add cert info and renewal api

internal/api/v1/certapi/cert_info.go

@@ -0,0 +1,41 @@
+package certapi
+
+import (
+	"encoding/json"
+	"net/http"
+
+	config "github.com/yusing/go-proxy/internal/config/types"
+)
+
+type CertInfo struct {
+	Subject        string   `json:"subject"`
+	Issuer         string   `json:"issuer"`
+	NotBefore      int64    `json:"not_before"`
+	NotAfter       int64    `json:"not_after"`
+	DNSNames       []string `json:"dns_names"`
+	EmailAddresses []string `json:"email_addresses"`
+}
+
+func GetCertInfo(w http.ResponseWriter, r *http.Request) {
+	autocert := config.GetInstance().AutoCertProvider()
+	if autocert == nil {
+		http.Error(w, "autocert is not enabled", http.StatusNotFound)
+		return
+	}
+
+	cert, err := autocert.GetCert(nil)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	certInfo := CertInfo{
+		Subject:        cert.Leaf.Subject.CommonName,
+		Issuer:         cert.Leaf.Issuer.CommonName,
+		NotBefore:      cert.Leaf.NotBefore.Unix(),
+		NotAfter:       cert.Leaf.NotAfter.Unix(),
+		DNSNames:       cert.Leaf.DNSNames,
+		EmailAddresses: cert.Leaf.EmailAddresses,
+	}
+	json.NewEncoder(w).Encode(&certInfo)
+}