From bca96728ee5220cd41e4b75844122be4cd576751 Mon Sep 17 00:00:00 2001
From: Vincent Zhang <vincent.zhang@dfinity.org>
Date: Tue, 29 Oct 2024 18:33:39 +0800
Subject: [PATCH 1/3] Improve the error message for 'dfx deploy'.

---
 e2e/tests-dfx/deploy.bash      | 5 +++++
 src/dfx/src/commands/deploy.rs | 4 +++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/e2e/tests-dfx/deploy.bash b/e2e/tests-dfx/deploy.bash
index 709f912f8e..b93b129292 100644
--- a/e2e/tests-dfx/deploy.bash
+++ b/e2e/tests-dfx/deploy.bash
@@ -187,6 +187,11 @@ teardown() {
   assert_contains "Creating a wallet canister"
 }
 
+@test "deploy without starting returns the correct error message" {
+  assert_command_fail dfx deploy
+  assert_contains "Failed to fetch the root key, did you run 'dfx start' to start the local replica?"
+}
+
 @test "can deploy gzip wasm" {
   jq '.canisters.hello_backend.gzip=true' dfx.json | sponge dfx.json
   dfx_start
diff --git a/src/dfx/src/commands/deploy.rs b/src/dfx/src/commands/deploy.rs
index 78751a62de..d3ab482693 100644
--- a/src/dfx/src/commands/deploy.rs
+++ b/src/dfx/src/commands/deploy.rs
@@ -162,7 +162,9 @@ pub fn exec(env: &dyn Environment, opts: DeployOpts) -> DfxResult {
     let call_sender = CallSender::from(&opts.wallet, env.get_network_descriptor())
         .map_err(|e| anyhow!("Failed to determine call sender: {}", e))?;
 
-    runtime.block_on(fetch_root_key_if_needed(&env))?;
+    // This is where we try to talk to replica first.
+    runtime.block_on(fetch_root_key_if_needed(&env))
+        .map_err(|e| anyhow!("Failed to fetch the root key, did you run 'dfx start' to start the local replica?\n{}", e))?;
 
     runtime.block_on(deploy_canisters(
         &env,

From cf4ef4010cae24f35e5b1a974ba1cad5cff61324 Mon Sep 17 00:00:00 2001
From: Vincent Zhang <vincent.zhang@dfinity.org>
Date: Tue, 29 Oct 2024 21:33:35 +0800
Subject: [PATCH 2/3] Move the error handling to 'fetch_root_key_if_needed'.

---
 src/dfx/src/commands/deploy.rs | 4 +---
 src/dfx/src/lib/root_key.rs    | 5 +++--
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/dfx/src/commands/deploy.rs b/src/dfx/src/commands/deploy.rs
index d3ab482693..78751a62de 100644
--- a/src/dfx/src/commands/deploy.rs
+++ b/src/dfx/src/commands/deploy.rs
@@ -162,9 +162,7 @@ pub fn exec(env: &dyn Environment, opts: DeployOpts) -> DfxResult {
     let call_sender = CallSender::from(&opts.wallet, env.get_network_descriptor())
         .map_err(|e| anyhow!("Failed to determine call sender: {}", e))?;
 
-    // This is where we try to talk to replica first.
-    runtime.block_on(fetch_root_key_if_needed(&env))
-        .map_err(|e| anyhow!("Failed to fetch the root key, did you run 'dfx start' to start the local replica?\n{}", e))?;
+    runtime.block_on(fetch_root_key_if_needed(&env))?;
 
     runtime.block_on(deploy_canisters(
         &env,
diff --git a/src/dfx/src/lib/root_key.rs b/src/dfx/src/lib/root_key.rs
index 6fda3a4b5c..7e6877f727 100644
--- a/src/dfx/src/lib/root_key.rs
+++ b/src/dfx/src/lib/root_key.rs
@@ -1,11 +1,12 @@
 use crate::{lib::error::DfxResult, Environment};
-
+use anyhow::anyhow;
 use dfx_core::network::root_key;
 
 pub async fn fetch_root_key_if_needed(env: &dyn Environment) -> DfxResult {
     let agent = env.get_agent();
     let network = env.get_network_descriptor();
-    root_key::fetch_root_key_when_non_mainnet(agent, network).await?;
+    root_key::fetch_root_key_when_non_mainnet(agent, network).await
+        .map_err(|e| anyhow!("Failed to fetch the root key, did you run 'dfx start' to start the local replica?\n{}", e))?;
     Ok(())
 }
 

From 260c9577fd655bc9699e945ad39c0fba15b0733c Mon Sep 17 00:00:00 2001
From: Vincent Zhang <vincent.zhang@dfinity.org>
Date: Tue, 29 Oct 2024 22:32:55 +0800
Subject: [PATCH 3/3] Update CHANGELOG.md.

---
 CHANGELOG.md | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7a29863ab7..6446d99042 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,14 @@ Allow setting permissions lists in init arguments just like in upgrade arguments
 - Module hash: 2c24b5e1584890a7965011d5d1d827aca68c489c9a6308475730420fa53372e8
 - https://github.com/dfinity/sdk/pull/3965
 
+### chore!: improve `dfx deploy` messages.
+
+If users run `dfx deploy` without running `dfx start`, show below messages to indicate what to do next.
+```
+Error: Failed to fetch the root key, did you run 'dfx start' to start the local replica?
+An error happened during communication with the replica: error sending request for url (http://127.0.0.1:4943/api/v2/status)
+```
+
 # 0.24.2
 
 ### feat: Support canister log allowed viewer list