Error in Sending Webhooks

[G-Kumaran]

Version :

<dependency>
    <groupId>club.minnced</groupId>
    <artifactId>discord-webhooks</artifactId>
    <version>0.3.2</version>
</dependency>

Environment:
Java 8 with SpringBoot

Code:

WebhookClient.withUrl("https://discordapp.com/api/webhooks/736596600071127061/[REDACTED]")
     .send("Test");

Error:

ERROR 20760 --- [596600071127061] c.minnced.discord.webhook.WebhookClient  : Sending a webhook message failed with non-OK http response

club.minnced.discord.webhook.exception.HttpException: Request returned failure 400: {"code": 50035, "errors": {"allowed_mentions": {"_errors": [{"code": "MODEL_TYPE_CONVERT", "message": "Only dictionaries may be used in a ModelType"}]}}, "message": "Invalid Form Body"}
	at club.minnced.discord.webhook.WebhookClient.failure(WebhookClient.java:375) [discord-webhooks-0.3.2.jar:na]
	at club.minnced.discord.webhook.WebhookClient.executePair(WebhookClient.java:438) [discord-webhooks-0.3.2.jar:na]
	at club.minnced.discord.webhook.WebhookClient.drainQueue(WebhookClient.java:411) [discord-webhooks-0.3.2.jar:na]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[na:1.8.0_252]
	at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[na:1.8.0_252]
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) ~[na:1.8.0_252]
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) ~[na:1.8.0_252]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[na:1.8.0_252]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[na:1.8.0_252]
	at java.lang.Thread.run(Thread.java:748) ~[na:1.8.0_252]

[MinnDevelopment]

I'm unable to reproduce this with your provided code.

[G-Kumaran]

Yeah i received your ping.
But i can consistently reproduce this issue in my code.
Any more debugging info that i can provide to assist you?

[G-Kumaran]

To test Ive manually created a webhook without this api and yet i still get this issue.
So I'm guessing issue isn't in the api...

Damn

[MinnDevelopment]

Potentially this is an issue with your dependencies which somehow conflict with the JSON library?

[G-Kumaran]

You could be right, created a new project with only just the spring-boot-starter and the discord-webhooks dependancies without the any other dependancies. Webhooks now pass.
What json library is discord-webhooks api using? Im on Jackson.

[MinnDevelopment]

This library uses org.json:json:20180813

[kantenkugel]

Jackson shouldn't conflict with org.json though. More likely some of your other dependencies relies on a different version of org.json

[G-Kumaran]

After hours of combination and errors, not able to identify the actual issue.

But found the cause of issue.

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-test</artifactId>
	<scope>test</scope>
</dependency>

Addin this to the pom causes the issue, deleting this from the pom and webhook passes.

Can u reproduce the issue based on this?

[MinnDevelopment]

I don't use maven and have no maven setup but I assume the reason is that maven resolves dependencies on first sight rather than using the latest. The issue might be solved by putting this library as your first dependency.

[G-Kumaran]

Update :
Analysis of packages inside the sping-boot-starter-boot:
This package is causing the issue.

<groupId>org.skyscreamer</groupId>
<artifactId>jsonassert</artifactId>

Source : https://github.com/skyscreamer/JSONassert
Im guessing somthing in this breaks the discord api.

Quick note, this is included in the default https://start.spring.io config.

[MinnDevelopment]

It's likely that some dependency causes a different version of the org.json.JSONObject class to load which can't handle the JSONString interface correctly.

[kantenkugel]

Well i think this issue explains it pretty well: spring-projects/spring-boot#8706

TL;DR: org.skyscreamer:jsonassert depends on com.vaadin.external.google:android-json, which in turn is a "re-implementation" of org.json (using same packages + classes), effectively breaking anything that wants to use actual org.json

[MinnDevelopment]

Then the solution is to exclude this android re-implementation. Closing as resolved.

[G-Kumaran]

Thanks for the explanation @kantenkugel