feat(web, server): Ability to use config file instead of admin UI (#3836)

* implement method to read config file

* getConfig returns config file if present

* return isConfigFile for http requests

* disable elements if config file is used, show message if config file is set, copy existing config to clipboard

* fix allowing partial configuration files

* add new env variable to docs

* fix tests

* minor refactoring, address review

* adapt config type in frontend

* remove unnecessary imports

* move config file reading to system-config repo

* add documentation

* fix code formatting in system settings page

* add validator for config file

* fix formatting in docs

* update generated files

* throw error when trying to update config. e.g. via cli or api

* switch to feature flags for isConfigFile

* refactoring

* refactor: config file

* chore: open api

* feat: always show copy/export buttons

* fix: default flags

* refactor: copy to clipboard

---------

Co-authored-by: Jason Rasmussen <jrasm91@gmail.com>

server/src/domain/system-config/system-config.core.ts

@@ -10,10 +10,13 @@ import {
   VideoCodec,
 } from '@app/infra/entities';
 import { BadRequestException, ForbiddenException, Injectable, Logger } from '@nestjs/common';
+import { plainToClass } from 'class-transformer';
+import { validate } from 'class-validator';
 import * as _ from 'lodash';
 import { Subject } from 'rxjs';
 import { DeepPartial } from 'typeorm';
 import { QueueName } from '../job/job.constants';
+import { SystemConfigDto } from './dto';
 import { ISystemConfigRepository } from './system-config.repository';
 
 export type SystemConfigValidator = (config: SystemConfig) => void | Promise<void>;
@@ -87,6 +90,7 @@ export enum FeatureFlag {
   OAUTH = 'oauth',
   OAUTH_AUTO_LAUNCH = 'oauthAutoLaunch',
   PASSWORD_LOGIN = 'passwordLogin',
+  CONFIG_FILE = 'configFile',
 }
 
 export type FeatureFlags = Record<FeatureFlag, boolean>;
@@ -97,6 +101,7 @@ const singleton = new Subject<SystemConfig>();
 export class SystemConfigCore {
   private logger = new Logger(SystemConfigCore.name);
   private validators: SystemConfigValidator[] = [];
+  private configCache: SystemConfig | null = null;
 
   public config$ = singleton;
 
@@ -120,6 +125,8 @@ export class SystemConfigCore {
           throw new BadRequestException('OAuth is not enabled');
         case FeatureFlag.PASSWORD_LOGIN:
           throw new BadRequestException('Password login is not enabled');
+        case FeatureFlag.CONFIG_FILE:
+          throw new BadRequestException('Config file is not set');
         default:
           throw new ForbiddenException(`Missing required feature: ${feature}`);
       }
@@ -146,6 +153,7 @@ export class SystemConfigCore {
       [FeatureFlag.OAUTH]: config.oauth.enabled,
       [FeatureFlag.OAUTH_AUTO_LAUNCH]: config.oauth.autoLaunch,
       [FeatureFlag.PASSWORD_LOGIN]: config.passwordLogin.enabled,
+      [FeatureFlag.CONFIG_FILE]: !!process.env.IMMICH_CONFIG_FILE,
     };
   }
 
@@ -157,18 +165,16 @@ export class SystemConfigCore {
     this.validators.push(validator);
   }
 
-  public async getConfig() {
-    const overrides = await this.repository.load();
-    const config: DeepPartial<SystemConfig> = {};
-    for (const { key, value } of overrides) {
-      // set via dot notation
-      _.set(config, key, value);
-    }
-
-    return _.defaultsDeep(config, defaults) as SystemConfig;
+  public getConfig(force = false): Promise<SystemConfig> {
+    const configFilePath = process.env.IMMICH_CONFIG_FILE;
+    return configFilePath ? this.loadFromFile(configFilePath, force) : this.loadFromDatabase();
   }
 
   public async updateConfig(config: SystemConfig): Promise<SystemConfig> {
+    if (await this.hasFeature(FeatureFlag.CONFIG_FILE)) {
+      throw new BadRequestException('Cannot update configuration while IMMICH_CONFIG_FILE is in use');
+    }
+
     try {
       for (const validator of this.validators) {
         await validator(config);
@@ -211,8 +217,45 @@ export class SystemConfigCore {
   }
 
   public async refreshConfig() {
-    const newConfig = await this.getConfig();
+    const newConfig = await this.getConfig(true);
 
     this.config$.next(newConfig);
   }
+
+  private async loadFromDatabase() {
+    const config: DeepPartial<SystemConfig> = {};
+    const overrides = await this.repository.load();
+    for (const { key, value } of overrides) {
+      // set via dot notation
+      _.set(config, key, value);
+    }
+
+    return _.defaultsDeep(config, defaults) as SystemConfig;
+  }
+
+  private async loadFromFile(filepath: string, force = false) {
+    if (force || !this.configCache) {
+      try {
+        const overrides = JSON.parse((await this.repository.readFile(filepath)).toString());
+        const config = plainToClass(SystemConfigDto, _.defaultsDeep(overrides, defaults));
+
+        const errors = await validate(config, {
+          whitelist: true,
+          forbidNonWhitelisted: true,
+          forbidUnknownValues: true,
+        });
+        if (errors.length > 0) {
+          this.logger.error('Validation error', errors);
+          throw new Error(`Invalid value(s) in file: ${errors}`);
+        }
+
+        this.configCache = config;
+      } catch (error: Error | any) {
+        this.logger.error(`Unable to load configuration file: ${filepath} due to ${error}`, error?.stack);
+        throw new Error('Invalid configuration file');
+      }
+    }
+
+    return this.configCache;
+  }
 }