Add systemd-python to optional dependencies (#4339)

Using systemd-python allows for logging to the systemd journal,
as is documented in: `synapse/contrib/systemd/log_config.yaml`.

Signed-off-by: Silke Hofstra <silke@slxh.eu>

changelog.d/4339.feature

@@ -0,0 +1 @@
+Add systemd-python to the optional dependencies to enable logging to the systemd journal. Install with `pip install matrix-synapse[systemd]`.

docker/Dockerfile-dhvirtualenv

@@ -50,7 +50,9 @@ RUN apt-get update -qq -o Acquire::Languages=none \
         debhelper \
         devscripts \
         dh-systemd \
+        libsystemd-dev \
         lsb-release \
+        pkg-config \
         python3-dev \
         python3-pip \
         python3-setuptools \

setup.py

@@ -86,13 +86,9 @@ long_description = read_file(("README.rst",))
 
 REQUIREMENTS = dependencies['REQUIREMENTS']
 CONDITIONAL_REQUIREMENTS = dependencies['CONDITIONAL_REQUIREMENTS']
+ALL_OPTIONAL_REQUIREMENTS = dependencies['ALL_OPTIONAL_REQUIREMENTS']
 
 # Make `pip install matrix-synapse[all]` install all the optional dependencies.
-ALL_OPTIONAL_REQUIREMENTS = set()
-
-for optional_deps in CONDITIONAL_REQUIREMENTS.values():
-    ALL_OPTIONAL_REQUIREMENTS = set(optional_deps) | ALL_OPTIONAL_REQUIREMENTS
-
 CONDITIONAL_REQUIREMENTS["all"] = list(ALL_OPTIONAL_REQUIREMENTS)
 
 

synapse/python_dependencies.py

@@ -86,18 +86,22 @@ CONDITIONAL_REQUIREMENTS = {
     "acme": ["txacme>=0.9.2"],
 
     "saml2": ["pysaml2>=4.5.0"],
+    "systemd": ["systemd-python>=231"],
     "url_preview": ["lxml>=3.5.0"],
     "test": ["mock>=2.0", "parameterized"],
     "sentry": ["sentry-sdk>=0.7.2"],
 }
 
+ALL_OPTIONAL_REQUIREMENTS = set()
+
+for name, optional_deps in CONDITIONAL_REQUIREMENTS.items():
+    # Exclude systemd as it's a system-based requirement.
+    if name not in ["systemd"]:
+        ALL_OPTIONAL_REQUIREMENTS = set(optional_deps) | ALL_OPTIONAL_REQUIREMENTS
+
 
 def list_requirements():
-    deps = set(REQUIREMENTS)
-    for opt in CONDITIONAL_REQUIREMENTS.values():
-        deps = set(opt) | deps
-
-    return list(deps)
+    return list(set(REQUIREMENTS) | ALL_OPTIONAL_REQUIREMENTS)
 
 
 class DependencyException(Exception):