chore: resource limits service (#10709)

https://linear.app/unleash/issue/2-3927/implement-resource-limits-service

Implements a resource limits service.

The implementation looks trivial (or even redundant) in OSS, but by
implementing a resource limits service we can make this potentially
dynamic and overridable.

src/lib/features/api-tokens/createApiTokenService.ts

@@ -9,6 +9,7 @@ import {
 } from '../events/createEventsService.js';
 import FakeApiTokenStore from '../../../test/fixtures/fake-api-token-store.js';
 import { ApiTokenStore } from '../../db/api-token-store.js';
+import { ResourceLimitsService } from '../resource-limits/resource-limits-service.js';
 
 export const createApiTokenService = (
     db: Db,
@@ -23,11 +24,13 @@ export const createApiTokenService = (
     );
     const environmentStore = new EnvironmentStore(db, eventBus, config);
     const eventService = createEventsService(db, config);
+    const resourceLimitsService = new ResourceLimitsService(config);
 
     return new ApiTokenService(
         { apiTokenStore, environmentStore },
         config,
         eventService,
+        resourceLimitsService,
     );
 };
 
@@ -36,23 +39,27 @@ export const createFakeApiTokenService = (
 ): {
     apiTokenService: ApiTokenService;
     eventService: EventService;
+    resourceLimitsService: ResourceLimitsService;
     apiTokenStore: FakeApiTokenStore;
     environmentStore: IEnvironmentStore;
 } => {
     const apiTokenStore = new FakeApiTokenStore();
     const environmentStore = new FakeEnvironmentStore();
     const eventService = createFakeEventsService(config);
+    const resourceLimitsService = new ResourceLimitsService(config);
 
     const apiTokenService = new ApiTokenService(
         { apiTokenStore, environmentStore },
         config,
         eventService,
+        resourceLimitsService,
     );
 
     return {
         apiTokenService,
         apiTokenStore,
         eventService,
+        resourceLimitsService,
         environmentStore,
     };
 };

src/lib/features/feature-toggle/createFeatureToggleService.ts

@@ -65,12 +65,13 @@ import {
     createFakeFeatureLinkService,
     createFeatureLinkService,
 } from '../feature-links/createFeatureLinkService.js';
+import { ResourceLimitsService } from '../resource-limits/resource-limits-service.js';
 
 export const createFeatureToggleService = (
     db: Db,
     config: IUnleashConfig,
 ): FeatureToggleService => {
-    const { getLogger, eventBus, flagResolver, resourceLimits } = config;
+    const { getLogger, eventBus, flagResolver } = config;
     const featureStrategiesStore = new FeatureStrategiesStore(
         db,
         eventBus,
@@ -138,6 +139,8 @@ export const createFeatureToggleService = (
 
     const featureLinkService = createFeatureLinkService(config)(db);
 
+    const resourceLimitsService = new ResourceLimitsService(config);
+
     const featureToggleService = new FeatureToggleService(
         {
             featureStrategiesStore,
@@ -149,7 +152,7 @@ export const createFeatureToggleService = (
             contextFieldStore,
             strategyStore,
         },
-        { getLogger, flagResolver, eventBus, resourceLimits },
+        { getLogger, flagResolver, eventBus },
         {
             segmentService,
             accessService,
@@ -162,13 +165,14 @@ export const createFeatureToggleService = (
             featureCollaboratorsReadModel,
             featureLinksReadModel,
             featureLinkService,
+            resourceLimitsService,
         },
     );
     return featureToggleService;
 };
 
 export const createFakeFeatureToggleService = (config: IUnleashConfig) => {
-    const { getLogger, flagResolver, resourceLimits } = config;
+    const { getLogger, flagResolver } = config;
     const eventStore = new FakeEventStore();
     const strategyStore = new FakeStrategiesStore();
     const featureStrategiesStore = new FakeFeatureStrategiesStore();
@@ -206,6 +210,8 @@ export const createFakeFeatureToggleService = (config: IUnleashConfig) => {
     const featureLinksReadModel = new FakeFeatureLinksReadModel();
     const { featureLinkService } = createFakeFeatureLinkService(config);
 
