React-native fs stops other async functions to execute until the file downloads

[codesinghanoop]

I am using react-native fs to download the file. The react-native fs uses promises, so until the promise is returned back it keeps other async functions in a queue to execute. For instance, If i start downloading a file then other async functions(such as getting data from local storage) gets blocked. The other async function starts executing only when the download is complete.

any help would be appreciated.

[codesinghanoop]

I found the solution to the issue, Adding few code to the android files will solve the above issue. I made new thread

[codesinghanoop]

can i contribute?

[johanneslumpe]

@codesinghanoop Feel free to! I cannot devote any time to this project at the moment but maybe @cjdell or other contributors can take a look at your PR.

[codesinghanoop]

@johanneslumpe @cjdell I have sent you the pull request, please go through it.

[aengl]

@codesinghanoop Had the same problem and tried your PR. Works like a charm! Thank you.

[codesinghanoop]

No problem friend. @johanneslumpe @cjdell please review my PR, it's helpful.

[br4nnigan]

is it possible that currently downloads block each other in that manner? That means only one download at a time. I have this impression but will investigate further.

[codesinghanoop]

No two parallel download will work. Second download will proceed after first download is done successfully.....

[itinance]

maybe we should start each download task in a separate thread? For android there is already a PR from @codesinghanoop https://github.com/itinance/react-native-fs/pull/254

[codesinghanoop]

@itinance Thanks for the reference sir..

[itinance]

If we would parallelize all download task with next release, some apps could get in trouble than maybe. For keeping backward compat i would suggest to add an optional separateThread-Mode. If this is true, the downloadTask would start in a separate thread, otherwise not.

[codesinghanoop]

Yes that's a good idea...

[codesinghanoop]

Hi guys, According to me we have to add a new thread to write(download) the file and my research says that would not affect other things. We are basically adding thread only for writing(downloading) the files.

[itinance]

And you use the code of your PR for this, right? https://github.com/itinance/react-native-fs/pull/254 Then i will speed it up in upcoming days to test and merge

[codesinghanoop]

Yes, sir right..

[itinance]

Ok thank you! I will do the same on iOS side and merge it then together with your PR. Tomorrow or on Monday.

[codesinghanoop]

cool :+1:

[itinance]

I will merge this in upcoming days, together with a solution for iOS also by my own. Thought i could do this much faster but it will take some days.

[codesinghanoop]

Yeah, no problem ..Thank you :)

[anshul-kai]

Hi guys! Thanks for the research around this. It would be great to parallelize downloads.

@itinance, why do you think that parallelizing may cause issues on some devices?

[itinance]

Because multithreading is often a pain to debug. Also we don't know if any apps would come into trouble when downloads now would be run in parallel. But for next release i will add a note that we've changed the Download-Task to Threads now. /cc @a-koka

Anyway I just merged #254 for android. Need to do this also for iOS or someone wants to send a PR for it?

[zoecarver]

@itinance Has this been released yet? I am having the same issue when I use the react-native-fs npm module.

[codesinghanoop]

is it for iOS or Android ?

[zoecarver]

Android for now (but I am hoping to include iOS later)

[codesinghanoop]

I'm assuming you are using current version of this lib. Please can you install v2.5 and let me know if you are still facing the same issue.

[zoecarver]

That fixed it! Thank you so much! Why is this not in the current version?

[codesinghanoop]

i don't know or may be some new functionality is destroying this. @itinance