traefik/provider/label/label.go
2018-10-17 16:24:04 +02:00

212 lines
6.3 KiB
Go

package label
import (
"fmt"
"net/http"
"regexp"
"strconv"
"strings"
"github.com/containous/traefik/log"
)
const (
mapEntrySeparator = "||"
mapValueSeparator = ":"
)
// Default values
const (
DefaultWeight = 1
DefaultProtocol = "http"
DefaultPassHostHeader = true
DefaultPassTLSCert = false
DefaultFrontendPriority = 0
DefaultCircuitBreakerExpression = "NetworkErrorRatio() > 1"
DefaultBackendLoadBalancerMethod = "wrr"
DefaultBackendMaxconnExtractorFunc = "request.host"
DefaultBackendLoadbalancerStickinessCookieName = ""
DefaultBackendHealthCheckPort = 0
)
var (
// RegexpFrontendErrorPage used to extract error pages from label
RegexpFrontendErrorPage = regexp.MustCompile(`^traefik\.frontend\.errors\.(?P<name>[^ .]+)\.(?P<field>[^ .]+)$`)
// RegexpFrontendRateLimit used to extract rate limits from label
RegexpFrontendRateLimit = regexp.MustCompile(`^traefik\.frontend\.rateLimit\.rateSet\.(?P<name>[^ .]+)\.(?P<field>[^ .]+)$`)
)
// GetStringValue get string value associated to a label
func GetStringValue(labels map[string]string, labelName string, defaultValue string) string {
if value, ok := labels[labelName]; ok && len(value) > 0 {
return value
}
return defaultValue
}
// GetBoolValue get bool value associated to a label
func GetBoolValue(labels map[string]string, labelName string, defaultValue bool) bool {
rawValue, ok := labels[labelName]
if ok {
v, err := strconv.ParseBool(rawValue)
if err == nil {
return v
}
log.Errorf("Unable to parse %q: %q, falling back to %v. %v", labelName, rawValue, defaultValue, err)
}
return defaultValue
}
// GetIntValue get int value associated to a label
func GetIntValue(labels map[string]string, labelName string, defaultValue int) int {
if rawValue, ok := labels[labelName]; ok {
value, err := strconv.Atoi(rawValue)
if err == nil {
return value
}
log.Errorf("Unable to parse %q: %q, falling back to %v. %v", labelName, rawValue, defaultValue, err)
}
return defaultValue
}
// GetInt64Value get int64 value associated to a label
func GetInt64Value(labels map[string]string, labelName string, defaultValue int64) int64 {
if rawValue, ok := labels[labelName]; ok {
value, err := strconv.ParseInt(rawValue, 10, 64)
if err == nil {
return value
}
log.Errorf("Unable to parse %q: %q, falling back to %v. %v", labelName, rawValue, defaultValue, err)
}
return defaultValue
}
// GetSliceStringValue get a slice of string associated to a label
func GetSliceStringValue(labels map[string]string, labelName string) []string {
var value []string
if values, ok := labels[labelName]; ok {
value = SplitAndTrimString(values, ",")
if len(value) == 0 {
log.Debugf("Could not load %q.", labelName)
}
}
return value
}
// ParseMapValue get Map value for a label value
func ParseMapValue(labelName, values string) map[string]string {
mapValue := make(map[string]string)
for _, parts := range strings.Split(values, mapEntrySeparator) {
pair := strings.SplitN(parts, mapValueSeparator, 2)
if len(pair) != 2 {
log.Warnf("Could not load %q: %q, skipping...", labelName, parts)
} else {
mapValue[http.CanonicalHeaderKey(strings.TrimSpace(pair[0]))] = strings.TrimSpace(pair[1])
}
}
if len(mapValue) == 0 {
log.Errorf("Could not load %q, skipping...", labelName)
return nil
}
return mapValue
}
// GetMapValue get Map value associated to a label
func GetMapValue(labels map[string]string, labelName string) map[string]string {
if values, ok := labels[labelName]; ok {
if len(values) == 0 {
log.Errorf("Missing value for %q, skipping...", labelName)
return nil
}
return ParseMapValue(labelName, values)
}
return nil
}
// GetStringMultipleStrict get multiple string values associated to several labels
// Fail if one label is missing
func GetStringMultipleStrict(labels map[string]string, labelNames ...string) (map[string]string, error) {
foundLabels := map[string]string{}
for _, name := range labelNames {
value := GetStringValue(labels, name, "")
// Error out only if one of them is not defined.
if len(value) == 0 {
return nil, fmt.Errorf("label not found: %s", name)
}
foundLabels[name] = value
}
return foundLabels, nil
}
// Has Check if a value is associated to a label
func Has(labels map[string]string, labelName string) bool {
value, ok := labels[labelName]
return ok && len(value) > 0
}
// HasPrefix Check if a value is associated to a less one label with a prefix
func HasPrefix(labels map[string]string, prefix string) bool {
for name, value := range labels {
if strings.HasPrefix(name, prefix) && len(value) > 0 {
return true
}
}
return false
}
// IsEnabled Check if a container is enabled in Traefik
func IsEnabled(labels map[string]string, exposedByDefault bool) bool {
return GetBoolValue(labels, TraefikEnable, exposedByDefault)
}
// SplitAndTrimString splits separatedString at the separator character and trims each
// piece, filtering out empty pieces. Returns the list of pieces or nil if the input
// did not contain a non-empty piece.
func SplitAndTrimString(base string, sep string) []string {
var trimmedStrings []string
for _, s := range strings.Split(base, sep) {
s = strings.TrimSpace(s)
if len(s) > 0 {
trimmedStrings = append(trimmedStrings, s)
}
}
return trimmedStrings
}
// GetFuncString a func related to GetStringValue
func GetFuncString(labelName string, defaultValue string) func(map[string]string) string {
return func(labels map[string]string) string {
return GetStringValue(labels, labelName, defaultValue)
}
}
// GetFuncInt a func related to GetIntValue
func GetFuncInt(labelName string, defaultValue int) func(map[string]string) int {
return func(labels map[string]string) int {
return GetIntValue(labels, labelName, defaultValue)
}
}
// GetFuncBool a func related to GetBoolValue
func GetFuncBool(labelName string, defaultValue bool) func(map[string]string) bool {
return func(labels map[string]string) bool {
return GetBoolValue(labels, labelName, defaultValue)
}
}
// GetFuncSliceString a func related to GetSliceStringValue
func GetFuncSliceString(labelName string) func(map[string]string) []string {
return func(labels map[string]string) []string {
return GetSliceStringValue(labels, labelName)
}
}