+    const resourceLimitsService = new ResourceLimitsService(config);
+
     const featureToggleService = new FeatureToggleService(
         {
             featureStrategiesStore,
@@ -221,7 +227,6 @@ export const createFakeFeatureToggleService = (config: IUnleashConfig) => {
             getLogger,
             flagResolver,
             eventBus: new EventEmitter(),
-            resourceLimits,
         },
         {
             segmentService,
@@ -235,6 +240,7 @@ export const createFakeFeatureToggleService = (config: IUnleashConfig) => {
             featureCollaboratorsReadModel,
             featureLinksReadModel,
             featureLinkService,
+            resourceLimitsService,
         },
     );
     return {

src/lib/features/feature-toggle/feature-toggle-service.ts

@@ -114,9 +114,9 @@ import type { IFeatureLifecycleReadModel } from '../feature-lifecycle/feature-li
 import { throwExceedsLimitError } from '../../error/exceeds-limit-error.js';
 import type { Collaborator } from './types/feature-collaborators-read-model-type.js';
 import { sortStrategies } from '../../util/sortStrategies.js';
-import type { ResourceLimitsSchema } from '../../openapi/index.js';
 import type FeatureLinkService from '../feature-links/feature-link-service.js';
 import type { IFeatureLink } from '../feature-links/feature-links-read-model-type.js';
+import type { ResourceLimitsService } from '../resource-limits/resource-limits-service.js';
 interface IFeatureContext {
     featureName: string;
     projectId: string;
@@ -161,7 +161,7 @@ export type Stores = Pick<
 
 export type Config = Pick<
     IUnleashConfig,
-    'getLogger' | 'flagResolver' | 'eventBus' | 'resourceLimits'
+    'getLogger' | 'flagResolver' | 'eventBus'
 >;
 
 export type ServicesAndReadModels = {
@@ -176,6 +176,7 @@ export type ServicesAndReadModels = {
     featureCollaboratorsReadModel: IFeatureCollaboratorsReadModel;
     featureLinkService: FeatureLinkService;
     featureLinksReadModel: IFeatureLinksReadModel;
+    resourceLimitsService: ResourceLimitsService;
 };
 
 export class FeatureToggleService {
@@ -223,7 +224,7 @@ export class FeatureToggleService {
 
     private eventBus: EventEmitter;
 
-    private resourceLimits: ResourceLimitsSchema;
+    private resourceLimitsService: ResourceLimitsService;
 
     constructor(
         {
@@ -236,7 +237,7 @@ export class FeatureToggleService {
             contextFieldStore,
             strategyStore,
         }: Stores,
-        { getLogger, flagResolver, eventBus, resourceLimits }: Config,
+        { getLogger, flagResolver, eventBus }: Config,
         {
             segmentService,
             accessService,
@@ -249,6 +250,7 @@ export class FeatureToggleService {
             featureCollaboratorsReadModel,
             featureLinksReadModel,
             featureLinkService,
+            resourceLimitsService,
         }: ServicesAndReadModels,
     ) {
         this.logger = getLogger('services/feature-toggle-service.ts');
@@ -273,7 +275,7 @@ export class FeatureToggleService {
         this.featureLinksReadModel = featureLinksReadModel;
         this.featureLinkService = featureLinkService;
         this.eventBus = eventBus;
-        this.resourceLimits = resourceLimits;
+        this.resourceLimitsService = resourceLimitsService;
     }
 
     async validateFeaturesContext(
@@ -396,7 +398,8 @@ export class FeatureToggleService {
         environment: string;
         featureName: string;
     }) {
-        const limit = this.resourceLimits.featureEnvironmentStrategies;
+        const { featureEnvironmentStrategies: limit } =
+            await this.resourceLimitsService.getResourceLimits();
         const existingCount = (
             await this.featureStrategiesStore.getStrategiesForFeatureEnv(
                 featureEnv.projectId,
@@ -412,14 +415,14 @@ export class FeatureToggleService {
         }
     }
 
