🔧 prepare configuration

.env.example

@@ -0,0 +1,2 @@
+GH_GPT_GITHUB_TOKEN="..."
+GH_GPT_OPENAI_API_KEY="..."

.gitignore

@@ -15,5 +15,6 @@ Cargo.lock
 
 
 # Added by cargo
-
 /target
+
+.env

Cargo.toml

@@ -7,5 +7,14 @@ edition = "2021"
 
 [dependencies]
 clap = {version = "4.2.7", features = ["derive"]}
+color-eyre = "0.6.2"
+config = "0.13.3"
+dotenv = "0.15.0"
 env_logger = "0.10.0"
+lazy_static = "1.4.0"
 log = "0.4.17"
+serde = "1.0.163"
+serde_derive = "1.0.163"
+
+[profile.dev.package.backtrace]
+opt-level = 3

src/config.rs

@@ -1,14 +1,27 @@
 //! General configuration
 
-/// Configuration for the application.
-#[derive(Debug, Default)]
-pub struct Config {
-    pub api_keys: ApiKeys,
-}
+use color_eyre::eyre::Result;
+use config::Config;
+use serde_derive::Deserialize;
 
-/// Configuration for the API keys.
-#[derive(Debug, Default)]
-pub struct ApiKeys {
+/// Configuration for the application.
+#[derive(Debug, Default, Deserialize)]
+pub struct GhGptConfig {
     pub github_token: String,
     pub openai_api_key: String,
 }
+
+impl GhGptConfig {
+    /// Create a new configuration from environment variables.
+    pub fn new() -> Result<Self> {
+        CONFIG.clone().try_deserialize().map_err(|e| e.into())
+    }
+}
+
+lazy_static::lazy_static! {
+    #[derive(Debug)]
+    pub static ref CONFIG: Config = Config::builder()
+        .add_source(config::Environment::with_prefix("gh_gpt"))
+        .build()
+        .unwrap();
+}

src/labels.rs

@@ -1,13 +1,15 @@
 //! Module related to Github labels.
 
+use color_eyre::eyre::Result;
 use log::debug;
 
-use crate::config::Config;
+use crate::config::GhGptConfig;
 
 /// Labelize a Github issue.
 /// # Arguments
 /// * `cfg` - The application configuration.
 /// * `gh_issue_number` - The Github issue number.
-pub fn labelize(_cfg: &Config, gh_issue_number: u64) {
+pub fn labelize(_cfg: &GhGptConfig, gh_issue_number: u64) -> Result<()> {
     debug!("labelize: {}", gh_issue_number);
+    Ok(())
 }

src/main.rs

@@ -1,32 +1,39 @@
 #[macro_use]
 extern crate log;
 use clap::Parser;
+use color_eyre::eyre::Result;
+use dotenv::dotenv;
 use gh_gpt::cli::commands::{Cli, Commands};
-use gh_gpt::config::Config;
+use gh_gpt::config::GhGptConfig;
 use gh_gpt::labels::labelize;
 
-fn main() {
+fn main() -> Result<()> {
     // Initialize the logger.
     env_logger::init();
+
+    // Initialize the error handler.
+    color_eyre::install()?;
+
+    // Load the environment variables from the .env file.
+    dotenv()?;
+
+    // Say hello.
     info!("hello from gh-gpt 🤖 !");
 
     // Parse the command line arguments.
     let cli = Cli::parse();
 
     // Retrieve the application configuration.
-    let cfg = config();
+    let cfg = GhGptConfig::new()?;
 
-    if let Some(command) = cli.command {
-        match command {
-            Commands::Labelize { gh_issue_number } => {
-                labelize(&cfg, gh_issue_number);
-            }
+    // Execute the command.
+    match cli.command {
+        Some(command) => match command {
+            Commands::Labelize { gh_issue_number } => labelize(&cfg, gh_issue_number),
+        },
+        None => {
+            info!("nothing to do there, bye 👋");
+            Ok(())
         }
     }
 }
-
-/// Parse and return the application configuration.
-fn config() -> Config {
-    // TODO: Parse the configuration from the environment variables.
-    Config::default()
-}