Do the transformation at config writing time.

src/shadowbox/model/shadowsocks_server.ts

@@ -13,31 +13,14 @@
 // limitations under the License.
 
 // Parameters required to identify and authenticate connections to a Shadowsocks server.
-export interface ShadowsocksServer {
-  // Updates the server to accept only the given service configs.
-  update(config: ShadowsocksConfig): Promise<void>;
-}
-
-/** Represents the overall Shadowsocks configuration with multiple services. */
-export interface ShadowsocksConfig {
-  services: ShadowsocksService[];
-}
-
-/* Represents a Shadowsocks service with its listeners and keys. */
-export interface ShadowsocksService {
-  listeners: ShadowsocksListener[];
-  keys: ShadowsocksAccessKey[];
-}
-
-/* Represents a single listener for a Shadowsocks service. */
-export interface ShadowsocksListener {
-  type: string;
-  address: string;
-}
-
-/* Represents an access key for a Shadowsocks service. */
 export interface ShadowsocksAccessKey {
   id: string;
+  port: number;
   cipher: string;
   secret: string;
 }
+
+export interface ShadowsocksServer {
+  // Updates the server to accept only the given access keys.
+  update(keys: ShadowsocksAccessKey[]): Promise<void>;
+}

src/shadowbox/server/mocks/mocks.ts

@@ -13,7 +13,7 @@
 // limitations under the License.
 
 import {PrometheusClient, QueryResultData} from '../../infrastructure/prometheus_scraper';
-import {ShadowsocksAccessKey, ShadowsocksConfig, ShadowsocksServer} from '../../model/shadowsocks_server';
+import {ShadowsocksAccessKey, ShadowsocksServer} from '../../model/shadowsocks_server';
 import {TextFile} from '../../infrastructure/text_file';
 
 export class InMemoryFile implements TextFile {
@@ -36,17 +36,15 @@ export class InMemoryFile implements TextFile {
 }
 
 export class FakeShadowsocksServer implements ShadowsocksServer {
-  private config: ShadowsocksConfig = {services: []};
+  private accessKeys: ShadowsocksAccessKey[] = [];
 
-  update(config: ShadowsocksConfig) {
-    this.config = config;
+  update(keys: ShadowsocksAccessKey[]) {
+    this.accessKeys = keys;
     return Promise.resolve();
   }
 
-  getAccessKeys(): ShadowsocksAccessKey[] {
-    return this.config.services.reduce((acc, service) => {
-      return acc.concat(service.keys);
-    }, [] as ShadowsocksAccessKey[]);
+  getAccessKeys() {
+    return this.accessKeys;
   }
 }
 

src/shadowbox/server/outline_shadowsocks_server.ts

@@ -19,7 +19,22 @@ import * as path from 'path';
 
 import * as file from '../infrastructure/file';
 import * as logging from '../infrastructure/logging';
-import {ShadowsocksAccessKey, ShadowsocksServer, ShadowsocksConfig} from '../model/shadowsocks_server';
+import {ShadowsocksAccessKey, ShadowsocksServer} from '../model/shadowsocks_server';
+
+/** Represents an outline-ss-server configuration with multiple services. */
+export interface OutlineSSServerConfig {
+  services: {
+    listeners: {
+      type: string;
+      address: string;
+    }[];
+    keys: {
+      id: string;
+      cipher: string;
+      secret: string;
+    }[];
+  }[];
+}
 
 // Runs outline-ss-server.
 export class OutlineShadowsocksServer implements ShadowsocksServer {
@@ -65,10 +80,10 @@ export class OutlineShadowsocksServer implements ShadowsocksServer {
   }
 
   // Promise is resolved after the outline-ss-config config is updated and the SIGHUP sent.
-  // Listeners and keys may not be active yet.
+  // Keys may not be active yet.
   // TODO(fortuna): Make promise resolve when keys are ready.
-  update(config: ShadowsocksConfig): Promise<void> {
-    return this.writeConfigFile(config).then(() => {
+  update(keys: ShadowsocksAccessKey[]): Promise<void> {
+    return this.writeConfigFile(keys).then(() => {
       if (!this.ssProcess) {
         this.start();
         return Promise.resolve();
@@ -78,24 +93,39 @@ export class OutlineShadowsocksServer implements ShadowsocksServer {
     });
   }
 
