Introduce --with-faucet for net up using the default chain (#3324)

## Motivation

Right now we have a `--with-faucet-chain` option that both enables starting a faucet and also specifies what chain the faucet will be running on.
`linera faucet` however has a slightly different behavior, in which if you don't specify the chain, it just uses the default chain.

## Proposal

Introduce a `--with-faucet` option that controls whether a faucet will be started, which will by default start a faucet on the default chain, unless the `--faucet-chain` argument is provided.

## Test Plan

Run it locally, see the faucet being started using the default chain as expected, and previous behavior also works

## Release Plan

- Nothing to do / These changes follow the usual release cycle.

CLI.md

@@ -932,7 +932,10 @@ Start a Local Linera Network
 * `--external-protocol <EXTERNAL_PROTOCOL>` — External protocol used, either `grpc` or `grpcs`
 
   Default value: `grpc`
-* `--with-faucet-chain <WITH_FAUCET_CHAIN>` — If present, a faucet is started using the given chain root number (0 for the admin chain, 1 for the first non-admin initial chain, etc)
+* `--with-faucet` — If present, a faucet is started using the chain provided by --faucet-chain, or `ChainId::root(1)` if not provided, as root 0 is usually the admin chain
+
+  Default value: `false`
+* `--faucet-chain <FAUCET_CHAIN>` — When using --with-faucet, this specifies the chain on which the faucet will be started. The chain is specified by its root number (0 for the admin chain, 1 for the first non-admin initial chain, etc)
 * `--faucet-port <FAUCET_PORT>` — The port on which to run the faucet server
 
   Default value: `8080`

linera-client/src/client_options.rs

@@ -1099,10 +1099,16 @@ pub enum NetCommand {
         #[arg(long, default_value = "grpc")]
         external_protocol: String,
 
-        /// If present, a faucet is started using the given chain root number (0 for the
-        /// admin chain, 1 for the first non-admin initial chain, etc).
+        /// If present, a faucet is started using the chain provided by --faucet-chain, or
+        /// `ChainId::root(1)` if not provided, as root 0 is usually the admin chain.
+        #[arg(long, default_value = "false")]
+        with_faucet: bool,
+
+        /// When using --with-faucet, this specifies the chain on which the faucet will be started.
+        /// The chain is specified by its root number (0 for the admin chain, 1 for the first
+        /// non-admin initial chain, etc).
         #[arg(long)]
-        with_faucet_chain: Option<u32>,
+        faucet_chain: Option<u32>,
 
         /// The port on which to run the faucet server
         #[arg(long, default_value = "8080")]

linera-service/src/linera/main.rs

@@ -1613,7 +1613,8 @@ async fn run(options: &ClientOptions) -> Result<i32, anyhow::Error> {
                 path: _,
                 storage: _,
                 external_protocol: _,
-                with_faucet_chain,
+                with_faucet,
+                faucet_chain,
                 faucet_port,
                 faucet_amount,
             } => {
@@ -1628,7 +1629,8 @@ async fn run(options: &ClientOptions) -> Result<i32, anyhow::Error> {
                     *no_build,
                     docker_image_name.clone(),
                     policy_config.into_policy(),
-                    *with_faucet_chain,
+                    *with_faucet,
+                    *faucet_chain,
                     *faucet_port,
                     *faucet_amount,
                 )
@@ -1648,7 +1650,8 @@ async fn run(options: &ClientOptions) -> Result<i32, anyhow::Error> {
                 path,
                 storage,
                 external_protocol,
-                with_faucet_chain,
+                with_faucet,
+                faucet_chain,
                 faucet_port,
                 faucet_amount,
                 ..
@@ -1664,7 +1667,8 @@ async fn run(options: &ClientOptions) -> Result<i32, anyhow::Error> {
                     path,
                     storage,
                     external_protocol.clone(),
-                    *with_faucet_chain,
+                    *with_faucet,
+                    *faucet_chain,
                     *faucet_port,
                     *faucet_amount,
                 )

