open-nomad/client/consul/consul.go
Seth Hoenig ed13e5723f consul/connect: dynamically select envoy sidecar at runtime
As newer versions of Consul are released, the minimum version of Envoy
it supports as a sidecar proxy also gets bumped. Starting with the upcoming
Consul v1.9.X series, Envoy v1.11.X will no longer be supported. Current
versions of Nomad hardcode a version of Envoy v1.11.2 to be used as the
default implementation of Connect sidecar proxy.

This PR introduces a change such that each Nomad Client will query its
local Consul for a list of Envoy proxies that it supports (https://github.com/hashicorp/consul/pull/8545)
and then launch the Connect sidecar proxy task using the latest supported version
of Envoy. If the `SupportedProxies` API component is not available from
Consul, Nomad will fallback to the old version of Envoy supported by old
versions of Consul.

Setting the meta configuration option `meta.connect.sidecar_image` or
setting the `connect.sidecar_task` stanza will take precedence as is
the current behavior for sidecar proxies.

Setting the meta configuration option `meta.connect.gateway_image`
will take precedence as is the current behavior for connect gateways.

`meta.connect.sidecar_image` and `meta.connect.gateway_image` may make
use of the special `${NOMAD_envoy_version}` variable interpolation, which
resolves to the newest version of Envoy supported by the Consul agent.

Addresses #8585 #7665
2020-10-13 09:14:12 -05:00

53 lines
1.8 KiB
Go

package consul
import (
"github.com/hashicorp/nomad/command/agent/consul"
"github.com/hashicorp/nomad/nomad/structs"
)
// ConsulServiceAPI is the interface the Nomad Client uses to register and
// remove services and checks from Consul.
//
// ACL requirements
// - service:write
type ConsulServiceAPI interface {
// RegisterWorkload with Consul. Adds all service entries and checks to Consul.
RegisterWorkload(*consul.WorkloadServices) error
// RemoveWorkload from Consul. Removes all service entries and checks.
RemoveWorkload(*consul.WorkloadServices)
// UpdateWorkload in Consul. Does not alter the service if only checks have
// changed.
UpdateWorkload(old, newTask *consul.WorkloadServices) error
// AllocRegistrations returns the registrations for the given allocation.
AllocRegistrations(allocID string) (*consul.AllocRegistration, error)
// UpdateTTL is used to update the TTL of a check.
UpdateTTL(id, output, status string) error
}
// TokenDeriverFunc takes an allocation and a set of tasks and derives a
// service identity token for each. Requests go through nomad server.
type TokenDeriverFunc func(*structs.Allocation, []string) (map[string]string, error)
// ServiceIdentityAPI is the interface the Nomad Client uses to request Consul
// Service Identity tokens through Nomad Server.
//
// ACL requirements
// - acl:write (used by Server only)
type ServiceIdentityAPI interface {
// DeriveSITokens contacts the nomad server and requests consul service
// identity tokens be generated for tasks in the allocation.
DeriveSITokens(alloc *structs.Allocation, tasks []string) (map[string]string, error)
}
// SupportedProxiesAPI is the interface the Nomad Client uses to request from
// Consul the set of supported proxied to use for Consul Connect.
//
// No ACL requirements
type SupportedProxiesAPI interface {
Proxies() (map[string][]string, error)
}