-    private validateConstraintsLimit(constraints: {
+    private async validateConstraintsLimit(constraints: {
         updated: IConstraint[];
         existing: IConstraint[];
     }) {
         const {
             constraints: constraintsLimit,
             constraintValues: constraintValuesLimit,
-        } = this.resourceLimits;
+        } = await this.resourceLimitsService.getResourceLimits();
 
         if (
             constraints.updated.length > constraintsLimit &&
@@ -711,7 +714,7 @@ export class FeatureToggleService {
         const { name, title, disabled, sortOrder } = strategyConfig;
         let { constraints, parameters, variants } = strategyConfig;
         if (constraints && constraints.length > 0) {
-            this.validateConstraintsLimit({
+            await this.validateConstraintsLimit({
                 updated: constraints,
                 existing: existing?.constraints ?? [],
             });
@@ -1264,7 +1267,8 @@ export class FeatureToggleService {
 
     private async validateFeatureFlagLimit() {
         const currentFlagCount = await this.featureToggleStore.count();
-        const limit = this.resourceLimits.featureFlags;
+        const { featureFlags: limit } =
+            await this.resourceLimitsService.getResourceLimits();
         if (currentFlagCount >= limit) {
             throwExceedsLimitError(this.eventBus, {
                 resource: 'feature flag',

src/lib/features/project/createProjectService.ts

@@ -9,6 +9,7 @@ import {
     FavoritesService,
     GroupService,
     ProjectService,
+    ResourceLimitsService,
 } from '../../services/index.js';
 import FakeGroupStore from '../../../test/fixtures/fake-group-store.js';
 import FakeEventStore from '../../../test/fixtures/fake-event-store.js';
@@ -117,10 +118,13 @@ export const createProjectService = (
 
     const privateProjectChecker = createPrivateProjectChecker(db, config);
 
+    const resourceLimitsService = new ResourceLimitsService(config);
+
     const apiTokenService = new ApiTokenService(
         { apiTokenStore, environmentStore },
         config,
         eventService,
+        resourceLimitsService,
     );
 
     const projectReadModel = createProjectReadModel(
@@ -153,6 +157,7 @@ export const createProjectService = (
         eventService,
         privateProjectChecker,
         apiTokenService,
+        resourceLimitsService,
     );
 };
 
@@ -189,10 +194,13 @@ export const createFakeProjectService = (config: IUnleashConfig) => {
         eventService,
     );
 
+    const resourceLimitsService = new ResourceLimitsService(config);
+
     const apiTokenService = new ApiTokenService(
         { apiTokenStore, environmentStore },
         config,
         eventService,
+        resourceLimitsService,
     );
 
     const projectReadModel = createFakeProjectReadModel();
@@ -221,6 +229,7 @@ export const createFakeProjectService = (config: IUnleashConfig) => {
         eventService,
         privateProjectChecker,
         apiTokenService,
+        resourceLimitsService,
     );
     return {
         projectService,

src/lib/features/project/project-service.ts

@@ -67,10 +67,7 @@ import { calculateAverageTimeToProd } from '../feature-toggle/time-to-production
 import type { IProjectStatsStore } from '../../types/stores/project-stats-store-type.js';
 import { uniqueByKey } from '../../util/unique.js';
 import { BadDataError, PermissionError } from '../../error/index.js';
-import type {
+import type { ProjectDoraMetricsSchema } from '../../openapi/index.js';
-    ProjectDoraMetricsSchema,
-    ResourceLimitsSchema,
-} from '../../openapi/index.js';
 import { checkFeatureNamingData } from '../feature-naming-pattern/feature-naming-validation.js';
 import type { IPrivateProjectChecker } from '../private-project/privateProjectCheckerType.js';
 import type EventService from '../events/event-service.js';
@@ -89,6 +86,7 @@ import { canGrantProjectRole } from './can-grant-project-role.js';
 import { batchExecute } from '../../util/index.js';
 import metricsHelper from '../../util/metrics-helper.js';
 import { FUNCTION_TIME } from '../../metric-events.js';
+import type { ResourceLimitsService } from '../resource-limits/resource-limits-service.js';
 
 type Days = number;
 type Count = number;
@@ -148,7 +146,7 @@ export default class ProjectService {
 
     private isEnterprise: boolean;
 
