open-nomad/jobspec/parse_service.go
Seth Hoenig 14c7cebdea connect: enable automatic expose paths for individual group service checks
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.
2020-03-31 17:15:50 -06:00

639 lines
15 KiB
Go

package jobspec
import (
"fmt"
multierror "github.com/hashicorp/go-multierror"
"github.com/hashicorp/hcl"
"github.com/hashicorp/hcl/hcl/ast"
"github.com/hashicorp/nomad/api"
"github.com/hashicorp/nomad/helper"
"github.com/mitchellh/mapstructure"
)
func parseGroupServices(g *api.TaskGroup, serviceObjs *ast.ObjectList) error {
g.Services = make([]*api.Service, len(serviceObjs.Items))
for idx, o := range serviceObjs.Items {
service, err := parseService(o)
if err != nil {
return multierror.Prefix(err, fmt.Sprintf("service (%d):", idx))
}
g.Services[idx] = service
}
return nil
}
func parseServices(serviceObjs *ast.ObjectList) ([]*api.Service, error) {
services := make([]*api.Service, len(serviceObjs.Items))
for idx, o := range serviceObjs.Items {
service, err := parseService(o)
if err != nil {
return nil, multierror.Prefix(err, fmt.Sprintf("service (%d):", idx))
}
services[idx] = service
}
return services, nil
}
func parseService(o *ast.ObjectItem) (*api.Service, error) {
// Check for invalid keys
valid := []string{
"name",
"tags",
"canary_tags",
"enable_tag_override",
"port",
"check",
"address_mode",
"check_restart",
"connect",
"meta",
"canary_meta",
}
if err := helper.CheckHCLKeys(o.Val, valid); err != nil {
return nil, err
}
var service api.Service
var m map[string]interface{}
if err := hcl.DecodeObject(&m, o.Val); err != nil {
return nil, err
}
delete(m, "check")
delete(m, "check_restart")
delete(m, "connect")
delete(m, "meta")
delete(m, "canary_meta")
if err := mapstructure.WeakDecode(m, &service); err != nil {
return nil, err
}
// Filter list
var listVal *ast.ObjectList
if ot, ok := o.Val.(*ast.ObjectType); ok {
listVal = ot.List
} else {
return nil, fmt.Errorf("'%s': should be an object", service.Name)
}
if co := listVal.Filter("check"); len(co.Items) > 0 {
if err := parseChecks(&service, co); err != nil {
return nil, multierror.Prefix(err, fmt.Sprintf("'%s',", service.Name))
}
}
// Filter check_restart
if cro := listVal.Filter("check_restart"); len(cro.Items) > 0 {
if len(cro.Items) > 1 {
return nil, fmt.Errorf("check_restart '%s': cannot have more than 1 check_restart", service.Name)
}
cr, err := parseCheckRestart(cro.Items[0])
if err != nil {
return nil, multierror.Prefix(err, fmt.Sprintf("'%s',", service.Name))
}
service.CheckRestart = cr
}
// Filter connect
if co := listVal.Filter("connect"); len(co.Items) > 0 {
if len(co.Items) > 1 {
return nil, fmt.Errorf("connect '%s': cannot have more than 1 connect stanza", service.Name)
}
c, err := parseConnect(co.Items[0])
if err != nil {
return nil, multierror.Prefix(err, fmt.Sprintf("'%s',", service.Name))
}
service.Connect = c
}
// Parse out meta fields. These are in HCL as a list so we need
// to iterate over them and merge them.
if metaO := listVal.Filter("meta"); len(metaO.Items) > 0 {
for _, o := range metaO.Elem().Items {
var m map[string]interface{}
if err := hcl.DecodeObject(&m, o.Val); err != nil {
return nil, err
}
if err := mapstructure.WeakDecode(m, &service.Meta); err != nil {
return nil, err
}
}
}
// Parse out canary_meta fields. These are in HCL as a list so we need
// to iterate over them and merge them.
