treewide: add support for unix sockets

synapse-module/default.nix

@@ -10,7 +10,9 @@ let
   wcfgText = "config.services.matrix-synapse-next.workers";
 
   format = pkgs.formats.yaml {};
-  matrix-synapse-common-config = format.generate "matrix-synapse-common-config.yaml" cfg.settings;
+  matrix-synapse-common-config = format.generate "matrix-synapse-common-config.yaml" (cfg.settings // {
+    listeners = map (lib.filterAttrsRecursive (_: v: v != null)) cfg.settings.listeners;
+  });
 
   # TODO: Align better with the upstream module
   wrapped = cfg.package.override { 
@@ -79,6 +81,15 @@ in
       '';
     };
 
+    socketDir = mkOption {
+      type = types.path;
+      default = "/run/matrix-synapse";
+      description = ''
+        The directory where matrix-synapse by default stores the sockets of
+        all listeners that bind to UNIX sockets.
+      '';
+    };
+
     enableNginx = mkEnableOption "The synapse module managing nginx";
 
     public_baseurl = mkOption {
@@ -135,14 +146,42 @@ in
             type = types.listOf (types.submodule {
               options = {
                 port = mkOption {
-                  type = types.port;
+                  type = with types; nullOr types.port;
-                  description = "The TCP port to bind to";
+                  default = null;
+                  description = ''
+                    The TCP port to bind to.
+
+                    ::: {.note}
+                      This option will be ignored if {option}`path` is set to a non-null value.
+                    :::
+                  '';
                   example = 8448;
                 };
 
+                path = mkOption {
+                  type = with types; nullOr path;
+                  default = null;
+                  description = ''
+                    The UNIX socket to bind to.
+
+                    ::: {.note}
+                      This option will override {option}`bind_addresses` and {option}`port`
+                      if set to a non-null value.
+                    :::
+                  '';
+                  example = literalExpression ''''${${cfgText}.socketDir}/matrix-synapse.sock'';
+                };
+
                 bind_addresses = mkOption {
                   type = types.listOf types.str;
-                  description = "A list of local addresses to listen on";
+                  default = [ ];
+                  description = ''
+                    A list of local addresses to listen on.
+
+                    ::: {.note}
+                      This option will be ignored if {option}`path` is set to a non-null value.
+                    :::
+                  '';
                 };
 
                 type = mkOption {
@@ -201,16 +240,14 @@ in
             # TODO: add defaultText
             default = [
               {
-                port = 8008;
+                path = "${cfg.socketDir}/matrix-synapse.sock";
-                bind_addresses = [ "127.0.0.1" ];
                 resources = [
                   { names = [ "client" ]; compress = true; }
                   { names = [ "federation" ]; compress = false; }
                 ];
               }
               (mkIf (wcfg.instances != { }) {
-                port = 9093;
+                path = "${cfg.socketDir}/matrix-synapse-replication.sock";
-                bind_addresses = [ "127.0.0.1" ];
                 resources = [
                   {  names = [ "replication" ]; }
                 ];
@@ -352,6 +389,12 @@ in
   };
 
   config = mkIf cfg.enable {
+    assertions = [ ]
+      ++ (map (l: {
+        assertion = l.path == null -> (l.bind_addresses != [ ] && l.port != null);
+        message = "Some listeners are missing either a socket path or a bind_address + port to listen on";
+      }) cfg.settings.listeners);
+
     users.users.matrix-synapse = {
       group = "matrix-synapse";
       home = cfg.dataDir;
@@ -396,6 +439,8 @@ in
           Group = "matrix-synapse";
           Slice = "system-matrix-synapse.slice";
           WorkingDirectory = cfg.dataDir;
+          StateDirectory = "matrix-synapse";
+          RuntimeDirectory = "matrix-synapse";
           ExecStart = let
             flags = lib.cli.toGNUCommandLineShell {} {
               config-path = [ matrix-synapse-common-config ] ++ cfg.extraConfigFiles;

synapse-module/nginx.nix

@@ -40,7 +40,9 @@ let
     # Convert listeners to upstream URIs
     (lib.mapAttrs (_: listeners: lib.pipe listeners [
       (lib.concatMap (listener:
-        (map (addr: "${addr}:${toString listener.port}") listener.bind_addresses)
+        if listener.path != null
+          then [ "unix:${listener.path}" ]
+          else (map (addr: "${addr}:${toString listener.port}") listener.bind_addresses)
       ))
       (uris: lib.genAttrs uris (_: { }))
     ]))

synapse-module/workers.nix

@@ -86,10 +86,17 @@ in {
         };
 
         port = mkOption {
-          type = types.port;
+          type = with types; nullOr port;
+          default = null;
           description = "The TCP port to bind to";
         };
 
+        path = mkOption {
+          type = with types; nullOr path;
+          default = null;
+          description = "The UNIX socket to bind to";
+        };
+
         bind_addresses = mkOption {
           type = with types; listOf str;
           description = "A list of local addresses to listen on";
@@ -161,7 +168,7 @@ in {
     };
   in {
     mainReplicationHost = mkOption {
-      type = types.str;
+      type = with types; nullOr str;
       default = let
         host = (matrix-lib.connectionInfo mainReplicationListener).host;
       in
@@ -174,18 +181,32 @@ in {
     };
 
     mainReplicationPort = mkOption {
-      type = types.port;
+      type = with types; nullOr port;
       default = mainReplicationListener.port;
       # TODO: add defaultText
       description = "Port for the main synapse instance's replication listener";
     };
 
