[HOLD for payment 2023-09-06] [$1000] Android - Error attempting to download an attachment

[izarutskaya]

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Action Performed:

1. Open a random report and send an attachment (image, video, etc).
2. If it's an image, click on the image, and when the image opens in full view, click on the download button. If it's a video or a different type of attachment, directly click the download button.
3. Observe the error, and the attachment doesn't download.

Expected Result:

The attachment downloads successfully to the device without an error.

Actual Result:

An error appears, and the attachment does not get downloaded to device.

Workaround:

Unknown

Platforms:

Which of our officially supported platforms is this issue occurring on?

• Android / native
• Android / Chrome
• iOS / native
• iOS / Safari
• MacOS / Chrome / Safari
• MacOS / Desktop

Version Number: v1.3.55-4

Reproducible in staging?: Y

Reproducible in production?: Y

If this was caught during regression testing, add the test name, ID and link from TestRail:

Email or phone of affected tester (no customers):

Logs: https://stackoverflow.com/c/expensify/questions/4856

Notes/Photos/Videos: Any additional supporting documentation

recording_20230808_175024.mp4

Screen.Recording.20230818.173007.New.Expensify.mp4

Expensify/Expensify Issue URL:

Issue reported by: @NajiNazzal

Slack conversation: https://expensify.slack.com/archives/C049HHMV9SM/p1691506774751679

View all open jobs on GitHub

Upwork Automation - Do Not Edit

• Upwork Job URL: https://www.upwork.com/jobs/~01ea72aefb3af1826d
• Upwork Job ID: 1692654340381872128
• Last Price Increase: 2023-08-18
• Automatic offers:
• dukenv0307 | Contributor | 26261011

[melvin-bot]

Triggered auto assignment to @garrettmknight (Bug), see https://stackoverflow.com/c/expensify/questions/14418 for more details.

[melvin-bot]

Bug0 Triage Checklist (Main S/O)

• This "bug" occurs on a supported platform (ensure Platforms in OP are ✅)
• This bug is not a duplicate report (check E/App issues and #expensify-bugs)
  • If it is, comment with a link to the original report, close the issue and add any novel details to the original issue instead
• This bug is reproducible using the reproduction steps in the OP. S/O
  • If the reproduction steps are clear and you're unable to reproduce the bug, check with the reporter and QA first, then close the issue.
  • If the reproduction steps aren't clear and you determine the correct steps, please update the OP.
• This issue is filled out as thoroughly and clearly as possible
  • Pay special attention to the title, results, platforms where the bug occurs, and if the bug happens on staging/production.
• I have reviewed and subscribed to the linked Slack conversation to ensure Slack/Github stay in sync

[garrettmknight]

Confirmed in browserstack

[melvin-bot]

Job added to Upwork: https://www.upwork.com/jobs/~01ea72aefb3af1826d

[melvin-bot]

Current assignee @garrettmknight is eligible for the External assigner, not assigning anyone new.

[melvin-bot]

Triggered auto assignment to Contributor-plus team member for initial proposal review - @burczu (External)

[rayane-d]

Proposal

Please re-state the problem that we are trying to solve in this issue.

Our application, designed to save files to the "Downloads/Expensify" directory, is experiencing challenges on Android 11+ devices. Specifically, the application struggles to fetch and store the intended files in the Downloads/Expensify directory.

What is the root cause of that problem?

The introduction of Scoped Storage in Android 11 is the primary factor behind this challenge. This feature:

• Enforces stricter access controls to shared storage areas.
• Prioritizes user privacy by restricting applications from having broad access to the file system.
• Mandates applications to use certain APIs, such as MediaStore, for specific storage operations, particularly when accessing shared storage areas like the Downloads directory.

In our existing implementation, we use the RNFetchBlob library to download the file from the attachement URL and save it to the specified path, here:

App/src/libs/fileDownload/index.android.js

Lines 52 to 61 in 03cf0b1

	// Fetching the attachment
	fetchedAttachment = RNFetchBlob.config({
	fileCache: true,
	path: `${path}/${attachmentName}`,
	addAndroidDownloads: {
	useDownloadManager: true,
	notification: false,
	path: `${path}/Expensify/${attachmentName}`,
	},
	}).fetch('GET', url);

when we set a path and enable addAndroidDownloads with useDownloadManager: true, the RNFetchBlob library attempts to employ the Android Download Manager to fetch and directly store the file in the Downloads directory. However, from Android 11 onwards, designating a custom path for the Download Manager especially paths outside of the app's specific directory will result in failures, all thanks to Scoped Storage restrictions.

What changes do you think we should make in order to solve the problem?

Adapt to the Scoped Storage Model by Modifying RNFetchBlob Configuration:
Exclude the custom path instructions and the addAndroidDownloads configurations from our RNFetchBlob configuration by removing this lines:

App/src/libs/fileDownload/index.android.js

Lines 55 to 60 in 03cf0b1

	path: `${path}/${attachmentName}`,
	addAndroidDownloads: {
	useDownloadManager: true,
	notification: false,
	path: `${path}/Expensify/${attachmentName}`,
	},

As a result, the library will inherently fetch and store the file within the application's specific directory, ensuring alignment with Scoped Storage guidelines.

We have already an Integration with the MediaStore API in the rest of the code:
After the file is fetched within the application's directory, we use RNFetchBlob.MediaCollection.copyToMediaStore to save the file in the Downloads directory.

App/src/libs/fileDownload/index.android.js

Lines 73 to 81 in 03cf0b1

	return RNFetchBlob.MediaCollection.copyToMediaStore(
	{
	name: attachmentName,
	parentFolder: 'Expensify',
	mimeType: null,
	},
	'Download',
	attachmentPath,
	);

This technique collaborates effectively with the Android MediaStore API, granting the application the capability to transfer the file to the Downloads shared directory, without contravening Scoped Storage policies.

Result:

Download.File.mp4

What alternative solutions did you explore? (Optional)

N/A

[rayane-d]

@burczu please review my proposal