feat(hubble): add json logging (#1927)

Adds the CLI option to set logging to json format, as well as updated
the service with the log-format parameter. Also made log-format an enum
in unionvisor to make it less error prone.

hubble/Cargo.toml

@@ -41,7 +41,7 @@ time                = { version = "0.3.30", features = ["serde"] }
 tokio               = { workspace = true, features = ["full"] }
 tonic               = { workspace = true, features = ["transport", "tls", "tls-roots", "tls-webpki-roots"] }
 tracing             = { workspace = true }
-tracing-subscriber  = { workspace = true, features = ["env-filter"] }
+tracing-subscriber  = { workspace = true, features = ["env-filter", "json", "tracing-log"] }
 unionlabs           = { workspace = true, features = ["ethabi"] }
 url                 = { version = "2.4.1", features = ["serde"] }
 valuable            = { version = "0.1.0", features = ["derive"] }

hubble/hubble.nix

@@ -78,6 +78,11 @@
           description = "RUST_LOG passed to hubble";
           example = "hubble=debug";
         };
+        log-format = mkOption {
+          type = types.enum [ "json" "plain" ];
+          default = "json";
+          example = "plain";
+        };
       };
 
       config = mkIf cfg.enable {
@@ -94,6 +99,7 @@
                 ''
                   ${pkgs.lib.getExe cfg.package}  \
                     ${datastore} \
+                    --log-format ${cfg.log-format} \
                     --metrics-addr ${cfg.metrics-addr} \
                     --indexers '${indexersJson}'
                 '';

hubble/src/cli.rs

@@ -3,6 +3,8 @@ use std::{net::SocketAddr, str::FromStr};
 use clap::Parser;
 use url::Url;
 
+use crate::logging::LogFormat;
+
 /// Hubble is state machine observer.
 #[derive(Parser, Debug)]
 #[command(author, version, about, long_about = None)]
@@ -11,17 +13,6 @@ pub struct Args {
     #[arg(short, long, env = "HUBBLE_HASURA_URL")]
     pub url: Option<Url>,
 
-    /// The admin secret used to authenticate with hasura.
-    #[arg(
-        requires("url"),
-        group = "datastore",
-        required = true,
-        short = 's',
-        long,
-        env = "HUBBLE_HASURA_ADMIN_SECRET"
-    )]
-    pub hasura_admin_secret: Option<String>,
-
     /// The database url used to connect with timescaledb.
     #[arg(
         group = "datastore",
@@ -43,6 +34,16 @@ pub struct Args {
     /// Fetch the counterparty chain ids for all clients known to hubble.
     #[arg(long)]
     pub fetch_client_chain_ids: bool,
+
+    /// The log format for Hubble.
+    #[arg(
+        global = true,
+        short = 'f',
+        long,
+        env = "HUBBLE_LOG_FORMAT",
+        default_value = "json"
+    )]
+    pub log_format: LogFormat,
 }
 
 #[derive(Clone, Debug, serde::Deserialize)]

hubble/src/logging.rs

@@ -0,0 +1,42 @@
+use std::str::FromStr;
+
+use thiserror::Error;
+use tracing_subscriber::EnvFilter;
+
+pub fn init(log_format: LogFormat) {
+    match log_format {
+        LogFormat::Plain => {
+            tracing_subscriber::fmt()
+                .with_env_filter(EnvFilter::from_default_env())
+                .init();
+        }
+        LogFormat::Json => {
+            tracing_subscriber::fmt()
+                .with_env_filter(EnvFilter::from_default_env())
+                .json()
+                .init();
+        }
+    }
+}
+
+#[derive(Debug, Copy, Clone)]
+pub enum LogFormat {
+    Plain,
+    Json,
+}
+
+#[derive(Debug, Error)]
+#[error("unknown log format {0}")]
+pub struct UnknownLogFormatError(String);
+
+impl FromStr for LogFormat {
+    type Err = UnknownLogFormatError;
+
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        match s {
+            "plain" => Ok(Self::Plain),
+            "json" => Ok(Self::Json),
+            s => Err(UnknownLogFormatError(s.to_owned())),
+        }
+    }
+}

hubble/src/main.rs

@@ -7,17 +7,16 @@ use clap::Parser;
 use sqlx::postgres::PgPoolOptions;
 use tokio::task::JoinSet;
 use tracing::{error, info, warn};
-use tracing_subscriber::{fmt, prelude::*, EnvFilter};
 
+mod chain_id_query;
 mod cli;
 mod eth;
 mod healthz;
+mod logging;
 mod metrics;
 mod postgres;
 mod tm;
 
-mod chain_id_query;
-
 #[cfg(not(target_env = "msvc"))]
 use tikv_jemallocator::Jemalloc;
 
@@ -29,10 +28,8 @@ static GLOBAL: Jemalloc = Jemalloc;
 async fn main() -> color_eyre::eyre::Result<()> {
     color_eyre::install().unwrap();
     let args = crate::cli::Args::parse();
-    tracing_subscriber::registry()
-        .with(fmt::layer())
-        .with(EnvFilter::from_default_env())
-        .init();
+
+    crate::logging::init(args.log_format);
     metrics::register_custom_metrics();
 
     let db = PgPoolOptions::new()

unionvisor/unionvisor.nix

@@ -126,7 +126,7 @@
           default = self.packages.${pkgs.system}.bundle-testnet-8;
         };
         logFormat = mkOption {
-          type = types.str;
+          type = types.enum [ "json" "plain" ];
           default = "json";
           example = "plain";
         };