File Upload
Multer, file validation, storage, streaming, S3 integration, file size limits
1Which package to use for handling file uploads in NestJS?
Which package to use for handling file uploads in NestJS?
Answer
NestJS uses Multer via @nestjs/platform-express to handle multipart/form-data uploads. Multer is integrated by default with NestJS Express platform. It provides decorators like @UseInterceptors(FileInterceptor()) to simplify uploads. Express-fileupload and body-parser are not recommended with NestJS.
2How to upload a single file in a NestJS endpoint?
How to upload a single file in a NestJS endpoint?
Answer
FileInterceptor('file') is the decorator for uploading a single file, where 'file' is the form field name. FilesInterceptor is for multiple files from the same field, FileFieldsInterceptor for multiple different fields. @UploadedFile() alone doesn't work without an interceptor.
3How to upload multiple files from the same field in NestJS?
How to upload multiple files from the same field in NestJS?
Answer
FilesInterceptor('files', 10) allows uploading up to 10 files from the 'files' field. The second parameter limits the number of files. FileInterceptor is for a single file, AnyFilesInterceptor for all fields without limit, and multiplying FileInterceptor doesn't work.
How to validate the MIME type of an uploaded file in NestJS?
How to limit an uploaded file size to 5 MB in NestJS?
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