Don't crash on a malformed log entry. Move lazy parse of struct.
Austin asked to be resilient when the log has a truncated final entry.
The lazy parsing of struct part of an entry belongs in LogEntry, not
in the reader.
Change-Id: I81d76a116609ac73834863fdd15d2d657d24deaf
diff --git a/frc971/analysis/logentry.py b/frc971/analysis/logentry.py
index 5b9a2ed..3069af0 100644
--- a/frc971/analysis/logentry.py
+++ b/frc971/analysis/logentry.py
@@ -1,7 +1,6 @@
#!/usr/bin/python3
import re
-import sys
"""
A regular expression to match the envelope part of the log entry.
@@ -32,10 +31,11 @@
def __init__(self, line):
"""Populates a LogEntry from a line."""
+ self.line = line
m = LOG_RE.match(line)
if m is None:
print("LOG_RE failed on", line)
- sys.exit(1)
+ return
self.name = m.group(1)
self.pid_index = int(m.group(2))
self.msg_index = int(m.group(3))
@@ -44,6 +44,7 @@
self.filename = m.group(6)
self.linenumber = m.group(7)
self.msg = m.group(8)
+ self.struct_name = None
def __str__(self):
"""Formats the data cleanly."""
@@ -56,6 +57,10 @@
Returns:
struct_name, struct_type, json dict.
"""
+ if self.struct_name:
+ # We've already parsed the structural part. Return the cached result
+ return (self.struct_name, self.struct_type, self.struct_json)
+
struct_name_index = self.msg.find(':')
struct_name = self.msg[0:struct_name_index]
@@ -109,6 +114,11 @@
# Now that we have tokens, parse them.
self.JsonizeTokens(json, tokens, 1)
+ # Cache the result to avoid having to reparse.
+ self.struct_name = struct_name
+ self.struct_type = struct_type
+ self.struct_json = json
+
return (struct_name, struct_type, json)
def JsonizeTokens(self, json, tokens, token_index):
diff --git a/frc971/analysis/logreader.py b/frc971/analysis/logreader.py
index 34f1b01..c59487b 100644
--- a/frc971/analysis/logreader.py
+++ b/frc971/analysis/logreader.py
@@ -47,7 +47,11 @@
"""
with open(f, 'r') as fd:
for line in fd:
- self.HandleLine(line)
+ try:
+ self.HandleLine(line)
+ except Exception as ex:
+ # It's common for the last line of the file to be malformed.
+ print("Ignoring malformed log entry: ", line)
def HandleLine(self, line):
"""
@@ -60,7 +64,6 @@
None
"""
pline = LogEntry(line)
- pline_data = None
for key in self.signal:
value = self.signal[key]
@@ -79,12 +82,9 @@
# Make sure that we're looking at the right binary structure instance.
if binary == pline.name:
if pline.msg.startswith(struct_instance_name + ': '):
- # Parse the structure once.
- if pline_data is None:
- _, _, pline_data = pline.ParseStruct()
# Traverse the structure as specified in `data_search_path`.
# This lets the user access very deeply nested structures.
- data = pline_data
+ _, _, data = pline.ParseStruct()
for path in data_search_path:
data = data[path]