if metaO := listVal.Filter("canary_meta"); len(metaO.Items) > 0 {
for _, o := range metaO.Elem().Items {
var m map[string]interface{}
if err := hcl.DecodeObject(&m, o.Val); err != nil {
return nil, err
}
if err := mapstructure.WeakDecode(m, &service.CanaryMeta); err != nil {
return nil, err
}
}
}
return &service, nil
}
func parseConnect(co *ast.ObjectItem) (*api.ConsulConnect, error) {
valid := []string{
"native",
"sidecar_service",
"sidecar_task",
}
if err := helper.CheckHCLKeys(co.Val, valid); err != nil {
return nil, multierror.Prefix(err, "connect ->")
}
var connect api.ConsulConnect
var m map[string]interface{}
if err := hcl.DecodeObject(&m, co.Val); err != nil {
return nil, err
}
delete(m, "sidecar_service")
delete(m, "sidecar_task")
if err := mapstructure.WeakDecode(m, &connect); err != nil {
return nil, err
}
var connectList *ast.ObjectList
if ot, ok := co.Val.(*ast.ObjectType); ok {
connectList = ot.List
} else {
return nil, fmt.Errorf("connect should be an object")
}
// Parse the sidecar_service
o := connectList.Filter("sidecar_service")
if len(o.Items) == 0 {
return &connect, nil
}
if len(o.Items) > 1 {
return nil, fmt.Errorf("only one 'sidecar_service' block allowed per task")
}
r, err := parseSidecarService(o.Items[0])
if err != nil {
return nil, fmt.Errorf("sidecar_service, %v", err)
}
connect.SidecarService = r
// Parse the sidecar_task
o = connectList.Filter("sidecar_task")
if len(o.Items) == 0 {
return &connect, nil
}
if len(o.Items) > 1 {
return nil, fmt.Errorf("only one 'sidecar_task' block allowed per task")
}
t, err := parseSidecarTask(o.Items[0])
if err != nil {
return nil, fmt.Errorf("sidecar_task, %v", err)
}
connect.SidecarTask = t
return &connect, nil
}
func parseSidecarService(o *ast.ObjectItem) (*api.ConsulSidecarService, error) {
valid := []string{
"port",
"proxy",
"tags",
}
if err := helper.CheckHCLKeys(o.Val, valid); err != nil {
return nil, multierror.Prefix(err, "sidecar_service ->")
}
var sidecar api.ConsulSidecarService
var m map[string]interface{}
if err := hcl.DecodeObject(&m, o.Val); err != nil {
return nil, err
}
delete(m, "proxy")
dec, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
DecodeHook: mapstructure.StringToTimeDurationHookFunc(),
WeaklyTypedInput: true,
Result: &sidecar,
})
if err != nil {
return nil, err
}
if err := dec.Decode(m); err != nil {
return nil, fmt.Errorf("sidecar_service: %v", err)
}
var proxyList *ast.ObjectList
if ot, ok := o.Val.(*ast.ObjectType); ok {
proxyList = ot.List
} else {
return nil, fmt.Errorf("sidecar_service: should be an object")
}
// Parse the proxy
po := proxyList.Filter("proxy")
if len(po.Items) == 0 {
return &sidecar, nil
}
if len(po.Items) > 1 {
return nil, fmt.Errorf("only one 'proxy' block allowed per task")
}
r, err := parseProxy(po.Items[0])
if err != nil {
return nil, fmt.Errorf("proxy, %v", err)
}
sidecar.Proxy = r
return &sidecar, nil
}
func parseSidecarTask(item *ast.ObjectItem) (*api.SidecarTask, error) {
// We need this later
var listVal *ast.ObjectList
if ot, ok := item.Val.(*ast.ObjectType); ok {
listVal = ot.List
} else {
return nil, fmt.Errorf("should be an object")
}
// Check for invalid keys
valid := []string{
"config",
"driver",
"env",
"kill_timeout",
"logs",
"meta",
"resources",
"shutdown_delay",
"user",
"kill_signal",
}
if err := helper.CheckHCLKeys(listVal, valid); err != nil {
return nil, err
}
task, err := parseTask(item)
if err != nil {
return nil, err
}
sidecarTask := &api.SidecarTask{
Name: task.Name,
Driver: task.Driver,
User: task.User,
Config: task.Config,
