Reverts hashicorp/nomad#5433
Apparently, channel communications can constitute Happens-Before even for proximate variables, so this syncing isn't necessary.
> _The closing of a channel happens before a receive that returns a zero value because the channel is closed._
https://golang.org/ref/mem#tmp_7
Fix#5418
When using a docker logger that doesn't support log streaming through
API, currently docker logger runs a tight loop of Docker API calls
unexpectedly. This change ensures we stop fetching logs early.
Also, this adds some basic backoff strategy when Docker API logging
fails unexpectedly, to avoid accidentally DoSing the docker daemon.
Noticed that the protobuf files are out of sync with ones generated by 1.2.0 protoc go plugin.
The cause for these files seem to be related to release processes, e.g. [0.9.0-beta1 preperation](ecec3d38de (diff-da4da188ee496377d456025c2eab4e87)), and [0.9.0-beta3 preperation](b849d84f2f).
This restores the changes to that of the pinned protoc version and fails build if protobuf files are out of sync. Sample failing Travis job is that of the first commit change: https://travis-ci.org/hashicorp/nomad/jobs/506285085
strings.Replace call with n=0 argument makes no sense
as it will do nothing. Probably -1 is intended.
Signed-off-by: Iskander Sharipov <quasilyte@gmail.com>
This commit causes the docker driver to return undetected before it
first establishes a connection to the docker daemon.
This fixes a bug where hosts without docker installed would return as
unhealthy, rather than undetected.
As far as I can tell this is the most straightforward and resilient way
to skip error logging on context cancellation with grpc streams. You
cannot compare the error against context.Canceled directly as it is of
type `*status.statusError`. The next best solution I found was:
```go
resp, err := stream.Recv()
if code, ok := err.(interface{ Code() code.Code }); ok {
if code.Code == code.Canceled {
return
}
}
```
However I think checking ctx.Err() directly makes the code much easier
to read and is resilient against grpc API changes.
Currently if a docker_logger cannot be reattached to, we will leak the
container that was being used. This is problematic if e.g using static
ports as it means you can never recover your task, or if a service is
expensive to run and will then be running without supervision.
Sometimes the nomad docker_logger may be killed by a service manager
when restarting the client for upgrades or reliability reasons.
Currently if this happens, we leak the users container and try to
reschedule over it.
This commit adds a new step to the recovery process that will spawn a
new docker logger process that will fetch logs from _the current
timestamp_. This is to avoid restarting users tasks because our logging
sidecar has failed.
* CVE-2019-5736: Update libcontainer depedencies
Libcontainer is vulnerable to a runc container breakout, that was
reported as CVE-2019-5736[1]. Upgrading vendored libcontainer with the fix.
The runc changes are captured in 369b920277 .
[1] https://seclists.org/oss-sec/2019/q1/119
This commit adds some extra resiliency to the docker logger in the case
of API failure from the docker daemon, by restarting the stream from the
current point in time if the stream returns and the container is still
running.
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
Windows Docker daemon does not support SIGINT, SIGTERM is the semantic
equivalent that allows for graceful shutdown before being followed up by
a SIGKILL.
Restore 0.8.x behavior where java driver is marked as detected when
`java -version` exits with 0 but returns unexpected output.
Furthermore, we restore behavior when `java -version` where we parse the
first three lines of `java -version` but ignore rest.
If `java -version` returns less than 3 lines, Nomad 0.8.7 would panic.
In this implementation, we'd still mark java as detected but returns
empty version.
The 0.8.7 logic for detecting java version is found in
https://github.com/hashicorp/nomad/blob/v0.8.7/client/driver/java.go#L132-L172
.
I punt on revamping how we can be more resilient to java -version
syntax, and aimed for preserving existing behavior instead.
