Bugfixes

--------
 
 - Fix bug in v0.33.3rc1 which caused infinite loops and OOMs
 ([\#3723](https://github.com/matrix-org/synapse/issues/3723))
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Merge tag 'v0.33.3rc2' into matrix-org-hotfixes

Bugfixes
--------

- Fix bug in v0.33.3rc1 which caused infinite loops and OOMs
([\#3723](https://github.com/matrix-org/synapse/issues/3723))

CHANGES.md

@@ -1,3 +1,76 @@
+Synapse 0.33.3rc2 (2018-08-21)
+==============================
+
+Bugfixes
+--------
+
+- Fix bug in v0.33.3rc1 which caused infinite loops and OOMs ([\#3723](https://github.com/matrix-org/synapse/issues/3723))
+
+
+Synapse 0.33.3rc1 (2018-08-21)
+==============================
+
+Features
+--------
+
+- Add support for the SNI extension to federation TLS connections ([\#1491](https://github.com/matrix-org/synapse/issues/1491))
+- Add /_media/r0/config ([\#3184](https://github.com/matrix-org/synapse/issues/3184))
+- speed up /members API and add `at` and `membership` params as per MSC1227 ([\#3568](https://github.com/matrix-org/synapse/issues/3568))
+- implement `summary` block in /sync response as per MSC688 ([\#3574](https://github.com/matrix-org/synapse/issues/3574))
+- Add lazy-loading support to /messages as per MSC1227 ([\#3589](https://github.com/matrix-org/synapse/issues/3589))
+- Add ability to limit number of monthly active users on the server ([\#3633](https://github.com/matrix-org/synapse/issues/3633))
+- Support more federation endpoints on workers ([\#3653](https://github.com/matrix-org/synapse/issues/3653))
+- Basic support for room versioning ([\#3654](https://github.com/matrix-org/synapse/issues/3654))
+- Ability to disable client/server Synapse via conf toggle ([\#3655](https://github.com/matrix-org/synapse/issues/3655))
+- Ability to whitelist specific threepids against monthly active user limiting ([\#3662](https://github.com/matrix-org/synapse/issues/3662))
+- Add some metrics for the appservice and federation event sending loops ([\#3664](https://github.com/matrix-org/synapse/issues/3664))
+- Where server is disabled, block ability for locked out users to read new messages ([\#3670](https://github.com/matrix-org/synapse/issues/3670))
+- set admin uri via config, to be used in error messages where the user should contact the administrator ([\#3687](https://github.com/matrix-org/synapse/issues/3687))
+- Synapse's presence functionality can now be disabled with the "use_presence" configuration option. ([\#3694](https://github.com/matrix-org/synapse/issues/3694))
+- For resource limit blocked users, prevent writing into rooms ([\#3708](https://github.com/matrix-org/synapse/issues/3708))
+
+
+Bugfixes
+--------
+
+- Fix occasional glitches in the synapse_event_persisted_position metric ([\#3658](https://github.com/matrix-org/synapse/issues/3658))
+- Fix bug on deleting 3pid when using identity servers that don't support unbind API ([\#3661](https://github.com/matrix-org/synapse/issues/3661))
+- Make the tests pass on Twisted < 18.7.0 ([\#3676](https://github.com/matrix-org/synapse/issues/3676))
+- Don’t ship recaptcha_ajax.js, use it directly from Google ([\#3677](https://github.com/matrix-org/synapse/issues/3677))
+- Fixes test_reap_monthly_active_users so it passes under postgres ([\#3681](https://github.com/matrix-org/synapse/issues/3681))
+- Fix mau blocking calulation bug on login ([\#3689](https://github.com/matrix-org/synapse/issues/3689))
+- Fix missing yield in synapse.storage.monthly_active_users.initialise_reserved_users ([\#3692](https://github.com/matrix-org/synapse/issues/3692))
+- Improve HTTP request logging to include all requests ([\#3700](https://github.com/matrix-org/synapse/issues/3700))
+- Avoid timing out requests while we are streaming back the response ([\#3701](https://github.com/matrix-org/synapse/issues/3701))
+- Support more federation endpoints on workers ([\#3705](https://github.com/matrix-org/synapse/issues/3705), [\#3713](https://github.com/matrix-org/synapse/issues/3713))
+- Fix "Starting db txn 'get_all_updated_receipts' from sentinel context" warning ([\#3710](https://github.com/matrix-org/synapse/issues/3710))
+- Fix bug where `state_cache` cache factor ignored environment variables ([\#3719](https://github.com/matrix-org/synapse/issues/3719))
+
+
+Deprecations and Removals
+-------------------------
+
+- The Shared-Secret registration method of the legacy v1/register REST endpoint has been removed. For a replacement, please see [the admin/register API documentation](https://github.com/matrix-org/synapse/blob/master/docs/admin_api/register_api.rst). ([\#3703](https://github.com/matrix-org/synapse/issues/3703))
+
+
+Internal Changes
+----------------
+
+- The test suite now can run under PostgreSQL. ([\#3423](https://github.com/matrix-org/synapse/issues/3423))
+- Refactor HTTP replication endpoints to reduce code duplication ([\#3632](https://github.com/matrix-org/synapse/issues/3632))
+- Tests now correctly execute on Python 3. ([\#3647](https://github.com/matrix-org/synapse/issues/3647))
+- Sytests can now be run inside a Docker container. ([\#3660](https://github.com/matrix-org/synapse/issues/3660))
+- Port over enough to Python 3 to allow the sytests to start. ([\#3668](https://github.com/matrix-org/synapse/issues/3668))
+- Update docker base image from alpine 3.7 to 3.8. ([\#3669](https://github.com/matrix-org/synapse/issues/3669))
+- Rename synapse.util.async to synapse.util.async_helpers to mitigate async becoming a keyword on Python 3.7. ([\#3678](https://github.com/matrix-org/synapse/issues/3678))
+- Synapse's tests are now formatted with the black autoformatter. ([\#3679](https://github.com/matrix-org/synapse/issues/3679))
+- Implemented a new testing base class to reduce test boilerplate. ([\#3684](https://github.com/matrix-org/synapse/issues/3684))
+- Rename MAU prometheus metrics ([\#3690](https://github.com/matrix-org/synapse/issues/3690))
+- add new error type ResourceLimit ([\#3707](https://github.com/matrix-org/synapse/issues/3707))
+- Logcontexts for replication command handlers ([\#3709](https://github.com/matrix-org/synapse/issues/3709))
+- Update admin register API documentation to reference a real user ID. ([\#3712](https://github.com/matrix-org/synapse/issues/3712))
+
+
 Synapse 0.33.2 (2018-08-09)
 ===========================
 

