feat: move atuin-server to its own binary (#3112)

A combined binary was an early dev decision, when I thought most users
would be self hosting. It is now clear that in actual fact, most users
do not self host. So let's avoid forcing every user to have a copy of
the server literally linked in, and let's stop building server deps over
and over.

The deployment for this shouldn't change. `dist` will build a binary for
this automatically, and will also add it to the installer. The latter is
perhaps something we should explore changing too!

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## Checks
- [ ] I am happy for maintainers to push small adjustments to this PR,
to speed up the review cycle
- [ ] I have checked that there are no existing pull requests for the
same thing

2 files changed, 85 insertions, 0 deletions

diff --git a/crates/atuin-server/Cargo.toml b/crates/atuin-server/Cargo.toml
index 04bf61e7..edda2532 100644
--- a/crates/atuin-server/Cargo.toml
+++ b/crates/atuin-server/Cargo.toml
@@ -10,9 +10,19 @@ license = { workspace = true }
 homepage = { workspace = true }
 repository = { workspace = true }
 
+[lib]
+name = "atuin_server"
+path = "src/lib.rs"
+
+[[bin]]
+name = "atuin-server"
+path = "src/bin/main.rs"
+
 [dependencies]
 atuin-common = { path = "../atuin-common", version = "18.11.0" }
 atuin-server-database = { path = "../atuin-server-database", version = "18.11.0" }
+atuin-server-postgres = { path = "../atuin-server-postgres", version = "18.11.0" }
+atuin-server-sqlite = { path = "../atuin-server-sqlite", version = "18.11.0" }
 
 tracing = { workspace = true }
 time = { workspace = true }
@@ -32,3 +42,5 @@ argon2 = "0.5"
 semver = { workspace = true }
 metrics-exporter-prometheus = { version = "0.18", default-features = false }
 metrics = "0.24"
+clap = { workspace = true }
+tracing-subscriber = { workspace = true }
diff --git a/crates/atuin-server/src/bin/main.rs b/crates/atuin-server/src/bin/main.rs
new file mode 100644
index 00000000..960bdf6e
--- /dev/null
+++ b/crates/atuin-server/src/bin/main.rs
@@ -0,0 +1,73 @@
+#![forbid(unsafe_code)]
+
+use std::net::SocketAddr;
+
+use atuin_server::{Settings, example_config, launch, launch_metrics_server};
+use atuin_server_database::DbType;
+use atuin_server_postgres::Postgres;
+use atuin_server_sqlite::Sqlite;
+
+use clap::Parser;
+use eyre::{Context, Result, eyre};
+use tracing_subscriber::{EnvFilter, fmt, prelude::*};
+
+#[derive(Parser, Debug)]
+#[clap(
+    name = "atuin-server",
+    about = "Atuin sync server",
+    version,
+    infer_subcommands = true
+)]
+enum Cmd {
+    /// Start the server
+    Start {
+        /// The host address to bind
+        #[clap(long)]
+        host: Option<String>,
+
+        /// The port to bind
+        #[clap(long, short)]
+        port: Option<u16>,
+    },
+
+    /// Print server example configuration
+    DefaultConfig,
+}
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    let cmd = Cmd::parse();
+
+    tracing_subscriber::registry()
+        .with(fmt::layer())
+        .with(EnvFilter::from_default_env())
+        .init();
+
+    tracing::trace!(command = ?cmd, "server command");
+
+    match cmd {
+        Cmd::Start { host, port } => {
+            let settings = Settings::new().wrap_err("could not load server settings")?;
+            let host = host.as_ref().unwrap_or(&settings.host).clone();
+            let port = port.unwrap_or(settings.port);
+            let addr = SocketAddr::new(host.parse()?, port);
+
+            if settings.metrics.enable {
+                tokio::spawn(launch_metrics_server(
+                    settings.metrics.host.clone(),
+                    settings.metrics.port,
+                ));
+            }
+
+            match settings.db_settings.db_type() {
+                DbType::Postgres => launch::<Postgres>(settings, addr).await,
+                DbType::Sqlite => launch::<Sqlite>(settings, addr).await,
+                DbType::Unknown => Err(eyre!("db_uri must start with postgres:// or sqlite://")),
+            }
+        }
+        Cmd::DefaultConfig => {
+            println!("{}", example_config());
+            Ok(())
+        }
+    }
+}