Ship the email templates as package_data

MANIFEST.in

@@ -12,12 +12,12 @@ recursive-include synapse/storage/schema *.sql
 recursive-include synapse/storage/schema *.py
 
 recursive-include docs *
-recursive-include res *
 recursive-include scripts *
 recursive-include scripts-dev *
 recursive-include synapse *.pyi
 recursive-include tests *.py
 
+recursive-include synapse/res *
 recursive-include synapse/static *.css
 recursive-include synapse/static *.gif
 recursive-include synapse/static *.html

changelog.d/4052.feature

@@ -0,0 +1,12 @@
+Ship the example email templates as part of the package
+
+**Note**: if you deploy your Synapse instance from a git checkout or a github
+snapshot URL, then this means that the example email templates will no longer
+be installed in `res/templates`. If you have email notifications enabled, you
+should ensure that `email.template_dir` is either configured to point at a
+directory where you have installed customised templates, or leave it unset to
+use the default templates.
+
+The configuration parser will try to detect the situation where
+`email.template_dir` is incorrectly set to `res/templates` and do the right
+thing, but will warn about this.

docker/conf/homeserver.yaml

@@ -211,7 +211,9 @@ email:
    require_transport_security: False
    notif_from: "{{ SYNAPSE_SMTP_FROM or "hostmaster@" + SYNAPSE_SERVER_NAME }}"
    app_name: Matrix
-   template_dir: res/templates
+   # if template_dir is unset, uses the example templates that are part of
+   # the Synapse distribution.
+   #template_dir: res/templates
    notif_template_html: notif_mail.html
    notif_template_text: notif_mail.txt
    notif_for_new_users: True

synapse/config/emailconfig.py

@@ -13,11 +13,19 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
+
 # This file can't be called email.py because if it is, we cannot:
 import email.utils
+import logging
+import os
+import sys
+import textwrap
 
 from ._base import Config
 
+logger = logging.getLogger(__name__)
+
 
 class EmailConfig(Config):
     def read_config(self, config):
@@ -38,7 +46,6 @@ def read_config(self, config):
                 "smtp_host",
                 "smtp_port",
                 "notif_from",
-                "template_dir",
                 "notif_template_html",
                 "notif_template_text",
             ]
@@ -62,9 +69,27 @@ def read_config(self, config):
             self.email_smtp_host = email_config["smtp_host"]
             self.email_smtp_port = email_config["smtp_port"]
             self.email_notif_from = email_config["notif_from"]
-            self.email_template_dir = email_config["template_dir"]
             self.email_notif_template_html = email_config["notif_template_html"]
             self.email_notif_template_text = email_config["notif_template_text"]
+
+            self.email_template_dir = email_config.get("template_dir")
+
+            # backwards-compatibility hack
+            if (
+                self.email_template_dir == "res/templates"
+                and not os.path.isfile(
+                    os.path.join(self.email_template_dir, self.email_notif_template_text)
+                )
+            ):
+                t = """\
+WARNING: The email notifier is configured to look for templates in '%s', but no templates
+could be found there. We will fall back to using the example templates; to get rid of this
+warning, leave 'email.template_dir' unset.
+""" % (self.email_template_dir,)
+
+                print(textwrap.fill(t, width=80) + "\n", file=sys.stderr)
+                self.email_template_dir = None
+
             self.email_notif_for_new_users = email_config.get(
                 "notif_for_new_users", True
             )
@@ -113,7 +138,9 @@ def default_config(self, config_dir_path, server_name, **kwargs):
         #   require_transport_security: False
         #   notif_from: "Your Friendly %(app)s Home Server <[email protected]>"
         #   app_name: Matrix
-        #   template_dir: res/templates
+        #   # if template_dir is unset, uses the example templates that are part of
+        #   # the Synapse distribution.
+        #   #template_dir: res/templates
         #   notif_template_html: notif_mail.html
         #   notif_template_text: notif_mail.txt
         #   notif_for_new_users: True

synapse/push/mailer.py

@@ -528,7 +528,10 @@ def load_jinja2_templates(config):
     """
     logger.info("loading jinja2")
 
-    loader = jinja2.FileSystemLoader(config.email_template_dir)
+    if config.email_template_dir:
+        loader = jinja2.FileSystemLoader(config.email_template_dir)
+    else:
+        loader = jinja2.PackageLoader('synapse', 'res/templates')
     env = jinja2.Environment(loader=loader)
     env.filters["format_ts"] = format_ts_filter
     env.filters["mxc_to_http"] = _create_mxc_to_http_filter(config)