Add safe configuration commands

Cargo.lock

@@ -1573,6 +1573,7 @@ version = "0.1.0"
 dependencies = [
  "directories",
  "serde",
+ "tempfile",
  "thiserror 2.0.18",
  "toml_edit",
  "url",

README.md

@@ -305,8 +305,10 @@ listing and later approval/signing workflows. The current log is materialized
 from signed certificate requests, signed certificate imports, and signed
 revocation records, then reduced locally; it is not a mutable remote ACL blob.
 While the daemon is running, it also performs a background live-sync tick for
-known peers. The default interval is 30 seconds and can be changed in
-`config.toml` with `[sync] live_sync_enabled` and `live_sync_interval_ms`.
+known peers. The default interval is 30 seconds and can be changed with the
+validated configuration commands, for example
+`geth config set sync.live_sync_interval_ms 10000` or
+`geth config set sync.live_sync_enabled false`.
 Live-sync stores per-peer high-water cursors in local metadata so repeated ticks
 request only newer SSH certificate-flow and revocation log entries. Sync import
 preserves local metadata by rejecting conflicting records with ids that already
@@ -430,6 +432,22 @@ grants, and bearer-secret access without scraping prose.
 
 ## Local State
 
+Use `geth config path` to find the selected configuration file, `geth config
+show` to inspect either the file or the effective built-in defaults, and `geth
+config validate` before restarting a daemon after manual edits. The safe setter
+supports these dotted keys:
+
+- `iroh.relay_mode` (`default`, `staging`, `disabled`, or `custom`)
+- `iroh.relay_map`
+- `iroh.local_discovery` (`true` or `false`)
+- `sync.live_sync_enabled` (`true` or `false`)
+- `sync.live_sync_interval_ms` (at least `100`)
+
+`geth config set <key> <value>` preserves unrelated TOML and comments, validates
+the complete prospective config, and reports that the daemon must be restarted.
+Custom relay-map URL tables remain a deliberate manual TOML edit; validate them
+with `geth config validate`.
+
 If `GETH_HOME` is set, geth uses it. Otherwise it uses an OS-specific data
 directory. The bootstrap layout is:
 

crates/geth-cli/src/lib.rs

@@ -2,7 +2,7 @@ use anyhow::{Context, Result, bail};
 use base64::Engine;
 use clap::{Args, CommandFactory, FromArgMatches, Parser, Subcommand, ValueEnum};
 use clap_complete::{Shell, generate};
-use geth_config::GethPaths;
+use geth_config::{ConfigKey, GethConfig, GethPaths};
 use geth_control::{ControlRequest, ControlResponse, SyncStreamStatus};
 use geth_node::service::{ServiceInstallOptions, ServiceManager, ServiceReport};
 use std::io::{Read, Write, stdout};
@@ -422,6 +422,11 @@ pub enum Command {
         #[command(subcommand)]
         command: DaemonCommand,
     },
+    /// Inspect, validate, and safely edit daemon configuration
+    Config {
+        #[command(subcommand)]
+        command: ConfigCommand,
+    },
     /// Show daemon, storage, Iroh, and backend health
     Status,
     /// Inspect or trigger peer synchronization
@@ -526,6 +531,48 @@ pub enum GuideTopic {
     SmokeTest,
 }
 