changelog.d/1491.feature

@@ -1 +0,0 @@
-Add support for the SNI extension to federation TLS connections

changelog.d/3184.feature

@@ -1 +0,0 @@
-Add /_media/r0/config

changelog.d/3423.misc

@@ -1 +0,0 @@
-The test suite now can run under PostgreSQL.

changelog.d/3568.feature

@@ -1 +0,0 @@
-speed up /members API and add `at` and `membership` params as per MSC1227

changelog.d/3574.feature

@@ -1 +0,0 @@
-implement `summary` block in /sync response as per MSC688

changelog.d/3589.feature

@@ -1 +0,0 @@
-Add lazy-loading support to /messages as per MSC1227

changelog.d/3632.misc

@@ -1 +0,0 @@
-Refactor HTTP replication endpoints to reduce code duplication

changelog.d/3633.feature

@@ -1 +0,0 @@
-Add ability to limit number of monthly active users on the server

changelog.d/3647.misc

@@ -1 +0,0 @@
-Tests now correctly execute on Python 3.

changelog.d/3653.feature

@@ -1 +0,0 @@
-Support more federation endpoints on workers

changelog.d/3654.feature

@@ -1 +0,0 @@
-Basic support for room versioning

changelog.d/3655.feature

@@ -1 +0,0 @@
-Ability to disable client/server Synapse via conf toggle

changelog.d/3658.bugfix

@@ -1 +0,0 @@
-Fix occasional glitches in the synapse_event_persisted_position metric

changelog.d/3660.misc

@@ -1 +0,0 @@
-Sytests can now be run inside a Docker container.

changelog.d/3661.bugfix

@@ -1 +0,0 @@
-Fix bug on deleting 3pid when using identity servers that don't support unbind API

changelog.d/3662.feature

@@ -1 +0,0 @@
-Ability to whitelist specific threepids against monthly active user limiting

changelog.d/3664.feature

@@ -1 +0,0 @@
-Add some metrics for the appservice and federation event sending loops

changelog.d/3669.misc

@@ -1 +0,0 @@
-Update docker base image from alpine 3.7 to 3.8.

