Embed fields such as author icon are considered non-optional

[marvin-roesch]

I have encountered a bug in Discord4J that appears to have been introduced with the upgrade to 3.1.0. Namely, it concerns (to my knowledge) embeds and their properties:

To Reproduce:

• Generate a message with an embed without e.g. author icon
• Read that message using Discord4J and look at the embed

Expected Behavior:

• Embed.Author#getIconUrl returns an empty Optional<String>, null or similar

Actual Behavior:

• A java.util.NoSuchElementException exception is thrown

Version: 3.1.0

Other: I've only come across the issue with the author icon out in the wild so far, but I'd expect more fields to actually be optional.

[darichey]

There's a few Possible::get() uses in Embed that were overlooked. Ideally they would've been mapped to Optional and the return types would be changed. Not sure what the best course of action is here since 3.1 is released.

[darichey]

quanticc pointed out we can annotate these methods as @Nullable and change the implementation to fallback to null. While we generally try to avoid that in core, I think it's the best option here until 3.2. That was the previous behavior anyways, we just didn't know.

[darichey]

Will be fixed in 3.1.1 with the @Nullable solution and with some incompatible Optional changes in 3.2. If you need the fix before release, you can use a snapshot of either branch.

[marvin-roesch]

Thanks for the speedy solution @darichey! I've worked around the issue for now by manually catching the exception and mapping it to null (which is fine by me, as I'm using it from Kotlin, anyway), so looking forward to the fixed version!