feat: get config from files, environment vars, & command line flags (#112)

Add `make_config` util function that is used to load config
files
`make_config` asks for a:
1) default config
2) a list of possible file paths where a config can be loaded
3) a prefix that this config's env vars will be labeled (eg,
   `IROH_GATEWAY_PORT=4000`, the prefix is `IROH_GATEWAY` & the field
   that you are trying to set is `port`
4) command line flag overrides

The method layers these options, starting with the default config and
ending with the command line flags.

Alos, allows using `IROH_METRICS_*` env vars to set fields in the metrics
config. Also allows for `IROH_INSTANCE_ID` to set
`metrics::Config.instance_id` & `IROH_ENV` to set
`metrics::Config.service_env` fields.

Author: ramfox

examples/src/bin/importer.rs

@@ -6,7 +6,7 @@ use clap::Parser;
 use futures::{stream::TryStreamExt, StreamExt};
 use indicatif::{ProgressBar, ProgressStyle};
 use iroh_car::CarReader;
-use iroh_rpc_client::{Client, RpcClientConfig};
+use iroh_rpc_client::{Client, Config as RpcClientConfig};
 use par_stream::prelude::*;
 
 #[derive(Parser, Debug, Clone)]

iroh-bitswap/src/metrics.rs

@@ -1,21 +1,9 @@
 use git_version::git_version;
+use iroh_metrics::config::Config as MetricsConfig;
 
-pub fn metrics_config(logger_only: bool) -> iroh_metrics::config::Config {
+pub fn metrics_config_with_compile_time_info(cfg: MetricsConfig) -> MetricsConfig {
     // compile time configuration
-    let service_name = env!("CARGO_PKG_NAME").to_string();
-    let build = git_version!().to_string();
-    let version = env!("CARGO_PKG_VERSION").to_string();
-
-    // runtime configuration
-    let instance_id = std::env::var("IROH_INSTANCE_ID")
-        .unwrap_or_else(|_| names::Generator::default().next().unwrap());
-    let service_env = std::env::var("IROH_ENV").unwrap_or_else(|_| "dev".to_string());
-    iroh_metrics::config::Config::new(
-        service_name,
-        instance_id,
-        build,
-        version,
-        service_env,
-        logger_only,
-    )
+    cfg.with_service_name(env!("CARGO_PKG_NAME").to_string())
+        .with_build(git_version!().to_string())
+        .with_version(env!("CARGO_PKG_VERSION").to_string())
 }

iroh-ctl/Cargo.toml

@@ -17,3 +17,9 @@ clap = { version = "3.1.14", features = ["derive"] }
 crossterm = "0.23.2"
 tonic = "0.7.2"
 iroh-rpc-client = { path = "../iroh-rpc-client" }
+config = "0.13.1"
+iroh-util = { path = "../iroh-util" }
+serde = { version = "1.0", features = ["derive"] }
+git-version = "0.3.5"
+iroh-metrics = { path = "../iroh-metrics" }
+prometheus-client = "0.16.0"

iroh-ctl/src/config.rs

@@ -0,0 +1,69 @@
+use config::{ConfigError, Map, Source, Value};
+use iroh_metrics::config::Config as MetricsConfig;
+use iroh_rpc_client::Config as RpcClientConfig;
+use iroh_util::insert_into_config_map;
+use serde::{Deserialize, Serialize};
+
+/// CONFIG_FILE_NAME is the name of the optional config file located in the iroh home directory
+pub const CONFIG_FILE_NAME: &str = "ctl.config.toml";
+/// ENV_PREFIX should be used along side the config field name to set a config field using
+/// environment variables
+pub const ENV_PREFIX: &str = "IROH_CTL";
+
+#[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize)]
+pub struct Config {
+    pub rpc_client: RpcClientConfig,
+    pub metrics: MetricsConfig,
+}
+
+impl Source for Config {
+    fn clone_into_box(&self) -> Box<dyn Source + Send + Sync> {
+        Box::new(self.clone())
+    }
+    fn collect(&self) -> Result<Map<String, Value>, ConfigError> {
+        let mut map: Map<String, Value> = Map::new();
+        insert_into_config_map(&mut map, "rpc_client", self.rpc_client.collect()?);
+        insert_into_config_map(&mut map, "metrics", self.metrics.collect()?);
+        Ok(map)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use config::Config as ConfigBuilder;
+
+    #[test]
+    fn test_collect() {
+        let default = Config::default();
+        let mut expect: Map<String, Value> = Map::new();
+        expect.insert(
+            "rpc_client".to_string(),
+            Value::new(None, default.rpc_client.collect().unwrap()),
+        );
+        expect.insert(
+            "metrics".to_string(),
+            Value::new(None, default.metrics.collect().unwrap()),
+        );
+        let got = default.collect().unwrap();
+
+        for key in got.keys() {
+            let left = expect.get(key).unwrap();
+            let right = got.get(key).unwrap();
+            assert_eq!(left, right);
+        }
+    }
+
+    #[test]
+    fn test_build_config_from_struct() {
+        let expect = Config::default();
+        let got: Config = ConfigBuilder::builder()
+            .add_source(expect.clone())
+            .build()
+            .unwrap()
+            .try_deserialize()
+            .unwrap();
+
+        assert_eq!(expect, got);
+    }
+}

