backend-app-api: move global loggers and winston helper back to backend-common

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

packages/backend-common/src/logging/globalLoggers.ts

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2020 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import * as winston from 'winston';
+
+/**
+ * A logger that just throws away all messages.
+ *
+ * @public
+ */
+export function getVoidLogger(): winston.Logger {
+  return winston.createLogger({
+    transports: [new winston.transports.Console({ silent: true })],
+  });
+}
+
+let rootLogger: winston.Logger = createRootLogger();
+
+/**
+ * Gets the current root logger.
+ *
+ * @public
+ */
+export function getRootLogger(): winston.Logger {
+  return rootLogger;
+}
+
+/**
+ * Sets a completely custom default "root" logger.
+ *
+ * @remarks
+ *
+ * This is the logger instance that will be the foundation for all other logger
+ * instances passed to plugins etc, in a given backend.
+ *
+ * Only use this if you absolutely need to make a completely custom logger.
+ * Normally if you want to make light adaptations to the default logger
+ * behavior, you would instead call {@link createRootLogger}.
+ *
+ * @public
+ */
+export function setRootLogger(newLogger: winston.Logger) {
+  rootLogger = newLogger;
+}

packages/backend-common/src/logging/index.ts

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2020 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+export { getRootLogger, getVoidLogger, setRootLogger } from './globalLoggers';
+export { loggerToWinstonLogger } from './loggerToWinstonLogger';

packages/backend-common/src/logging/loggerToWinstonLogger.ts

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2022 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { LoggerService } from '@backstage/backend-plugin-api';
+import { Logger as WinstonLogger, createLogger } from 'winston';
+import Transport, { TransportStreamOptions } from 'winston-transport';
+
+class BackstageLoggerTransport extends Transport {
+  constructor(
+    private readonly backstageLogger: LoggerService,
+    opts?: TransportStreamOptions,
+  ) {
+    super(opts);
+  }
+
+  log(info: unknown, callback: VoidFunction) {
+    if (typeof info !== 'object' || info === null) {
+      callback();
+      return;
+    }
+    const { level, message, ...meta } = info as { [name: string]: unknown };
+    switch (level) {
+      case 'error':
+        this.backstageLogger.error(String(message), meta);
+        break;
+      case 'warn':
+        this.backstageLogger.warn(String(message), meta);
+        break;
+      case 'info':
+        this.backstageLogger.info(String(message), meta);
+        break;
+      case 'debug':
+        this.backstageLogger.debug(String(message), meta);
+        break;
+      default:
+        this.backstageLogger.info(String(message), meta);
+    }
+    callback();
+  }
+}
+
+/** @public */
+export function loggerToWinstonLogger(
+  logger: LoggerService,
+  opts?: TransportStreamOptions,
+): WinstonLogger {
+  return createLogger({
+    transports: [new BackstageLoggerTransport(logger, opts)],
+  });
+}

packages/backend-common/src/tokens/ServerTokenManager.test.ts

@@ -16,7 +16,7 @@
 
 import { ConfigReader } from '@backstage/config';
 import * as jose from 'jose';
-import { getVoidLogger } from '../logging/voidLogger';
+import { getVoidLogger } from '../logging';
 import { ServerTokenManager } from './ServerTokenManager';
 import { TokenManager } from './types';