Creating a Parse.File with base64 string fails

[Fouadktb]

New Issue Checklist

• I am not disclosing a vulnerability.
• I am not just asking a question.
• I have searched through existing issues.
• I can reproduce the issue with the latest versions of Parse Server and the Parse JS SDK.

Issue Description

When Calling new Parse.File with the versions 3.4.1 upwards the process takes a few mins then actually throws an error saying
"Cannot create a Parse.File without valid data URIs or base64 encoded data."

Steps to reproduce

Calling Parse.file with the file blob will reproduce the issue

Actual Outcome

an error gets thrown saying: "Cannot create a Parse.File without valid data URIs or base64 encoded data."

Expected Outcome

getting a Parse File back

Environment

not a server issue but =>

Server

• Parse Server version: n/a
• Operating system: n/a
• Local or remote host (AWS, Azure, Google Cloud, Heroku, Digital Ocean, etc): n/a

Database

• System (MongoDB or Postgres): n/a
• Database version: n/a
• Local or remote host (MongoDB Atlas, mLab, AWS, Azure, Google Cloud, etc): n/a

Client

• Parse JS SDK version: 3.4.3

Logs

[parse-github-assistant]

Thanks for opening this issue!

• 🚀 You can help us to fix this issue faster by opening a pull request with a failing test. See our Contribution Guide for how to make a pull request, or read our New Contributor's Guide if this is your first time contributing.

[mtrezza]

Could you submit a PR with a failing test to reproduce the issue?

[dblythy]

It seems this is the issue that is causing the issues here. Trying to save a Parse File with a base64 string of SGVsbG8gV29ybGQh (Hello World!) fails the regex.

Failing test can be as simple as:

it('can create basic files', async () => {
    const buffer =  Buffer.from('Hello World!');
    const file = new ParseFile('hello.txt', {base64: buffer.toString('base64')}, 'text/plain');  // fails here
    expect(file._source.base64).toBe('SGVsbG8gV29ybGQh');
    expect(file._source.type).toBe('text/plain');
})

The problematic regex is:

/([0-9a-zA-Z+/]{4})*(([0-9a-zA-Z+/]{2}==)|([0-9a-zA-Z+/]{3}=))|^data:([a-zA-Z]+\/[-a-zA-Z0-9+.]+(;[a-z-]+=[a-zA-Z0-9+.-]+)?)?(;base64)?,(([0-9a-zA-Z+/]{4})*(([0-9a-zA-Z+/]{2}==)|([0-9a-zA-Z+/]{3}=)))*$/i

[mtrezza]

Did you find out what the problem is with the regex?

[justinlettau]

@mtrezza Here is a PR with failing unit test: #1517

I believe the issue is related to the required padding characters = in the regex. I have an example here to demonstrate.

[mtrezza]

It seems you are right, but the regex in your example does not seem correct, because we'd still strictly expect padding when encoding a 16 bit group. The issue with the current regex seems to be that it doesn't expect to encode a string that is exactly a multiple of 3:

([0-9a-zA-Z+/]{4})*(([0-9a-zA-Z+/]{2}==)|([0-9a-zA-Z+/]{3}=))

The fixed regex that accounts for that would be:

([0-9a-zA-Z+/]{4})*(([0-9a-zA-Z+/]{2}==)|([0-9a-zA-Z+/]{3}=)|([0-9a-zA-Z+/]{4}))

If we want to be even stricter, we can use the following, because padding assumes a defined set of prefixes:

([0-9a-zA-Z+/]{4})*(([0-9a-zA-Z+/][AQgw]==)|([0-9a-zA-Z+/]{2}[AEIMQUYcgkosw048]=)|([0-9a-zA-Z+/]{4}))

I think we should also make sure that we have tests which encode a string:

• without padding (abc = YWJj)
• with 1 padding (ab -> YWI=)
• with 2 padding (a -> YQ==)

If you could add the regex fix to your PR and add the tests, we should be able to close this issue.

[justinlettau]

@mtrezza Regex updated and unit tests added here, thanks.

[DennisVanAcker1]

issue is still occurring: https://stackoverflow.com/questions/73870210/cannot-create-a-parse-file-without-valid-data-uris-or-base64-encoded-data

[mtrezza]

@DennisVanAcker1 Please make sure you are using the Parse JS SDK version which contains the fix, see #1543. If the issue still exists despite you using the alpha version, please open a new issue.

[DennisVanAcker1]

Will do! thanks again, should have looked into this abit more before posting.