node: Add `--log-logger structured` and `--log-format json`

Optionally depend on crate `structured-logger`. Allow enabling it via
`--log-logger structured`. For future compatibility, provide
`--log-format` which currently only supports JSON.

Co-authored-by: Lorenz Leutgeb <lorenz.leutgeb@radicle.xyz>

Cargo.lock

@@ -910,7 +910,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "778e2ac28f6c47af28e4907f13ffd1e1ddbd400980a9abd7c8df189bf578a5ad"
 dependencies = [
  "libc",
- "windows-sys 0.59.0",
+ "windows-sys 0.60.2",
 ]
 
 [[package]]
@@ -1893,6 +1893,17 @@ dependencies = [
  "popol",
 ]
 
+[[package]]
+name = "io-uring"
+version = "0.7.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "046fa2d4d00aea763528b4950358d0ead425372445dc8ff86312b3c69ff7727b"
+dependencies = [
+ "bitflags 2.9.1",
+ "cfg-if",
+ "libc",
+]
+
 [[package]]
 name = "itertools"
 version = "0.14.0"
@@ -2090,6 +2101,10 @@ name = "log"
 version = "0.4.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "13dc2df351e3202783a1fe0d44375f7295ffb4049267b0f3018346dc122a1d94"
+dependencies = [
+ "serde",
+ "value-bag",
+]
 
 [[package]]
 name = "matchers"
@@ -2922,6 +2937,7 @@ dependencies = [
  "snapbox",
  "socket2",
  "sqlite",
+ "structured-logger",
  "tempfile",
  "test-log",
  "thiserror 1.0.69",
@@ -3369,6 +3385,15 @@ dependencies = [
  "syn 2.0.89",
 ]
 
+[[package]]
+name = "serde_fmt"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e1d4ddca14104cd60529e8c7f7ba71a2c8acd8f7f5cfcdc2faf97eeb7c3010a4"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "serde_json"
 version = "1.0.140"
@@ -3516,6 +3541,12 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "56199f7ddabf13fe5074ce809e7d3f42b42ae711800501b5b16ea82ad029c39d"
 
+[[package]]
+name = "slab"
+version = "0.4.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a2ae44ef20feb57a68b23d846850f861394c2e02dc425a50098ae8c90267589"
+
 [[package]]
 name = "smallvec"
 version = "1.13.2"
@@ -3671,12 +3702,103 @@ version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2b2231b7c3057d5e4ad0156fb3dc807d900806020c5ffa3ee6ff2c8c76fb8520"
 
+[[package]]
+name = "structured-logger"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f41647ab1dfedac6dccb4622ded5f3bea80ade9257a9ddcc89e36a43e1769cdf"
+dependencies = [
+ "log",
+ "parking_lot",
+ "serde",
+ "serde_json",
+ "tokio",
+]
+
 [[package]]
 name = "subtle"
 version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "81cdd64d312baedb58e21336b31bc043b77e01cc99033ce76ef539f78e965ebc"
 
+[[package]]
+name = "sval"
+version = "2.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7cc9739f56c5d0c44a5ed45473ec868af02eb896af8c05f616673a31e1d1bb09"
+
+[[package]]
+name = "sval_buffer"
+version = "2.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f39b07436a8c271b34dad5070c634d1d3d76d6776e938ee97b4a66a5e8003d0b"
+dependencies = [
+ "sval",
+ "sval_ref",
+]
+
+[[package]]
+name = "sval_dynamic"
+version = "2.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ffcb072d857431bf885580dacecf05ed987bac931230736739a79051dbf3499b"
+dependencies = [
+ "sval",
+]
+
+[[package]]
+name = "sval_fmt"
+version = "2.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3f214f427ad94a553e5ca5514c95c6be84667cbc5568cce957f03f3477d03d5c"
+dependencies = [
+ "itoa",
+ "ryu",
+ "sval",
+]
+
+[[package]]
+name = "sval_json"
+version = "2.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "389ed34b32e638dec9a99c8ac92d0aa1220d40041026b625474c2b6a4d6f4feb"
+dependencies = [
+ "itoa",
+ "ryu",
+ "sval",
+]
+
+[[package]]
+name = "sval_nested"
+version = "2.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "14bae8fcb2f24fee2c42c1f19037707f7c9a29a0cda936d2188d48a961c4bb2a"
+dependencies = [
+ "sval",
+ "sval_buffer",
+ "sval_ref",
+]
+
+[[package]]
+name = "sval_ref"
+version = "2.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2a4eaea3821d3046dcba81d4b8489421da42961889902342691fb7eab491d79e"
+dependencies = [
+ "sval",
+]
+
+[[package]]
+name = "sval_serde"
+version = "2.14.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "172dd4aa8cb3b45c8ac8f3b4111d644cd26938b0643ede8f93070812b87fb339"
+dependencies = [
+ "serde",
+ "sval",
+ "sval_nested",
+]
+
 [[package]]
 name = "syn"
 version = "1.0.109"
@@ -3882,6 +4004,22 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
 
+[[package]]
+name = "tokio"
+version = "1.47.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "89e49afdadebb872d3145a5638b59eb0691ea23e46ca484037cfab3b76b95038"
+dependencies = [
+ "backtrace",
+ "bytes",
+ "io-uring",
+ "libc",
+ "mio 1.0.4",
+ "parking_lot",
+ "pin-project-lite",
+ "slab",
+]
+
 [[package]]
 name = "toml"
 version = "0.9.5"
@@ -4234,6 +4372,42 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ba73ea9cf16a25df0c8caa16c51acb937d5712a8429db78a3ee29d5dcacd3a65"
 
