feat: add support for configuring MRF

This commit adds support for allowing instances
owners/admins to configure the simple
Message Rewrite Facility (MRF) policy with their
ansible-playbook configuration. With this they can
reject/restrict messages from a list of specified
instances.

Further documentation:
https://docs.pleroma.social/mrf.html#content

This resolves dananglin/pleroma-ansible-playbook#4

roles/init/defaults/main.yml

@@ -14,6 +14,13 @@ pleroma_defaults:
     remotePostRetentionDays: 90
     logLevel: info
     federating: "true"
+    mrf:
+      simplePolicy:
+        reject: []
+        federatedTimelineRemoval: []
+        mediaRemoval: []
+        mediaNsfw: []
+        reportRemoval: []
     frontend:
       background: ""
       themes:

roles/pleroma-backend/templates/etc_pleroma_config.exs.j2

@@ -24,7 +24,8 @@ config :pleroma, :instance,
   healthcheck: {{ pleroma.config.healthCheck }},
   remote_post_retention_days: {{ pleroma.config.remotePostRetentionDays }},
   dynamic_configuration: {{ pleroma.config.dynamicConfiguration }},
-  federating: {{ pleroma.config.federating }}
+  federating: {{ pleroma.config.federating }},
+  rewrite_policy: [Pleroma.Web.ActivityPub.MRF.SimplePolicy]
 
 config :pleroma, :media_proxy,
   enabled: false,
@@ -82,3 +83,30 @@ config :pleroma, :frontend_configurations,
   {% endif %}
     theme: "{{ pleroma.config.frontend.themes.default }}"
   }
+
+config :pleroma, :mrf_simple,
+  reject: [
+  {% for item in pleroma.config.mrf.simplePolicy.reject %}
+    "{{ item }}"{{ "," if not loop.last else "" }}
+  {% endfor %}
+  ],
+  federated_timeline_removal: [
+  {% for item in pleroma.config.mrf.simplePolicy.federatedTimelineRemoval %}
+    "{{ item }}"{{ "," if not loop.last else "" }}
+  {% endfor %}
+  ],
+  media_removal: [
+  {% for item in pleroma.config.mrf.simplePolicy.mediaRemoval %}
+    "{{ item }}"{{ "," if not loop.last else "" }}
+  {% endfor %}
+  ],
+  media_nsfw: [
+  {% for item in pleroma.config.mrf.simplePolicy.mediaNsfw %}
+    "{{ item }}"{{ "," if not loop.last else "" }}
+  {% endfor %}
+  ],
+  report_removal: [
+  {% for item in pleroma.config.mrf.simplePolicy.reportRemoval %}
+    "{{ item }}"{{ "," if not loop.last else "" }}
+  {% endfor %}
+  ]