fix: dfx ping uses the anonymous identity and does not require dfx.json

CHANGELOG.adoc

@@ -48,6 +48,10 @@ and then exit immediately.
 This avoids interference between a dfx process performing cleanup at shutdown and
 a dfx process that is starting.
 
+=== fix: dfx ping no longer creates a default identity
+
+dfx ping now uses the anonymous identity, and no longer requires dfx.json to be present.
+
 == Dependencies
 
 == Replica

docs/cli-reference/dfx-ping.md

@@ -2,7 +2,9 @@
 
 Use the `dfx ping` command to check connectivity to the IC or a testnet. This command enables you to verify that you can connect to the environment where you want to deploy to.
 
-Note that you can only run this command from within the project directory structure. For example, if your project name is `hello_world`, your current working directory must be the `hello_world` top-level project directory or one of its subdirectories.
+To ping your local server, please note that you can only run this command from within the project directory structure. For example, if your project name is `hello_world`, your current working directory must be the `hello_world` top-level project directory or one of its subdirectories.
+
+To ping mainnet, you can run `dfx ping ic` from any directory.
 
 ## Basic usage
 

e2e/tests-dfx/identity.bash

@@ -79,12 +79,21 @@ teardown() {
     assert_eq '(false)'
 }
 
-@test "dfx ping creates the default identity on first run" {
-    install_asset identity
+@test "dfx ping does not create a default identity" {
     dfx_start
+
+    assert_file_not_exists "$DFX_CONFIG_ROOT/.config/dfx/identity.json"
+    assert_file_not_exists "$DFX_CONFIG_ROOT/.config/dfx/identity/default/identity.pem"
+
     assert_command dfx ping
+
+    assert_file_not_exists "$DFX_CONFIG_ROOT/.config/dfx/identity.json"
+    assert_file_not_exists "$DFX_CONFIG_ROOT/.config/dfx/identity/default/identity.pem"
+
     # shellcheck disable=SC2154
-    assert_match 'Creating the "default" identity.' "$stderr"
+    assert_not_match 'Creating' "$stderr"
+    # shellcheck disable=SC2154
+    assert_not_match 'default' "$stderr"
     # shellcheck disable=SC2154
     assert_match "ic_api_version" "$stdout"
 }

e2e/tests-dfx/ping.bash

@@ -34,6 +34,19 @@ teardown() {
     assert_match "\"ic_api_version\""
 }
 
+@test "dfx ping does not require dfx.json" {
+    dfx_start
+    webserver_port=$(cat .dfx/webserver-port)
+
+    mkdir "$DFX_E2E_TEMP_DIR/not-a-project"
+    (
+        cd "$DFX_E2E_TEMP_DIR/not-a-project"
+
+        assert_command dfx ping http://127.0.0.1:"$webserver_port"
+        assert_match "\"ic_api_version\""
+    )
+}
+
 @test "dfx ping succeeds by network name" {
     dfx_start
     assert_command dfx ping local

e2e/utils/_.bash

@@ -145,11 +145,7 @@ dfx_start() {
 
 wait_until_replica_healthy() {
     echo "waiting for replica to become healthy"
-    (
-        # dfx ping has side effects, like creating a default identity.
-        DFX_CONFIG_ROOT="$DFX_E2E_TEMP_DIR/dfx-ping-tmp"
-        dfx ping --wait-healthy
-    )
+    dfx ping --wait-healthy
     echo "replica became healthy"
 }
 

src/dfx/src/commands/ping.rs

@@ -1,7 +1,6 @@
-use crate::config::dfinity::NetworkType;
-use crate::lib::environment::{AgentEnvironment, Environment};
+use crate::lib::environment::{create_agent, Environment};
 use crate::lib::error::{DfxError, DfxResult};
-use crate::lib::network::network_descriptor::NetworkDescriptor;
+use crate::lib::identity::Identity;
 use crate::lib::provider::{
     command_line_provider_to_url, get_network_context, get_network_descriptor,
 };
@@ -28,32 +27,24 @@ pub struct PingOpts {
 }
 