+#[derive(Debug, Subcommand)]
+pub enum ConfigCommand {
+    /// Print the selected config.toml path
+    Path,
+    /// Print the selected config and its effective values
+    Show,
+    /// Parse and validate the complete selected config
+    Validate,
+    /// Safely update one supported setting and validate the result
+    Set {
+        #[arg(value_enum)]
+        key: ConfigKeyArg,
+        value: String,
+    },
+}
+
+#[derive(Clone, Copy, Debug, ValueEnum)]
+pub enum ConfigKeyArg {
+    #[value(name = "iroh.relay_mode")]
+    IrohRelayMode,
+    #[value(name = "iroh.relay_map")]
+    IrohRelayMap,
+    #[value(name = "iroh.local_discovery")]
+    IrohLocalDiscovery,
+    #[value(name = "sync.live_sync_enabled")]
+    SyncLiveSyncEnabled,
+    #[value(name = "sync.live_sync_interval_ms")]
+    SyncLiveSyncIntervalMs,
+}
+
+impl From<ConfigKeyArg> for ConfigKey {
+    fn from(value: ConfigKeyArg) -> Self {
+        match value {
+            ConfigKeyArg::IrohRelayMode => Self::IrohRelayMode,
+            ConfigKeyArg::IrohRelayMap => Self::IrohRelayMap,
+            ConfigKeyArg::IrohLocalDiscovery => Self::IrohLocalDiscovery,
+            ConfigKeyArg::SyncLiveSyncEnabled => Self::SyncLiveSyncEnabled,
+            ConfigKeyArg::SyncLiveSyncIntervalMs => Self::SyncLiveSyncIntervalMs,
+        }
+    }
+}
+
 #[derive(Debug, Subcommand)]
 #[command(after_long_help = DAEMON_AFTER_HELP)]
 pub enum DaemonCommand {
@@ -1541,6 +1588,8 @@ fn argument_help(path: &str, id: &str) -> Option<&'static str> {
         ("geth cas conflict resolve", "resolution") => {
             Some("Resolution: keep-local, accept-remote, keep-both, or manual")
         }
+        ("geth config set", "key") => Some("Supported dotted configuration key"),
+        ("geth config set", "value") => Some("New value for the selected setting"),
         ("geth node enroll request", "capabilities") => {
             Some("Requested RESOURCE=CAPABILITY pair; repeat to request more than one")
         }
@@ -1678,6 +1727,9 @@ async fn run_inner(cli: Cli) -> Result<()> {
         Command::Guide { topic } => {
             print_guide(topic, cli.json || cli.jsonl)?;
         }
+        Command::Config { command } => {
+            run_config_command(&paths, command, cli.json || cli.jsonl)?;
+        }
         Command::Init {
             admin_key,
             signing_key,
@@ -1840,6 +1892,124 @@ async fn run_inner(cli: Cli) -> Result<()> {
     Ok(())
 }
 
+fn run_config_command(paths: &GethPaths, command: ConfigCommand, json: bool) -> Result<()> {
+    let path = paths.config_file();
+    match command {
+        ConfigCommand::Path => {
+            if json {
+                println!(
+                    "{}",
+                    serde_json::to_string_pretty(&serde_json::json!({
+                        "type": "config-path",
+                        "path": path,
+                        "exists": path.exists(),
+                    }))?
+                );
+            } else {
+                println!("{}", path.display());
+            }
+        }
+        ConfigCommand::Show => {
+            let exists = path.exists();
+            let text = if exists {
+                std::fs::read_to_string(&path)
+                    .with_context(|| format!("read config at {}", path.display()))?
+            } else {
+                GethConfig::default_toml().to_owned()
+            };
+            let config = GethConfig::parse(&text)
+                .with_context(|| format!("validate config at {}", path.display()))?;
+            if json {
+                println!(
+                    "{}",
+                    serde_json::to_string_pretty(&serde_json::json!({
+                        "type": "config",
+                        "path": path,
+                        "source": if exists { "file" } else { "built-in-defaults" },
+                        "raw": text,
+                        "effective": config_json(&config),
+                    }))?
+                );
+            } else {
+                println!("# path: {}", path.display());
+                if !exists {
+                    println!("# source: built-in defaults (file does not exist yet)");
+                }
+                print!("{text}");
+                if !text.ends_with('\n') {
+                    println!();
+                }
+            }
+        }
+        ConfigCommand::Validate => {
+            let exists = path.exists();
+            let config = GethConfig::load(&path)
+                .with_context(|| format!("validate config at {}", path.display()))?;
+            if json {
+                println!(
+                    "{}",
+                    serde_json::to_string_pretty(&serde_json::json!({
+                        "type": "config-validation",
+                        "path": path,
+                        "valid": true,
+                        "source": if exists { "file" } else { "built-in-defaults" },
+                        "effective": config_json(&config),
+                    }))?
+                );
+            } else if exists {
+                println!("valid config: {}", path.display());
+            } else {
+                println!(
+                    "valid built-in defaults; config file does not exist yet: {}",
+                    path.display()
+                );
+            }
+        }
+        ConfigCommand::Set { key, value } => {
+            let key = ConfigKey::from(key);
+            let config = GethConfig::set(&path, key, &value)
+                .with_context(|| format!("set {} in {}", key.as_str(), path.display()))?;
+            if json {
+                println!(
+                    "{}",
+                    serde_json::to_string_pretty(&serde_json::json!({
+                        "type": "config-updated",
+                        "path": path,
+                        "key": key.as_str(),
+                        "value": value,
+                        "restart_required": true,
+                        "effective": config_json(&config),
+                    }))?
+                );
+            } else {
+                println!("updated {} in {}", key.as_str(), path.display());
+                println!("restart the daemon for the change to take effect");
+            }
+        }
+    }
+    Ok(())
+}
+
+fn config_json(config: &GethConfig) -> serde_json::Value {
+    let relay_maps = config
+        .iroh
+        .relay_maps
+        .iter()
+        .map(|(name, map)| (name.clone(), map.urls.clone()))
+        .collect::<std::collections::BTreeMap<_, _>>();
+    serde_json::json!({
+        "iroh": {
+            "relay_mode": config.iroh.relay_mode.label(),
+            "relay_maps": relay_maps,
+            "local_discovery": config.iroh.local_discovery,
+        },
+        "sync": {
+            "live_sync_enabled": config.sync.live_sync_enabled,
+            "live_sync_interval_ms": config.sync.live_sync_interval_ms,
+        },
+    })
+}
+
 async fn run_ephemeral_daemon(json: bool) -> Result<()> {
     let (home, paths, node) = create_ephemeral_node()?;
     if json {
@@ -2724,6 +2894,7 @@ fn request_for_command(command: Command) -> Result<ControlRequest> {
             },
         },
         Command::Guide { .. }
+        | Command::Config { .. }
         | Command::Init { .. }
         | Command::Daemon { .. }
         | Command::Backup { .. }
@@ -4853,6 +5024,31 @@ mod tests {
         ));
     }
 