linera-service/src/linera/net_up_utils.rs

@@ -112,7 +112,8 @@ pub async fn handle_net_up_kubernetes(
     no_build: bool,
     docker_image_name: String,
     policy: ResourceControlPolicy,
-    with_faucet_chain: Option<u32>,
+    with_faucet: bool,
+    faucet_chain: Option<u32>,
     faucet_port: NonZeroU16,
     faucet_amount: Amount,
 ) -> anyhow::Result<()> {
@@ -122,6 +123,12 @@ pub async fn handle_net_up_kubernetes(
     if num_shards < 1 {
         panic!("The local test network must have at least one shard per validator.");
     }
+    if faucet_chain.is_some() {
+        assert!(
+            with_faucet,
+            "--faucet-chain must be provided only with --with-faucet"
+        );
+    }
 
     let shutdown_notifier = CancellationToken::new();
     tokio::spawn(listen_for_shutdown_signals(shutdown_notifier.clone()));
@@ -143,9 +150,11 @@ pub async fn handle_net_up_kubernetes(
         extra_wallets,
         &mut net,
         client,
-        with_faucet_chain,
+        with_faucet,
+        faucet_chain,
         faucet_port,
         faucet_amount,
+        num_other_initial_chains,
     )
     .await?;
     wait_for_shutdown(shutdown_notifier, &mut net, faucet_service).await
@@ -163,7 +172,8 @@ pub async fn handle_net_up_service(
     path: &Option<String>,
     storage: &Option<String>,
     external_protocol: String,
-    with_faucet_chain: Option<u32>,
+    with_faucet: bool,
+    faucet_chain: Option<u32>,
     faucet_port: NonZeroU16,
     faucet_amount: Amount,
 ) -> anyhow::Result<()> {
@@ -208,9 +218,11 @@ pub async fn handle_net_up_service(
         extra_wallets,
         &mut net,
         client,
-        with_faucet_chain,
+        with_faucet,
+        faucet_chain,
         faucet_port,
         faucet_amount,
+        num_other_initial_chains,
     )
     .await?;
     wait_for_shutdown(shutdown_notifier, &mut net, faucet_service).await
@@ -234,13 +246,16 @@ async fn wait_for_shutdown(
     Ok(())
 }
 
+#[allow(clippy::too_many_arguments)]
 async fn create_wallets_and_faucets(
     extra_wallets: Option<usize>,
     net: &mut impl LineraNet,
     client: ClientWrapper,
-    with_faucet_chain: Option<u32>,
+    with_faucet: bool,
+    faucet_chain: Option<u32>,
     faucet_port: NonZeroU16,
     faucet_amount: Amount,
+    num_other_initial_chains: u32,
 ) -> Result<Option<FaucetService>, anyhow::Error> {
     let default_chain = client
         .default_chain()
@@ -317,13 +332,18 @@ async fn create_wallets_and_faucets(
     }
 
     // Run the faucet,
-    let faucet_service = if let Some(faucet_chain) = with_faucet_chain {
+    let faucet_service = if with_faucet {
+        let faucet_chain = if let Some(faucet_chain) = faucet_chain {
+            ChainId::root(faucet_chain)
+        } else {
+            assert!(
+                num_other_initial_chains > 1,
+                "num_other_initial_chains must be greater than 1 if with_faucet is true"
+            );
+            ChainId::root(1)
+        };
         let service = client
-            .run_faucet(
-                Some(faucet_port.into()),
-                ChainId::root(faucet_chain),
-                faucet_amount,
-            )
+            .run_faucet(Some(faucet_port.into()), faucet_chain, faucet_amount)
             .await?;
         Some(service)
     } else {

linera-service/tests/local_net_tests.rs

@@ -664,7 +664,8 @@ async fn test_storage_service_linera_net_up_simple() -> Result<()> {
     command.args([
         "net",
         "up",
-        "--with-faucet-chain",
+        "--with-faucet",
+        "--faucet-chain",
         "1",
         "--faucet-port",
         &port.to_string(),