node: Allow for "WAL" mode in sqlite

This solves concurrency issues between the node and http daemon.

radicle-cli/examples/rad-config.md

@@ -26,6 +26,9 @@ $ rad config
     },
     "connect": [],
     "externalAddresses": [],
+    "db": {
+      "journalMode": "rollback"
+    },
     "tor": null,
     "network": "main",
     "log": "INFO",

radicle-httpd/src/api/v1/profile.rs

@@ -89,6 +89,7 @@ mod routes {
                   },
                   "connect": [],
                   "externalAddresses": [],
+                  "db": { "journalMode": "rollback" },
                   "tor": null,
                   "network": "main",
                   "log": "INFO",

radicle-node/src/runtime.rs

@@ -156,7 +156,7 @@ impl Runtime {
         let policy = config.policy;
 
         log::info!(target: "node", "Opening node database..");
-        let db = home.database_mut()?;
+        let db = home.database_mut()?.journal_mode(config.db.journal_mode)?;
         let mut stores: service::Stores<_> = db.clone().into();
 
         log::info!(target: "node", "Opening policy database..");

radicle/src/node/config.rs

@@ -7,7 +7,7 @@ use localtime::LocalDuration;
 
 use crate::node;
 use crate::node::policy::{Policy, Scope};
-use crate::node::{Address, Alias, NodeId};
+use crate::node::{db, Address, Alias, NodeId};
 
 /// Target number of peers to maintain connections to.
 pub const TARGET_OUTBOUND_PEERS: usize = 8;
@@ -260,6 +260,14 @@ pub enum TorConfig {
     Transparent,
 }
 
+/// Database configuration.
+#[derive(Debug, Default, Clone, serde::Serialize, serde::Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct DbConfig {
+    #[serde(default)]
+    pub journal_mode: db::JournalMode,
+}
+
 /// Service configuration.
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 #[serde(rename_all = "camelCase")]
@@ -279,6 +287,9 @@ pub struct Config {
     /// Specify the node's public addresses
     #[serde(default)]
     pub external_addresses: Vec<Address>,
+    /// Database config.
+    #[serde(default)]
+    pub db: DbConfig,
     /// Tor configuration.
     #[serde(default)]
     pub tor: Option<TorConfig>,
@@ -321,6 +332,7 @@ impl Config {
             listen: vec![],
             connect: HashSet::default(),
             external_addresses: vec![],
+            db: DbConfig::default(),
             network: Network::default(),
             tor: None,
             relay: Relay::default(),

radicle/src/node/db.rs

@@ -40,6 +40,19 @@ pub enum Error {
     NoRows,
 }
 
+/// Database journal mode.
+#[derive(Debug, Default, Copy, Clone, serde::Serialize, serde::Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub enum JournalMode {
+    /// "WAL" mode. Good for concurrent reads & writes, but keeps some extra files around.
+    #[serde(rename = "wal")]
+    WriteAheadLog,
+    /// Default "rollback" mode. Certain writes may block reads.
+    #[serde(alias = "rollback")]
+    #[default]
+    Rollback,
+}
+
 /// A file-backed database storing information about the network.
 #[derive(Clone)]
 pub struct Database {
@@ -93,6 +106,19 @@ impl Database {
         Ok(Self { db: Arc::new(db) })
     }
 
+    /// Set journal mode.
+    pub fn journal_mode(self, mode: JournalMode) -> Result<Self, Error> {
+        match mode {
+            JournalMode::Rollback => {
+                self.db.execute("PRAGMA journal_mode = DELETE;")?;
+            }
+            JournalMode::WriteAheadLog => {
+                self.db.execute("PRAGMA journal_mode = WAL;")?;
+            }
+        }
+        Ok(self)
+    }
+
     /// Create a new in-memory database.
     pub fn memory() -> Result<Self, Error> {
         let db = sql::Connection::open_thread_safe(":memory:")?;