open-consul/agent/catalog_endpoint.go
Preetha 8fbe3dfceb
Adds discovery_max_stale (#4004)
Adds a new option to allow service discovery endpoints to return stale results if configured at the agent level.
2018-03-30 10:14:44 -05:00

278 lines
9.8 KiB
Go

package agent
import (
"fmt"
"net/http"
"strings"
metrics "github.com/armon/go-metrics"
"github.com/hashicorp/consul/agent/structs"
)
var durations = NewDurationFixer("interval", "timeout", "deregistercriticalserviceafter")
func (s *HTTPServer) CatalogRegister(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
metrics.IncrCounterWithLabels([]string{"client", "api", "catalog_register"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
var args structs.RegisterRequest
if err := decodeBody(req, &args, durations.FixupDurations); err != nil {
resp.WriteHeader(http.StatusBadRequest)
fmt.Fprintf(resp, "Request decode failed: %v", err)
return nil, nil
}
// Setup the default DC if not provided
if args.Datacenter == "" {
args.Datacenter = s.agent.config.Datacenter
}
s.parseToken(req, &args.Token)
// Forward to the servers
var out struct{}
if err := s.agent.RPC("Catalog.Register", &args, &out); err != nil {
metrics.IncrCounterWithLabels([]string{"client", "rpc", "error", "catalog_register"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return nil, err
}
metrics.IncrCounterWithLabels([]string{"client", "api", "success", "catalog_register"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return true, nil
}
func (s *HTTPServer) CatalogDeregister(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
metrics.IncrCounterWithLabels([]string{"client", "api", "catalog_deregister"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
var args structs.DeregisterRequest
if err := decodeBody(req, &args, nil); err != nil {
resp.WriteHeader(http.StatusBadRequest)
fmt.Fprintf(resp, "Request decode failed: %v", err)
return nil, nil
}
// Setup the default DC if not provided
if args.Datacenter == "" {
args.Datacenter = s.agent.config.Datacenter
}
s.parseToken(req, &args.Token)
// Forward to the servers
var out struct{}
if err := s.agent.RPC("Catalog.Deregister", &args, &out); err != nil {
metrics.IncrCounterWithLabels([]string{"client", "rpc", "error", "catalog_deregister"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return nil, err
}
metrics.IncrCounterWithLabels([]string{"client", "api", "success", "catalog_deregister"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return true, nil
}
func (s *HTTPServer) CatalogDatacenters(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
metrics.IncrCounterWithLabels([]string{"client", "api", "catalog_datacenters"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
var out []string
if err := s.agent.RPC("Catalog.ListDatacenters", struct{}{}, &out); err != nil {
metrics.IncrCounterWithLabels([]string{"client", "rpc", "error", "catalog_datacenters"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return nil, err
}
metrics.IncrCounterWithLabels([]string{"client", "api", "success", "catalog_datacenters"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return out, nil
}
func (s *HTTPServer) CatalogNodes(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
metrics.IncrCounterWithLabels([]string{"client", "api", "catalog_nodes"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
// Setup the request
args := structs.DCSpecificRequest{}
s.parseSource(req, &args.Source)
args.NodeMetaFilters = s.parseMetaFilter(req)
if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
metrics.IncrCounterWithLabels([]string{"client", "rpc", "error", "catalog_nodes"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return nil, nil
}
var out structs.IndexedNodes
defer setMeta(resp, &out.QueryMeta)
RETRY_ONCE:
if err := s.agent.RPC("Catalog.ListNodes", &args, &out); err != nil {
return nil, err
}
if args.QueryOptions.AllowStale && args.MaxStaleDuration > 0 && args.MaxStaleDuration < out.LastContact {
args.AllowStale = false
args.MaxStaleDuration = 0
goto RETRY_ONCE
}
out.ConsistencyLevel = args.QueryOptions.ConsistencyLevel()
s.agent.TranslateAddresses(args.Datacenter, out.Nodes)
// Use empty list instead of nil
if out.Nodes == nil {
out.Nodes = make(structs.Nodes, 0)
}
metrics.IncrCounterWithLabels([]string{"client", "api", "success", "catalog_nodes"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return out.Nodes, nil
}
func (s *HTTPServer) CatalogServices(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
metrics.IncrCounterWithLabels([]string{"client", "api", "catalog_services"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
// Set default DC
args := structs.DCSpecificRequest{}
args.NodeMetaFilters = s.parseMetaFilter(req)
if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
return nil, nil
}
var out structs.IndexedServices
defer setMeta(resp, &out.QueryMeta)
RETRY_ONCE:
