Add ID function to LogInfo to return log ID

logs.go

@@ -11,6 +11,7 @@ package certspotter
 
 import (
 	"crypto"
+	"crypto/sha256"
 	"crypto/x509"
 	"encoding/base64"
 )
@@ -37,6 +38,11 @@ func (info *LogInfo) ParsedPublicKey() (crypto.PublicKey, error) {
 	}
 }
 
+func (info *LogInfo) ID() []byte {
+	sum := sha256.Sum256(info.Key)
+	return sum[:]
+}
+
 var DefaultLogs = []LogInfo{
 	{
 		// a4b90990b418581487bb13a2cc67700a3c359804f91bdfb8e377cd0ec80ddc10