open-nomad/client/fingerprint/fingerprint.go

88 lines
2.9 KiB
Go

package fingerprint
import (
"fmt"
"log"
"sort"
"time"
"github.com/hashicorp/nomad/client/config"
"github.com/hashicorp/nomad/nomad/structs"
)
// EmptyDuration is to be used by fingerprinters that are not periodic.
const (
EmptyDuration = time.Duration(0)
)
func init() {
builtinFingerprintMap["arch"] = NewArchFingerprint
builtinFingerprintMap["cpu"] = NewCPUFingerprint
builtinFingerprintMap["env_aws"] = NewEnvAWSFingerprint
builtinFingerprintMap["env_gce"] = NewEnvGCEFingerprint
builtinFingerprintMap["host"] = NewHostFingerprint
builtinFingerprintMap["memory"] = NewMemoryFingerprint
builtinFingerprintMap["network"] = NewNetworkFingerprint
builtinFingerprintMap["nomad"] = NewNomadFingerprint
builtinFingerprintMap["storage"] = NewStorageFingerprint
// Initialize the list of available fingerprinters per platform. Each
// platform defines its own list of available fingerprinters.
initPlatformFingerprints(builtinFingerprintMap)
}
// builtinFingerprintMap contains the built in registered fingerprints which are
// available for a given platform.
var builtinFingerprintMap = make(map[string]Factory, 16)
// BuiltinFingerprints is a slice containing the key names of all registered
// fingerprints available, to provided an ordered iteration
func BuiltinFingerprints() []string {
fingerprints := make([]string, 0, len(builtinFingerprintMap))
for k := range builtinFingerprintMap {
fingerprints = append(fingerprints, k)
}
sort.Strings(fingerprints)
return fingerprints
}
// NewFingerprint is used to instantiate and return a new fingerprint
// given the name and a logger
func NewFingerprint(name string, logger *log.Logger) (Fingerprint, error) {
// Lookup the factory function
factory, ok := builtinFingerprintMap[name]
if !ok {
return nil, fmt.Errorf("unknown fingerprint '%s'", name)
}
// Instantiate the fingerprint
f := factory(logger)
return f, nil
}
// Factory is used to instantiate a new Fingerprint
type Factory func(*log.Logger) Fingerprint
// Fingerprint is used for doing "fingerprinting" of the
// host to automatically determine attributes, resources,
// and metadata about it. Each of these is a heuristic, and
// many of them can be applied on a particular host.
type Fingerprint interface {
// Fingerprint is used to update properties of the Node,
// and returns if the fingerprint was applicable and a potential error.
Fingerprint(*config.Config, *structs.Node) (bool, error)
// Periodic is a mechanism for the fingerprinter to indicate that it should
// be run periodically. The return value is a boolean indicating if it
// should be periodic, and if true, a duration.
Periodic() (bool, time.Duration)
}
// StaticFingerprinter can be embedded in a struct that has a Fingerprint method
// to make it non-periodic.
type StaticFingerprinter struct{}
func (s *StaticFingerprinter) Periodic() (bool, time.Duration) {
return false, EmptyDuration
}