feat(federation): implement backfill endpoint

ee/apps/federation-service/package.json

@@ -25,7 +25,7 @@
 		"@rocket.chat/core-typings": "workspace:*",
 		"@rocket.chat/emitter": "^0.31.25",
 		"@rocket.chat/federation-matrix": "workspace:^",
-		"@rocket.chat/federation-sdk": "0.1.10",
+		"@rocket.chat/federation-sdk": "0.1.11",
 		"@rocket.chat/http-router": "workspace:*",
 		"@rocket.chat/instance-status": "workspace:^",
 		"@rocket.chat/license": "workspace:^",

ee/packages/federation-matrix/package.json

@@ -38,7 +38,7 @@
 		"@rocket.chat/core-services": "workspace:^",
 		"@rocket.chat/core-typings": "workspace:^",
 		"@rocket.chat/emitter": "^0.31.25",
-		"@rocket.chat/federation-sdk": "0.1.10",
+		"@rocket.chat/federation-sdk": "0.1.11",
 		"@rocket.chat/http-router": "workspace:^",
 		"@rocket.chat/license": "workspace:^",
 		"@rocket.chat/models": "workspace:^",

ee/packages/federation-matrix/src/api/_matrix/transactions.ts

@@ -252,6 +252,67 @@ const GetStateResponseSchema = {
 
 const isGetStateResponseProps = ajv.compile(GetStateResponseSchema);
 
+const BackfillParamsSchema = {
+	type: 'object',
+	properties: {
+		roomId: {
+			type: 'string',
+			pattern: '^![A-Za-z0-9_=\\/.+-]+:(.+)$',
+			description: 'Matrix room ID',
+		},
+	},
+	required: ['roomId'],
+	additionalProperties: false,
+};
+
+const isBackfillParamsProps = ajv.compile(BackfillParamsSchema);
+
+const BackfillQuerySchema = {
+	type: 'object',
+	properties: {
+		limit: {
+			type: 'number',
+			minimum: 1,
+			maximum: 100,
+			description: 'Maximum number of events to retrieve',
+		},
+		v: {
+			oneOf: [{ type: 'string' }, { type: 'array', items: { type: 'string' } }],
+			description: 'Event ID(s) to backfill from',
+		},
+	},
+	required: ['limit', 'v'],
+	additionalProperties: false,
+};
+
+const isBackfillQueryProps = ajv.compile<{
+	limit: number;
+	v: string | string[];
+}>(BackfillQuerySchema);
+
+const BackfillResponseSchema = {
+	type: 'object',
+	properties: {
+		origin: {
+			type: 'string',
+			description: 'Origin server',
+		},
+		origin_server_ts: {
+			type: 'number',
+			minimum: 0,
+			description: 'Unix timestamp in milliseconds',
+		},
+		pdus: {
+			type: 'array',
+			items: EventBaseSchema,
+			description: 'Events in reverse chronological order',
+		},
+	},
+	required: ['origin', 'origin_server_ts', 'pdus'],
+};
+
+const isBackfillResponseProps = ajv.compile(BackfillResponseSchema);
+
 export const getMatrixTransactionsRoutes = (services: HomeserverServices) => {
 	const { event, federationAuth } = services;
 
@@ -397,5 +458,49 @@ export const getMatrixTransactionsRoutes = (services: HomeserverServices) => {
 					};
 				},
 			)
+			// GET /_matrix/federation/v1/backfill/{roomId}
+			.get(
+				'/v1/backfill/:roomId',
+				{
+					params: isBackfillParamsProps,
+					query: isBackfillQueryProps,
+					response: {
+						200: isBackfillResponseProps,
+					},
+					tags: ['Federation'],
+					license: ['federation'],
+				},
+				async (c) => {
+					const roomId = c.req.param('roomId');
+					const limit = Number(c.req.query('limit') || 100);
+					const eventIds = c.req.queries('v');
+					if (!eventIds?.length) {
+						return {
+							body: {
+								errcode: 'M_BAD_REQUEST',
+								error: 'Event ID must be provided in v query parameter',
+							},
+							statusCode: 400,
+						};
+					}
+
+					try {
+						const result = await event.getBackfillEvents(roomId, eventIds as EventID[], limit);
+
+						return {
+							body: result,
+							statusCode: 200,
+						};
+					} catch (error) {
+						return {
+							body: {
+								errcode: 'M_UNKNOWN',
+								error: 'Failed to get backfill events',
+							},
+							statusCode: 500,
+						};
+					}
+				},
+			)
 	);
 };

yarn.lock

@@ -7543,7 +7543,7 @@ __metadata:
     "@rocket.chat/core-typings": "workspace:^"
     "@rocket.chat/emitter": "npm:^0.31.25"
     "@rocket.chat/eslint-config": "workspace:^"
-    "@rocket.chat/federation-sdk": "npm:0.1.10"
+    "@rocket.chat/federation-sdk": "npm:0.1.11"
     "@rocket.chat/http-router": "workspace:^"
     "@rocket.chat/license": "workspace:^"
     "@rocket.chat/models": "workspace:^"
@@ -7569,9 +7569,9 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@rocket.chat/federation-sdk@npm:0.1.10":
-  version: 0.1.10
-  resolution: "@rocket.chat/federation-sdk@npm:0.1.10"
+"@rocket.chat/federation-sdk@npm:0.1.11":
+  version: 0.1.11
+  resolution: "@rocket.chat/federation-sdk@npm:0.1.11"
   dependencies:
     "@datastructures-js/priority-queue": "npm:^6.3.3"
     "@noble/ed25519": "npm:^3.0.0"
@@ -7584,7 +7584,7 @@ __metadata:
     zod: "npm:^3.22.4"
   peerDependencies:
     typescript: ~5.9.2
-  checksum: 10/39ec551128f6717b561c122cebab2354635f4d2dd6bb77be7d3581f4cbfe4f6e63953acf4764eba0e9e36239a5019d52d5f0426bc2968bca2674ed4a3ce60284
+  checksum: 10/f45d1d43e28033e3b20022cedbd5825967bbf85346cebc2d6600d490f306fd253713a95bc51ce571e90027087d96497349c694e72a2c2913319d08e1046b0c06
   languageName: node
   linkType: hard
 
@@ -7597,7 +7597,7 @@ __metadata:
     "@rocket.chat/core-typings": "workspace:*"
     "@rocket.chat/emitter": "npm:^0.31.25"
     "@rocket.chat/federation-matrix": "workspace:^"
-    "@rocket.chat/federation-sdk": "npm:0.1.10"
+    "@rocket.chat/federation-sdk": "npm:0.1.11"
     "@rocket.chat/http-router": "workspace:*"
     "@rocket.chat/instance-status": "workspace:^"
     "@rocket.chat/license": "workspace:^"