fix(admin): allow single community mode to be turned back on (#1684)

fluxer_admin/openapi-admin.json

@@ -12543,7 +12543,6 @@
 						"type": "object",
 						"properties": {
 							"single_community_enabled": {"type": "boolean"},
-							"single_community_locked": {"type": "boolean"},
 							"single_community_guild_id": {"nullable": true, "type": "string"},
 							"direct_messages_disabled": {"type": "boolean"},
 							"direct_messages_locked": {"type": "boolean"},
@@ -12578,7 +12577,6 @@
 						},
 						"required": [
 							"single_community_enabled",
-							"single_community_locked",
 							"single_community_guild_id",
 							"direct_messages_disabled",
 							"direct_messages_locked",

fluxer_admin/src/api/types/instance_config.rs

@@ -24,8 +24,6 @@ pub struct InstanceConfigResponse {
 pub struct InstancePolicyResponse {
     #[serde(default)]
     pub single_community_enabled: bool,
-    #[serde(default)]
-    pub single_community_locked: bool,
     pub single_community_guild_id: Option<String>,
     #[serde(default)]
     pub direct_messages_disabled: bool,
@@ -45,7 +43,6 @@ impl Default for InstancePolicyResponse {
     fn default() -> Self {
         Self {
             single_community_enabled: false,
-            single_community_locked: false,
             single_community_guild_id: None,
             direct_messages_disabled: false,
             direct_messages_locked: false,

fluxer_admin/src/routes/system_actions.rs

@@ -216,7 +216,11 @@ pub async fn instance_config_post(
             Err(message) => FlashData::error(message),
         },
         "disable_single_community" => {
-            let update = build_disable_single_community_update();
+            let update = build_single_community_update(false);
+            instance_config_result(client.update_instance_config(&update).await)
+        }
+        "enable_single_community" => {
+            let update = build_single_community_update(true);
             instance_config_result(client.update_instance_config(&update).await)
         }
         "create_registration_url" => match build_create_registration_url_request(&form) {
@@ -696,14 +700,14 @@ fn build_smtp_test_request(form: &MultiValueForm) -> Result<InstanceEmailSmtpTes
     })
 }
 
-fn build_disable_single_community_update() -> InstanceConfigUpdateRequest {
+fn build_single_community_update(enabled: bool) -> InstanceConfigUpdateRequest {
     InstanceConfigUpdateRequest {
         gateway_rollout: None,
         registration: None,
         sso: None,
         app_public: None,
         policy: Some(InstancePolicyUpdateRequest {
-            single_community_enabled: Some(false),
+            single_community_enabled: Some(enabled),
             single_community_name: None,
             direct_messages_disabled: None,
             premium_mode: None,

fluxer_admin/src/templates/pages/instance_config.rs

@@ -208,18 +208,14 @@ fn single_community_form(base: &str, csrf_token: &str, policy: &InstancePolicyRe
             div class="flex flex-wrap items-center gap-2" {
                 h3 class="text-sm font-semibold text-neutral-900" { "Single community" }
                 (badge(status.0, status.1))
-                @if policy.single_community_locked {
-                    (badge("Locked", BadgeVariant::Warning))
-                }
             }
             @if let Some(guild_id) = policy.single_community_guild_id.as_deref() {
                 p class="break-all text-xs text-neutral-500" { "Community guild ID: " (guild_id) }
             }
-            @if policy.single_community_enabled && !policy.single_community_locked {
+            @if policy.single_community_enabled {
                 p class="text-sm text-neutral-500" {
-                    "This instance funnels every member into a single community. Disabling it is \
-                     permanent: single-community mode can only be enabled again from the \
-                     self-host setup wizard, never from this panel."
+                    "This instance funnels every member into a single community. You can turn this \
+                     off and on again from here. The community itself is kept either way."
                 }
                 form method="post" action={(base) "/instance-config?action=disable_single_community"} {
                     (csrf_input(csrf_token))
@@ -227,15 +223,21 @@ fn single_community_form(base: &str, csrf_token: &str, policy: &InstancePolicyRe
                         (danger_button("Disable single-community mode"))
                     }))
                 }
-            } @else if policy.single_community_enabled {
+            } @else if policy.single_community_guild_id.is_some() {
                 p class="text-sm text-neutral-500" {
-                    "Single-community mode is enabled and locked for this instance. It cannot be \
-                     changed from the admin panel."
+                    "Single-community mode is off. Turning it on again reuses the community above \
+                     if it still exists, otherwise a new one is created."
+                }
+                form method="post" action={(base) "/instance-config?action=enable_single_community"} {
+                    (csrf_input(csrf_token))
+                    (form_actions(html! {
+                        (submit_button("Enable single-community mode"))
+                    }))
                 }
             } @else {
                 p class="text-sm text-neutral-500" {
-                    "Single-community mode is off. It can only be turned on from the self-host \
-                     setup wizard, not from this panel."
+                    "Single-community mode is off. It can only be turned on for the first time \
+                     from the self-host setup wizard."
                 }
             }
         }

