wait_for - Read file and perform comparisons using bytes to avoid decode errors (#78317)

* wait_for - Read file and perform comparisons using bytes to avoid decode errors. Fixes #78214

* Write non-ascii via script instead of static file

* Use contexlib.closing to support py27 context manager

* Use executable from task, instead of shebang

* Update encoded bytes to utf16

changelogs/fragments/78214-wait-for-compare-bytes.yml

@@ -0,0 +1,3 @@
+bugfixes:
+- wait_for - Read file and perform comparisons using bytes to avoid decode errors
+  (https://github.com/ansible/ansible/issues/78214)

lib/ansible/modules/wait_for.py

@@ -224,9 +224,11 @@ match_groupdict:
 '''
 
 import binascii
+import contextlib
 import datetime
 import errno
 import math
+import mmap
 import os
 import re
 import select
@@ -236,7 +238,7 @@ import traceback
 
 from ansible.module_utils.basic import AnsibleModule, missing_required_lib
 from ansible.module_utils.common.sys_info import get_platform_subclass
-from ansible.module_utils._text import to_native
+from ansible.module_utils._text import to_bytes
 
 
 HAS_PSUTIL = False
@@ -496,14 +498,22 @@ def main():
     delay = module.params['delay']
     port = module.params['port']
     state = module.params['state']
+
     path = module.params['path']
+    b_path = to_bytes(path, errors='surrogate_or_strict', nonstring='passthru')
+
     search_regex = module.params['search_regex']
+    b_search_regex = to_bytes(search_regex, errors='surrogate_or_strict', nonstring='passthru')
+
     msg = module.params['msg']
 
     if search_regex is not None:
-        compiled_search_re = re.compile(search_regex, re.MULTILINE)
+        try:
+            b_compiled_search_re = re.compile(b_search_regex, re.MULTILINE)
+        except re.error as e:
+            module.fail_json(msg="Invalid regular expression: %s" % e)
     else:
-        compiled_search_re = None
+        b_compiled_search_re = None
 
     match_groupdict = {}
     match_groups = ()
@@ -536,7 +546,7 @@ def main():
         while datetime.datetime.utcnow() < end:
             if path:
                 try:
-                    if not os.access(path, os.F_OK):
+                    if not os.access(b_path, os.F_OK):
                         break
                 except IOError:
                     break
@@ -562,7 +572,7 @@ def main():
         while datetime.datetime.utcnow() < end:
             if path:
                 try:
-                    os.stat(path)
+                    os.stat(b_path)
                 except OSError as e:
                     # If anything except file not present, throw an error
                     if e.errno != 2:
@@ -571,22 +581,20 @@ def main():
                     # file doesn't exist yet, so continue
                 else:
                     # File exists.  Are there additional things to check?
-                    if not compiled_search_re:
+                    if not b_compiled_search_re:
                         # nope, succeed!
                         break
                     try:
-                        f = open(path)
-                        try:
-                            search = re.search(compiled_search_re, f.read())
-                            if search:
-                                if search.groupdict():
-                                    match_groupdict = search.groupdict()
-                                if search.groups():
-                                    match_groups = search.groups()
+                        with open(b_path, 'rb') as f:
+                            with contextlib.closing(mmap.mmap(f.fileno(), 0, access=mmap.ACCESS_READ)) as mm:
+                                search = b_compiled_search_re.search(mm)
+                                if search:
+                                    if search.groupdict():
+                                        match_groupdict = search.groupdict()
+                                    if search.groups():
+                                        match_groups = search.groups()
 
-                                break
-                        finally:
-                            f.close()
+                                    break
                     except IOError:
                         pass
             elif port:
@@ -598,8 +606,8 @@ def main():
                     pass
                 else:
                     # Connected -- are there additional conditions?
-                    if compiled_search_re:
-                        data = ''
+                    if b_compiled_search_re:
+                        b_data = b''
                         matched = False
                         while datetime.datetime.utcnow() < end:
                             max_timeout = math.ceil(_timedelta_total_seconds(end - datetime.datetime.utcnow()))
@@ -612,8 +620,8 @@ def main():
                             if not response:
                                 # Server shutdown
                                 break
-                            data += to_native(response, errors='surrogate_or_strict')
-                            if re.search(compiled_search_re, data):
+                            b_data += response
+                            if b_compiled_search_re.search(b_data):
                                 matched = True
                                 break
 

test/integration/targets/wait_for/files/write_utf16.py

@@ -0,0 +1,20 @@
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+import sys
+
+# utf16 encoded bytes
+# to ensure wait_for doesn't have any encoding errors
+data = (
+    b'\xff\xfep\x00r\x00e\x00m\x00i\x00\xe8\x00r\x00e\x00 \x00i\x00s\x00 '
+    b'\x00f\x00i\x00r\x00s\x00t\x00\n\x00p\x00r\x00e\x00m\x00i\x00e\x00'
+    b'\x00\x03r\x00e\x00 \x00i\x00s\x00 \x00s\x00l\x00i\x00g\x00h\x00t\x00'
+    b'l\x00y\x00 \x00d\x00i\x00f\x00f\x00e\x00r\x00e\x00n\x00t\x00\n\x00\x1a'
+    b'\x048\x04@\x048\x04;\x04;\x048\x04F\x040\x04 \x00i\x00s\x00 \x00C\x00y'
+    b'\x00r\x00i\x00l\x00l\x00i\x00c\x00\n\x00\x01\xd8\x00\xdc \x00a\x00m'
+    b'\x00 \x00D\x00e\x00s\x00e\x00r\x00e\x00t\x00\n\x00\n'
+    b'completed\n'
+)
+
+with open(sys.argv[1], 'wb') as f:
+    f.write(data)

test/integration/targets/wait_for/tasks/main.yml

@@ -104,6 +104,16 @@
     - waitfor['match_groupdict']['foo'] == 'data'
     - waitfor['match_groups'] == ['data', '123']
 
+- name: write non-ascii file
+  script: write_utf16.py "{{remote_tmp_dir}}/utf16.txt"
+  args:
+    executable: '{{ ansible_facts.python.executable }}'
+
+- name: test non-ascii file
+  wait_for:
+    path: "{{remote_tmp_dir}}/utf16.txt"
+    search_regex: completed
+
 - name: test wait for port timeout
   wait_for:
     port: 12121