-  private writeConfigFile(config: ShadowsocksConfig): Promise<void> {
+  private writeConfigFile(keys: ShadowsocksAccessKey[]): Promise<void> {
     return new Promise((resolve, reject) => {
-      for (const service of config.services) {
-        const filteredKeys: ShadowsocksAccessKey[] = [];
-        for (const key of service.keys) {
-          if (!isAeadCipher(key.cipher)) {
-            logging.error(
-              `Cipher ${key.cipher} for access key ${key.id} is not supported: use an AEAD cipher instead.`
-            );
-            continue;
-          }
-          filteredKeys.push(key);
+      const validKeys: ShadowsocksAccessKey[] = keys.filter((key) => {
+        if (!isAeadCipher(key.cipher)) {
+          logging.error(
+            `Cipher ${key.cipher} for access key ${key.id} is not supported: use an AEAD cipher instead.`
+          );
+          return false;
         }
-        service.keys = filteredKeys;
+        return true;
+      });
+
+      const config: OutlineSSServerConfig = {services: []};
+      const keysByPort: Record<number, ShadowsocksAccessKey[]> = {};
+      for (const key of validKeys) {
+        (keysByPort[key.port] ??= []).push(key);
+      }
+      for (const port in keysByPort) {
+        const service = {
+          listeners: [
+            {type: 'tcp', address: `[::]:${port}`},
+            {type: 'udp', address: `[::]:${port}`},
+          ],
+          keys: keysByPort[port].map((key) => ({
+            id: key.id,
+            cipher: key.cipher,
+            secret: key.secret,
+          })),
+        };
+        config.services.push(service);
       }
 
       mkdirp.sync(path.dirname(this.configFilename));
-
       try {
         file.atomicWriteFileSync(this.configFilename, jsyaml.safeDump(config, {sortKeys: true}));
         resolve();

src/shadowbox/server/server_access_key.ts

@@ -28,7 +28,7 @@ import {
   ProxyParams,
 } from '../model/access_key';
 import * as errors from '../model/errors';
-import {ShadowsocksConfig, ShadowsocksServer, ShadowsocksService} from '../model/shadowsocks_server';
+import {ShadowsocksServer} from '../model/shadowsocks_server';
 import {PrometheusManagerMetrics} from './manager_metrics';
 
 // The format as json of access keys in the config file.
@@ -322,34 +322,17 @@ export class ServerAccessKeyRepository implements AccessKeyRepository {
   }
 
   private updateServer(): Promise<void> {
-    const config: ShadowsocksConfig = {services: []}
-
-    // Group access keys by port.
-    const keysByPort = this.accessKeys
+    const serverAccessKeys = this.accessKeys
       .filter((key) => !key.reachedDataLimit)
-      .reduce((acc, key) => {
-        const port = key.proxyParams.portNumber;
-        (acc[port] ??= []).push(key);
-        return acc;
-      }, {} as Record<number, typeof this.accessKeys>);
-
-    // Create services for each port.
-    for (const port in keysByPort) {
-      const service: ShadowsocksService = {
-        listeners: [
-          { type: 'tcp', address: `[::]:${port}` },
-          { type: 'udp', address: `[::]:${port}` },
-        ],
-        keys: keysByPort[port].map((key) => ({
+      .map((key) => {
+        return {
           id: key.id,
+          port: key.proxyParams.portNumber,
           cipher: key.proxyParams.encryptionMethod,
           secret: key.proxyParams.password,
-        })),
-      };
-      config.services.push(service);
-    }
-
-    return this.shadowsocksServer.update(config);
+        };
+      });
+    return this.shadowsocksServer.update(serverAccessKeys);
   }
 
   private loadAccessKeys(): AccessKey[] {