How do you apply an exception filter at the method, controller, and global level in NestJS?

Q: How do you apply an exception filter at the method, controller, and global level in NestJS?

// Method level — narrowest scope @UseFilters(HttpExceptionFilter) @Get(':id') findOne() {} // Controller level — all routes in the class @UseFilters(HttpExceptionFilter) @Controller('users') export class UsersController {} // Global — Option A: outside DI (no injection support) app.useGlobalFilters(new HttpExceptionFilter()); // Global — Option B: APP_FILTER token (preferred, full DI support) @Module({ providers: [ { provide: APP_FILTER, useClass: AllExceptionsFilter }, ], }) export class AppModule {} Resolution order when an exception is thrown: method → controller → global. The first filter whose @Catch() type matches the thrown exception handles it. Pass class reference to @UseFilters(MyFilter) for DI support; pass instance (new MyFilter()) for no-DI cases. app.useGlobalFilters() — simple but cannot inject services. APP_FILTER token — filter is a full NestJS provider with constructor injection.

Difficulty: 5/10

exception filters, NestJS error handling, filter scope

Use @UseFilters() at method or controller level. For global registration use app.useGlobalFilters() (no DI support) or the APP_FILTER token (full DI support, preferred). Passing the class reference to @UseFilters() is preferred over an instance when the filter has dependencies — NestJS resolves it through the DI container.

Filter binding at all three levels

Binding level rules:

1
Resolution order when an exception is thrown: method → controller → global.
2
The first filter whose @Catch() type matches the thrown exception handles it.
3

How do you apply an exception filter at the method, controller, and global level in NestJS?

Difficulty: 5/10

exception filters, NestJS error handling, filter scope

Use @UseFilters() at method or controller level. For global registration use app.useGlobalFilters() (no DI support) or the APP_FILTER token (full DI support, preferred). Passing the class reference to @UseFilters() is preferred over an instance when the filter has dependencies — NestJS resolves it through the DI container.

Filter binding at all three levels

Binding level rules:

1
Resolution order when an exception is thrown: method → controller → global.
2
The first filter whose @Catch() type matches the thrown exception handles it.
3

How do you apply an exception filter at the method, controller, and global level in NestJS?

How do you apply an exception filter at the method, controller, and global level in NestJS?

Scenario Questions

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