changelog.d/3670.feature

@@ -1 +0,0 @@
-Where server is disabled, block ability for locked out users to read new messages

changelog.d/3676.bugfix

@@ -1 +0,0 @@
-Make the tests pass on Twisted < 18.7.0

changelog.d/3677.bugfix

@@ -1 +0,0 @@
-Don’t ship recaptcha_ajax.js, use it directly from Google

changelog.d/3678.misc

@@ -1 +0,0 @@
-Rename synapse.util.async to synapse.util.async_helpers to mitigate async becoming a keyword on Python 3.7.

changelog.d/3679.misc

@@ -1 +0,0 @@
-Synapse's tests are now formatted with the black autoformatter.

changelog.d/3681.bugfix

@@ -1 +0,0 @@
-Fixes test_reap_monthly_active_users so it passes under postgres

changelog.d/3684.misc

@@ -1 +0,0 @@
-Implemented a new testing base class to reduce test boilerplate.

changelog.d/3687.feature

@@ -1 +0,0 @@
-set admin uri via config, to be used in error messages where the user should contact the administrator

changelog.d/3689.bugfix

@@ -1 +0,0 @@
-Fix mau blocking calulation bug on login

changelog.d/3690.misc

@@ -1 +0,0 @@
-Rename MAU prometheus metrics

changelog.d/3692.bugfix

@@ -1 +0,0 @@
-Fix missing yield in synapse.storage.monthly_active_users.initialise_reserved_users

changelog.d/3694.feature

@@ -1 +0,0 @@
-Synapse's presence functionality can now be disabled with the "use_presence" configuration option.

changelog.d/3700.bugfix

@@ -1 +0,0 @@
-Improve HTTP request logging to include all requests

changelog.d/3701.bugfix

@@ -1 +0,0 @@
-Avoid timing out requests while we are streaming back the response

changelog.d/3703.removal

@@ -1 +0,0 @@
-The Shared-Secret registration method of the legacy v1/register REST endpoint has been removed. For a replacement, please see [the admin/register API documentation](https://github.com/matrix-org/synapse/blob/master/docs/admin_api/register_api.rst).

changelog.d/3705.bugfix

@@ -1 +0,0 @@
-Support more federation endpoints on workers

changelog.d/3707.misc

@@ -1 +0,0 @@
-add new error type ResourceLimit

changelog.d/3708.feature

@@ -1 +0,0 @@
-For resource limit blocked users, prevent writing into rooms

changelog.d/3709.misc

@@ -1 +0,0 @@
-Logcontexts for replication command handlers

changelog.d/3710.bugfix

@@ -1 +0,0 @@
-Fix "Starting db txn 'get_all_updated_receipts' from sentinel context" warning

changelog.d/3712.misc

@@ -1 +0,0 @@
-Update admin register API documentation to reference a real user ID.

changelog.d/3713.bugfix

@@ -1 +0,0 @@
-Support more federation endpoints on workers

changelog.d/3719.bugfix

@@ -1 +0,0 @@
-Fix bug where `state_cache` cache factor ignored environment variables

synapse/__init__.py

@@ -17,4 +17,4 @@
 """ This is a reference implementation of a Matrix home server.
 """
 
-__version__ = "0.33.2"
+__version__ = "0.33.3rc2"

synapse/api/auth.py

@@ -211,7 +211,7 @@ class Auth(object):
             user_agent = request.requestHeaders.getRawHeaders(
                 b"User-Agent",
                 default=[b""]
-            )[0]
+            )[0].decode('ascii', 'surrogateescape')
             if user and access_token and ip_addr:
                 yield self.store.insert_client_ip(
                     user_id=user.to_string(),
@@ -682,7 +682,7 @@ class Auth(object):
         Returns:
             bool: False if no access_token was given, True otherwise.
         """
-        query_params = request.args.get("access_token")
+        query_params = request.args.get(b"access_token")
         auth_headers = request.requestHeaders.getRawHeaders(b"Authorization")
         return bool(query_params) or bool(auth_headers)
 
@@ -698,7 +698,7 @@ class Auth(object):
                 401 since some of the old clients depended on auth errors returning
                 403.
         Returns:
-            str: The access_token
+            unicode: The access_token
         Raises:
             AuthError: If there isn't an access_token in the request.
         """
@@ -720,9 +720,9 @@ class Auth(object):
                     "Too many Authorization headers.",
                     errcode=Codes.MISSING_TOKEN,
                 )
-            parts = auth_headers[0].split(" ")
+            parts = auth_headers[0].split(b" ")
-            if parts[0] == "Bearer" and len(parts) == 2:
+            if parts[0] == b"Bearer" and len(parts) == 2:
-                return parts[1]
+                return parts[1].decode('ascii')
             else:
                 raise AuthError(
                     token_not_found_http_status,
@@ -738,7 +738,7 @@ class Auth(object):
                     errcode=Codes.MISSING_TOKEN
                 )
 
