This PR adds the capability of running Connect Native Tasks on Nomad,
particularly when TLS and ACLs are enabled on Consul.
The `connect` stanza now includes a `native` parameter, which can be
set to the name of task that backs the Connect Native Consul service.
There is a new Client configuration parameter for the `consul` stanza
called `share_ssl`. Like `allow_unauthenticated` the default value is
true, but recommended to be disabled in production environments. When
enabled, the Nomad Client's Consul TLS information is shared with
Connect Native tasks through the normal Consul environment variables.
This does NOT include auth or token information.
If Consul ACLs are enabled, Service Identity Tokens are automatically
and injected into the Connect Native task through the CONSUL_HTTP_TOKEN
environment variable.
Any of the automatically set environment variables can be overridden by
the Connect Native task using the `env` stanza.
Fixes#6083
The field names within the structs representing the Connect proxy
definition were not the same (nomad/structs/ vs api/), causing the
values to be lost in translation for the 'nomad job inspect' command.
Since the field names already shipped in v0.11.0 we cannot simply
fix the names. Instead, use the json struct tag on the structs/ structs
to remap the name to match the publicly expose api/ package on json
encoding.
This means existing jobs from v0.11.0 will continue to work, and
the JSON API for job submission will remain backwards compatible.
Before, if the sidecar_service stanza of a connect enabled service
was missing, the job submission would cause a panic in the nomad
agent. Since the panic was happening in the API handler the agent
itself continued running, but this change will the condition more
gracefully.
By fixing the `Copy` method, the API handler now returns the proper
error.
$ nomad job run foo.nomad
Error submitting job: Unexpected response code: 500 (1 error occurred:
* Task group api validation failed: 2 errors occurred:
* Missing tasks for task group
* Task group service validation failed: 1 error occurred:
* Service[0] count-api validation failed: 1 error occurred:
* Consul Connect must be native or use a sidecar service
Part of #6120
Building on the support for enabling connect proxy paths in #7323, this change
adds the ability to configure the 'service.check.expose' flag on group-level
service check definitions for services that are connect-enabled. This is a slight
deviation from the "magic" that Consul provides. With Consul, the 'expose' flag
exists on the connect.proxy stanza, which will then auto-generate expose paths
for every HTTP and gRPC service check associated with that connect-enabled
service.
A first attempt at providing similar magic for Nomad's Consul Connect integration
followed that pattern exactly, as seen in #7396. However, on reviewing the PR
we realized having the `expose` flag on the proxy stanza inseperably ties together
the automatic path generation with every HTTP/gRPC defined on the service. This
makes sense in Consul's context, because a service definition is reasonably
associated with a single "task". With Nomad's group level service definitions
however, there is a reasonable expectation that a service definition is more
abstractly representative of multiple services within the task group. In this
case, one would want to define checks of that service which concretely make HTTP
or gRPC requests to different underlying tasks. Such a model is not possible
with the course `proxy.expose` flag.
Instead, we now have the flag made available within the check definitions themselves.
By making the expose feature resolute to each check, it is possible to have
some HTTP/gRPC checks which make use of the envoy exposed paths, as well as
some HTTP/gRPC checks which make use of some orthongonal port-mapping to do
checks on some other task (or even some other bound port of the same task)
within the task group.
Given this example,
group "server-group" {
network {
mode = "bridge"
port "forchecks" {
to = -1
}
}
service {
name = "myserver"
port = 2000
connect {
sidecar_service {
}
}
check {
name = "mycheck-myserver"
type = "http"
port = "forchecks"
interval = "3s"
timeout = "2s"
method = "GET"
path = "/classic/responder/health"
expose = true
}
}
}
Nomad will automatically inject (via job endpoint mutator) the
extrapolated expose path configuration, i.e.
expose {
path {
path = "/classic/responder/health"
protocol = "http"
local_path_port = 2000
listener_port = "forchecks"
}
}
Documentation is coming in #7440 (needs updating, doing next)
Modifications to the `countdash` examples in https://github.com/hashicorp/demo-consul-101/pull/6
which will make the examples in the documentation actually runnable.
Will add some e2e tests based on the above when it becomes available.
Enable configuration of HTTP and gRPC endpoints which should be exposed by
the Connect sidecar proxy. This changeset is the first "non-magical" pass
that lays the groundwork for enabling Consul service checks for tasks
running in a network namespace because they are Connect-enabled. The changes
here provide for full configuration of the
connect {
sidecar_service {
proxy {
expose {
paths = [{
path = <exposed endpoint>
protocol = <http or grpc>
local_path_port = <local endpoint port>
listener_port = <inbound mesh port>
}, ... ]
}
}
}
stanza. Everything from `expose` and below is new, and partially implements
the precedent set by Consul:
https://www.consul.io/docs/connect/registration/service-registration.html#expose-paths-configuration-reference
Combined with a task-group level network port-mapping in the form:
port "exposeExample" { to = -1 }
it is now possible to "punch a hole" through the network namespace
to a specific HTTP or gRPC path, with the anticipated use case of creating
Consul checks on Connect enabled services.
