Add extract_logs action to concatenate logs after log rotate (#471)

Author: pavel-shirshov

ansible/library/extract_log.py

@@ -0,0 +1,220 @@
+#!/usr/bin/python
+
+DOCUMENTATION = '''
+module:  extract_log
+version_added:  "1.0"
+short_description: Unrotate logs and extract information starting from a row with predefined string
+description: The module scans the 'directory' in search of files which filenames start with 'file_prefix'.
+The found files are ungzipped and combined together in the rotation order. After that all lines after
+'start_string' are copied into a file with name 'target_filename'.
+
+Options:
+    - option-name: directory
+      description: a name of a directory with target log files
+      required: True
+      Default: None
+
+    - option-name: file_prefix
+      description: a prefix of target log files
+      required: True
+      Default: None
+
+    - option-name: start_string
+      description: a string which last copy is used as a start tag for extracting log information
+      required: True
+      Default: None
+
+    - option-name: target_filename
+      description: a filename of a file where the extracted lines will be saved
+      required: True
+      Default: None
+
+'''
+
+EXAMPLES = '''
+- name: Extract all syslog entries since the last reboot
+  extract_log:
+    directory: '/var/log'
+    file_prefix: 'syslog'
+    start_string: 'Initializing cgroup subsys cpuset'
+    target_filename: '/tmp/syslog'
+
+- name: Copy the exctracted syslog entries to the local machine
+  fetch:
+    src: '/tmp/syslog'
+    dest: '/tmp/'
+    flat: yes
+
+- name: Extract all sairedis.rec entries since the last reboot
+  extract_log:
+    directory: '/var/log/swss'
+    file_prefix: 'sairedis.rec'
+    start_string: 'recording on:'
+    target_filename: '/tmp/sairedis.rec'
+
+- name: Copy the exctracted sairedis.rec entries to the local machine
+  fetch:
+    src: '/tmp/sairedis.rec'
+    dest: '/tmp/'
+    flat: yes
+
+- name: Extract all swss.rec entries since the last reboot
+  extract_log:
+    directory: '/var/log/swss'
+    file_prefix: 'swss.rec'
+    start_string: 'recording started'
+    target_filename: '/tmp/swss.rec'
+
+- name: Copy the exctracted swss.rec entries to the local machine
+  fetch:
+    src: '/tmp/swss.rec'
+    dest: '/tmp/'
+    flat: yes
+'''
+
+import os
+import gzip
+import re
+import sys
+from datetime import datetime
+from ansible.module_utils.basic import *
+
+from pprint import pprint
+
+
+def extract_line(directory, filename, target_string):
+    path = os.path.join(directory, filename)
+    file = None
+    if 'gz' in path:
+        file = gzip.GzipFile(path)
+    else:
+        file = open(path)
+    result = None
+    with file:
+        result = [(filename, line) for line in file if target_string in line]
+    return result
+
+
+def list_files(directory, prefixname):
+    return [filename for filename in os.listdir(directory) if filename.startswith(prefixname)]
+
+
+def extract_number(s):
+    ns = re.findall(r'\d+', s)
+    if len(ns) == 0:
+        return 0
+    else:
+        return int(ns[0])
+
+
+def convert_date(s):
+    str_date = re.findall(r'^\S{3}\s{1,2}\d{1,2} \d{2}:\d{2}:\d{2}\.?\d*', s)[0]
+    dt = None
+    try:
+        dt = datetime.strptime(str_date, '%b %d %X.%f')
+    except ValueError:
+        pass
+    if dt is None:
+        dt = datetime.strptime(str_date, '%b %d %X')
+
+    return dt
+
+
+def comparator(l, r):
+    nl = extract_number(l[0])
+    nr = extract_number(r[0])
+    if nl == nr:
+        dl = convert_date(l[1])
+        dr = convert_date(r[1])
+        if dl == dr:
+            return 0
+        elif dl < dr:
+            return -1
+        else:
+            return 1
+    elif nl > nr:
+        return -1
+    else:
+        return 1
+
+
+def filename_comparator(l, r):
+    nl = extract_number(l)
+    nr = extract_number(r)
+    if nl == nr:
+        return 0
+    elif nl > nr:
+        return -1
+    else:
+        return 1
+
+
+def extract_latest_line_with_string(directory, filenames, start_string):
+    target_lines = []
+    for filename in filenames:
+        target_lines.extend(extract_line(directory, filename, start_string))
+
+    sorted_target_lines = sorted(target_lines, cmp=comparator)
+
+    return sorted_target_lines[-1]
+
+
+def calculate_files_to_copy(filenames, file_with_latest_line):
+    sorted_filenames = sorted(filenames, cmp=filename_comparator)
+    files_to_copy = []
+    do_copy = False
+    for filename in sorted_filenames:
+        if filename == file_with_latest_line:
+            do_copy = True
+        if do_copy:
+            files_to_copy.append(filename)
+
+    return files_to_copy
+
+
+def combine_logs_and_save(directory, filenames, start_string, target_filename):
+    do_copy = False
+    with open(target_filename, 'w') as fp:
+        for filename in filenames:
+            path = os.path.join(directory, filename)
+            file = None
+            if 'gz' in path:
+                file = gzip.GzipFile(path)
+            else:
+                file = open(path)
+            with file:
+                for line in file:
+                    if line == start_string:
+                        do_copy = True
+                    if do_copy:
+                        fp.write(line)
+
+
+def extract_log(directory, prefixname, target_string, target_filename):
+    filenames = list_files(directory, prefixname)
+    file_with_latest_line, latest_line = extract_latest_line_with_string(directory, filenames, target_string)
+    files_to_copy = calculate_files_to_copy(filenames, file_with_latest_line)
+    combine_logs_and_save(directory, files_to_copy, latest_line, target_filename)
+
+
+def main():
+    module = AnsibleModule(
+        argument_spec=dict(
+            directory=dict(required=True, type='str'),
+            file_prefix=dict(required=True, type='str'),
+            start_string=dict(required=True, type='str'),
+            target_filename=dict(required=True, type='str'),
+        ),
+        supports_check_mode=False)
+
+    p = module.params;
+    try:
+        extract_log(p['directory'], p['file_prefix'], p['start_string'], p['target_filename'])
+    except:
+        err = str(sys.exc_info())
+        module.fail_json(msg="Error: %s" % err)
+    module.exit_json()
+
+
+if __name__ == '__main__':
+    main()