-    private resourceLimits: ResourceLimitsSchema;
+    private resourceLimitsService: ResourceLimitsService;
 
     private eventBus: EventEmitter;
 
@@ -193,6 +191,7 @@ export default class ProjectService {
         eventService: EventService,
         privateProjectChecker: IPrivateProjectChecker,
         apiTokenService: ApiTokenService,
+        resourceLimitsService: ResourceLimitsService,
     ) {
         this.projectStore = projectStore;
         this.projectOwnersReadModel = projectOwnersReadModel;
@@ -213,7 +212,7 @@ export default class ProjectService {
         this.logger = config.getLogger('services/project-service.js');
         this.flagResolver = config.flagResolver;
         this.isEnterprise = config.isEnterprise;
-        this.resourceLimits = config.resourceLimits;
+        this.resourceLimitsService = resourceLimitsService;
         this.eventBus = config.eventBus;
         this.projectReadModel = projectReadModel;
         this.onboardingReadModel = onboardingReadModel;
@@ -318,7 +317,9 @@ export default class ProjectService {
     }
 
     async validateProjectLimit() {
-        const limit = Math.max(this.resourceLimits.projects, 1);
+        const { projects } =
+            await this.resourceLimitsService.getResourceLimits();
+        const limit = Math.max(projects, 1);
         const projectCount = await this.projectStore.count();
 
         if (projectCount >= limit) {

src/lib/features/resource-limits/resource-limits-service.ts

@@ -0,0 +1,14 @@
+import type { IUnleashConfig } from '../../types/option.js';
+import type { ResourceLimitsSchema } from '../../openapi/index.js';
+
+export class ResourceLimitsService {
+    private config: IUnleashConfig;
+
+    constructor(config: IUnleashConfig) {
+        this.config = config;
+    }
+
+    async getResourceLimits(): Promise<ResourceLimitsSchema> {
+        return this.config.resourceLimits;
+    }
+}

src/lib/features/segment/createSegmentService.ts

@@ -1,5 +1,5 @@
 import type { Db, IUnleashConfig } from '../../types/index.js';
-import { SegmentService } from '../../services/index.js';
+import { ResourceLimitsService, SegmentService } from '../../services/index.js';
 import type { ISegmentService } from './segment-service-interface.js';
 import FeatureStrategiesStore from '../feature-toggle/feature-toggle-strategies-store.js';
 import SegmentStore from './segment-store.js';
@@ -51,6 +51,8 @@ export const createSegmentService = (
 
     const eventService = createEventsService(db, config);
 
+    const resourceLimitsService = new ResourceLimitsService(config);
+
     return new SegmentService(
         { segmentStore, featureStrategiesStore },
         changeRequestAccessReadModel,
@@ -58,6 +60,7 @@ export const createSegmentService = (
         config,
         eventService,
         privateProjectChecker,
+        resourceLimitsService,
     );
 };
 
@@ -74,6 +77,8 @@ export const createFakeSegmentService = (
 
     const eventService = createFakeEventsService(config);
 
+    const resourceLimitsService = new ResourceLimitsService(config);
+
     return new SegmentService(
         { segmentStore, featureStrategiesStore },
         changeRequestAccessReadModel,
@@ -81,5 +86,6 @@ export const createFakeSegmentService = (
         config,
         eventService,
         privateProjectChecker,
+        resourceLimitsService,
     );
 };

src/lib/features/segment/segment-service.ts

@@ -25,11 +25,9 @@ import type { IChangeRequestAccessReadModel } from '../change-request-access-ser
 import type { IPrivateProjectChecker } from '../private-project/privateProjectCheckerType.js';
 import type EventService from '../events/event-service.js';
 import type { IChangeRequestSegmentUsageReadModel } from '../change-request-segment-usage-service/change-request-segment-usage-read-model.js';
-import type {
+import type { UpsertSegmentSchema } from '../../openapi/index.js';
-    ResourceLimitsSchema,
-    UpsertSegmentSchema,
-} from '../../openapi/index.js';
 import { throwExceedsLimitError } from '../../error/exceeds-limit-error.js';
+import type { ResourceLimitsService } from '../resource-limits/resource-limits-service.js';
 
 export class SegmentService implements ISegmentService {
     private logger: Logger;
@@ -50,7 +48,7 @@ export class SegmentService implements ISegmentService {
 
     private privateProjectChecker: IPrivateProjectChecker;
 