-            return query_params[0]
+            return query_params[0].decode('ascii')
 
     @defer.inlineCallbacks
     def check_in_room_or_world_readable(self, room_id, user_id):

synapse/api/ratelimiting.py

@@ -72,7 +72,7 @@ class Ratelimiter(object):
         return allowed, time_allowed
 
     def prune_message_counts(self, time_now_s):
-        for user_id in self.message_counts.keys():
+        for user_id in list(self.message_counts.keys()):
             message_count, time_start, msg_rate_hz = (
                 self.message_counts[user_id]
             )

synapse/config/logger.py

@@ -168,7 +168,8 @@ def setup_logging(config, use_worker_options=False):
         if log_file:
             # TODO: Customisable file size / backup count
             handler = logging.handlers.RotatingFileHandler(
-                log_file, maxBytes=(1000 * 1000 * 100), backupCount=3
+                log_file, maxBytes=(1000 * 1000 * 100), backupCount=3,
+                encoding='utf8'
             )
 
             def sighup(signum, stack):

synapse/http/servlet.py

@@ -29,7 +29,7 @@ def parse_integer(request, name, default=None, required=False):
 
     Args:
         request: the twisted HTTP request.
-        name (str): the name of the query parameter.
+        name (bytes/unicode): the name of the query parameter.
         default (int|None): value to use if the parameter is absent, defaults
             to None.
         required (bool): whether to raise a 400 SynapseError if the
@@ -46,6 +46,10 @@ def parse_integer(request, name, default=None, required=False):
 
 
 def parse_integer_from_args(args, name, default=None, required=False):
+
+    if not isinstance(name, bytes):
+        name = name.encode('ascii')
+
     if name in args:
         try:
             return int(args[name][0])
@@ -65,7 +69,7 @@ def parse_boolean(request, name, default=None, required=False):
 
     Args:
         request: the twisted HTTP request.
-        name (str): the name of the query parameter.
+        name (bytes/unicode): the name of the query parameter.
         default (bool|None): value to use if the parameter is absent, defaults
             to None.
         required (bool): whether to raise a 400 SynapseError if the
@@ -83,11 +87,15 @@ def parse_boolean(request, name, default=None, required=False):
 
 
 def parse_boolean_from_args(args, name, default=None, required=False):
+
+    if not isinstance(name, bytes):
+        name = name.encode('ascii')
+
     if name in args:
         try:
             return {
-                "true": True,
+                b"true": True,
-                "false": False,
+                b"false": False,
             }[args[name][0]]
         except Exception:
             message = (
@@ -104,21 +112,29 @@ def parse_boolean_from_args(args, name, default=None, required=False):
 
 
 def parse_string(request, name, default=None, required=False,
-                 allowed_values=None, param_type="string"):
+                 allowed_values=None, param_type="string", encoding='ascii'):
-    """Parse a string parameter from the request query string.
+    """
+    Parse a string parameter from the request query string.
+
+    If encoding is not None, the content of the query param will be
+    decoded to Unicode using the encoding, otherwise it will be encoded
 
     Args:
         request: the twisted HTTP request.
-        name (str): the name of the query parameter.
+        name (bytes/unicode): the name of the query parameter.
-        default (str|None): value to use if the parameter is absent, defaults
+        default (bytes/unicode|None): value to use if the parameter is absent,
-            to None.
+            defaults to None. Must be bytes if encoding is None.
         required (bool): whether to raise a 400 SynapseError if the
             parameter is absent, defaults to False.
-        allowed_values (list[str]): List of allowed values for the string,
+        allowed_values (list[bytes/unicode]): List of allowed values for the
-            or None if any value is allowed, defaults to None
+            string, or None if any value is allowed, defaults to None. Must be
+            the same type as name, if given.
+        encoding: The encoding to decode the name to, and decode the string
+            content with.
 
     Returns:
-        str|None: A string value or the default.
+        bytes/unicode|None: A string value or the default. Unicode if encoding
+        was given, bytes otherwise.
 
