diff --git a/client-cli/pvc/lib/node.py b/client-cli/pvc/lib/node.py index 062d5268..befb1c5d 100644 --- a/client-cli/pvc/lib/node.py +++ b/client-cli/pvc/lib/node.py @@ -21,6 +21,8 @@ import time +from collections import deque + import pvc.lib.ansiprint as ansiprint from pvc.lib.common import call_api @@ -107,7 +109,9 @@ def follow_node_log(config, node, lines=10): API schema: {"name":"{nodename}","data":"{node_log}"} """ # We always grab 200 to match the follow call, but only _show_ `lines` number - params = {"lines": 200} + max_lines = 200 + + params = {"lines": max_lines} response = call_api( config, "get", "/node/{node}/log".format(node=node), params=params ) @@ -117,42 +121,50 @@ def follow_node_log(config, node, lines=10): # Shrink the log buffer to length lines node_log = response.json()["data"] - shrunk_log = node_log.split("\n")[-int(lines) :] - loglines = "\n".join(shrunk_log) + full_log = node_log.split("\n") + shrunk_log = full_log[-int(lines) :] # Print the initial data and begin following - print(loglines, end="") - print("\n", end="") + for line in shrunk_log: + print(line) + + # Create the deque we'll use to buffer loglines + loglines = deque(full_log, max_lines) while True: + # Wait half a second + time.sleep(0.5) + # Grab the next line set (200 is a reasonable number of lines per half-second; any more are skipped) try: - params = {"lines": 200} + params = {"lines": max_lines} response = call_api( config, "get", "/node/{node}/log".format(node=node), params=params ) new_node_log = response.json()["data"] except Exception: break + # Split the new and old log strings into constitutent lines - old_node_loglines = node_log.split("\n") new_node_loglines = new_node_log.split("\n") - # Set the node log to the new log value for the next iteration - node_log = new_node_log + # Find where in the new lines the last entryin the ongoing deque is + start_idx = 0 + for idx, line in enumerate(new_node_loglines): + if line == loglines[-1]: + start_idx = idx - # Get the difference between the two sets of lines - diff_node_loglines = [ - x for x in new_node_loglines if x not in old_node_loglines - ] + # Get the new lines starting from the found index plus one + diff_node_loglines = new_node_loglines[start_idx + 1 :] - # If there's a difference, print it out + # If there's a difference, add the lines to the ongling deque and print then out if len(diff_node_loglines) > 0: - print("\n".join(diff_node_loglines), end="") - print("\n", end="") + for line in diff_node_loglines: + loglines.append(line) + print(line) - # Wait half a second - time.sleep(0.5) + del new_node_loglines + del diff_node_loglines return True, ""