-    private resourceLimits: ResourceLimitsSchema;
+    private resourceLimitsService: ResourceLimitsService;
 
     constructor(
         {
@@ -62,6 +60,7 @@ export class SegmentService implements ISegmentService {
         config: IUnleashConfig,
         eventService: EventService,
         privateProjectChecker: IPrivateProjectChecker,
+        resourceLimitsService: ResourceLimitsService,
     ) {
         this.segmentStore = segmentStore;
         this.featureStrategiesStore = featureStrategiesStore;
@@ -72,7 +71,7 @@ export class SegmentService implements ISegmentService {
         this.privateProjectChecker = privateProjectChecker;
         this.logger = config.getLogger('services/segment-service.ts');
         this.flagResolver = config.flagResolver;
-        this.resourceLimits = config.resourceLimits;
+        this.resourceLimitsService = resourceLimitsService;
         this.config = config;
     }
 
@@ -136,7 +135,8 @@ export class SegmentService implements ISegmentService {
     }
 
     async validateSegmentLimit() {
-        const limit = this.resourceLimits.segments;
+        const { segments: limit } =
+            await this.resourceLimitsService.getResourceLimits();
 
         const segmentCount = await this.segmentStore.count();
 

src/lib/services/api-token-service.ts

@@ -31,9 +31,9 @@ import type EventService from '../features/events/event-service.js';
 import { addMinutes, isPast } from 'date-fns';
 import metricsHelper from '../util/metrics-helper.js';
 import { FUNCTION_TIME } from '../metric-events.js';
-import type { ResourceLimitsSchema } from '../openapi/index.js';
 import { throwExceedsLimitError } from '../error/exceeds-limit-error.js';
 import type EventEmitter from 'events';
+import type { ResourceLimitsService } from '../features/resource-limits/resource-limits-service.js';
 
 const resolveTokenPermissions = (tokenType: string) => {
     if (tokenType === ApiTokenType.ADMIN) {
@@ -73,7 +73,7 @@ export class ApiTokenService {
 
     private timer: Function;
 
-    private resourceLimits: ResourceLimitsSchema;
+    private resourceLimitsService: ResourceLimitsService;
 
     private eventBus: EventEmitter;
 
@@ -84,20 +84,17 @@ export class ApiTokenService {
         }: Pick<IUnleashStores, 'apiTokenStore' | 'environmentStore'>,
         config: Pick<
             IUnleashConfig,
-            | 'getLogger'
+            'getLogger' | 'authentication' | 'flagResolver' | 'eventBus'
-            | 'authentication'
-            | 'flagResolver'
-            | 'eventBus'
-            | 'resourceLimits'
         >,
         eventService: EventService,
+        resourceLimitsService: ResourceLimitsService,
     ) {
         this.store = apiTokenStore;
         this.eventService = eventService;
+        this.resourceLimitsService = resourceLimitsService;
         this.environmentStore = environmentStore;
         this.flagResolver = config.flagResolver;
         this.logger = config.getLogger('/services/api-token-service.ts');
-        this.resourceLimits = config.resourceLimits;
         if (!this.flagResolver.isEnabled('useMemoizedActiveTokens')) {
             // This is probably not needed because the scheduler will run it
             this.fetchActiveTokens();
@@ -321,7 +318,8 @@ export class ApiTokenService {
 
