[android] [image-manipulator] change base64 encoding options to match with other platforms

[jarvisluong]

This will also affect other modules which produces base64 output as well (camera, file system, ...)

🐛 Bug Report

The base64 output from Android and iOS for the method ImageManipulator.manipulateAsync does not match given the same image.

The output does not necessary need to be exactly matched, but the way base64 output is created currently not matched. When I look at the source code of expo-image-manipulator, on Android, the output is produced by:

expo/packages/expo-image-manipulator/android/src/main/java/expo/modules/imagemanipulator/ImageManipulatorModule.java

Line 157 in 112256a

base64String = Base64.encodeToString(byteOut.toByteArray(), Base64.DEFAULT);

This option (Base64.DEFAULT) will produce a base64 result which will inject line termination character every 74 (maybe?) character.

on iOS:

expo/packages/expo-image-manipulator/ios/EXImageManipulator/EXImageManipulatorModule.m

Line 266 in 112256a

response[@"base64"] = [imageData base64EncodedStringWithOptions:0];

):

This option will produce a base64 result which will be a long line (without line terminators)

and on web:

expo/packages/expo-image-manipulator/src/ExpoImageManipulator.web.ts

Line 199 in 112256a

base64 = canvas.toDataURL('image/' + format, quality);

This method will produce a base64 result which will be a long line (without line terminators)

What we can do is to change the option on Android into:

Base64.encodeToString(byteOut.toByteArray(), Base64.NO_WRAP)

(reference:

1. https://developer.android.com/reference/android/util/Base64#NO_WRAP
2. https://stackoverflow.com/questions/32935783/java-different-results-when-decoding-base64-string-with-java-util-base64-vs-and
   )

Environment

Steps to Reproduce

Here is a minimal snack: https://snack.expo.io/@bankify_expo_admin/085b26

Expected Behavior

The base64 output should be the same given the same image

Actual Behavior

Reproducible Demo

[cruzach]

Thanks for the excellent bug report @jarvisluong ! I agree that this should be consistent across all platforms

Would you like to open a PR for this change?

[jarvisluong]

@cruzach Definitely, Should we change the base64 encoding for FileSystem and Camera as well?

[cruzach]

Seems like you aren't the only one who's discovered this so that may be a good idea. I'm not sure if this would then be considered a breaking change though

[jarvisluong]

I see that in FileSystem the encoding method is already using .NO_WRAP as here:

expo/packages/expo-file-system/android/src/main/java/expo/modules/filesystem/FileSystemModule.java

Line 248 in 0ed80a9

contents = Base64.encodeToString(buffer, 0, bytesRead, Base64.NO_WRAP);

So yes, bringing existing decoders to be the same option would be a good idea!

[cruzach]

thanks @jarvisluong ! closed in #7841