Download a large file via fetch and track ReadableStream progress
It tests streaming I/O and backpressure beyond Promise-based fetch. Acquire a reader from response.body, loop read() until done, sum chunk lengths against Content-Length, and emit progress.
This evaluates your grasp of the Streams API, backpressure, and incremental browser processing to avoid loading massive payloads into memory. First, extract total bytes from the Content-Length header; second, call response.body.getReader() to lock the stream; third, loop reader.read() to receive Uint8Array chunks and accumulate their lengths; fourth, compute progress as received over total and update the UI each iteration; finally, release the lock on completion or error.
Read the original → developer.mozilla.org
- #streams api
- #fetch
- #readablestream
- #typescript
- #web performance
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