How we can cancel or pause downloading files using dio?

[Zeeshan0201]

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Issue Info

Info	Value
Platform Name	e.g. flutter / ios / android
Platform Version	e.g. 1.5.0 / 12.0 / 9.0
Dio Version	e.g. 2.1.0 / 1.0.17
Android Studio / Xcode Version	e.g. Android Studio 3.3.2 / Xcode 10.2.1
Repro rate	e.g. all the time (100%) / sometimes x% / only once
Repro with our demo prj	e.g. does it happen with our demo project?
Demo project link	e.g. link to a demo project that highlights the issue

Issue Description and Steps

Please fill in the detailed description of the issue (full output of any stack trace, compiler error, ...) and the steps to reproduce the issue.

[sokryptk]

CancelToken cancelToken = CancelToken;

dio.download(
    cancelToken: cancelToken,
);

Now from anywhere just,
cancelToken.cancel()

As for pause/resume support, better wait for @wendux.

EDIT:

Actually, pause/resume also works, but you have to supply the header range:1222-19238, then append the files.
This downloads the file where you left off at (you will have to calculate the downloaded file size)

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. If this is still an issue, please make sure it is up to date and if so, add a comment that this is still an issue to keep it open. Thank you for your contributions.

[kareemX]

Have you found a solution?

[deepashree-ballodi]

How we can Pause and continue downloading where we stopped exactly?

[sokryptk]

yes

…

On Tue, Aug 4, 2020 at 11:58 AM Deepashree ***@***.***> wrote: How we can Pause and continue downloading where we stopped exactly? — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#399 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AG42GYF4FGMRWJGVTITZHDLR66TBZANCNFSM4II2RAXQ> .

[4-alok]

+1

[sokryptk]

Edited my original comment.

[Omi231]

Edited my original comment.

Can you explain in a bit more detail for noobs like me? Thanks

[mikezander]

@krypticallusion

EDIT:

Actually, pause/resume also works, but you have to supply the header range:1222-19238, then append the files.
This downloads the file where you left off at (you will have to calculate the downloaded file size)

Can you give a simple example? What do you mean by append the files?

[sokryptk]

@krypticallusion

EDIT:

Actually, pause/resume also works, but you have to supply the header range:1222-19238, then append the files. This downloads the file where you left off at (you will have to calculate the downloaded file size)

Can you give a simple example? What do you mean by append the files?

I can't right now give you the exact working sample, sorry.
But here is how it goes :

Z = "The File to be downloaded"

Once you cancel() a download, You should have the file that dio wrote to.
Check the size of the corrupt file.

Issue another download with the range supplied. Suppose you paused the download at 1MB out of 14Mb so (1048576).
Now while calling the download method, supply range:1048576- (No need of the end byte position since you're gonna be downloading the whole thing). Now you have two files, one that has downloaded upto 1048576 bytes while the other file has downloaded from 1048577 to the end of file. Now open the first file with FileMode.APPEND, and write the second file to the first file.

[sokryptk]

https://github.com/flutterchina/dio/blob/develop/example/lib/download_with_trunks.dart

refer this for merging.

[Ahmed-Sellami]

Why doesn't the package offer the possibility to use FileMode.append instead of FileMode.write instead of downloading chunks and then merging them?

dio/dio/lib/src/dio/dio_for_native.dart

Line 89 in 7cfadc4

RandomAccessFile raf = file.openSync(mode: FileMode.write);

[sokryptk]

Why doesn't the package offer the possibility to use FileMode.append instead of FileMode.write instead of downloading chunks and then merging them?

dio/dio/lib/src/dio/dio_for_native.dart

Line 89 in 7cfadc4

RandomAccessFile raf = file.openSync(mode: FileMode.write);

Beats the point, you can't have parallel file writes at the same point in time at different file locations. That's simply not possible. That's why we create some temporary files that can be parallel-ly written to, then stitch them back together. Hope this helps.

[Khushnu]

any solution guys ? for pause and resume ?

[kostov]

@Khushnu,
just read the solution above :)
#399 (comment)
I also starting to implement this.