iroh-ctl/src/lib.rs

@@ -1 +1,3 @@
+pub mod config;
+pub mod metrics;
 pub mod status;

iroh-ctl/src/main.rs

@@ -1,14 +1,36 @@
+use std::collections::HashMap;
+use std::path::PathBuf;
+
 use clap::{Parser, Subcommand};
+use iroh_ctl::metrics;
+use iroh_rpc_client::Client;
+use iroh_util::{iroh_home_path, make_config};
+use prometheus_client::registry::Registry;
 
-use iroh_ctl::status;
+use iroh_ctl::{
+    config::{Config, CONFIG_FILE_NAME, ENV_PREFIX},
+    status,
+};
 
 #[derive(Parser, Debug, Clone)]
 #[clap(author, version, about, long_about = None, propagate_version = true)]
 struct Cli {
+    #[clap(long)]
+    cfg: Option<PathBuf>,
+    #[clap(long = "no-metrics")]
+    no_metrics: bool,
     #[clap(subcommand)]
     command: Commands,
 }
 
+impl Cli {
+    fn make_overrides_map(&self) -> HashMap<String, String> {
+        let mut map = HashMap::new();
+        map.insert("metrics.debug".to_string(), self.no_metrics.to_string());
+        map
+    }
+}
+
 #[derive(Subcommand, Debug, Clone)]
 enum Commands {
     /// status checks the health of the differen processes
@@ -23,11 +45,39 @@ enum Commands {
 async fn main() -> anyhow::Result<()> {
     let cli = Cli::parse();
 
+    let sources = vec![iroh_home_path(CONFIG_FILE_NAME), cli.cfg.clone()];
+    let config = make_config(
+        // default
+        Config::default(),
+        // potential config files
+        sources,
+        // env var prefix for this config
+        ENV_PREFIX,
+        // map of present command line arguments
+        cli.make_overrides_map(),
+    )
+    .unwrap();
+
+    let metrics_config = config.metrics.clone();
+
+    // stubbing in metrics
+    let prom_registry = Registry::default();
+    // TODO: need to register prometheus metrics
+    let metrics_handle = iroh_metrics::init_with_registry(
+        metrics::metrics_config_with_compile_time_info(metrics_config),
+        prom_registry,
+    )
+    .await
+    .expect("failed to initialize metrics");
+
+    let client = Client::new(&config.rpc_client).await?;
+
     match cli.command {
         Commands::Status { watch } => {
-            crate::status::status(watch).await?;
+            crate::status::status(client, watch).await?;
         }
     };
 
+    metrics_handle.shutdown();
     Ok(())
 }

iroh-ctl/src/metrics.rs

@@ -0,0 +1,9 @@
+use git_version::git_version;
+use iroh_metrics::config::Config as MetricsConfig;
+
+pub fn metrics_config_with_compile_time_info(cfg: MetricsConfig) -> MetricsConfig {
+    // compile time configuration
+    cfg.with_service_name(env!("CARGO_PKG_NAME").to_string())
+        .with_build(git_version!().to_string())
+        .with_version(env!("CARGO_PKG_VERSION").to_string())
+}

iroh-ctl/src/status.rs

@@ -4,11 +4,9 @@ use anyhow::Result;
 use crossterm::terminal::{Clear, ClearType};
 use crossterm::{cursor, style, style::Stylize, QueueableCommand};
 use futures::StreamExt;
-use iroh_rpc_client::{Client, RpcClientConfig, ServiceStatus, StatusRow, StatusTable};
-
-pub async fn status(watch: bool) -> Result<()> {
-    let client = Client::new(&RpcClientConfig::default()).await.unwrap();
+use iroh_rpc_client::{Client, ServiceStatus, StatusRow, StatusTable};
 
+pub async fn status(client: Client, watch: bool) -> Result<()> {
     let mut stdout = stdout();
     if watch {
         let status_stream = client.watch().await;

iroh-gateway/Cargo.toml

@@ -47,6 +47,10 @@ async-recursion = "1.0.0"
 handlebars = "3"
 url = "2.2.2"
 urlencoding = "2.1.0"
+dirs = "4.0.0"
+toml = "0.5.9"
+http-serde = "1.1.0"
+config = "0.13.1"
 
 [dev-dependencies]
 axum-macros = "0.2.0" # use #[axum_macros::debug_handler] for better error messages on handlers