pytest: Add a test for the cln-plugin logging integration

plugins/examples/cln-plugin-startup.rs

@@ -6,9 +6,10 @@ use tokio;
 
 #[tokio::main]
 async fn main() -> Result<(), anyhow::Error> {
-    env_logger::init();
-
     let (plugin, stdin) = Builder::new((), tokio::io::stdin(), tokio::io::stdout()).build();
-    plugin.run(stdin).await;
-    Ok(())
+    tokio::spawn(async {
+        tokio::time::sleep(tokio::time::Duration::from_millis(1000)).await;
+        log::info!("Hello world");
+    });
+    plugin.run(stdin).await
 }

tests/test_cln_rs.py

@@ -2,7 +2,6 @@ from fixtures import *  # noqa: F401,F403
 from pathlib import Path
 from pyln.testing.utils import env, TEST_NETWORK
 import subprocess
-import os
 import pytest
 
 
@@ -12,8 +11,6 @@ pytestmark = pytest.mark.skipif(
     reason='RUST is not enabled, skipping rust-dependent tests'
 )
 
-os.environ['RUST_LOG'] = "trace"
-
 
 def test_rpc_client(node_factory):
     l1 = node_factory.get_node()
@@ -21,3 +18,17 @@ def test_rpc_client(node_factory):
     rpc_path = Path(l1.daemon.lightning_dir) / TEST_NETWORK / "lightning-rpc"
     out = subprocess.check_output([bin_path, rpc_path], stderr=subprocess.STDOUT)
     assert(b'0266e4598d1d3c415f572a8488830b60f7e744ed9235eb0b1ba93283b315c03518' in out)
+
+
+def test_plugin_start(node_factory):
+   """Start a minimal plugin and ensure it is well-behaved
+   """
+   bin_path = Path.cwd() / "target" / "debug" / "examples" / "cln-plugin-startup"
+   l1 = node_factory.get_node(options={"plugin": str(bin_path)})
+
+   # The plugin should be in the list of active plugins
+   plugins = l1.rpc.plugin('list')['plugins']
+   assert len([p for p in plugins if 'cln-plugin-startup' in p['name'] and p['active']]) == 1
+
+   # Logging should also work through the log integration
+   l1.daemon.wait_for_log(r'Hello world')