Allow configuring database URL through an environment variable

Author: Kobzol

collector/Cargo.toml

@@ -9,7 +9,7 @@ rust-version = "1.85.0"
 [dependencies]
 anyhow = { workspace = true }
 chrono = { workspace = true, features = ["serde"] }
-clap = { workspace = true, features = ["derive"] }
+clap = { workspace = true, features = ["derive", "env"] }
 env_logger = { workspace = true }
 hashbrown = { workspace = true }
 log = { workspace = true }

collector/src/bin/collector.rs

@@ -411,7 +411,7 @@ struct DbOption {
     /// Database output file
     // This would be better as a `PathBuf`, but it's used in various ways that
     // make that tricky without adjusting several points in the code.
-    #[arg(long, default_value = "results.db")]
+    #[arg(long, default_value = "results.db", env = "DATABASE_URL")]
     db: String,
 }