Inconsistent agent options

[dubinsky]

There are many settings that can be set on contexts:

• AGENT_INJECT_TIMEOUT
• AGENT_URL
• DOTFILES_SCRIPT
• DOTFILES_URL
• EXIT_AFTER_TIMEOUT
• GIT_SSH_SIGNATURE_FORWARDING
• GPG_AGENT_FORWARDING
• REGISTRY_CACHE
• SSH_ADD_PRIVATE_KEYS
• SSH_AGENT_FORWARDING
• SSH_CONFIG_INCLUDE_PATH
• SSH_CONFIG_PATH
• SSH_INJECT_DOCKER_CREDENTIALS
• SSH_INJECT_GIT_CREDENTIALS
• SSH_STRICT_HOST_KEY_CHECKING
• TELEMETRY

Unlike all the other injection/forwarding-controlling options, GPG_AGENT_FORWARDING option defaults to false; unless there is a reason not, I suggest that its default be changed to true.

There are four agent options that seem to be common between providers; in my opinion, all of them should be moved from provider to context:

• AGENT_PATH
• INACTIVITY_TIMEOUT
• INJECT_DOCKER_CREDENTIALS
• INJECT_GIT_CREDENTIALS

1. If context option SSH_INJECT_DOCKER_CREDENTIALS did the same as the provider option INJECT_DOCKER_CREDENTIALS (and I don't see it doing anything), it should at a minimum be named the same; but I think it should be removed from the providers altogether, and managed on the context level.
2. If context option SSH_INJECT_GIT_CREDENTIALS did the same as the provider option INJECT_GIT_CREDENTIALS (and I don't see it doing anything), it should at a minimum be named the same; but I think it should be removed from the providers altogether, and managed on the context level.
3. AGENT_PATH should be moved from providers to context.
4. INACTIVITY_TIMEOUT should be moved from providers to context.

[skevetter]

GPG_AGENT_FORWARDING option defaults to false; unless there is a reason not, I suggest that its default be changed to true.

The client may not have gnupg installed in their container. So no, in my opinion, the default value for GPG_AGENT_FORWARDING should remain false as this reduces the number of container failures. I may consider detecting the presence of gnupg and issuing a warning to the user that gnupg is not present to provide visibility. Although, the user may intentionally define the container in such a way that it installs gnupg as various points (pre-, during, post-creation). In this case, the interaction is not idempotent.

I will follow up with the rest of the options after doing some more research.