A future PR may introduce more automagic behavior, where we can do things like
1) auto-fill the 'expose.path.local_path_port' with the default value of the
'service.port' value for task-group level connect-enabled services.
2) automatically generate a port-mapping
3) enable an 'expose.checks' flag which automatically creates exposed endpoints
for every compatible consul service check (http/grpc checks on connect
enabled services).
Fix a bug where consul service definitions would not be updated if changes
were made to the service in the Nomad job. Currently this only fixes the
bug for cases where the fix is a matter of updating consul agent's service
registration. There is related bug where destructive changes are required
(see #6877) which will be fixed in another PR.
The enable_tag_override configuration setting for the parent service is
applied to the sidecar service.
Fixes#6459
Consul provides a feature of Service Definitions where the tags
associated with a service can be modified through the Catalog API,
overriding the value(s) configured in the agent's service configuration.
To enable this feature, the flag enable_tag_override must be configured
in the service definition.
Previously, Nomad did not allow configuring this flag, and thus the default
value of false was used. Now, it is configurable.
Because Nomad itself acts as a state machine around the the service definitions
of the tasks it manages, it's worth describing what happens when this feature
is enabled and why.
Consider the basic case where there is no Nomad, and your service is provided
to consul as a boring JSON file. The ultimate source of truth for the definition
of that service is the file, and is stored in the agent. Later, Consul performs
"anti-entropy" which synchronizes the Catalog (stored only the leaders). Then
with enable_tag_override=true, the tags field is available for "external"
modification through the Catalog API (rather than directly configuring the
service definition file, or using the Agent API). The important observation
is that if the service definition ever changes (i.e. the file is changed &
config reloaded OR the Agent API is used to modify the service), those
"external" tag values are thrown away, and the new service definition is
once again the source of truth.
In the Nomad case, Nomad itself is the source of truth over the Agent in
the same way the JSON file was the source of truth in the example above.
That means any time Nomad sets a new service definition, any externally
configured tags are going to be replaced. When does this happen? Only on
major lifecycle events, for example when a task is modified because of an
updated job spec from the 'nomad job run <existing>' command. Otherwise,
Nomad's periodic re-sync's with Consul will now no longer try to restore
the externally modified tag values (as long as enable_tag_override=true).
Fixes#2057
Without a `LocalServicePort`, Connect services will try to use the
mapped port even when delivering traffic locally. A user can override
this behavior by pinning the port value in the `service` stanza but
this prevents us from using the Consul service name to reach the
service.
This commits configures the Consul proxy with its `LocalServicePort`
and `LocalServiceAddress` fields.
* connect: add unix socket to proxy grpc for envoy
Fixes#6124
Implement a L4 proxy from a unix socket inside a network namespace to
Consul's gRPC endpoint on the host. This allows Envoy to connect to
Consul's xDS configuration API.
* connect: pointer receiver on structs with mutexes
* connect: warn on all proxy errors
* taskenv: add connect upstream env vars + test
* set taskenv upstreams instead of appending
* Update client/taskenv/env.go
Co-Authored-By: Michael Schurter <mschurter@hashicorp.com>
* adds meta object to service in job spec, sends it to consul
* adds tests for service meta
* fix tests
* adds docs
* better hashing for service meta, use helper for copying meta when registering service
* tried to be DRY, but looks like it would be more work to use the
helper function
* nomad: add admission controller framework
* nomad: add admission controller framework and Consul Connect hooks
* run admission controllers before checking permissions
* client: add default node meta for connect configurables
* nomad: remove validateJob func since it has been moved to admission controller
* nomad: use new TaskKind type
* client: use consts for connect sidecar image and log level
* Apply suggestions from code review
Co-Authored-By: Michael Schurter <mschurter@hashicorp.com>
* nomad: add job register test with connect sidecar
* Update nomad/job_endpoint_hooks.go
Co-Authored-By: Michael Schurter <mschurter@hashicorp.com>
* jobspec: breakup parse.go into smaller files
* add sidecar_task parsing to jobspec and api
* jobspec: combine service parsing logic for task and group service stanzas
* api: use slice of ConsulUpstream values instead of pointers
Seth Hoenig