Add zmq2edi munin stats script

1 files changed, 148 insertions, 0 deletions

diff --git a/doc/stats_zmq2edi_munin.py b/doc/stats_zmq2edi_munin.py
new file mode 100644
index 0000000..cf84afc
--- /dev/null
+++ b/doc/stats_zmq2edi_munin.py
@@ -0,0 +1,148 @@
+#!/usr/bin/env python3
+#
+# A munin plugin for ODR-ZMQ2EDI
+#
+# Reads the logfile, and the previously rotated logfile (suffixed by .1) and
+# analyses the output. Generates a graph with percentage of frames late, and a
+# graph with min/max wait time.
+#
+# Copy this to /etc/munin/plugins/stats_zmq2edi_munin
+# and make it executable (chmod +x)
+#
+# Then make sure that zmq2edi log output gets written to LOGFILE below,
+# and setup up a logrotate script to rotate the log. The rotated log
+# filename must be appended with .1
+
+# Every six seconds a line is output. We are polled in 5 min = 300s intervals
+NUM_LINES = int(300 / 6)
+LOGFILE = "/var/log/supervisor/zmq2edi.log"
+
+import time
+import sys
+import os
+import re
+
+munin_config = """
+multigraph wait_time_zmq2edi
+graph_title zmq2edi wait_time
+graph_order high low
+graph_args --base 1000
+graph_vlabel max/min wait times during last ${graph_period}
+graph_category zmq2edi
+graph_info This graph shows the min and max wait times
+
+high.info Max wait time
+high.label Max wait time ms
+high.min 0
+high.warning 1:
+low.info Min wait time
+low.label Min wait time ms
+low.min -6000
+low.warning 1:
+
+multigraph late_packets_zmq2edi
+graph_title EDI packets delivered too late
+graph_order late
+graph_args --base 1000
+graph_vlabel late packets during last ${graph_period}
+graph_category zmq2edi
+graph_info This graph shows the number late EDI packets (250 packets = 6 seconds)
+
+late.info Number of late packets
+late.label Number of late packets
+late.min 0
+late.max %s
+late.warning 0:0
+""" % (NUM_LINES * 250,)
+
+def parse_logs():
+    # example lines:
+    #  Buffering time statistics [milliseconds]: min: 907.799 max: 981.409 mean: 944.335 stdev: 26.827 late: 0 of 250 (0%)
+    # Values might also be in scientific form, e.g. -1.80938e+07
+    re_logline = re.compile(r"""Buffering time statistics.* min: (.+) max: (.+) mean: (.+) stdev: (.+) late: (.+) of 250""", flags=re.ASCII)
+
+    # The following lines are output at startup and during a reset respectively:
+    startup_pattern = "starting up"
+    backoff_pattern = "Backoff"
+
+    lines = []
+
+    # Check that the file exists and was last written to in the previous 2* 6s,
+    # otherwise assume the tool isn't running
+    if not os.path.exists(LOGFILE) or (time.time() - os.stat(LOGFILE).st_mtime) > 12:
+        num_late = None
+        t_min_period = None
+        t_max_period = None
+    else:
+        # Keep only the last NUM_LINES
+
+        # Read the previously rotated logfile too to make sure we have enough data
+        for fname in [LOGFILE+ ".1", LOGFILE]:
+            if os.path.exists(fname):
+                with open(fname, "r") as fd:
+                    for line in fd:
+                        lines.append(line)
+                        if len(lines) > NUM_LINES:
+                            del lines[0]
+
+        # Calculate min, max over the whole period, and sum the number of late
+        num_late = 0
+        t_min_period = None
+        t_max_period = None
+        num_statistics = 0
+
+        for line in lines:
+            if startup_pattern in line:
+                num_late += 250
+            elif backoff_pattern in line:
+                num_late += 250
+            else:
+                match = re_logline.search(line)
+                if match:
+                    num_statistics += 1
+                    t_min = float(match.group(1))
+                    t_max = float(match.group(2))
+                    t_mean = float(match.group(3))
+                    stdev = float(match.group(4))
+                    late = int(match.group(5))
+
+                    if t_min_period is None or t_min < t_min_period:
+                        t_min_period = t_min
+
+                    if t_max_period is None or t_max > t_max_period:
+                        t_max_period = t_max
+
+                    if num_late is None:
+                        num_late = 0
+
+                    num_late += late
+
+    # The min can take extremely low values, we clamp it here to -6 seconds
+    # to keep the graph readable
+    if t_min_period is not None and t_min_period < -6000:
+        t_min_period = -6000
+
+    return num_late, round(t_min_period) if t_min_period is not None else None, round(t_max_period) if t_max_period is not None else None
+
+def muninify(value):
+    """ According to http://guide.munin-monitoring.org/en/latest/develop/plugins/plugin-concise.html#plugin-concise
+    "If the plugin - for any reason - has no value to report, then it may send the value U for undefined."
+    """
+    return 'U' if value is None else value
+
+# No arguments means that munin wants values
+if len(sys.argv) == 1:
+    num_late, t_min, t_max = parse_logs()
+
+    munin_values = "multigraph wait_time_zmq2edi\n"
+    munin_values += "high.value {}\n".format(muninify(t_max))
+    munin_values += "low.value {}\n".format(muninify(t_min))
+
+    munin_values += "multigraph late_packets_zmq2edi\n"
+    munin_values += "late.value {}\n".format(muninify(num_late))
+    print(munin_values)
+
+elif len(sys.argv) == 2 and sys.argv[1] == "config":
+    print(munin_config)
+else:
+    sys.exit(1)