NestJS · Senior · Question 53 of 75

How do you stream a large file download in Nest without loading it into memory?

1Read the file with readFileSync and return the Buffer
2Base64-encode it in JSON
✓Correct answer: Return a StreamableFile wrapping a readable stream, so Nest pipes it to the response

Explanation

StreamableFile works with both Express and Fastify and keeps interceptors working.

Further reading

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