     private async validateApiTokenLimit() {
         const currentTokenCount = await this.store.count();
-        const limit = this.resourceLimits.apiTokens;
+        const { apiTokens: limit } =
+            await this.resourceLimitsService.getResourceLimits();
         if (currentTokenCount >= limit) {
             throwExceedsLimitError(this.eventBus, {
                 resource: 'api token',

src/lib/services/index.ts

@@ -171,6 +171,7 @@ import { UnknownFlagsService } from '../features/metrics/unknown-flags/unknown-f
 import type FeatureLinkService from '../features/feature-links/feature-link-service.js';
 import { createUserService } from '../features/users/createUserService.js';
 import { UiConfigService } from '../ui-config/ui-config-service.js';
+import { ResourceLimitsService } from '../features/resource-limits/resource-limits-service.js';
 
 export const createServices = (
     stores: IUnleashStores,
@@ -205,6 +206,8 @@ export const createServices = (
 
     const unknownFlagsService = new UnknownFlagsService(stores, config);
 
+    const resourceLimitsService = new ResourceLimitsService(config);
+
     // Initialize custom metrics service
     const customMetricsService = new CustomMetricsService(config);
 
@@ -283,6 +286,7 @@ export const createServices = (
         config,
         eventService,
         privateProjectChecker,
+        resourceLimitsService,
     );
 
     const clientInstanceService = new ClientInstanceService(
@@ -449,6 +453,7 @@ export const createServices = (
         frontendApiService,
         maintenanceService,
         sessionService,
+        resourceLimitsService,
     });
 
     return {
@@ -525,6 +530,7 @@ export const createServices = (
         featureLinkService,
         unknownFlagsService,
         uiConfigService,
+        resourceLimitsService,
     };
 };
 
@@ -581,6 +587,8 @@ export {
     UniqueConnectionService,
     FeatureLifecycleReadModel,
     UnknownFlagsService,
+    UiConfigService,
+    ResourceLimitsService,
 };
 
 export interface IUnleashServices {
@@ -657,4 +665,5 @@ export interface IUnleashServices {
     featureLinkService: FeatureLinkService;
     unknownFlagsService: UnknownFlagsService;
     uiConfigService: UiConfigService;
+    resourceLimitsService: ResourceLimitsService;
 }

src/lib/ui-config/ui-config-service.ts

@@ -17,6 +17,7 @@ import {
     simpleAuthSettingsKey,
 } from '../types/settings/simple-auth-settings.js';
 import version from '../util/version.js';
+import type { ResourceLimitsService } from '../features/resource-limits/resource-limits-service.js';
 
 export class UiConfigService {
     private config: IUnleashConfig;
@@ -33,6 +34,8 @@ export class UiConfigService {
 
     private maintenanceService: MaintenanceService;
 
+    private resourceLimitsService: ResourceLimitsService;
+
     private flagResolver: IFlagResolver;
 
     constructor(
@@ -44,6 +47,7 @@ export class UiConfigService {
             frontendApiService,
             maintenanceService,
             sessionService,
+            resourceLimitsService,
         }: Pick<
             IUnleashServices,
             | 'versionService'
@@ -52,6 +56,7 @@ export class UiConfigService {
             | 'frontendApiService'
             | 'maintenanceService'
             | 'sessionService'
+            | 'resourceLimitsService'
         >,
     ) {
         this.config = config;
@@ -62,6 +67,7 @@ export class UiConfigService {
         this.frontendApiService = frontendApiService;
         this.maintenanceService = maintenanceService;
         this.sessionService = sessionService;
+        this.resourceLimitsService = resourceLimitsService;
     }
 
     async getMaxSessionsCount(): Promise<number> {
@@ -114,7 +120,8 @@ export class UiConfigService {
             frontendApiOrigins: frontendSettings.frontendApiOrigins,
             versionInfo: await this.versionService.getVersionInfo(),
             prometheusAPIAvailable: this.config.prometheusApi !== undefined,
-            resourceLimits: this.config.resourceLimits,
+            resourceLimits:
+                await this.resourceLimitsService.getResourceLimits(),
             disablePasswordAuth,
             maintenanceMode,
             feedbackUriPath: this.config.feedbackUriPath,