if err := s.agent.RPC("Catalog.ListServices", &args, &out); err != nil {
metrics.IncrCounterWithLabels([]string{"client", "rpc", "error", "catalog_services"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return nil, err
}
if args.QueryOptions.AllowStale && args.MaxStaleDuration > 0 && args.MaxStaleDuration < out.LastContact {
args.AllowStale = false
args.MaxStaleDuration = 0
goto RETRY_ONCE
}
out.ConsistencyLevel = args.QueryOptions.ConsistencyLevel()
// Use empty map instead of nil
if out.Services == nil {
out.Services = make(structs.Services, 0)
}
metrics.IncrCounterWithLabels([]string{"client", "api", "success", "catalog_services"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return out.Services, nil
}
func (s *HTTPServer) CatalogServiceNodes(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
metrics.IncrCounterWithLabels([]string{"client", "api", "catalog_service_nodes"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
// Set default DC
args := structs.ServiceSpecificRequest{}
s.parseSource(req, &args.Source)
args.NodeMetaFilters = s.parseMetaFilter(req)
if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
return nil, nil
}
// Check for a tag
params := req.URL.Query()
if _, ok := params["tag"]; ok {
args.ServiceTag = params.Get("tag")
args.TagFilter = true
}
// Pull out the service name
args.ServiceName = strings.TrimPrefix(req.URL.Path, "/v1/catalog/service/")
if args.ServiceName == "" {
resp.WriteHeader(http.StatusBadRequest)
fmt.Fprint(resp, "Missing service name")
return nil, nil
}
// Make the RPC request
var out structs.IndexedServiceNodes
defer setMeta(resp, &out.QueryMeta)
RETRY_ONCE:
if err := s.agent.RPC("Catalog.ServiceNodes", &args, &out); err != nil {
metrics.IncrCounterWithLabels([]string{"client", "rpc", "error", "catalog_service_nodes"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return nil, err
}
if args.QueryOptions.AllowStale && args.MaxStaleDuration > 0 && args.MaxStaleDuration < out.LastContact {
args.AllowStale = false
args.MaxStaleDuration = 0
goto RETRY_ONCE
}
out.ConsistencyLevel = args.QueryOptions.ConsistencyLevel()
s.agent.TranslateAddresses(args.Datacenter, out.ServiceNodes)
// Use empty list instead of nil
if out.ServiceNodes == nil {
out.ServiceNodes = make(structs.ServiceNodes, 0)
}
for i, s := range out.ServiceNodes {
if s.ServiceTags == nil {
clone := *s
clone.ServiceTags = make([]string, 0)
out.ServiceNodes[i] = &clone
}
}
metrics.IncrCounterWithLabels([]string{"client", "api", "success", "catalog_service_nodes"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return out.ServiceNodes, nil
}
func (s *HTTPServer) CatalogNodeServices(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
metrics.IncrCounterWithLabels([]string{"client", "api", "catalog_node_services"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
// Set default Datacenter
args := structs.NodeSpecificRequest{}
if done := s.parse(resp, req, &args.Datacenter, &args.QueryOptions); done {
return nil, nil
}
// Pull out the node name
args.Node = strings.TrimPrefix(req.URL.Path, "/v1/catalog/node/")
if args.Node == "" {
resp.WriteHeader(http.StatusBadRequest)
fmt.Fprint(resp, "Missing node name")
return nil, nil
}
// Make the RPC request
var out structs.IndexedNodeServices
defer setMeta(resp, &out.QueryMeta)
RETRY_ONCE:
if err := s.agent.RPC("Catalog.NodeServices", &args, &out); err != nil {
metrics.IncrCounterWithLabels([]string{"client", "rpc", "error", "catalog_node_services"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return nil, err
}
if args.QueryOptions.AllowStale && args.MaxStaleDuration > 0 && args.MaxStaleDuration < out.LastContact {
args.AllowStale = false
args.MaxStaleDuration = 0
goto RETRY_ONCE
}
out.ConsistencyLevel = args.QueryOptions.ConsistencyLevel()
if out.NodeServices != nil && out.NodeServices.Node != nil {
s.agent.TranslateAddresses(args.Datacenter, out.NodeServices.Node)
}
// TODO: The NodeServices object in IndexedNodeServices is a pointer to
// something that's created for each request by the state store way down
// in https://github.com/hashicorp/consul/blob/v1.0.4/agent/consul/state/catalog.go#L953-L963.
// Since this isn't a pointer to a real state store object, it's safe to
// modify out.NodeServices.Services in the loop below without making a
// copy here. Same for the Tags in each service entry, since that was
// created by .ToNodeService() which made a copy. This is safe as-is but
// this whole business is tricky and subtle. See #3867 for more context.
// Use empty list instead of nil
if out.NodeServices != nil {
for _, s := range out.NodeServices.Services {
if s.Tags == nil {
s.Tags = make([]string, 0)
}
}
}
metrics.IncrCounterWithLabels([]string{"client", "api", "success", "catalog_node_services"}, 1,
[]metrics.Label{{Name: "node", Value: s.nodeName()}})
return out.NodeServices, nil
}