ansible/roles/test/tasks/fast-reboot.yml

@@ -134,3 +134,42 @@
     - name: Remove existing ip from ptf host
       script: roles/test/files/helpers/remove_ip.sh
       delegate_to: "{{ ptf_host }}"
+
+    - name: Extract all syslog entries since the last reboot
+      extract_log:
+        directory: '/var/log'
+        file_prefix: 'syslog'
+        start_string: 'Initializing cgroup subsys cpuset'
+        target_filename: '/tmp/syslog'
+
+    - name: Copy the exctracted syslog entries to the local machine
+      fetch:
+        src: '/tmp/syslog'
+        dest: '/tmp/'
+        flat: yes
+
+    - name: Extract all sairedis.rec entries since the last reboot
+      extract_log:
+        directory: '/var/log/swss'
+        file_prefix: 'sairedis.rec'
+        start_string: 'recording on:'
+        target_filename: '/tmp/sairedis.rec'
+
+    - name: Copy the exctracted sairedis.rec entries to the local machine
+      fetch:
+        src: '/tmp/sairedis.rec'
+        dest: '/tmp/'
+        flat: yes
+
+    - name: Extract all swss.rec entries since the last reboot
+      extract_log:
+        directory: '/var/log/swss'
+        file_prefix: 'swss.rec'
+        start_string: 'recording started'
+        target_filename: '/tmp/swss.rec'
+
+    - name: Copy the exctracted swss.rec entries to the local machine
+      fetch:
+        src: '/tmp/swss.rec'
+        dest: '/tmp/'
+        flat: yes