     Raises:
         SynapseError if the parameter is absent and required, or if the
@@ -126,14 +142,22 @@ def parse_string(request, name, default=None, required=False,
             is not one of those allowed values.
     """
     return parse_string_from_args(
-        request.args, name, default, required, allowed_values, param_type,
+        request.args, name, default, required, allowed_values, param_type, encoding
     )
 
 
 def parse_string_from_args(args, name, default=None, required=False,
-                           allowed_values=None, param_type="string"):
+                           allowed_values=None, param_type="string", encoding='ascii'):
+
+    if not isinstance(name, bytes):
+        name = name.encode('ascii')
+
     if name in args:
         value = args[name][0]
+
+        if encoding:
+            value = value.decode(encoding)
+
         if allowed_values is not None and value not in allowed_values:
             message = "Query parameter %r must be one of [%s]" % (
                 name, ", ".join(repr(v) for v in allowed_values)
@@ -146,6 +170,10 @@ def parse_string_from_args(args, name, default=None, required=False,
             message = "Missing %s query parameter %r" % (param_type, name)
             raise SynapseError(400, message, errcode=Codes.MISSING_PARAM)
         else:
+
+            if encoding and isinstance(default, bytes):
+                return default.decode(encoding)
+
             return default
 
 

synapse/http/site.py

@@ -182,7 +182,7 @@ class SynapseRequest(Request):
         # the client disconnects.
         with PreserveLoggingContext(self.logcontext):
             logger.warn(
-                "Error processing request: %s %s", reason.type, reason.value,
+                "Error processing request %r: %s %s", self, reason.type, reason.value,
             )
 
             if not self._is_processing:
@@ -219,6 +219,12 @@ class SynapseRequest(Request):
         """Log the completion of this request and update the metrics
         """
 
+        if self.logcontext is None:
+            # this can happen if the connection closed before we read the
+            # headers (so render was never called). In that case we'll already
+            # have logged a warning, so just bail out.
+            return
+
         usage = self.logcontext.get_resource_usage()
 
         if self._processing_finished_time is None:
@@ -235,7 +241,7 @@ class SynapseRequest(Request):
         # need to decode as it could be raw utf-8 bytes
         # from a IDN servname in an auth header
         authenticated_entity = self.authenticated_entity
-        if authenticated_entity is not None:
+        if authenticated_entity is not None and isinstance(authenticated_entity, bytes):
             authenticated_entity = authenticated_entity.decode("utf-8", "replace")
 
         # ...or could be raw utf-8 bytes in the User-Agent header.
@@ -328,7 +334,7 @@ class SynapseSite(Site):
         proxied = config.get("x_forwarded", False)
         self.requestFactory = SynapseRequestFactory(self, proxied)
         self.access_logger = logging.getLogger(logger_name)
-        self.server_version_string = server_version_string
+        self.server_version_string = server_version_string.encode('ascii')
 
     def log(self, request):
         pass

synapse/rest/client/transactions.py

@@ -53,7 +53,7 @@ class HttpTransactionCache(object):
             str: A transaction key
         """
         token = self.auth.get_access_token_from_request(request)
-        return request.path + "/" + token
+        return request.path.decode('utf8') + "/" + token
 
     def fetch_or_execute_request(self, request, fn, *args, **kwargs):
         """A helper function for fetch_or_execute which extracts

synapse/rest/media/v1/upload_resource.py

@@ -55,7 +55,7 @@ class UploadResource(Resource):
         requester = yield self.auth.get_user_by_req(request)
         # TODO: The checks here are a bit late. The content will have
         # already been uploaded to a tmp file at this point
-        content_length = request.getHeader("Content-Length")
+        content_length = request.getHeader(b"Content-Length").decode('ascii')
         if content_length is None:
             raise SynapseError(
                 msg="Request must specify a Content-Length", code=400
@@ -66,10 +66,10 @@ class UploadResource(Resource):
                 code=413,
             )
 
-        upload_name = parse_string(request, "filename")
+        upload_name = parse_string(request, b"filename", encoding=None)
         if upload_name:
             try:
-                upload_name = upload_name.decode('UTF-8')
+                upload_name = upload_name.decode('utf8')
             except UnicodeDecodeError:
                 raise SynapseError(
                     msg="Invalid UTF-8 filename parameter: %r" % (upload_name),
@@ -78,8 +78,8 @@ class UploadResource(Resource):
 
         headers = request.requestHeaders
 
-        if headers.hasHeader("Content-Type"):
+        if headers.hasHeader(b"Content-Type"):
-            media_type = headers.getRawHeaders(b"Content-Type")[0]
+            media_type = headers.getRawHeaders(b"Content-Type")[0].decode('ascii')
         else:
             raise SynapseError(
                 msg="Upload request missing 'Content-Type'",