Env: task.Env,
Resources: task.Resources,
Meta: task.Meta,
KillTimeout: task.KillTimeout,
LogConfig: task.LogConfig,
KillSignal: task.KillSignal,
}
// Parse ShutdownDelay separately to get pointer
var m map[string]interface{}
if err := hcl.DecodeObject(&m, item.Val); err != nil {
return nil, err
}
m = map[string]interface{}{
"shutdown_delay": m["shutdown_delay"],
}
dec, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
DecodeHook: mapstructure.StringToTimeDurationHookFunc(),
WeaklyTypedInput: true,
Result: sidecarTask,
})
if err != nil {
return nil, err
}
if err := dec.Decode(m); err != nil {
return nil, err
}
return sidecarTask, nil
}
func parseProxy(o *ast.ObjectItem) (*api.ConsulProxy, error) {
valid := []string{
"local_service_address",
"local_service_port",
"upstreams",
"expose",
"config",
}
if err := helper.CheckHCLKeys(o.Val, valid); err != nil {
return nil, multierror.Prefix(err, "proxy ->")
}
var proxy api.ConsulProxy
var listVal *ast.ObjectList
if ot, ok := o.Val.(*ast.ObjectType); ok {
listVal = ot.List
} else {
return nil, fmt.Errorf("proxy: should be an object")
}
// Parse the proxy
uo := listVal.Filter("upstreams")
if len(uo.Items) > 0 {
proxy.Upstreams = make([]*api.ConsulUpstream, len(uo.Items))
for i := range uo.Items {
u, err := parseUpstream(uo.Items[i])
if err != nil {
return nil, err
}
proxy.Upstreams[i] = u
}
}
if eo := listVal.Filter("expose"); len(eo.Items) > 1 {
return nil, fmt.Errorf("only 1 expose object supported")
} else if len(eo.Items) == 1 {
if e, err := parseExpose(eo.Items[0]); err != nil {
return nil, err
} else {
proxy.ExposeConfig = e
}
}
// If we have config, then parse that
if o := listVal.Filter("config"); len(o.Items) > 1 {
return nil, fmt.Errorf("only 1 meta object supported")
} else if len(o.Items) == 1 {
var mSlice []map[string]interface{}
if err := hcl.DecodeObject(&mSlice, o.Items[0].Val); err != nil {
return nil, err
}
if len(mSlice) > 1 {
return nil, fmt.Errorf("only 1 meta object supported")
}
m := mSlice[0]
if err := mapstructure.WeakDecode(m, &proxy.Config); err != nil {
return nil, err
}
proxy.Config = flattenMapSlice(proxy.Config)
}
return &proxy, nil
}
func parseExpose(eo *ast.ObjectItem) (*api.ConsulExposeConfig, error) {
valid := []string{
"path", // an array of path blocks
}
if err := helper.CheckHCLKeys(eo.Val, valid); err != nil {
return nil, multierror.Prefix(err, "expose ->")
}
var expose api.ConsulExposeConfig
var listVal *ast.ObjectList
if eoType, ok := eo.Val.(*ast.ObjectType); ok {
listVal = eoType.List
} else {
return nil, fmt.Errorf("expose: should be an object")
}
// Parse the expose block
po := listVal.Filter("path") // array
if len(po.Items) > 0 {
expose.Path = make([]*api.ConsulExposePath, len(po.Items))
for i := range po.Items {
p, err := parseExposePath(po.Items[i])
if err != nil {
return nil, err
}
expose.Path[i] = p
}
}
return &expose, nil
}
func parseExposePath(epo *ast.ObjectItem) (*api.ConsulExposePath, error) {
valid := []string{
"path",
"protocol",
"local_path_port",
"listener_port",
}
if err := helper.CheckHCLKeys(epo.Val, valid); err != nil {
return nil, multierror.Prefix(err, "path ->")
}
var path api.ConsulExposePath
var m map[string]interface{}
if err := hcl.DecodeObject(&m, epo.Val); err != nil {
return nil, err
}
dec, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
Result: &path,
})
if err != nil {
return nil, err
}
if err := dec.Decode(m); err != nil {
return nil, err
}
return &path, nil
}
func parseUpstream(uo *ast.ObjectItem) (*api.ConsulUpstream, error) {
