Legacy environment variables cleanup

[skabashnyuk]

Description

We have quite a lot of environment variable providers that was used in Che6 workspaces that making Che7 plugin configuration complex.
For example, it's very hard to override JAVA_OPTS or MAVEN_OPTS today.
I think we should remove these providers providers

• JavaOptsEnvVariableProvider
• MavenOptsEnvVariableProvider
• WorkspaceAgentCorsAllowCredentialsEnvVarProvider
• WorkspaceAgentCorsAllowedOriginsEnvVarProvider
• WorkspaceAgentCorsEnabledEnvVarProvider
• AgentAuthEnableEnvVarProvider
• WorkspaceAgentJavaOptsEnvVariableProvider

[svor]

Since jdt.ls should be run as a sidecar in Che 7, it would be useful to override JAVA_OPTS.
Also it may help to solve the problem: #12708

[skabashnyuk]

@slemeur @l0rd are you sure we need this for GA? It will introduce some incompatibility with Che6 workspaces.

[l0rd]

@skabashnyuk I am not sure I understand your comment. With Che 7 we are going to break compatibility with Che 6 workspaces. I assumed that it was clear but it looks like it isn't?

[skabashnyuk]

@l0rd
When we decided to remove this classes

JavaOptsEnvVariableProvider
MavenOptsEnvVariableProvider
WorkspaceAgentCorsAllowCredentialsEnvVarProvider
WorkspaceAgentCorsAllowedOriginsEnvVarProvider
WorkspaceAgentCorsEnabledEnvVarProvider
AgentAuthEnableEnvVarProvider
WorkspaceAgentJavaOptsEnvVariableProvider

Che 6 workspaces a likely will not work. So my question is this should happen before or after GA

[l0rd]

I think we can do that as soon as we have removed all Che 6 stacks.

[ibuziuk]

@skabashnyuk looks like I'm facing this problem with spring-rest-guide devfile https://github.com/ibuziuk/my-che-devfiles/tree/master/spring-rest-guide#not-possible-to-override-java_opts-or-maven_opts-in-the-devfile Any ideas if it is possible to override the MAVEN_OPTS somehow?

[metlos]

There is a draft impl provided by @skabashnyuk: #13612

[metlos]

#13612 is ready for review