fluxer_api/src/api/admin/controllers/InstanceConfigAdminController.ts

@@ -91,7 +91,6 @@ async function buildInstanceConfigResponse(): Promise<InstanceConfigResponse> {
 		app_public: appPublic,
 		policy: {
 			single_community_enabled: policy.single_community_enabled,
-			single_community_locked: policy.single_community_locked,
 			single_community_guild_id: policy.single_community_guild_id,
 			direct_messages_disabled: policy.direct_messages_disabled,
 			direct_messages_locked: policy.direct_messages_locked,
@@ -551,20 +550,19 @@ async function applyInstancePolicyUpdate(
 		policy.single_community_enabled !== current.single_community_enabled
 	) {
 		if (policy.single_community_enabled) {
-			if (appPublic.setup.configured || current.single_community_locked) {
+			if (appPublic.setup.configured && current.single_community_guild_id == null) {
 				throw new InstancePolicyTransitionNotAllowedError();
 			}
 			const adminUser = await ctx.get('userRepository').findUnique(ctx.get('adminUserId'));
 			if (!adminUser) {
 				throw new InstancePolicyTransitionNotAllowedError();
 			}
-			await ctx.get('singleCommunityService').createStockCommunity({
+			await ctx.get('singleCommunityService').ensureStockCommunity({
 				owner: adminUser,
 				name: policy.single_community_name?.trim() || appPublic.branding.product_name,
 			});
 		} else {
 			patch.single_community_enabled = false;
-			patch.single_community_locked = true;
 		}
 	}
 	if (

fluxer_api/src/api/instance/InstanceConfigRepository.ts

@@ -77,7 +77,6 @@ export type InstancePremiumMode = 'mirror' | 'everyone';
 
 export interface InstancePolicyConfig {
 	single_community_enabled: boolean;
-	single_community_locked: boolean;
 	single_community_guild_id: string | null;
 	direct_messages_disabled: boolean;
 	direct_messages_locked: boolean;
@@ -396,7 +395,6 @@ function normalizeAppPublicConfig(value: unknown): InstanceAppPublicConfig {
 
 const DEFAULT_INSTANCE_POLICY_CONFIG: InstancePolicyConfig = {
 	single_community_enabled: false,
-	single_community_locked: false,
 	single_community_guild_id: null,
 	direct_messages_disabled: false,
 	direct_messages_locked: false,
@@ -420,7 +418,6 @@ function normalizeInstancePolicyConfig(value: unknown): InstancePolicyConfig {
 	}
 	return {
 		single_community_enabled: value.single_community_enabled === true,
-		single_community_locked: value.single_community_locked === true,
 		single_community_guild_id: normalizeNullableString(value.single_community_guild_id),
 		direct_messages_disabled: value.direct_messages_disabled === true,
 		direct_messages_locked: value.direct_messages_locked === true,

fluxer_api/src/api/instance/SingleCommunityService.ts

@@ -50,6 +50,37 @@ export class SingleCommunityService {
 		}
 	}
 
+	async ensureStockCommunity(params: {owner: User; name: string}): Promise<GuildID> {
+		const policy = await this.instanceConfigRepository.getInstancePolicyConfig();
+		const designatedGuildId = await this.findDesignatedGuild(policy.single_community_guild_id);
+		if (designatedGuildId != null) {
+			await this.instanceConfigRepository.setInstancePolicyConfig({
+				single_community_enabled: true,
+				single_community_guild_id: designatedGuildId.toString(),
+			});
+			return designatedGuildId;
+		}
+		return this.createStockCommunity(params);
+	}
+
+	private async findDesignatedGuild(rawGuildId: string | null): Promise<GuildID | null> {
+		if (!rawGuildId) {
+			return null;
+		}
+		let guildId: GuildID;
+		try {
+			guildId = createGuildID(BigInt(rawGuildId));
+		} catch {
+			return null;
+		}
+		try {
+			await this.guildDataService.getGuildSystem(guildId);
+			return guildId;
+		} catch {
+			return null;
+		}
+	}
+
 	async createStockCommunity(params: {owner: User; name: string}): Promise<GuildID> {
 		const guild = await this.guildDataService.createGuild({user: params.owner, data: {name: params.name}});
 		const guildId = createGuildID(BigInt(guild.id));