+    #[test]
+    fn configuration_commands_parse_and_update_an_isolated_home() {
+        for command in ["path", "show", "validate"] {
+            let parsed = Cli::try_parse_from(["geth", "config", command]);
+            assert!(parsed.is_ok(), "config {command} should parse: {parsed:?}");
+        }
+        let parsed =
+            Cli::try_parse_from(["geth", "config", "set", "sync.live_sync_interval_ms", "500"]);
+        assert!(parsed.is_ok(), "config set should parse: {parsed:?}");
+
+        let home = tempfile::tempdir().expect("temporary geth home");
+        let paths = GethPaths::from_home(home.path());
+        run_config_command(
+            &paths,
+            ConfigCommand::Set {
+                key: ConfigKeyArg::SyncLiveSyncIntervalMs,
+                value: "500".to_owned(),
+            },
+            false,
+        )
+        .expect("set config");
+        let config = GethConfig::load(&paths.config_file()).expect("load config");
+        assert_eq!(config.sync.live_sync_interval_ms, 500);
+    }
+
     #[tokio::test]
     async fn ephemeral_daemon_rejects_an_explicit_persistent_home() {
         let parsed = Cli::try_parse_from([

crates/geth-config/Cargo.toml

@@ -10,4 +10,5 @@ directories.workspace = true
 serde.workspace = true
 thiserror.workspace = true
 toml_edit.workspace = true
+tempfile.workspace = true
 url.workspace = true

crates/geth-config/src/lib.rs

@@ -1,5 +1,7 @@
 use std::collections::BTreeMap;
+use std::io::Write;
 use std::path::{Path, PathBuf};
+use std::str::FromStr;
 