 pub fn exec(env: &dyn Environment, opts: PingOpts) -> DfxResult {
-    env.get_config_or_anyhow()?;
-
     // For ping, "provider" could either be a URL or a network name.
     // If not passed, we default to the "local" network.
-    let network_descriptor =
-        get_network_descriptor(env, opts.network).or_else::<DfxError, _>(|err| {
+    let agent_url = get_network_descriptor(env, opts.network)
+        .and_then(|network_descriptor| {
+            let url = network_descriptor.first_provider()?.to_string();
+            Ok(url)
+        })
+        .or_else::<DfxError, _>(|err| {
             let logger = env.get_logger();
             warn!(logger, "{}", err);
             let network_name = get_network_context()?;
             let url = command_line_provider_to_url(&network_name)?;
-            let is_ic = NetworkDescriptor::is_ic(&network_name, &vec![url.to_string()]);
-            let network_descriptor = NetworkDescriptor {
-                name: "-ping-".to_string(),
-                providers: vec![url],
-                r#type: NetworkType::Ephemeral,
-                is_ic,
-            };
-            Ok(network_descriptor)
+            Ok(url)
         })?;
 
     let timeout = expiry_duration();
-    let env = AgentEnvironment::new(env, network_descriptor, timeout)?;
-
-    let agent = env
-        .get_agent()
-        .ok_or_else(|| anyhow!("Cannot find dfx configuration file in the current working directory. Did you forget to create one?"))?;
+    let identity = Box::new(Identity::anonymous());
+    let agent = create_agent(env.get_logger().clone(), &agent_url, identity, timeout)?;
 
     let runtime = Runtime::new().expect("Unable to create a runtime");
     if opts.wait_healthy {

src/dfx/src/lib/environment.rs

@@ -232,19 +232,14 @@ impl<'a> AgentEnvironment<'a> {
         network_descriptor: NetworkDescriptor,
         timeout: Duration,
     ) -> DfxResult<Self> {
+        let logger = backend.get_logger().clone();
         let mut identity_manager = IdentityManager::new(backend)?;
         let identity = identity_manager.instantiate_selected_identity()?;
+        let url = network_descriptor.first_provider()?;
 
-        let agent_url = network_descriptor.providers.first().with_context(|| {
-            format!(
-                "Network '{}' does not specify any network providers.",
-                network_descriptor.name
-            )
-        })?;
         Ok(AgentEnvironment {
             backend,
-            agent: create_agent(backend.get_logger().clone(), agent_url, identity, timeout)
-                .expect("Failed to construct agent."),
+            agent: create_agent(logger, url, identity, timeout)?,
             network_descriptor: network_descriptor.clone(),
             identity_manager,
         })
@@ -466,26 +461,23 @@ impl ic_agent::agent::http_transport::PasswordManager for AgentClient {
     }
 }
 
-fn create_agent(
+#[context("Failed to create agent with url {}.", url)]
+pub fn create_agent(
     logger: Logger,
     url: &str,
     identity: Box<dyn Identity + Send + Sync>,
     timeout: Duration,
-) -> Option<Agent> {
-    AgentClient::new(logger, url.to_string())
-        .ok()
-        .and_then(|executor| {
-            Agent::builder()
-                .with_transport(
-                    ic_agent::agent::http_transport::ReqwestHttpReplicaV2Transport::create(url)
-                        .unwrap()
-                        .with_password_manager(executor),
-                )
-                .with_boxed_identity(identity)
-                .with_ingress_expiry(Some(timeout))
-                .build()
-                .ok()
-        })
+) -> DfxResult<Agent> {
+    let executor = AgentClient::new(logger, url.to_string())?;
+    let agent = Agent::builder()
+        .with_transport(
+            ic_agent::agent::http_transport::ReqwestHttpReplicaV2Transport::create(url)?
+                .with_password_manager(executor),
+        )
+        .with_boxed_identity(identity)
+        .with_ingress_expiry(Some(timeout))
+        .build()?;
+    Ok(agent)
 }
 
 #[cfg(test)]

src/dfx/src/lib/network/network_descriptor.rs

@@ -1,5 +1,8 @@
 use crate::config::dfinity::NetworkType;
 use crate::config::dfinity::{DEFAULT_IC_GATEWAY, DEFAULT_IC_GATEWAY_TRAILING_SLASH};
+use crate::lib::error::DfxResult;
+
+use anyhow::bail;
 
 #[derive(Clone, Debug)]
 pub struct NetworkDescriptor {
@@ -26,6 +29,17 @@ impl NetworkDescriptor {
         };
         name_match || provider_match
     }
+
+    /// Return the first provider in the list
+    pub fn first_provider(&self) -> DfxResult<&str> {
+        match self.providers.first() {
+            Some(provider) => Ok(provider),
+            None => bail!(
+                "Network '{}' does not specify any network providers.",
+                self.name
+            ),
+        }
+    }
 }
 
 #[cfg(test)]