Improve log level user interface (#539)

* Configure env_logger manually

* Set log verbosity through config API, scope it to aquadoggo by default

* Add entry to CHANGELOG.md

CHANGELOG.md

@@ -62,6 +62,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Rework networking service [#502](https://github.com/p2panda/aquadoggo/pull/502)
 - Deduplicate peer connections when initiating replication sessions [#525](https://github.com/p2panda/aquadoggo/pull/525)
 - Improve consistency and documentation of configuration API [#528](https://github.com/p2panda/aquadoggo/pull/528)
+- Improve log level config and user interface [#539](https://github.com/p2panda/aquadoggo/pull/539)
 
 ### Fixed
 

aquadoggo_cli/src/config.rs

@@ -220,6 +220,17 @@ struct Cli {
     )]
     #[serde(skip_serializing_if = "Option::is_none")]
     relay_mode: Option<bool>,
+
+    /// Set log verbosity. Use this for learning more about how your node behaves or for debugging.
+    ///
+    /// Possible log levels are: ERROR, WARN, INFO, DEBUG, TRACE. They are scoped to "aquadoggo" by
+    /// default.
+    ///
+    /// If you want to adjust the scope for deeper inspection use a filter value, for example
+    /// "=TRACE" for logging _everything_ or "aquadoggo=INFO,libp2p=DEBUG" etc.
+    #[arg(short = 'l', long, value_name = "LEVEL")]
+    #[serde(skip_serializing_if = "Option::is_none")]
+    log_level: Option<String>,
 }
 
 /// Clap converts wildcard symbols from command line arguments (for example --supported-schema-ids
@@ -250,6 +261,7 @@ where
 /// Configuration derived from environment variables and .toml file.
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct Configuration {
+    pub log_level: String,
     pub allow_schema_ids: UncheckedAllowList,
     pub database_url: String,
     pub database_max_connections: u32,
@@ -268,6 +280,7 @@ pub struct Configuration {
 impl Default for Configuration {
     fn default() -> Self {
         Self {
+            log_level: "off".into(),
             allow_schema_ids: UncheckedAllowList::Wildcard,
             database_url: "sqlite::memory:".into(),
             database_max_connections: 32,

aquadoggo_cli/src/main.rs

@@ -5,21 +5,29 @@ mod key_pair;
 mod utils;
 
 use std::convert::TryInto;
+use std::str::FromStr;
 
 use anyhow::Context;
 use aquadoggo::{AllowList, Configuration, Node};
-use log::warn;
+use env_logger::WriteStyle;
+use log::{warn, LevelFilter};
 
 use crate::config::{load_config, print_config};
 use crate::key_pair::{generate_ephemeral_key_pair, generate_or_load_key_pair};
 
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
-    env_logger::init();
-
     // Load configuration from command line arguments, environment variables and .toml file
     let (config_file_path, config) = load_config().context("Could not load configuration")?;
 
+    // Set log verbosity based on config. By default scope it always to the "aquadoggo" module.
+    let mut builder = env_logger::Builder::new();
+    let builder = match LevelFilter::from_str(&config.log_level) {
+        Ok(log_level) => builder.filter(Some("aquadoggo"), log_level),
+        Err(_) => builder.parse_filters(&config.log_level),
+    };
+    builder.write_style(WriteStyle::Always).init();
+
     // Convert to `aquadoggo` configuration format and check for invalid inputs
     let node_config = config
         .clone()