Only getting a small segment of the requested body (or 'why is my body 'passthrough?')

[jfederer]

With the following code:

const DigestFetch = require('digest-fetch')
const fs = require('fs')

const user = 'xxx'
const pass = 'xxx'
const uri = 'xxx'

const client = new DigestFetch(user, pass)

options = {}

async function doFetch() {
	client.fetch(uri, options)
		.then(async resp => {
			console.log('resp.body :>> ', resp.body);
			const filename = "picture.jpg"
			const fileContents = Buffer.from(resp.body._readableState.buffer.head.data, 'base64')
			console.log('fileContents :>> ', fileContents); // outputs a buffer that's about 1k in size
			fs.writeFile(filename, fileContents, (err) => {
				if (err) return console.error(err)
				console.log('file saved to ', filename)
				return resp.body
			})

		})
		.catch(err => console.log('err :>> ', err));
}

doFetch()

resp.body is:

PassThrough {
_readableState: ReadableState {
objectMode: false,
highWaterMark: 16384,
buffer: BufferList { head: [Object], tail: [Object], length: 1 },
length: 920,
pipes: [],
flowing: null,
ended: false,
endEmitted: false,
reading: true,
constructed: true,
sync: false,
needReadable: true,
emittedReadable: false,
readableListening: false,
resumeScheduled: false,
errorEmitted: false,
emitClose: true,
autoDestroy: true,
destroyed: false,
errored: null,
closed: false,
closeEmitted: false,
defaultEncoding: 'utf8',
awaitDrainWriters: null,
multiAwaitDrain: false,
readingMore: false,
dataEmitted: false,
decoder: null,
encoding: null,
[Symbol(kPaused)]: null
},
_events: [Object: null prototype] {
prefinish: [Function: prefinish],
unpipe: [Function: onunpipe],
error: [ [Function: onerror], [Function (anonymous)] ],
close: [Function: bound onceWrapper] { listener: [Function: onclose] },
finish: [Function: bound onceWrapper] { listener: [Function: onfinish] }
},
_eventsCount: 5,
_maxListeners: undefined,
_writableState: WritableState {
objectMode: false,
highWaterMark: 16384,
finalCalled: false,
needDrain: false,
ending: false,
ended: false,
finished: false,
destroyed: false,
decodeStrings: true,
defaultEncoding: 'utf8',
length: 0,
writing: false,
corked: 0,
sync: false,
bufferProcessing: false,
onwrite: [Function: bound onwrite],
writecb: null,
writelen: 0,
afterWriteTickInfo: null,
buffered: [],
bufferedIndex: 0,
allBuffers: true,
allNoop: true,
pendingcb: 0,
constructed: true,
prefinished: false,
errorEmitted: false,
emitClose: true,
autoDestroy: true,
errored: null,
closed: false,
closeEmitted: false,
[Symbol(kOnFinished)]: []
},
allowHalfOpen: true,
[Symbol(kCapture)]: false,
[Symbol(kCallback)]: null
}

I was expecting resp.body to return the image (as a buffer, likely)

When I dig into the resp.body Passthrough object, I get a buffer in the _readableState.buffer.head.data area... but it seems to only be 1k. ... which makes sense, as this code gives me a 1k image that only has the first few pixels.

How to do ensure the connection provides the entire image?

[devfans]

digest-fetch only wraps around fetch/node-fetch, it does not touch the response body, please check the fetch/node-fetch documentation to get the full response data.

[devfans]

node-fetch/node-fetch#147 might be useful for you

[jfederer]

Thank you. I'll investigate through there.