MediaOnlyChannelListener DM failure shouldnt result in an error

[Zabuzard]

The MediaOnlyChannelListener sends DMs to the authors of a message to inform them about the action. Thats totally fine and expected, but failure to DM a user (for example if they blocked DMs), it should not yield to an exception being thrown in the logs:

RestAction queue returned failure: [ErrorResponseException] 50007: Cannot send messages to this user
net.dv8tion.jda.api.exceptions.ContextException
at net.dv8tion.jda.api.exceptions.ContextException.here(ContextException.java:54)
at net.dv8tion.jda.internal.requests.restaction.operator.RestActionOperator.contextWrap(RestActionOperator.java:123)
at net.dv8tion.jda.internal.requests.restaction.operator.FlatMapRestAction.queue(FlatMapRestAction.java:50)
at net.dv8tion.jda.api.requests.RestAction.queue(RestAction.java:572)
at net.dv8tion.jda.api.requests.RestAction.queue(RestAction.java:538)
at org.togetherjava.tjbot.commands.mediaonly.MediaOnlyChannelListener.onMessageReceived(MediaOnlyChannelListener.java:48)
at org.togetherjava.tjbot.commands.system.BotCore.lambda$onMessageReceived$9(BotCore.java:205)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java...

The actual DM sending should probably use mapToResults() and then maybe send a DEBUG level log message:

Even better would be to send a message in the channel that pings the user instead and then delete that message after a minute again. But its also okay to go without that for now.

[java-coding-prodigy]

Am I wrong or can this be easily solved just by adding a RestAction#onFailure call to the chain before queuing?

[Zabuzard]

Yeah. It can be simple: on failure -> send debug log

The problem here would be that the user has no idea what they did wrong. So we could think about sending a message with a ping and deleting that message again in 1-2 minutes.

But Im okay if we just solve the bug for now and do the other thing later 🤷

[java-coding-prodigy]

Yeah. It can be simple: on failure -> send debug log

The problem here would be that the user has no idea what they did wrong. So we could think about sending a message with a ping and deleting that message again in 1-2 minutes.

But Im okay if we just solve the bug for now and do the other thing later 🤷

We could do the ping in channel thing if the DMs are blocked, but that might be counter-intuitive as we could anyway do that by default.