feat(server): runtime setting support (#5602)

---

<details open="true"><summary>Generated summary (powered by <a href="https://app.graphite.dev">Graphite</a>)</summary>

> ## TL;DR
> This pull request adds a new migration file, a new model, and new modules related to runtime settings. It also introduces a new `Runtime` service that allows getting, setting, and updating runtime configurations.
>
> ## What changed
> - Added a new migration file `migration.sql` that creates a table called `application_settings` with columns `key` and `value`.
> - Added a new model `ApplicationSetting` with properties `key` and `value`.
> - Added a new module `RuntimeSettingModule` that exports the `Runtime` service.
> - Added a new service `Runtime` that provides methods for getting, setting, and updating runtime configurations.
> - Modified the `app.module.ts` file to import the `RuntimeSettingModule`.
> - Modified the `index.ts` file in the `fundamentals` directory to export the `Runtime` service.
> - Added a new file `def.ts` in the `runtime` directory that defines the runtime configurations and provides a default implementation.
> - Added a new file `service.ts` in the `runtime` directory that implements the `Runtime` service.
>
> ## How to test
> 1. Run the migration script to create the `application_settings` table.
> 2. Use the `Runtime` service to get, set, and update runtime configurations.
> 3. Verify that the runtime configurations are stored correctly in the database and can be retrieved and modified using the `Runtime` service.
>
> ## Why make this change
> This change introduces a new feature related to runtime settings. The `Runtime` service allows the application to dynamically manage and modify runtime configurations without requiring a restart. This provides flexibility and allows for easier customization and configuration of the application.
</details>

packages/backend/server/src/core/config/config.ts

@@ -0,0 +1,23 @@
+import { defineRuntimeConfig, ModuleConfig } from '../../fundamentals/config';
+
+export interface ServerFlags {
+  earlyAccessControl: boolean;
+  syncClientVersionCheck: boolean;
+}
+
+declare module '../../fundamentals/config' {
+  interface AppConfig {
+    flags: ModuleConfig<never, ServerFlags>;
+  }
+}
+
+defineRuntimeConfig('flags', {
+  earlyAccessControl: {
+    desc: 'Only allow users with early access features to access the app',
+    default: false,
+  },
+  syncClientVersionCheck: {
+    desc: 'Only allow client with exact the same version with server to establish sync connections',
+    default: false,
+  },
+});

packages/backend/server/src/core/config/index.ts

@@ -0,0 +1,12 @@
+import './config';
+
+import { Module } from '@nestjs/common';
+
+import { ServerConfigResolver, ServerRuntimeConfigResolver } from './resolver';
+
+@Module({
+  providers: [ServerConfigResolver, ServerRuntimeConfigResolver],
+})
+export class ServerConfigModule {}
+export { ADD_ENABLED_FEATURES, ServerConfigType } from './resolver';
+export { ServerFeature } from './types';