+[[package]]
+name = "value-bag"
+version = "1.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "943ce29a8a743eb10d6082545d861b24f9d1b160b7d741e0f2cdf726bec909c5"
+dependencies = [
+ "value-bag-serde1",
+ "value-bag-sval2",
+]
+
+[[package]]
+name = "value-bag-serde1"
+version = "1.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35540706617d373b118d550d41f5dfe0b78a0c195dc13c6815e92e2638432306"
+dependencies = [
+ "erased-serde",
+ "serde",
+ "serde_fmt",
+]
+
+[[package]]
+name = "value-bag-sval2"
+version = "1.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fe7e140a2658cc16f7ee7a86e413e803fc8f9b5127adc8755c19f9fefa63a52"
+dependencies = [
+ "sval",
+ "sval_buffer",
+ "sval_dynamic",
+ "sval_fmt",
+ "sval_json",
+ "sval_ref",
+ "sval_serde",
+]
+
 [[package]]
 name = "vcpkg"
 version = "0.2.15"

crates/radicle-node/Cargo.toml

@@ -10,7 +10,7 @@ build = "build.rs"
 rust-version.workspace = true
 
 [features]
-default = ["systemd"]
+default = ["systemd", "structured-logger"]
 systemd = ["dep:radicle-systemd"]
 test = ["radicle/test", "radicle-crypto/test", "radicle-crypto/cyphernet", "radicle-protocol/test", "qcheck", "snapbox"]
 
@@ -44,6 +44,7 @@ serde = { workspace = true, features = ["derive"] }
 serde_json = { workspace = true, features = ["preserve_order"] }
 snapbox = { workspace = true, optional = true }
 socket2 = "0.5.7"
+structured-logger = { version = "1.0.4", optional = true }
 tempfile = { workspace = true }
 thiserror = { workspace = true }
 

crates/radicle-node/src/main.rs

@@ -32,8 +32,9 @@ Options
     --listen      <address>                         Address to listen on
     --log-level   <level>                           Set log level
                   (default: info)
-    --log-logger  (radicle | systemd)               Set logger implementation
+    --log-logger  (radicle | structured | systemd)  Set logger implementation
                   (default: radicle)
+    --log-format  json                              Set log format for logger implementation
     --version                                       Print program version
     --help                                          Print help
 "#;
@@ -41,6 +42,8 @@ Options
 #[derive(Debug, Clone)]
 enum Logger {
     Radicle,
+    #[cfg(feature = "structured-logger")]
+    Structured,
     #[cfg(all(feature = "systemd", target_os = "linux"))]
     Systemd,
 }
@@ -62,6 +65,8 @@ impl FromStr for Logger {
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         match s {
             "radicle" => Ok(Logger::Radicle),
+            #[cfg(feature = "structured-logger")]
+            "structured" => Ok(Logger::Structured),
             #[cfg(all(feature = "systemd", target_os = "linux"))]
             "systemd" => Ok(Logger::Systemd),
             _ => Err("unknown logger"),
@@ -69,9 +74,28 @@ impl FromStr for Logger {
     }
 }
 
+#[derive(Clone, Copy)]
+enum LogFormat {
+    #[cfg(feature = "structured-logger")]
+    Json,
+}
+
+impl FromStr for LogFormat {
+    type Err = &'static str;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            #[cfg(feature = "structured-logger")]
+            "json" => Ok(LogFormat::Json),
+            _ => Err("unknown log format"),
+        }
+    }
+}
+
 struct LogOptions {
     level: Option<log::Level>,
     logger: Logger,
+    format: Option<LogFormat>,
 }
 
 struct Options {
@@ -91,6 +115,7 @@ fn parse_options() -> Result<Options, lexopt::Error> {
     let mut force = false;
     let mut log_level = None;
     let mut log_logger = Logger::default();
+    let mut log_format = None;
 
     while let Some(arg) = parser.next()? {
         match arg {
@@ -120,6 +145,9 @@ fn parse_options() -> Result<Options, lexopt::Error> {
                 }
                 log_logger = parsed;
             }
+            Long("log-format") => {
+                log_format = Some(parser.value()?.parse_with(LogFormat::from_str)?);
+            }
             Long("help") | Short('h') => {
                 println!("{HELP_MSG}");
                 exit(0);
@@ -141,6 +169,7 @@ fn parse_options() -> Result<Options, lexopt::Error> {
         log: LogOptions {
             level: log_level,
             logger: log_logger,
+            format: log_format,
         },
     })
 }
@@ -232,6 +261,16 @@ fn initialize_logging(options: &LogOptions) -> Result<(), Box<dyn std::error::Er
 
     let logger: Box<dyn log::Log> = {
         match options.logger {
+            #[cfg(feature = "structured-logger")]
+            Logger::Structured => {
+                use structured_logger::{json, Builder};
+
+                let writer = match options.format.unwrap_or(LogFormat::Json) {
+                    LogFormat::Json => json::new_writer(io::stdout()),
+                };
+
+                Box::new(Builder::new().with_default_writer(writer).build())
+            }
             #[cfg(all(feature = "systemd", target_os = "linux"))]
             Logger::Systemd => {
                 use radicle_systemd::journal::*;