Auto-create UDP service database

All other services operate like this, so make UDP service consistent.

cmd/influxd/run/server.go

@@ -292,6 +292,7 @@ func (s *Server) appendUDPService(c udp.Config) {
 	}
 	srv := udp.NewService(c)
 	srv.PointsWriter = s.PointsWriter
+	srv.MetaStore = s.MetaStore
 	s.Services = append(s.Services, srv)
 }
 

etc/config.sample.toml

@@ -235,7 +235,7 @@ reporting-disabled = false
 [[udp]]
   enabled = false
   # bind-address = ""
-  # database = ""
+  # database = "udp"
   # retention-policy = ""
 
   # These next lines control how batching works. You should have this enabled

services/udp/config.go

@@ -7,6 +7,9 @@ import (
 )
 
 const (
+	// DefaultDatabase is the default database for UDP traffic.
+	DefaultDatabase = "udp"
+
 	// DefaultBatchSize is the default UDP batch size.
 	DefaultBatchSize = 1000
 
@@ -32,6 +35,9 @@ type Config struct {
 // default values set.
 func (c *Config) WithDefaults() *Config {
 	d := *c
+	if d.Database == "" {
+		d.Database = DefaultDatabase
+	}
 	if d.BatchSize == 0 {
 		d.BatchSize = DefaultBatchSize
 	}

services/udp/service.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/influxdb/influxdb"
 	"github.com/influxdb/influxdb/cluster"
+	"github.com/influxdb/influxdb/meta"
 	"github.com/influxdb/influxdb/models"
 	"github.com/influxdb/influxdb/tsdb"
 )
@@ -49,6 +50,10 @@ type Service struct {
 		WritePoints(p *cluster.WritePointsRequest) error
 	}
 
+	MetaStore interface {
+		CreateDatabaseIfNotExists(name string) (*meta.DatabaseInfo, error)
+	}
+
 	Logger  *log.Logger
 	statMap *expvar.Map
 }
@@ -77,6 +82,10 @@ func (s *Service) Open() (err error) {
 		return errors.New("database has to be specified in config")
 	}
 
+	if _, err := s.MetaStore.CreateDatabaseIfNotExists(s.config.Database); err != nil {
+		return errors.New("Failed to ensure target database exists")
+	}
+
 	s.addr, err = net.ResolveUDPAddr("udp", s.config.BindAddress)
 	if err != nil {
 		s.Logger.Printf("Failed to resolve UDP address %s: %s", s.config.BindAddress, err)