Move acmeClient creation into own file & struct (#179)

get rid of gobal vars and make make functions with less args :)

tldr: collect funcs and create a own ACME client to manage that stuff

Reviewed-on: https://codeberg.org/Codeberg/pages-server/pulls/179

server/certificates/cached_challengers.go

@@ -0,0 +1,41 @@
+package certificates
+
+import (
+	"time"
+
+	"github.com/go-acme/lego/v4/challenge"
+
+	"codeberg.org/codeberg/pages/server/cache"
+)
+
+type AcmeTLSChallengeProvider struct {
+	challengeCache cache.SetGetKey
+}
+
+// make sure AcmeTLSChallengeProvider match Provider interface
+var _ challenge.Provider = AcmeTLSChallengeProvider{}
+
+func (a AcmeTLSChallengeProvider) Present(domain, _, keyAuth string) error {
+	return a.challengeCache.Set(domain, keyAuth, 1*time.Hour)
+}
+
+func (a AcmeTLSChallengeProvider) CleanUp(domain, _, _ string) error {
+	a.challengeCache.Remove(domain)
+	return nil
+}
+
+type AcmeHTTPChallengeProvider struct {
+	challengeCache cache.SetGetKey
+}
+
+// make sure AcmeHTTPChallengeProvider match Provider interface
+var _ challenge.Provider = AcmeHTTPChallengeProvider{}
+
+func (a AcmeHTTPChallengeProvider) Present(domain, token, keyAuth string) error {
+	return a.challengeCache.Set(domain+"/"+token, keyAuth, 1*time.Hour)
+}
+
+func (a AcmeHTTPChallengeProvider) CleanUp(domain, token, _ string) error {
+	a.challengeCache.Remove(domain + "/" + token)
+	return nil
+}