Fix: diagnostics function write error result bug (#649)

* fix output writing for diagnostics function

* log on ssh connect

aztk/spark/client/cluster/helpers/diagnostics.py

@@ -6,6 +6,14 @@
 from aztk.utils import helpers
 
 
+def _write_error(stream, node_output):
+    stream.write(node_output.error)
+
+
+def _write_output(stream, node_output):
+    stream.write(node_output.output)
+
+
 def _run(spark_cluster_operations, cluster_id, output_directory=None, brief=False):
     # copy debug program to each node
     output = spark_cluster_operations.copy(
@@ -18,9 +26,10 @@ def _run(spark_cluster_operations, cluster_id, output_directory=None, brief=Fals
         local_path = os.path.join(os.path.abspath(output_directory), "debug.zip")
         result = spark_cluster_operations.download(cluster_id, remote_path, local_path, host=True)
 
-        # write run output to debug/ directory
-        with open(os.path.join(output_directory, "debug-output.txt"), 'w', encoding="UTF-8") as f:
-            [f.write(node_output.output + '\n') for node_output in run_output]
+        # write run output or error to debug/ directory
+        with open(os.path.join(output_directory, "debug-output.txt"), 'w', encoding="UTF-8") as stream:
+            for node_output in run_output:
+                _write_error(stream, node_output) if node_output.error else _write_output(stream, node_output)
     else:
         result = spark_cluster_operations.download(cluster_id, remote_path, host=True)
 

aztk/utils/ssh.py

@@ -77,6 +77,7 @@ def connect(hostname, port=22, username=None, password=None, pkey=None, timeout=
         ssh_key = None
 
     timeout = timeout or 20
+    logging.debug("Connecting to {}@{}:{}, timeout={}".format(username, hostname, port, timeout))
     try:
         client.connect(hostname, port=port, username=username, password=password, pkey=ssh_key, timeout=timeout)
     except socket.timeout:
@@ -206,7 +207,6 @@ def node_copy(node_id,
             output = sftp_client.put(source_path, destination_path).__str__()
             return NodeOutput(node_id, output, None)
     except (IOError, PermissionError) as e:
-        raise e
         return NodeOutput(node_id, None, e)
     finally:
         sftp_client.close()