok(_) => (),
+        Err(error) => eprintln!("error: {error:?}"),
+    }
+}
+
+pub async fn web_server() -> anyhow::Result<()> {
+    let app = Router::new().nest_service("/", ServeDir::new("target/site"));
+
+    #[cfg(debug_assertions)]
+    let app = app.layer(LiveReloadLayer::new());
+
+    eprintln!("serving on port 8080");
+    Ok(axum::Server::bind(&([0, 0, 0, 0], 8080).into())
+        .serve(app.into_make_service())
+        .await?)
+}

crates/treehouse/src/main.rs

@@ -1,95 +1,24 @@
+use clap::Parser;
+use cli::{
+    regenerate::{self, regenerate_or_report_error},
+    Command, ProgramArgs,
+};
+
+mod cli;
 mod html;
 
-use axum::Router;
-use codespan_reporting::{
-    diagnostic::{Diagnostic, Label, LabelStyle, Severity},
-    files::SimpleFile,
-    term::termcolor::{ColorChoice, StandardStream},
-};
-use copy_dir::copy_dir;
-use handlebars::Handlebars;
-use html::tree::branches_to_html;
-use serde::Serialize;
-use tower_http::services::ServeDir;
-use tower_livereload::LiveReloadLayer;
-use treehouse_format::{ast::Roots, pull::Parser};
-
-#[derive(Serialize)]
-pub struct TemplateData {
-    pub tree: String,
-}
-
-fn regenerate() -> anyhow::Result<()> {
-    let _ = std::fs::remove_dir_all("target/site");
-    std::fs::create_dir_all("target/site")?;
-
-    copy_dir("static", "target/site/static")?;
-
-    let mut handlebars = Handlebars::new();
-    handlebars.register_template_file("template/index.hbs", "template/index.hbs")?;
-
-    let root_file = std::fs::read_to_string("content/tree/root.tree")?;
-    let parse_result = Roots::parse(&mut Parser {
-        input: &root_file,
-        position: 0,
-    });
-
-    match parse_result {
-        Ok(roots) => {
-            let mut tree = String::new();
-            branches_to_html(&mut tree, &roots.branches, &root_file);
-
-            let index_html = handlebars.render("template/index.hbs", &TemplateData { tree })?;
-
-            std::fs::write("target/site/index.html", index_html)?;
-        }
-        Err(error) => {
-            let writer = StandardStream::stderr(ColorChoice::Auto);
-            let config = codespan_reporting::term::Config::default();
-            let files = SimpleFile::new("root.tree", &root_file);
-            let diagnostic = Diagnostic {
-                severity: Severity::Error,
-                code: None,
-                message: error.kind.to_string(),
-                labels: vec![Label {
-                    style: LabelStyle::Primary,
-                    file_id: (),
-                    range: error.range,
-                    message: String::new(),
-                }],
-                notes: vec![],
-            };
-            codespan_reporting::term::emit(&mut writer.lock(), &config, &files, &diagnostic)?;
-        }
-    }
-
-    Ok(())
-}
-
-fn regenerate_or_report_error() {
-    eprintln!("regenerating");
-
-    match regenerate() {
-        Ok(_) => (),
-        Err(error) => eprintln!("error: {error:?}"),
-    }
-}
-
-async fn web_server() -> anyhow::Result<()> {
-    let app = Router::new().nest_service("/", ServeDir::new("target/site"));
-
-    #[cfg(debug_assertions)]
-    let app = app.layer(LiveReloadLayer::new());
-
-    Ok(axum::Server::bind(&([0, 0, 0, 0], 8080).into())
-        .serve(app.into_make_service())
-        .await?)
-}
-
 async fn fallible_main() -> anyhow::Result<()> {
+    let args = ProgramArgs::parse();
+
+    match args.command {
+        Command::Regenerate(regenerate_args) => {
             regenerate_or_report_error();
 
-    web_server().await?;
+            if regenerate_args.serve {
+                regenerate::web_server().await?;
+            }
+        }
+    }
 
     Ok(())
 }