synapse/secrets.py

@@ -38,4 +38,4 @@ else:
             return os.urandom(nbytes)
 
         def token_hex(self, nbytes=32):
-            return binascii.hexlify(self.token_bytes(nbytes))
+            return binascii.hexlify(self.token_bytes(nbytes)).decode('ascii')

synapse/util/logcontext.py

@@ -385,7 +385,13 @@ class LoggingContextFilter(logging.Filter):
         context = LoggingContext.current_context()
         for key, value in self.defaults.items():
             setattr(record, key, value)
+
+        # context should never be None, but if it somehow ends up being, then
+        # we end up in a death spiral of infinite loops, so let's check, for
+        # robustness' sake.
+        if context is not None:
             context.copy_to(record)
+
         return True
 
 
@@ -396,7 +402,9 @@ class PreserveLoggingContext(object):
 
     __slots__ = ["current_context", "new_context", "has_parent"]
 
-    def __init__(self, new_context=LoggingContext.sentinel):
+    def __init__(self, new_context=None):
+        if new_context is None:
+            new_context = LoggingContext.sentinel
         self.new_context = new_context
 
     def __enter__(self):

synapse/util/logutils.py

@@ -20,6 +20,8 @@ import time
 from functools import wraps
 from inspect import getcallargs
 
+from six import PY3
+
 _TIME_FUNC_ID = 0
 
 
@@ -28,6 +30,10 @@ def _log_debug_as_f(f, msg, msg_args):
     logger = logging.getLogger(name)
 
     if logger.isEnabledFor(logging.DEBUG):
+        if PY3:
+            lineno = f.__code__.co_firstlineno
+            pathname = f.__code__.co_filename
+        else:
             lineno = f.func_code.co_firstlineno
             pathname = f.func_code.co_filename
 

synapse/util/stringutils.py

@@ -16,6 +16,7 @@
 import random
 import string
 
+from six import PY3
 from six.moves import range
 
 _string_with_symbols = (
@@ -34,6 +35,17 @@ def random_string_with_symbols(length):
 
 
 def is_ascii(s):
+
+    if PY3:
+        if isinstance(s, bytes):
+            try:
+                s.decode('ascii').encode('ascii')
+            except UnicodeDecodeError:
+                return False
+            except UnicodeEncodeError:
+                return False
+            return True
+
     try:
         s.encode("ascii")
     except UnicodeEncodeError:
@@ -49,6 +61,9 @@ def to_ascii(s):
 
     If given None then will return None.
     """
+    if PY3:
+        return s
+
     if s is None:
         return None
 

synapse/util/versionstring.py

@@ -30,7 +30,7 @@ def get_version_string(module):
                 ['git', 'rev-parse', '--abbrev-ref', 'HEAD'],
                 stderr=null,
                 cwd=cwd,
-            ).strip()
+            ).strip().decode('ascii')
             git_branch = "b=" + git_branch
         except subprocess.CalledProcessError:
             git_branch = ""
@@ -40,7 +40,7 @@ def get_version_string(module):
                 ['git', 'describe', '--exact-match'],
                 stderr=null,
                 cwd=cwd,
-            ).strip()
+            ).strip().decode('ascii')
             git_tag = "t=" + git_tag
         except subprocess.CalledProcessError:
             git_tag = ""
@@ -50,7 +50,7 @@ def get_version_string(module):
                 ['git', 'rev-parse', '--short', 'HEAD'],
                 stderr=null,
                 cwd=cwd,
-            ).strip()
+            ).strip().decode('ascii')
         except subprocess.CalledProcessError:
             git_commit = ""
 
@@ -60,7 +60,7 @@ def get_version_string(module):
                 ['git', 'describe', '--dirty=' + dirty_string],
                 stderr=null,
                 cwd=cwd,
-            ).strip().endswith(dirty_string)
+            ).strip().decode('ascii').endswith(dirty_string)
 
             git_dirty = "dirty" if is_dirty else ""
         except subprocess.CalledProcessError:
@@ -77,8 +77,8 @@ def get_version_string(module):
                 "%s (%s)" % (
                     module.__version__, git_version,
                 )
-            ).encode("ascii")
+            )
     except Exception as e:
         logger.info("Failed to check for git repository: %s", e)
 
-    return module.__version__.encode("ascii")
+    return module.__version__