feat: impl config

5 files changed, 186 insertions, 2 deletions

diff --git a/crates/sellershut/Cargo.toml b/crates/sellershut/Cargo.toml
index 1ce8f74..9ded17b 100644
--- a/crates/sellershut/Cargo.toml
+++ b/crates/sellershut/Cargo.toml
@@ -8,3 +8,11 @@ documentation.workspace = true
 homepage.workspace = true
 
 [dependencies]
+anyhow = "1.0.102"
+axum = { version = "0.8.8", features = ["macros"] }
+clap = { version = "4.6.0", features = ["derive", "env"] }
+serde = { workspace = true, features = ["derive"] }
+tokio = { version = "1.51.0", features = ["macros", "rt", "rt-multi-thread"] }
+toml = "1.1.2"
+tracing.workspace = true
+tracing-subscriber = { version = "0.3.23", features = ["env-filter"] }
diff --git a/crates/sellershut/src/config/cli.rs b/crates/sellershut/src/config/cli.rs
new file mode 100644
index 0000000..bcbf404
--- /dev/null
+++ b/crates/sellershut/src/config/cli.rs
@@ -0,0 +1,25 @@
+use std::path::PathBuf;
+
+use clap::{Parser, Subcommand};
+
+#[derive(Debug, Parser)]
+/// A federated marketplace platform
+pub struct Cli {
+    #[command(subcommand)]
+    pub command: Option<Commands>,
+    #[command(flatten)]
+    pub config: super::Config,
+}
+
+#[derive(Debug, Subcommand)]
+pub enum Commands {
+    #[command(name = "generate-config")]
+    GenerateConfig {
+        /// Directory to write the config file into
+        #[arg(long)]
+        dir: PathBuf,
+        /// Output filename
+        #[arg(long, default_value = "sellershut.toml")]
+        file_name: String,
+    },
+}
diff --git a/crates/sellershut/src/config/mod.rs b/crates/sellershut/src/config/mod.rs
new file mode 100644
index 0000000..b7a6ba3
--- /dev/null
+++ b/crates/sellershut/src/config/mod.rs
@@ -0,0 +1,67 @@
+pub mod cli;
+mod server;
+
+use anyhow::Result;
+use clap::Args;
+use serde::{Deserialize, Serialize};
+use std::path::{Path, PathBuf};
+
+#[derive(Debug, Clone, Args, Deserialize, Serialize, Default, PartialEq, Eq)]
+#[serde(default, rename_all = "kebab-case")]
+/// A federated marketplace platform
+pub struct Config {
+    /// Path to the config file to load.
+    #[arg(long, env = "HUT_CONFIG")]
+    #[serde(skip)]
+    config: Option<PathBuf>,
+    /// Server configuration.
+    #[command(flatten)]
+    server: server::ServerConfig,
+}
+impl Config {
+    pub fn load(cli: Self) -> Result<Self> {
+        let file = if let Some(path) = &cli.config {
+            read_config_file(path)?
+        } else {
+            Config::default()
+        };
+
+        Ok(file.merge(cli).with_defaults())
+    }
+
+    fn merge(self, higher: Self) -> Self {
+        Self {
+            config: higher.config.or(self.config),
+            server: self.server.merge(higher.server),
+        }
+    }
+
+    fn with_defaults(self) -> Self {
+        Self {
+            config: self.config,
+            server: self.server.with_defaults(),
+        }
+    }
+
+    fn defaults() -> Self {
+        Self {
+            config: None,
+            server: server::ServerConfig::defaults(),
+        }
+    }
+}
+
+fn read_config_file(path: &Path) -> Result<Config> {
+    let raw = std::fs::read_to_string(path)?;
+    Ok(toml::from_str(&raw)?)
+}
+
+pub fn generate_config_file(dir: &Path, file_name: &str) -> Result<PathBuf> {
+    std::fs::create_dir_all(dir)?;
+    let path = dir.join(file_name);
+
+    let contents = toml::to_string_pretty(&Config::defaults())?;
+    std::fs::write(&path, contents)?;
+
+    Ok(path)
+}
diff --git a/crates/sellershut/src/config/server.rs b/crates/sellershut/src/config/server.rs
new file mode 100644
index 0000000..08b7828
--- /dev/null
+++ b/crates/sellershut/src/config/server.rs
@@ -0,0 +1,63 @@
+use std::path::PathBuf;
+
+use clap::Parser;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Parser, Deserialize, Serialize, Default, PartialEq, Eq)]
+#[serde(default, rename_all = "kebab-case")]
+pub struct ServerConfig {
+    /// Port the application server listens on.
+    #[arg(short, long, env = "HUT_SERVER_PORT")]
+    port: Option<u16>,
+    /// Request timeout duration
+    #[arg(long, env = "HUT_SERVER_TIMEOUT_SECS")]
+    timeout_duration: Option<u64>,
+
+    /// Log level for the application server.
+    #[arg(long, env = "HUT_SERVER_LOG_LEVEL")]
+    log_level: Option<String>,
+
+    /// Directory where log files should be written.
+    #[arg(long, env = "HUT_SERVER_LOG_FILE_DIRECTORY")]
+    log_directory: Option<PathBuf>,
+}
+
+impl ServerConfig {
+    pub(super) fn merge(self, higher: Self) -> Self {
+        Self {
+            port: higher.port.or(self.port),
+            log_level: higher.log_level.or(self.log_level),
+            log_directory: higher.log_directory.or(self.log_directory),
+            timeout_duration: higher.timeout_duration.or(self.timeout_duration),
+        }
+    }
+
+    pub(super) fn with_defaults(self) -> Self {
+        Self {
+            port: Some(self.port.unwrap_or(2210)),
+            log_level: Some("info".to_string()),
+            log_directory: Some(self.log_directory.unwrap_or_else(std::env::temp_dir)),
+            timeout_duration: Some(self.timeout_duration.unwrap_or(5)),
+        }
+    }
+
+    pub(super) fn defaults() -> Self {
+        Self {
+            port: Some(2210),
+            log_level: Some(String::from("info")),
+            log_directory: Some(std::env::temp_dir()),
+            timeout_duration: Some(5),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::config::Config;
+
+    #[test]
+    fn log_temp_dir() {
+        let cfg = Config::load(Config::default()).unwrap();
+        assert_eq!(cfg.server.log_directory, Some(std::env::temp_dir()));
+    }
+}
diff --git a/crates/sellershut/src/main.rs b/crates/sellershut/src/main.rs
index e7a11a9..900d554 100644
--- a/crates/sellershut/src/main.rs
+++ b/crates/sellershut/src/main.rs
@@ -1,3 +1,24 @@
-fn main() {
-    println!("Hello, world!");
+mod config;
+
+use anyhow::Result;
+use clap::Parser;
+
+use crate::config::cli;
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    let cli = cli::Cli::parse();
+
+    match cli.command {
+        Some(cli::Commands::GenerateConfig { dir, file_name }) => {
+            let path = config::generate_config_file(&dir, &file_name)?;
+            println!("Wrote {}", path.display());
+        }
+        None => {
+            let cfg = config::Config::load(cli.config)?;
+            println!("{cfg:#?}");
+        }
+    }
+
+    Ok(())
 }