Import sliding sync from nixpkgs unstable

Co-authored-by: Sandro Jäckel <sandro.jaeckel@gmail.com>
Co-authored-by: Emily <55066419+emilylange@users.noreply.github.com>

flake.nix

@@ -7,7 +7,7 @@
 
   outputs = { self, nixpkgs-lib }: {
     nixosModules = {
-      synapse = import ./synapse-module;
+      default = import ./module.nix;
     };
     lib = import ./lib.nix { lib = nixpkgs-lib.lib; };
   };

module.nix

@@ -0,0 +1,8 @@
+{ ... }:
+
+{
+  imports = [
+    ./synapse-module
+    ./sliding-sync
+  ];
+}

pkgs/matrix-sliding-sync/default.nix

@@ -0,0 +1,37 @@
+{ lib
+, buildGoModule
+, fetchFromGitHub
+}:
+
+buildGoModule rec {
+  pname = "matrix-sliding-sync";
+  version = "0.99.10";
+
+  src = fetchFromGitHub {
+    owner = "matrix-org";
+    repo = "sliding-sync";
+    rev = "refs/tags/v${version}";
+    hash = "sha256-TjChelGVicA59q6iIIDTI7nSj8KtjpA4bfZqsfoiOQg=";
+  };
+
+  vendorHash = "sha256-E3nCcw6eTKKcL55ls6n5pYlRFffsefsN0G1Hwd49uh8=";
+
+  subPackages = [ "cmd/syncv3" ];
+
+  ldflags = [
+    "-s"
+    "-w"
+    "-X main.GitCommit=${src.rev}"
+  ];
+
+  # requires a running matrix-synapse
+  doCheck = false;
+
+  meta = with lib; {
+    description = "A sliding sync implementation of MSC3575 for matrix";
+    homepage = "https://github.com/matrix-org/sliding-sync";
+    license = with licenses; [ asl20 ];
+    maintainers = with maintainers; [ emilylange ];
+    mainProgram = "syncv3";
+  };
+}

sliding-sync/default.nix

@@ -0,0 +1,102 @@
+{ config, lib, pkgs, ... }:
+
+let
+  cfg = config.services.matrix-synapse.sliding-sync;
+in
+{
+  disabledModules = [ "services/matrix/matrix-sliding-sync.nix" ];
+
+  options.services.matrix-synapse.sliding-sync = {
+    enable = lib.mkEnableOption (lib.mdDoc "sliding sync");
+
+    package = lib.mkOption {
+      type = lib.types.package;
+      default = pkgs.callPackage ../pkgs/matrix-sliding-sync { };
+      description = "What package to use for the sliding-sync proxy.";
+    };
+
+    settings = lib.mkOption {
+      type = lib.types.submodule {
+        freeformType = with lib.types; attrsOf str;
+        options = {
+          SYNCV3_SERVER = lib.mkOption {
+            type = lib.types.str;
+            description = lib.mdDoc ''
+              The destination homeserver to talk to not including `/_matrix/` e.g `https://matrix.example.org`.
+            '';
+          };
+
+          SYNCV3_DB = lib.mkOption {
+            type = lib.types.str;
+            default = "postgresql:///matrix-sliding-sync?host=/run/postgresql";
+            description = lib.mdDoc ''
+              The postgres connection string.
+              Refer to <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING>.
+            '';
+          };
+
+          SYNCV3_BINDADDR = lib.mkOption {
+            type = lib.types.str;
+            default = "127.0.0.1:8009";
+            example = "[::]:8008";
+            description = lib.mdDoc "The interface and port to listen on.";
+          };
+
+          SYNCV3_LOG_LEVEL = lib.mkOption {
+            type = lib.types.enum [ "trace" "debug" "info" "warn" "error" "fatal" ];
+            default = "info";
+            description = lib.mdDoc "The level of verbosity for messages logged.";
+          };
+        };
+      };
+      default = { };
+      description = ''
+        Freeform environment variables passed to the sliding sync proxy.
+        Refer to <https://github.com/matrix-org/sliding-sync#setup> for all supported values.
+      '';
+    };
+
+    createDatabase = lib.mkOption {
+      type = lib.types.bool;
+      default = true;
+      description = lib.mdDoc ''
+        Whether to enable and configure `services.postgres` to ensure that the database user `matrix-sliding-sync`
+        and the database `matrix-sliding-sync` exist.
+      '';
+    };
+
+    environmentFile = lib.mkOption {
+      type = lib.types.str;
+      description = lib.mdDoc ''
+        Environment file as defined in {manpage}`systemd.exec(5)`.
+
+        This must contain the {env}`SYNCV3_SECRET` variable which should
+        be generated with {command}`openssl rand -hex 32`.
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    services.postgresql = lib.optionalAttrs cfg.createDatabase {
+      enable = true;
+      ensureDatabases = [ "matrix-sliding-sync" ];
+      ensureUsers = [ rec {
+        name = "matrix-sliding-sync";
+        ensurePermissions."DATABASE \"${name}\"" = "ALL PRIVILEGES";
+      } ];
+    };
+
+    systemd.services.matrix-sliding-sync = {
+      after = lib.optional cfg.createDatabase "postgresql.service";
+      wantedBy = [ "multi-user.target" ];
+      environment = cfg.settings;
+      serviceConfig = {
+        DynamicUser = true;
+        EnvironmentFile = cfg.environmentFile;
+        ExecStart = lib.getExe cfg.package;
+        StateDirectory = "matrix-sliding-sync";
+        WorkingDirectory = "%S/matrix-sliding-sync";
+      };
+    };
+  };
+}