From b39ca49db167e814d7848c6a4872c8b65ec03ff1 Mon Sep 17 00:00:00 2001
From: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>
Date: Wed, 30 Oct 2019 11:00:15 +0000
Subject: [PATCH] Handle FileNotFound error in checking git repository version
 (#6284)

---
 changelog.d/6284.bugfix       |  1 +
 synapse/util/versionstring.py | 10 ++++++----
 2 files changed, 7 insertions(+), 4 deletions(-)
 create mode 100644 changelog.d/6284.bugfix

diff --git a/changelog.d/6284.bugfix b/changelog.d/6284.bugfix
new file mode 100644
index 000000000..cf15053d2
--- /dev/null
+++ b/changelog.d/6284.bugfix
@@ -0,0 +1 @@
+Prevent errors from appearing on Synapse startup if `git` is not installed.
\ No newline at end of file
diff --git a/synapse/util/versionstring.py b/synapse/util/versionstring.py
index fa404b9d7..ab7d03af3 100644
--- a/synapse/util/versionstring.py
+++ b/synapse/util/versionstring.py
@@ -42,6 +42,7 @@ def get_version_string(module):
     try:
         null = open(os.devnull, "w")
         cwd = os.path.dirname(os.path.abspath(module.__file__))
+
         try:
             git_branch = (
                 subprocess.check_output(
@@ -51,7 +52,8 @@ def get_version_string(module):
                 .decode("ascii")
             )
             git_branch = "b=" + git_branch
-        except subprocess.CalledProcessError:
+        except (subprocess.CalledProcessError, FileNotFoundError):
+            # FileNotFoundError can arise when git is not installed
             git_branch = ""
 
         try:
@@ -63,7 +65,7 @@ def get_version_string(module):
                 .decode("ascii")
             )
             git_tag = "t=" + git_tag
-        except subprocess.CalledProcessError:
+        except (subprocess.CalledProcessError, FileNotFoundError):
             git_tag = ""
 
         try:
@@ -74,7 +76,7 @@ def get_version_string(module):
                 .strip()
                 .decode("ascii")
             )
-        except subprocess.CalledProcessError:
+        except (subprocess.CalledProcessError, FileNotFoundError):
             git_commit = ""
 
         try:
@@ -89,7 +91,7 @@ def get_version_string(module):
             )
 
             git_dirty = "dirty" if is_dirty else ""
-        except subprocess.CalledProcessError:
+        except (subprocess.CalledProcessError, FileNotFoundError):
             git_dirty = ""
 
         if git_branch or git_tag or git_commit or git_dirty: