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\n\n \n
\n A Nest interceptor to log the incoming/outgoing requests.\n
\n\n# NestJS Logging interceptor\n\nA simple NestJS interceptor catching request details and logging it using the built-in [Logger](https://docs.nestjs.com/techniques/logger#logger) class. It will use the default Logger implementation unless you pass your own to your Nest application.\n\n## Installation\n\n```bash\nnpm install --save @algoan/nestjs-logging-interceptor\n```\n\n## Usage\n### Default usage\nUse the interceptor as a global interceptor (cf. refer to the [last paragraph](https://docs.nestjs.com/interceptors#binding-interceptors) of this section for more details).\n\nExample:\n\n```typescript\nimport { Module } from '@nestjs/common';\nimport { APP_INTERCEPTOR } from '@nestjs/core';\nimport { LoggingInterceptor } from '@algoan/nestjs-logging-interceptor';\n\n/**\n * Core module: This module sets the logging interceptor as a global interceptor\n */\n@Module({\n providers: [\n {\n provide: APP_INTERCEPTOR,\n useClass: LoggingInterceptor,\n },\n ],\n})\nexport class CoreModule {}\n```\n\nIn the example above, the interceptor is provided by the CoreModule. It could be set on any module that your main module is using.\n\n### Factory\nYou can also manually pass an interceptor instance through a factory function. This will give the possibility to set a `userPrefix` on the head of the default context message:\n\nExample:\n\n```typescript\nimport { Module } from '@nestjs/common';\nimport { APP_INTERCEPTOR } from '@nestjs/core';\nimport { LoggingInterceptor } from '@algoan/nestjs-logging-interceptor';\n\n/**\n * Core module: This module sets the logging interceptor as a global interceptor\n */\n@Module({\n providers: [\n {\n provide: APP_INTERCEPTOR,\n useFactory: () => new LoggingInterceptor({ userPrefix: 'ExampleApp'}),\n },\n ],\n})\nexport class CoreModule {}\n```\n\nThe context message will be preprend by the provided `userPrefix`:\n```bash\n[LoggingInterceptor - GET - /error] Incoming request - GET - /error\n==>\n[ExampleApp - LoggingInterceptor - GET - /error] Incoming request - GET - /error\n```\n\n## Log messages\n\nThis interceptor logs:\n - incoming request details\n - outgoing response details\n\n### Default Logger messages\n```bash\n# Incoming request details\n\n# info level\n[Nest] 27080 - 04/06/2020, 10:11:54 AM [LoggingInterceptor - GET - /] Object:\n{\n \"message\": \"LoggingInterceptor - GET - /\",\n \"method\": \"GET\",\n \"body\": {},\n \"headers\": {\n \"host\": \"localhost:3000\",\n \"user-agent\": \"insomnia/7.1.1\",\n \"authorization\": \"Bearer 1234\",\n \"accept\": \"*/*\"\n }\n}\n```\n\n- outgoing request details (info + (debug | warn | error))\n\n```bash\n# Success example\n\n# Info level\n[Nest] 27080 - 04/06/2020, 10:11:54 AM [LoggingInterceptor - 200 - GET - /] Object:\n{\n \"message\": \"LoggingInterceptor - 200 - GET - /\",\n \"body\": \"Hello World!\"\n}\n\n# Warning example\n\n# warn level\n[Nest] 27080 - 04/06/2020, 10:12:44 AM [LoggingInterceptor - 400 - GET - /badrequest] Object:\n{\n \"method\": \"GET\",\n \"url\": \"/badrequest\",\n \"error\": {\n \"response\": {\n \"statusCode\": 400,\n \"message\": \"Bad Request\"\n },\n \"status\": 400,\n \"message\": \"Bad Request\"\n },\n \"body\": {},\n \"message\": \"LoggingInterceptor - 400 - GET - /badrequest\"\n}\n\n# Error example\n\n# error level\n[Nest] 27080 - 04/06/2020, 10:12:17 AM [LoggingInterceptor - 500 - GET - /error] Object:\n{\n \"method\": \"GET\",\n \"url\": \"/error\",\n \"body\": {},\n \"message\": \"LoggingInterceptor - 500 - GET - /error\"\n}\n +2ms\nError: Internal Server Error\n at AppController.error (/Users/philippediep/Documents/workspace/algoan/examples/example-manager/dist/app.controller.js:25:15)\n at /Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/@nestjs/core/router/router-execution-context.js:37:29\n at InterceptorsConsumer.transformDeffered (/Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/@nestjs/core/interceptors/interceptors-consumer.js:30:28)\n at /Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/@nestjs/core/interceptors/interceptors-consumer.js:14:48\n at Observable._subscribe (/Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/rxjs/internal/observable/defer.js:10:21)\n at Observable._trySubscribe (/Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/rxjs/internal/Observable.js:44:25)\n at Observable.subscribe (/Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/rxjs/internal/Observable.js:30:22)\n at Object.subscribeToResult (/Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/rxjs/internal/util/subscribeToResult.js:12:23)\n at MergeMapSubscriber._innerSub (/Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/rxjs/internal/operators/mergeMap.js:82:53)\n at MergeMapSubscriber._tryNext (/Users/philippediep/Documents/workspace/algoan/examples/example-manager/node_modules/rxjs/internal/operators/mergeMap.js:76:14)\n\n```\n\n### Masking\nBy default, the whole body of the request and of the response is logged. However, the payload may contain sensitive data you would like to hide in the logs. The `Log` decorator provides masking options which allow to override the default properties logged for each endpoint. You just need to provide the path of the properties to mask for the request and/or the response. The corresponding values will be replaced by the placeholder `****` in the resulting log.\n\nFor example:\n\n```typescript\nimport { Log } from '@algoan/nestjs-logging-interceptor'\nimport { Body, Controller } from '@nestjs/common';\n\n@Controller('users')\nexport class UsersController {\n\n @Post()\n @Log({\n mask: {\n request: [\n 'lastName', // simple property\n 'maritalSituation', // object property\n 'contact.phone', // nested property\n 'friends.lastName' // property of an array element\n ],\n response: ['lastName'],\n },\n })\n public createUser(@Body() payload: UserDto) {\n // create and return the new user\n }\n}\n```\n\nIf the endpoint is called with:\n```json\n{\n \"firstName\": \"John\",\n \"lastName\": \"Doe\",\n \"maritalSituation\": {\n \"status\": \"MARRIED\",\n \"wife\": { \"firstName\": \"Jane\", \"lastName\": \"Doe\" }\n },\n \"contact\": { \"email\": \"john.doe@email.com\", \"phone\": \"+330102030405\" },\n \"friends\": [\n { \"firstName\": \"James\", \"lastName\": \"Smith\" },\n { \"firstName\": \"Emma\", \"lastName\": \"Cole\" }\n ]\n}\n```\nThe body in the logged request will be:\n```json\n{\n \"firstName\": \"John\",\n \"lastName\": \"****\",\n \"maritalSituation\": \"****\",\n \"contact\": { \"email\": \"john.doe@email.com\", \"phone\": \"****\" },\n \"friends\": [\n { \"firstName\": \"James\", \"lastName\": \"****\" },\n { \"firstName\": \"Emma\", \"lastName\": \"****\" }\n ]\n}\n```\n\nIf you want you to mask the whole body of the request/response, you can pass `true` instead of the array containing the exhaustive list of properties.\n\nIn addition, other options can be set at the interceptor level:\n\n```typescript\nimport { Module } from '@nestjs/common';\nimport { APP_INTERCEPTOR } from '@nestjs/core';\nimport { LoggingInterceptor } from '@algoan/nestjs-logging-interceptor';\n\n@Module({\n providers: [\n {\n provide: APP_INTERCEPTOR,\n useFactory: () =>\n new LoggingInterceptor({\n disableMasking: true, // Ignore masking options in the entire applications\n maskingPlaceholder: 'hidden', // Replace the default placeholder '****' by a custom one\n mask: {\n requestHeader: {\n password: true, // Mask the header 'password' in the request\n authorization: (header: string | string[]) => {\n ... // Handle the header value to keep non sensitive data for instance\n }\n },\n },\n }),\n },\n ],\n})\nexport class CoreModule {}\n```\n\n### Truncation\nBy default, the whole body of the request and of the response is logged. However, the monitoring platform you may use to store and access your logs can have a log size limit being lower than your body request. The `Log` decorator provides truncation options which allow to truncate the default truncation options for each endpoint. You just need to provide the limit. The log of body will be truncated at the limit set or if you have provided a `truncate` function as you have defined it.\n\nFor example:\n\n```typescript\nimport { Log } from '@algoan/nestjs-logging-interceptor'\nimport { Body, Controller } from '@nestjs/common';\n\n@Controller('users')\nexport class UsersController {\n\n @Post()\n @Log({\n truncation: {\n limit: 10000,\n truncate: (body) => ({\n ...body,\n friends: 'TRUNCATED'\n }),\n }\n })\n public createUser(@Body() payload: UserDto) {\n // create and return the new user\n }\n}\n```\n\nIf the endpoint is called with:\n```json\n{\n \"firstName\": \"John\",\n \"lastName\": \"Doe\",\n \"maritalSituation\": {\n \"status\": \"MARRIED\",\n \"wife\": { \"firstName\": \"Jane\", \"lastName\": \"Doe\" }\n },\n \"contact\": { \"email\": \"john.doe@email.com\", \"phone\": \"+330102030405\" },\n \"friends\": [\n { \"firstName\": \"James\", \"lastName\": \"Smith\" },\n { \"firstName\": \"Emma\", \"lastName\": \"Cole\" }\n // ... thousands of other friends\n ]\n}\n```\nThe body in the logged request will be:\n```json\n{\n \"firstName\": \"John\",\n \"lastName\": \"Doe\",\n \"maritalSituation\": {\n \"status\": \"MARRIED\",\n \"wife\": { \"firstName\": \"Jane\", \"lastName\": \"Doe\" }\n },\n \"contact\": { \"email\": \"john.doe@email.com\", \"phone\": \"+330102030405\" },\n \"friends\": \"TRUNCATED\"\n}\n```\n\nWithout the truncate options, it would be converted to a string and cut at the limit.\n\nThe option can also be for all routes at once:\n\n```typescript\nimport { Module } from '@nestjs/common';\nimport { APP_INTERCEPTOR } from '@nestjs/core';\nimport { LoggingInterceptor } from '@algoan/nestjs-logging-interceptor';\n\n@Module({\n providers: [\n {\n provide: APP_INTERCEPTOR,\n useFactory: () =>\n new LoggingInterceptor({\n truncation: {\n limit: 10000\n }\n }),\n },\n ],\n})\nexport class CoreModule {}\n```\n\n\n### Use a custom Logger\n\n#### Nest-pino\n\nIn this example, we are going to override the default Logger implementation with a Pino logger (refer to the [this official NestJS documentation](https://docs.nestjs.com/techniques/logger#using-the-logger-for-application-logging))\n\n```typescript\nimport { Module } from '@nestjs/common';\nimport { CoreModule } from './core/core.module'; // the module importing the @algoan/nestjs-logging-interceptor\nimport { AppController } from './app.controller';\nimport { AppService } from './app.service';\nimport { LoggerModule } from 'nestjs-pino';\n\n@Module({\n imports: [LoggerModule.forRoot(), CoreModule],\n controllers: [AppController],\n providers: [AppService],\n})\nexport class AppModule {}\n```\n\nThen in the application bootstrap, set the [Pino logger](https://github.com/iamolegga/nestjs-pino) as the one to substitute to the default Logger.\n\n```typescript\nimport { NestFactory} from '@nestjs/core';\nimport { Logger } from \"nestjs-pino\";\nimport { MainModule } from './main.module';\n\nasync function bootstrap() {\n const app = await NestFactory.create(MainModule,{\n logger: false\n });\n\n app.useLogger(app.get(Logger))\n await app.listen(3000);\n}\nbootstrap();\n```\n\nThe Pino logger will be set as the Logger implementation to use.\n\n```bash\n# With default Logger\n[Nest] 84392 - 04/03/2020, 2:02:04 PM [RoutesResolver] AppController {}: +7ms\n[Nest] 84392 - 04/03/2020, 2:02:04 PM [RouterExplorer] Mapped {, GET} route +3ms\n[Nest] 84392 - 04/03/2020, 2:02:04 PM [RouterExplorer] Mapped {/badrequest, GET} route +0ms\n[Nest] 84392 - 04/03/2020, 2:02:04 PM [RouterExplorer] Mapped {/error, GET} route +0ms\n[Nest] 84392 - 04/03/2020, 2:02:04 PM [NestApplication] Nest application successfully started +3ms\n\n# With Pino Logger\n{\"level\":30,\"time\":1585915251917,\"pid\":83826,\"hostname\":\"computername.local\",\"context\":\"RoutesResolver\",\"msg\":\"AppController {}: true\",\"v\":1}\n{\"level\":30,\"time\":1585915251919,\"pid\":83826,\"hostname\":\"computername.local\",\"context\":\"RouterExplorer\",\"msg\":\"Mapped {, GET} route true\",\"v\":1}\n{\"level\":30,\"time\":1585915251919,\"pid\":83826,\"hostname\":\"computername.local\",\"context\":\"RouterExplorer\",\"msg\":\"Mapped {/badrequest, GET} route true\",\"v\":1}\n{\"level\":30,\"time\":1585915251919,\"pid\":83826,\"hostname\":\"computername.local\",\"context\":\"RouterExplorer\",\"msg\":\"Mapped {/error, GET} route true\",\"v\":1}\n{\"level\":30,\"time\":1585915251921,\"pid\":83826,\"hostname\":\"computername.local\",\"context\":\"NestApplication\",\"msg\":\"Nest application successfully started true\",\"v\":1}\n```\n","readmeFilename":"README.md"}