+    mainReplicationPath = mkOption {
+      type = with types; nullOr path;
+      default = mainReplicationListener.path;
+      # TODO: add defaultText
+      description = "Path to the UNIX socket of the main synapse instance's replication listener";
+    };
+
     defaultListenerAddress = mkOption {
       type = types.str;
       default = "127.0.0.1";
       description = "The default listener address for the worker";
     };
 
+    workersUsePath = mkOption {
+      type = types.bool;
+      description = "Whether to enable UNIX sockets for all automatically generated workers";
+      default = true;
+      example = false;
+    };
+
     workerStartingPort = mkOption {
       type = types.port;
       description = "What port should the automatically configured workers start enumerating from";
@@ -233,22 +254,32 @@ in {
   };
 
   config = {
+    assertions = [ ]
+      ++ (lib.concatMap (worker:
+        (map (l: {
+          assertion = l.path == null -> (l.bind_addresses != [ ] && l.port != null);
+          message = "At least one worker listener is missing either a socket path or a bind_address + port to listen on";
+        }) worker.settings.worker_listeners)
+      ) (lib.attrValues wcfg.instances));
+
     services.matrix-synapse-next.settings = {
       federation_sender_instances =
         lib.genList (i: "auto-fed-sender${toString (i + 1)}") wcfg.federationSenders;
 
       instance_map = (lib.mkIf (cfg.workers.instances != { }) ({
-        main = let
+        main = if wcfg.mainReplicationPath != null then {
-          host = lib.head mainReplicationListener.bind_addresses;
+          path = wcfg.mainReplicationPath;
-        in {
+        } else {
-          host = if builtins.elem host [ "0.0.0.0" "::"] then "127.0.0.1" else host;
+          host = wcfg.mainReplicationHost;
-          port = mainReplicationListener.port;
+          port = wcfg.mainReplicationPort;
         };
       } // genAttrs' (lib.lists.range 1 wcfg.eventPersisters)
         (i: "auto-event-persist${toString i}")
         (i: let
           wRL = matrix-lib.firstListenerOfType "replication" wcfg.instances."auto-event-persist${toString i}".settings.worker_listeners;
-        in matrix-lib.connectionInfo wRL)));
+        in if wRL.path != null then {
+          inherit (wRL) path;
+        } else matrix-lib.connectionInfo wRL)));
 
       stream_writers.events =
         mkIf (wcfg.eventPersisters > 0)
@@ -260,10 +291,15 @@ in {
 
     services.matrix-synapse-next.workers.instances = let
       sum = lib.foldl lib.add 0;
-      workerListenersWithMetrics = portOffset:
+      workerListenersWithMetrics = portOffset: name:
-        lib.singleton ({
+        [(if wcfg.workersUsePath
-          port = wcfg.workerStartingPort + portOffset - 1;
+          then {
-        }) 
+            path = "${cfg.socketDir}/matrix-synapse-worker-${name}.sock";
+          }
+          else {
+            port = wcfg.workerStartingPort + portOffset - 1;
+          }
+        )]
         ++ lib.optional wcfg.enableMetrics {
           port = wcfg.metricsStartingPort + portOffset;
           resources = [ { names = [ "metrics" ]; } ];
@@ -274,7 +310,7 @@ in {
         numberOfWorkers,
         portOffset ? 0,
         nameFn ? i: "auto-${type}${toString i}",
-        workerListenerFn ? i: workerListenersWithMetrics (portOffset + i)
+        workerListenerFn ? i: name: workerListenersWithMetrics (portOffset + i) name
       }: genAttrs'
         (lib.lists.range 1 numberOfWorkers)
         nameFn
@@ -282,7 +318,7 @@ in {
           isAuto = true;
           inherit type;
           index = i;
-          settings.worker_listeners = workerListenerFn i;
+          settings.worker_listeners = workerListenerFn i (nameFn i);
         });
 
       workerInstances = {
@@ -323,8 +359,13 @@ in {
 
     systemd.services = let
       workerList = lib.mapAttrsToList lib.nameValuePair wcfg.instances;
-      workerConfig = worker: format.generate "matrix-synapse-worker-${worker.name}-config.yaml"
+      workerConfig = worker:
-        (worker.value.settings // { worker_name = worker.name; });
+        format.generate "matrix-synapse-worker-${worker.name}-config.yaml"
+        (worker.value.settings // {
+          worker_name = worker.name;
+          worker_listeners =
+            map (lib.filterAttrsRecursive (_: v: v != null)) worker.value.settings.worker_listeners;
+        });
     in builtins.listToAttrs (lib.flip map workerList (worker: {
       name = "matrix-synapse-worker-${worker.name}";
       value = {
@@ -339,6 +380,8 @@ in {
           Group = "matrix-synapse";
           Slice = "system-matrix-synapse.slice";
           WorkingDirectory = cfg.dataDir;
+          RuntimeDirectory = "matrix-synapse";
+          StateDirectory = "matrix-synapse";
           ExecStartPre = pkgs.writers.writeBash "wait-for-synapse" ''
             # From https://md.darmstadt.ccc.de/synapse-at-work
             while ! systemctl is-active -q matrix-synapse.service; do