packages/backend/server/src/core/config/resolver.ts

@@ -0,0 +1,207 @@
+import {
+  Args,
+  Field,
+  GraphQLISODateTime,
+  Mutation,
+  ObjectType,
+  Query,
+  registerEnumType,
+  ResolveField,
+  Resolver,
+} from '@nestjs/graphql';
+import { RuntimeConfig, RuntimeConfigType } from '@prisma/client';
+import { GraphQLJSON, GraphQLJSONObject } from 'graphql-scalars';
+
+import { Config, DeploymentType, URLHelper } from '../../fundamentals';
+import { Public } from '../auth';
+import { Admin } from '../common';
+import { ServerFlags } from './config';
+import { ServerFeature } from './types';
+
+const ENABLED_FEATURES: Set<ServerFeature> = new Set();
+export function ADD_ENABLED_FEATURES(feature: ServerFeature) {
+  ENABLED_FEATURES.add(feature);
+}
+
+registerEnumType(ServerFeature, {
+  name: 'ServerFeature',
+});
+
+registerEnumType(DeploymentType, {
+  name: 'ServerDeploymentType',
+});
+
+@ObjectType()
+export class PasswordLimitsType {
+  @Field()
+  minLength!: number;
+  @Field()
+  maxLength!: number;
+}
+
+@ObjectType()
+export class CredentialsRequirementType {
+  @Field()
+  password!: PasswordLimitsType;
+}
+
+@ObjectType()
+export class ServerConfigType {
+  @Field({
+    description:
+      'server identical name could be shown as badge on user interface',
+  })
+  name!: string;
+
+  @Field({ description: 'server version' })
+  version!: string;
+
+  @Field({ description: 'server base url' })
+  baseUrl!: string;
+
+  @Field(() => DeploymentType, { description: 'server type' })
+  type!: DeploymentType;
+
+  /**
+   * @deprecated
+   */
+  @Field({ description: 'server flavor', deprecationReason: 'use `features`' })
+  flavor!: string;
+
+  @Field(() => [ServerFeature], { description: 'enabled server features' })
+  features!: ServerFeature[];
+
+  @Field({ description: 'enable telemetry' })
+  enableTelemetry!: boolean;
+}
+
+registerEnumType(RuntimeConfigType, {
+  name: 'RuntimeConfigType',
+});
+@ObjectType()
+export class ServerRuntimeConfigType implements Partial<RuntimeConfig> {
+  @Field()
+  id!: string;
+
+  @Field()
+  module!: string;
+
+  @Field()
+  key!: string;
+
+  @Field()
+  description!: string;
+
+  @Field(() => GraphQLJSON)
+  value!: any;
+
+  @Field(() => RuntimeConfigType)
+  type!: RuntimeConfigType;
+
+  @Field(() => GraphQLISODateTime)
+  updatedAt!: Date;
+}
+
+@ObjectType()
+export class ServerFlagsType implements ServerFlags {
+  @Field()
+  earlyAccessControl!: boolean;
+
+  @Field()
+  syncClientVersionCheck!: boolean;
+}
+
+@Resolver(() => ServerConfigType)
+export class ServerConfigResolver {
+  constructor(
+    private readonly config: Config,
+    private readonly url: URLHelper
+  ) {}
+
+  @Public()
+  @Query(() => ServerConfigType, {
+    description: 'server config',
+  })
+  serverConfig(): ServerConfigType {
+    return {
+      name: this.config.serverName,
+      version: this.config.version,
+      baseUrl: this.url.home,
+      type: this.config.type,
+      // BACKWARD COMPATIBILITY
+      // the old flavors contains `selfhosted` but it actually not flavor but deployment type
+      // this field should be removed after frontend feature flags implemented
+      flavor: this.config.type,
+      features: Array.from(ENABLED_FEATURES),
+      enableTelemetry: this.config.metrics.telemetry.enabled,
+    };
+  }
+
+  @ResolveField(() => CredentialsRequirementType, {
+    description: 'credentials requirement',
+  })
+  async credentialsRequirement() {
+    const config = await this.config.runtime.fetchAll({
+      'auth/password.max': true,
+      'auth/password.min': true,
+    });
+
+    return {
+      password: {
+        minLength: config['auth/password.min'],
+        maxLength: config['auth/password.max'],
+      },
+    };
+  }
+
+  @ResolveField(() => ServerFlagsType, {
+    description: 'server flags',
+  })
+  async flags(): Promise<ServerFlagsType> {
+    const records = await this.config.runtime.list('flags');
+
+    return records.reduce((flags, record) => {
+      flags[record.key as keyof ServerFlagsType] = record.value as any;
+      return flags;
+    }, {} as ServerFlagsType);
+  }
+}
+
+@Resolver(() => ServerRuntimeConfigType)
+export class ServerRuntimeConfigResolver {
+  constructor(private readonly config: Config) {}
+
+  @Admin()
+  @Query(() => [ServerRuntimeConfigType], {
+    description: 'get all server runtime configurable settings',
+  })
+  serverRuntimeConfig(): Promise<ServerRuntimeConfigType[]> {
+    return this.config.runtime.list();
+  }
+
+  @Admin()
+  @Mutation(() => ServerRuntimeConfigType, {
+    description: 'update server runtime configurable setting',
+  })
+  async updateRuntimeConfig(
+    @Args('id') id: string,
+    @Args({ type: () => GraphQLJSON, name: 'value' }) value: any
+  ): Promise<ServerRuntimeConfigType> {
+    return await this.config.runtime.set(id as any, value);
+  }
+
+  @Admin()
+  @Mutation(() => [ServerRuntimeConfigType], {
+    description: 'update multiple server runtime configurable settings',
+  })
+  async updateRuntimeConfigs(
+    @Args({ type: () => GraphQLJSONObject, name: 'updates' }) updates: any
+  ): Promise<ServerRuntimeConfigType[]> {
+    const keys = Object.keys(updates);
+    const results = await Promise.all(
+      keys.map(key => this.config.runtime.set(key as any, updates[key]))
+    );
+
+    return results;
+  }
+}

packages/backend/server/src/core/config/types.ts

@@ -0,0 +1,5 @@
+export enum ServerFeature {
+  Copilot = 'copilot',
+  Payment = 'payment',
+  OAuth = 'oauth',
+}