 pub const DEFAULT_CONFIG_TOML: &str = r#"# geth local node config
 # Remote node-to-node communication is Iroh-only.
@@ -124,6 +126,117 @@ pub enum ConfigError {
     InvalidLiveSyncEnabled(String),
     #[error("invalid sync live_sync_interval_ms value: {0}")]
     InvalidLiveSyncInterval(String),
+    #[error(
+        "unsupported config key `{0}`; supported keys: iroh.relay_mode, iroh.relay_map, iroh.local_discovery, sync.live_sync_enabled, sync.live_sync_interval_ms"
+    )]
+    UnsupportedKey(String),
+    #[error("invalid value `{value}` for {key}; expected {expected}")]
+    InvalidSetting {
+        key: &'static str,
+        value: String,
+        expected: &'static str,
+    },
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum ConfigKey {
+    IrohRelayMode,
+    IrohRelayMap,
+    IrohLocalDiscovery,
+    SyncLiveSyncEnabled,
+    SyncLiveSyncIntervalMs,
+}
+
+impl ConfigKey {
+    #[must_use]
+    pub const fn as_str(self) -> &'static str {
+        match self {
+            Self::IrohRelayMode => "iroh.relay_mode",
+            Self::IrohRelayMap => "iroh.relay_map",
+            Self::IrohLocalDiscovery => "iroh.local_discovery",
+            Self::SyncLiveSyncEnabled => "sync.live_sync_enabled",
+            Self::SyncLiveSyncIntervalMs => "sync.live_sync_interval_ms",
+        }
+    }
+
+    fn set(
+        self,
+        document: &mut toml_edit::DocumentMut,
+        raw_value: &str,
+    ) -> Result<(), ConfigError> {
+        match self {
+            Self::IrohRelayMode => {
+                if !matches!(raw_value, "default" | "staging" | "disabled" | "custom") {
+                    return Err(invalid_setting(
+                        self,
+                        raw_value,
+                        "default, staging, disabled, or custom",
+                    ));
+                }
+                document["iroh"]["relay_mode"] = toml_edit::value(raw_value);
+            }
+            Self::IrohRelayMap => {
+                if raw_value.trim().is_empty() {
+                    return Err(invalid_setting(
+                        self,
+                        raw_value,
+                        "a non-empty relay-map name",
+                    ));
+                }
+                document["iroh"]["relay_map"] = toml_edit::value(raw_value);
+            }
+            Self::IrohLocalDiscovery => {
+                document["iroh"]["local_discovery"] =
+                    toml_edit::value(parse_bool_setting(self, raw_value)?);
+            }
+            Self::SyncLiveSyncEnabled => {
+                document["sync"]["live_sync_enabled"] =
+                    toml_edit::value(parse_bool_setting(self, raw_value)?);
+            }
+            Self::SyncLiveSyncIntervalMs => {
+                let interval = raw_value
+                    .parse::<i64>()
+                    .ok()
+                    .filter(|interval| *interval >= 100)
+                    .ok_or_else(|| {
+                        invalid_setting(self, raw_value, "an integer of at least 100")
+                    })?;
+                document["sync"]["live_sync_interval_ms"] = toml_edit::value(interval);
+            }
+        }
+        Ok(())
+    }
+}
+
+impl FromStr for ConfigKey {
+    type Err = ConfigError;
+
+    fn from_str(value: &str) -> Result<Self, Self::Err> {
+        match value {
+            "iroh.relay_mode" => Ok(Self::IrohRelayMode),
+            "iroh.relay_map" => Ok(Self::IrohRelayMap),
+            "iroh.local_discovery" => Ok(Self::IrohLocalDiscovery),
+            "sync.live_sync_enabled" => Ok(Self::SyncLiveSyncEnabled),
+            "sync.live_sync_interval_ms" => Ok(Self::SyncLiveSyncIntervalMs),
+            other => Err(ConfigError::UnsupportedKey(other.to_owned())),
+        }
+    }
+}
+
+fn invalid_setting(key: ConfigKey, value: &str, expected: &'static str) -> ConfigError {
+    ConfigError::InvalidSetting {
+        key: key.as_str(),
+        value: value.to_owned(),
+        expected,
+    }
+}
+
+fn parse_bool_setting(key: ConfigKey, value: &str) -> Result<bool, ConfigError> {
+    match value {
+        "true" => Ok(true),
+        "false" => Ok(false),
+        _ => Err(invalid_setting(key, value, "true or false")),
+    }
 }
 
 #[derive(Clone, Debug, Default, PartialEq, Eq)]
@@ -169,6 +282,28 @@ impl GethConfig {
             sync,
         })
     }
+
+    pub fn set(path: &Path, key: ConfigKey, value: &str) -> Result<Self, ConfigError> {
+        let text = if path.exists() {
+            std::fs::read_to_string(path)?
+        } else {
+            Self::default_toml().to_owned()
+        };
+        let mut document = text.parse::<toml_edit::DocumentMut>()?;
+        key.set(&mut document, value)?;
+        let updated = document.to_string();
+        let config = Self::parse(&updated)?;
+
+        let parent = path.parent().unwrap_or_else(|| Path::new("."));
+        std::fs::create_dir_all(parent)?;
+        let mut temporary = tempfile::NamedTempFile::new_in(parent)?;
+        temporary.write_all(updated.as_bytes())?;
+        temporary.as_file().sync_all()?;
+        temporary
+            .persist(path)
+            .map_err(|error| ConfigError::Io(error.error))?;
+        Ok(config)
+    }
 }
 