fluxer_api/src/api/instance/tests/SingleCommunityService.test.ts

@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+import {describe, expect, it} from 'vitest';
+import type {User} from '../../models/User';
+import type {InstancePolicyConfig} from '../InstanceConfigRepository';
+import {SingleCommunityService} from '../SingleCommunityService';
+
+const EXISTING_GUILD_ID = '1234567890123456789';
+const OWNER = {id: 42n} as unknown as User;
+
+interface Harness {
+	service: SingleCommunityService;
+	written: Array<Partial<InstancePolicyConfig>>;
+	createdNames: Array<string>;
+}
+
+function createHarness(params: {designatedGuildId: string | null; designatedGuildExists: boolean}): Harness {
+	const written: Array<Partial<InstancePolicyConfig>> = [];
+	const createdNames: Array<string> = [];
+	let nextCreatedGuildId = 999n;
+	const instanceConfigRepository = {
+		getInstancePolicyConfig: async () => ({
+			single_community_enabled: false,
+			single_community_guild_id: params.designatedGuildId,
+		}),
+		setInstancePolicyConfig: async (patch: Partial<InstancePolicyConfig>) => {
+			written.push(patch);
+		},
+	};
+	const guildDataService = {
+		getGuildSystem: async () => {
+			if (!params.designatedGuildExists) {
+				throw new Error('unknown guild');
+			}
+			return {} as never;
+		},
+		createGuild: async ({data}: {data: {name: string}}) => {
+			createdNames.push(data.name);
+			nextCreatedGuildId += 1n;
+			return {id: nextCreatedGuildId.toString()} as never;
+		},
+	};
+	const service = new SingleCommunityService(
+		instanceConfigRepository as never,
+		guildDataService as never,
+		null as never,
+	);
+	return {service, written, createdNames};
+}
+
+describe('SingleCommunityService.ensureStockCommunity', () => {
+	it('reuses the designated community when it still exists', async () => {
+		const harness = createHarness({designatedGuildId: EXISTING_GUILD_ID, designatedGuildExists: true});
+		const guildId = await harness.service.ensureStockCommunity({owner: OWNER, name: 'Fluxer'});
+		expect(guildId.toString()).toBe(EXISTING_GUILD_ID);
+		expect(harness.createdNames).toEqual([]);
+		expect(harness.written).toEqual([{single_community_enabled: true, single_community_guild_id: EXISTING_GUILD_ID}]);
+	});
+
+	it('creates a fresh community when the designated one was deleted', async () => {
+		const harness = createHarness({designatedGuildId: EXISTING_GUILD_ID, designatedGuildExists: false});
+		const guildId = await harness.service.ensureStockCommunity({owner: OWNER, name: 'Fluxer'});
+		expect(guildId.toString()).not.toBe(EXISTING_GUILD_ID);
+		expect(harness.createdNames).toEqual(['Fluxer']);
+	});
+
+	it('creates a fresh community when the instance never designated one', async () => {
+		const harness = createHarness({designatedGuildId: null, designatedGuildExists: false});
+		await harness.service.ensureStockCommunity({owner: OWNER, name: 'Fluxer'});
+		expect(harness.createdNames).toEqual(['Fluxer']);
+	});
+
+	it('creates a fresh community when the stored guild id is not a snowflake', async () => {
+		const harness = createHarness({designatedGuildId: 'not-a-snowflake', designatedGuildExists: true});
+		await harness.service.ensureStockCommunity({owner: OWNER, name: 'Fluxer'});
+		expect(harness.createdNames).toEqual(['Fluxer']);
+	});
+});

packages/schema/src/domains/admin/AdminSchemas.ts

@@ -508,7 +508,6 @@ const AppPublicConfigUpdateRequest = z.object({
 
 const InstancePolicyResponse = z.object({
 	single_community_enabled: z.boolean(),
-	single_community_locked: z.boolean(),
 	single_community_guild_id: z.string().nullable(),
 	direct_messages_disabled: z.boolean(),
 	direct_messages_locked: z.boolean(),