valid := []string{
"destination_name",
"local_bind_port",
}
if err := helper.CheckHCLKeys(uo.Val, valid); err != nil {
return nil, multierror.Prefix(err, "upstream ->")
}
var upstream api.ConsulUpstream
var m map[string]interface{}
if err := hcl.DecodeObject(&m, uo.Val); err != nil {
return nil, err
}
dec, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
DecodeHook: mapstructure.StringToTimeDurationHookFunc(),
WeaklyTypedInput: true,
Result: &upstream,
})
if err != nil {
return nil, err
}
if err := dec.Decode(m); err != nil {
return nil, err
}
return &upstream, nil
}
func parseChecks(service *api.Service, checkObjs *ast.ObjectList) error {
service.Checks = make([]api.ServiceCheck, len(checkObjs.Items))
for idx, co := range checkObjs.Items {
// Check for invalid keys
valid := []string{
"name",
"type",
"interval",
"timeout",
"path",
"protocol",
"port",
"expose",
"command",
"args",
"initial_status",
"tls_skip_verify",
"header",
"method",
"check_restart",
"address_mode",
"grpc_service",
"grpc_use_tls",
"task",
}
if err := helper.CheckHCLKeys(co.Val, valid); err != nil {
return multierror.Prefix(err, "check ->")
}
var check api.ServiceCheck
var cm map[string]interface{}
if err := hcl.DecodeObject(&cm, co.Val); err != nil {
return err
}
// HCL allows repeating stanzas so merge 'header' into a single
// map[string][]string.
if headerI, ok := cm["header"]; ok {
headerRaw, ok := headerI.([]map[string]interface{})
if !ok {
return fmt.Errorf("check -> header -> expected a []map[string][]string but found %T", headerI)
}
m := map[string][]string{}
for _, rawm := range headerRaw {
for k, vI := range rawm {
vs, ok := vI.([]interface{})
if !ok {
return fmt.Errorf("check -> header -> %q expected a []string but found %T", k, vI)
}
for _, vI := range vs {
v, ok := vI.(string)
if !ok {
return fmt.Errorf("check -> header -> %q expected a string but found %T", k, vI)
}
m[k] = append(m[k], v)
}
}
}
check.Header = m
// Remove "header" as it has been parsed
delete(cm, "header")
}
delete(cm, "check_restart")
dec, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
DecodeHook: mapstructure.StringToTimeDurationHookFunc(),
WeaklyTypedInput: true,
Result: &check,
})
if err != nil {
return err
}
if err := dec.Decode(cm); err != nil {
return err
}
// Filter check_restart
var checkRestartList *ast.ObjectList
if ot, ok := co.Val.(*ast.ObjectType); ok {
checkRestartList = ot.List
} else {
return fmt.Errorf("check_restart '%s': should be an object", check.Name)
}
if cro := checkRestartList.Filter("check_restart"); len(cro.Items) > 0 {
if len(cro.Items) > 1 {
return fmt.Errorf("check_restart '%s': cannot have more than 1 check_restart", check.Name)
}
cr, err := parseCheckRestart(cro.Items[0])
if err != nil {
return multierror.Prefix(err, fmt.Sprintf("check: '%s',", check.Name))
}
check.CheckRestart = cr
}
service.Checks[idx] = check
}
return nil
}
func parseCheckRestart(cro *ast.ObjectItem) (*api.CheckRestart, error) {
valid := []string{
"limit",
"grace",
"ignore_warnings",
}
if err := helper.CheckHCLKeys(cro.Val, valid); err != nil {
return nil, multierror.Prefix(err, "check_restart ->")
}
var checkRestart api.CheckRestart
var crm map[string]interface{}
if err := hcl.DecodeObject(&crm, cro.Val); err != nil {
return nil, err
}
dec, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
DecodeHook: mapstructure.StringToTimeDurationHookFunc(),
WeaklyTypedInput: true,
Result: &checkRestart,
})
if err != nil {
return nil, err
}
if err := dec.Decode(crm); err != nil {
return nil, err
}
return &checkRestart, nil
}