Advertise signalling abilities

client/driver/docker.go

@@ -266,6 +266,12 @@ func (d *DockerDriver) Validate(config map[string]interface{}) error {
 	return nil
 }
 
+func (d *DockerDriver) Abilities() DriverAbilities {
+	return DriverAbilities{
+		SendSignals: true,
+	}
+}
+
 // dockerClients creates two *docker.Client, one for long running operations and
 // the other for shorter operations. In test / dev mode we can use ENV vars to
 // connect to the docker daemon. In production mode we will read docker.endpoint

client/driver/driver.go

@@ -59,6 +59,15 @@ type Driver interface {
 
 	// Drivers must validate their configuration
 	Validate(map[string]interface{}) error
+
+	// Abilities returns the abilities of the driver
+	Abilities() DriverAbilities
+}
+
+// DriverAbilities marks the abilities the driver has.
+type DriverAbilities struct {
+	// SendSignals marks the driver as being able to send signals
+	SendSignals bool
 }
 
 // DriverContext is a means to inject dependencies such as loggers, configs, and

client/driver/exec.go

@@ -82,6 +82,12 @@ func (d *ExecDriver) Validate(config map[string]interface{}) error {
 	return nil
 }
 
+func (d *ExecDriver) Abilities() DriverAbilities {
+	return DriverAbilities{
+		SendSignals: true,
+	}
+}
+
 func (d *ExecDriver) Periodic() (bool, time.Duration) {
 	return true, 15 * time.Second
 }

client/driver/java.go

@@ -94,6 +94,12 @@ func (d *JavaDriver) Validate(config map[string]interface{}) error {
 	return nil
 }
 
+func (d *JavaDriver) Abilities() DriverAbilities {
+	return DriverAbilities{
+		SendSignals: true,
+	}
+}
+
 func (d *JavaDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, error) {
 	// Get the current status so that we can log any debug messages only if the
 	// state changes

client/driver/mock_driver.go

@@ -62,6 +62,12 @@ func NewMockDriver(ctx *DriverContext) Driver {
 	return &MockDriver{DriverContext: *ctx}
 }
 
+func (d *MockDriver) Abilities() DriverAbilities {
+	return DriverAbilities{
+		SendSignals: false,
+	}
+}
+
 // Start starts the mock driver
 func (m *MockDriver) Start(ctx *ExecContext, task *structs.Task) (DriverHandle, error) {
 	var driverConfig MockDriverConfig

client/driver/qemu.go

@@ -97,6 +97,12 @@ func (d *QemuDriver) Validate(config map[string]interface{}) error {
 	return nil
 }
 
+func (d *QemuDriver) Abilities() DriverAbilities {
+	return DriverAbilities{
+		SendSignals: false,
+	}
+}
+
 func (d *QemuDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, error) {
 	// Get the current status so that we can log any debug messages only if the
 	// state changes

client/driver/raw_exec.go

@@ -81,6 +81,12 @@ func (d *RawExecDriver) Validate(config map[string]interface{}) error {
 	return nil
 }
 
+func (d *RawExecDriver) Abilities() DriverAbilities {
+	return DriverAbilities{
+		SendSignals: true,
+	}
+}
+
 func (d *RawExecDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, error) {
 	// Get the current status so that we can log any debug messages only if the
 	// state changes

client/driver/rkt.go

@@ -128,6 +128,12 @@ func (d *RktDriver) Validate(config map[string]interface{}) error {
 	return nil
 }
 
+func (d *RktDriver) Abilities() DriverAbilities {
+	return DriverAbilities{
+		SendSignals: false,
+	}
+}
+
 func (d *RktDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, error) {
 	// Get the current status so that we can log any debug messages only if the
 	// state changes

client/fingerprint/fingerprint.go

@@ -25,6 +25,7 @@ func init() {
 	builtinFingerprintMap["memory"] = NewMemoryFingerprint
 	builtinFingerprintMap["network"] = NewNetworkFingerprint
 	builtinFingerprintMap["nomad"] = NewNomadFingerprint
+	builtinFingerprintMap["signal"] = NewSignalFingerprint
 	builtinFingerprintMap["storage"] = NewStorageFingerprint
 	builtinFingerprintMap["vault"] = NewVaultFingerprint
 

client/fingerprint/signal.go

@@ -0,0 +1,33 @@
+package fingerprint
+
+import (
+	"log"
+	"strings"
+
+	"github.com/hashicorp/consul-template/signals"
+	"github.com/hashicorp/nomad/client/config"
+	"github.com/hashicorp/nomad/nomad/structs"
+)
+
+// SignalFingerprint is used to fingerprint the available signals
+type SignalFingerprint struct {
+	StaticFingerprinter
+	logger *log.Logger
+}
+
+// NewSignalFingerprint is used to create a Signal fingerprint
+func NewSignalFingerprint(logger *log.Logger) Fingerprint {
+	f := &SignalFingerprint{logger: logger}
+	return f
+}
+
+func (f *SignalFingerprint) Fingerprint(cfg *config.Config, node *structs.Node) (bool, error) {
+	// Build the list of available signals
+	sigs := make([]string, 0, len(signals.SignalLookup))
+	for signal := range signals.SignalLookup {
+		sigs = append(sigs, signal)
+	}
+
+	node.Attributes["os.signals"] = strings.Join(sigs, ",")
+	return true, nil
+}

client/fingerprint/signal_test.go

@@ -0,0 +1,17 @@
+package fingerprint
+
+import (
+	"testing"
+
+	"github.com/hashicorp/nomad/nomad/structs"
+)
+
+func TestSignalFingerprint(t *testing.T) {
+	fp := NewSignalFingerprint(testLogger())
+	node := &structs.Node{
+		Attributes: make(map[string]string),
+	}
+
+	assertFingerprintOK(t, fp, node)
+	assertNodeAttributeContains(t, node, "os.signals")
+}