httpcaddyfile: Support repeated use of cert_issuer global option

This changes the signature of UnmarshalGlobalFunc but this is probably OK since it's only used by this repo as far as we know.

We need this change in order to "remember" the previous value in case a global option appears more than once, which is now a possibility with the cert_issuer option since Caddy now supports multiple issuers in the order defined by the user.

Bonus: the issuer subdirective of tls now supports one-liner for "acme" when all you need to set is the directory:

issuer acme <dir>

1 files changed, 5 insertions, 5 deletions

diff --git a/caddyconfig/httpcaddyfile/tlsapp.go b/caddyconfig/httpcaddyfile/tlsapp.go
index a66146da9..25b800a54 100644
--- a/caddyconfig/httpcaddyfile/tlsapp.go
+++ b/caddyconfig/httpcaddyfile/tlsapp.go
@@ -414,11 +414,11 @@ func fillInGlobalACMEDefaults(issuer certmagic.Issuer, options map[string]interf
 // returned if there are no default/global options. However, if always is
 // true, a non-nil value will always be returned (unless there is an error).
 func newBaseAutomationPolicy(options map[string]interface{}, warnings []caddyconfig.Warning, always bool) (*caddytls.AutomationPolicy, error) {
-	issuer, hasIssuer := options["cert_issuer"]
+	issuers, hasIssuers := options["cert_issuer"]
 	_, hasLocalCerts := options["local_certs"]
 	keyType, hasKeyType := options["key_type"]
 
-	hasGlobalAutomationOpts := hasIssuer || hasLocalCerts || hasKeyType
+	hasGlobalAutomationOpts := hasIssuers || hasLocalCerts || hasKeyType
 
 	// if there are no global options related to automation policies
 	// set, then we can just return right away
@@ -434,12 +434,12 @@ func newBaseAutomationPolicy(options map[string]interface{}, warnings []caddycon
 		ap.KeyType = keyType.(string)
 	}
 
-	if hasIssuer && hasLocalCerts {
+	if hasIssuers && hasLocalCerts {
 		return nil, fmt.Errorf("global options are ambiguous: local_certs is confusing when combined with cert_issuer, because local_certs is also a specific kind of issuer")
 	}
 
-	if hasIssuer {
-		ap.Issuers = []certmagic.Issuer{issuer.(certmagic.Issuer)}
+	if hasIssuers {
+		ap.Issuers = issuers.([]certmagic.Issuer)
 	} else if hasLocalCerts {
 		ap.Issuers = []certmagic.Issuer{new(caddytls.InternalIssuer)}
 	}