Pulling large docker containers can take longer than the default
context timeout. Without a way to change this it is very hard for
users to utilise Nomad properly without hacky work arounds.
This change adds an optional pull_timeout config parameter which
gives operators the possibility to account for increase pull times
where needed. The infra docker image also has the option to set a
custom timeout to keep consistency.
This fixes few cases where driver eventor goroutines are leaked during
normal operations, but especially so in tests.
This change makes few modifications:
First, it switches drivers to use `Context`s to manage shutdown events.
Previously, it relied on callers invoking `.Shutdown()` function that is
specific to internal drivers only and require casting. Using `Contexts`
provide a consistent idiomatic way to manage lifecycle for both internal
and external drivers.
Also, I discovered few places where we don't clean up a temporary driver
instance in the plugin catalog code, where we dispense a driver to
inspect and validate the schema config without properly cleaning it up.
The plugin loader supplies a version map to ensure the Nomad agent
can support the plugins at the version they specify. The map was
incorrectly mapping the driver type to the device API supported
version identifier. This currently does not cause a bug as both
device and driver versions are the same string. This could cause
problems in the future, however, if either plugin interface were
to change and require version updates.
nvidia library use of dynamic library seems to conflict with alpine and
musl based OSes. This adds a `nonvidia` tag to allow compiling nomad
for alpine images.
The nomad releases currently only support glibc based OS environments,
so we default to compiling with nvidia.
This ensures that `port_map` along with other block like attribute
declarations (e.g. ulimit, labels, etc) can handle various hcl and json
syntax that was supported in 0.8.
In 0.8.7, the following declarations are effectively equivalent:
```
// hcl block
port_map {
http = 80
https = 443
}
// hcl assignment
port_map = {
http = 80
https = 443
}
// json single element array of map (default in API response)
{"port_map": [{"http": 80, "https": 443}]}
// json array of individual maps (supported accidentally iiuc)
{"port_map: [{"http": 80}, {"https": 443}]}
```
We achieve compatbility by using `NewAttr("...", "list(map(string))",
false)` to be serialized to a `map[string]string` wrapper, instead of using
`BlockAttrs` declaration. The wrapper merges the list of maps
automatically, to ease driver development.
This approach is closer to how v0.8.7 implemented the fields [1][2], and
despite its verbosity, seems to perserve 0.8.7 behavior in hcl2.
This is only required for built-in types that have backward
compatibility constraints. External drivers should use `BlockAttrs`
instead, as they see fit.
[1] https://github.com/hashicorp/nomad/blob/v0.8.7/client/driver/docker.go#L216
[2] https://github.com/hashicorp/nomad/blob/v0.8.7/client/driver/docker.go#L698-L700
The test used old local copies of Docker structs and appeared to be
testing an outdated approach to task config decoding.
Updated to use real Docker structs so we can do end-to-end unit testing
of real Docker task configs.