chore: migrate settings for CFE upgrade

engine/src/main.rs

@@ -25,7 +25,10 @@ use clap::Parser;
 use futures::FutureExt;
 use jsonrpsee::core::client::ClientT;
 use multisig::{self, bitcoin::BtcSigning, eth::EthSigning, polkadot::PolkadotSigning};
-use std::sync::{atomic::AtomicBool, Arc};
+use std::{
+	path::PathBuf,
+	sync::{atomic::AtomicBool, Arc},
+};
 use tracing::info;
 use utilities::{
 	make_periodic_tick, metrics,
@@ -79,9 +82,12 @@ async fn ensure_cfe_version_record_up_to_date(
 async fn main() -> anyhow::Result<()> {
 	use_chainflip_account_id_encoding();
 
-	let opts = CommandLineOptions::parse();
+	let mut opts = CommandLineOptions::parse();
+	let provided_config_root = PathBuf::from(opts.config_root.clone());
 
-	migrate_settings0_9_3_to_0_10_0(opts.config_root.clone())?;
+	let used_config_root = migrate_settings0_9_3_to_0_10_0(opts.config_root.clone())?;
+	opts.config_root =
+		used_config_root.to_str().context("Invalid config-root provided")?.to_string();
 
 	let settings = Settings::new(opts).context("Error reading settings")?;
 
@@ -149,6 +155,12 @@ async fn main() -> anyhow::Result<()> {
 								task_scope(|scope| start(scope, settings, state_chain_stream, state_chain_client).boxed())
 							);
 
+							// Effectively, we want to move the files from the temp-migrated location, to the location
+							// that the user has specified they want the file to be - updating it in-place.
+							// Note: the backup was already created and is in this folder too.
+							std::fs::rename(&used_config_root, &provided_config_root)
+								.context("Unable to replace old settings with temp settings")?;
+
 							cfe_status = CfeStatus::Active(handle);
 						} else {
 							tracing::info!("Current runtime is not compatible with this CFE version ({:?})", *CFE_VERSION);

engine/src/settings.rs

@@ -335,6 +335,8 @@ where
 	deserializer.deserialize_any(PathVisitor)
 }
 
+pub const SETTINGS_IN_CONFIG_ROOT: &str = "config/Settings.toml";
+
 /// Describes behaviour required by a struct to be used for as settings/configuration
 pub trait CfSettings
 where
@@ -358,7 +360,7 @@ where
 		// If the file does not exist we will try and continue anyway.
 		// Because if all of the settings are covered in the environment, cli options and defaults,
 		// then we don't need it.
-		let settings_file = PathBuf::from(config_root.clone()).join("config/Settings.toml");
+		let settings_file = PathBuf::from(config_root.clone()).join(SETTINGS_IN_CONFIG_ROOT);
 		let file_present = settings_file.is_file();
 		if file_present {
 			builder = builder.add_source(File::from(settings_file.clone()));

engine/src/settings_migrate.rs

@@ -26,17 +26,21 @@ use toml::{map::Map, Table, Value};
 
 use anyhow::{Context, Result};
 
+use crate::settings::SETTINGS_IN_CONFIG_ROOT;
+
 const PRIVATE_KEY_FILE: &str = "private_key_file";
 const WS_NODE_ENDPOINT: &str = "ws_node_endpoint";
 const HTTP_NODE_ENDPOINT: &str = "http_node_endpoint";
 const RPC: &str = "rpc";
 
-pub fn migrate_settings0_9_3_to_0_10_0(config_root: String) -> Result<()> {
-	let settings_file = PathBuf::from(config_root).join("config/Settings.toml");
+// Returns the path to the "config root" where the Settings.toml file to be used is located.
+pub fn migrate_settings0_9_3_to_0_10_0(config_root: String) -> Result<PathBuf> {
+	let config_root = PathBuf::from(config_root);
+	let settings_file = config_root.join(SETTINGS_IN_CONFIG_ROOT);
 
 	if !settings_file.is_file() {
 		tracing::warn!("Please check that the Settings.toml file exists at {settings_file:?}");
-		return Ok(())
+		return Ok(config_root)
 	}
 
 	std::fs::copy(settings_file.clone(), settings_file.with_extension("toml.0_9_2.backup"))
@@ -67,7 +71,7 @@ pub fn migrate_settings0_9_3_to_0_10_0(config_root: String) -> Result<()> {
 		};
 
 	if !migrate {
-		return Ok(())
+		return Ok(config_root)
 	}
 
 	tracing::info!("Migrating settings to 0.9.3");
@@ -116,13 +120,20 @@ pub fn migrate_settings0_9_3_to_0_10_0(config_root: String) -> Result<()> {
 
 	rename_btc_rpc_user_and_rpc_password(&mut new_settings_table);
 
+	let tmp_config_root = config_root.join("migrated");
+	let tmp_config_settings = tmp_config_root.join(SETTINGS_IN_CONFIG_ROOT);
+
+	// backup the old settings into the temp location
+	std::fs::copy(settings_file.clone(), tmp_config_settings.with_extension("toml.0_9_3.backup"))
+		.context("Unable to create backup of Settings.toml")?;
+
 	fs::write(
-		settings_file,
+		&tmp_config_settings,
 		toml::to_string(&new_settings_table).context("Unable to serialize new Settings to TOML")?,
 	)
 	.context("Unable to write to {settings_file} for migration")?;
 
-	Ok(())
+	Ok(tmp_config_root)
 }
 
 fn remove_node_from_endpoint_names(settings_table: &mut Map<String, Value>) {