Allow specification of domain block list inline

README.md

@@ -48,10 +48,16 @@ Currently the following options are supported:
    attribute mapped to `uid` to identify the remote user instead of the `NameID`
    from the assertion. `True` by default.
 
- * `domain_block_file`: should point a file containing a list of domains (one
+ * `bad_domain_file`: should point a file containing a list of domains (one
    per line); users who have an email address on any of these domains will be
    blocked from registration.
 
+ * `bad_domain_list`: an alternative to `bad_domain_file` allowing the list of
+   bad domains to be specified inline in the config.
+
+   If both `bad_domain_file` and `bad_domain_list` are specified, the two lists
+   are merged.
+
 ## Implementation notes
 
 The login flow looks something like this:

matrix_synapse_saml_mozilla/mapping_provider.py

@@ -41,7 +41,7 @@ MAPPING_SESSION_VALIDITY_PERIOD_MS = 15 * 60 * 1000
 @attr.s
 class SamlConfig(object):
     use_name_id_for_remote_uid = attr.ib(type=bool, default=True)
-    domain_block_list = attr.ib(type=Set[str], default={})
+    domain_block_list = attr.ib(type=Set[str], factory=set)
 
 
 class SamlMappingProvider(object):
@@ -158,13 +158,15 @@ class SamlMappingProvider(object):
         if "use_name_id_for_remote_uid" in config:
             parsed.use_name_id_for_remote_uid = config["use_name_id_for_remote_uid"]
 
-        domain_block_file = config.get("domain_block_file")
+        parsed.domain_block_list.update(config.get("bad_domain_list", []))
+
+        domain_block_file = config.get("bad_domain_file")
         if domain_block_file:
             try:
                 with open(domain_block_file, encoding="ascii") as fh:
-                    parsed.domain_block_list = {
+                    parsed.domain_block_list.update(
                         line.strip().lower() for line in fh.readlines()
-                    }
+                    )
             except Exception as e:
                 raise Exception(
                     "Error reading domain block file %s: %s" % (domain_block_file, e)