 #[derive(Clone, Debug, PartialEq, Eq)]
@@ -467,4 +602,50 @@ mod tests {
         let error = GethConfig::parse("[iroh]\nlocal_discovery = \"yes\"\n").expect_err("error");
         assert!(matches!(error, ConfigError::InvalidLocalDiscovery(_)));
     }
+
+    #[test]
+    fn config_set_preserves_comments_and_validates_the_result() {
+        let home = tempfile::tempdir().expect("tempdir");
+        let path = home.path().join("config.toml");
+        std::fs::write(
+            &path,
+            "# operator note\n[iroh]\nrelay_mode = \"default\" # keep relays\n\n[sync]\nlive_sync_enabled = true\nlive_sync_interval_ms = 30000\n",
+        )
+        .expect("write config");
+
+        let config = GethConfig::set(&path, ConfigKey::SyncLiveSyncIntervalMs, "750")
+            .expect("update config");
+        assert_eq!(config.sync.live_sync_interval_ms, 750);
+        let updated = std::fs::read_to_string(&path).expect("read config");
+        assert!(updated.contains("# operator note"));
+        assert!(updated.contains("relay_mode = \"default\" # keep relays"));
+        assert!(updated.contains("live_sync_interval_ms = 750"));
+    }
+
+    #[test]
+    fn config_set_does_not_replace_a_valid_file_with_an_invalid_update() {
+        let home = tempfile::tempdir().expect("tempdir");
+        let path = home.path().join("config.toml");
+        let original = GethConfig::default_toml();
+        std::fs::write(&path, original).expect("write config");
+
+        let error = GethConfig::set(&path, ConfigKey::IrohRelayMode, "custom")
+            .expect_err("custom mode needs an existing map");
+        assert!(matches!(error, ConfigError::MissingRelayMapSelection));
+        assert_eq!(
+            std::fs::read_to_string(path).expect("read config"),
+            original
+        );
+    }
+
+    #[test]
+    fn config_set_creates_a_default_config_when_missing() {
+        let home = tempfile::tempdir().expect("tempdir");
+        let path = home.path().join("nested/config.toml");
+
+        let config =
+            GethConfig::set(&path, ConfigKey::IrohLocalDiscovery, "false").expect("create config");
+        assert!(!config.iroh.local_discovery);
+        assert!(path.is_file());
+    }
 }

docs/roadmap.md

@@ -67,6 +67,17 @@ For deployment-readiness work that cuts across feature areas, see
   - `[x]` A recursive CLI test fails when a future argument is added without a
     description.
 
+- `[x]` Add a safe configuration workflow.
+  Acceptance criteria:
+  - `[x]` `geth config path/show/validate` identify the selected file, expose
+    built-in defaults when it is absent, and report parse or semantic errors.
+  - `[x]` `geth config set` supports the common Iroh and live-sync settings,
+    preserves unrelated TOML and comments, and validates before replacement.
+  - `[x]` Updates use a same-directory temporary file and clearly report that a
+    daemon restart is required.
+  - `[x]` Tests cover comment preservation, invalid-update rollback, and
+    creation from defaults in an isolated temporary home.
+
 - `[x]` Document task-oriented user stories.
   Acceptance criteria:
   - `[x]` Workflows cover disposable evaluation, persistent background use,

docs/user-workflows.md

@@ -67,6 +67,27 @@ Set `RUST_LOG=geth_node=debug` when more daemon diagnostics are useful. Use
 `geth --home <dir> ...` to operate an isolated home without exporting an
 environment variable.
 
+## Inspect And Change Configuration
+
+User story: as an operator, I want to find and validate the exact configuration
+used by one geth home without guessing an OS-specific path or hand-editing
+common boolean and interval settings.
+
+```sh
+geth config path
+geth config show
+geth config set sync.live_sync_interval_ms 10000
+geth config validate
+geth daemon stop
+geth daemon start
+```
+
+`config show` reports built-in defaults when the file has not been created yet.
+`config set` preserves unrelated TOML and comments and refuses to replace the
+file if the complete prospective configuration is invalid. Success means
+`config validate` identifies the selected path as valid. Configuration is
+loaded at daemon startup, so restart the user service after changes.
+
 ## Establish An Owner Trust Root
 
 User story: as the mesh owner, I want my first node rooted in an existing SSH