Adding Twitter.gs

[choraria]

Makes use of Twitter API v2 along with OAuth 2.0 for Making requests on behalf of users — https://developer.twitter.com/en/docs/authentication/oauth-2-0/user-access-token

[sqrrrl]

If supplying PKCE parameters, would be better to show how to do it properly.

• the code_challenge_method should be S256. Plaintext is much weaker.
• the code_challenge value should be a the base64 encoded sha256 hash of a randomly generated value
• The raw challenge value needs to be durable so it can be provided in the auth callback

Granted, PKCE is meant more for public clients that can't keep secrets, so less of an issue for apps script. Also we may want to see if we can just build PKCE support into the library itself since it's standardized.

[choraria]

@sqrrrl — was able to accommodate the following changes:

• changed code_challenge_method from plain to S256
• the code_challenge value is now a base64 encoded sha256 hash of a randomly generated value

[sqrrrl]

https://developers.google.com/apps-script/reference/utilities/utilities#base64EncodeWebSafe(Byte)

[choraria]

@sqrrrl — tried Utilities.base64EncodeWebSafe but it still ended up creating an = at the end 😕

Figured it might be best to adapt the snippet from the official docs —

You can try meddling with just the PKCE parts using this script — I wrote a small post about it too 😅

[sqrrrl]

Padding is allowed in websafe base64, but looks like twitter is particularly sensitive to it :(