Domain block (#76)

* start work on admin domain blocking

* move stuff around + further work on domain blocks

* move + restructure processor

* prep work for deleting account

* tidy

* go fmt

* formatting

* domain blocking more work

* check domain blocks way earlier on

* progress on delete account

* delete more stuff when an account is gone

* and more...

* domain blocky block block

* get individual domain block, delete a block

internal/federation/util.go

@@ -0,0 +1,23 @@
+package federation
+
+import (
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+)
+
+func (f *federator) blockedDomain(host string) (bool, error) {
+	b := &gtsmodel.DomainBlock{}
+	err := f.db.GetWhere([]db.Where{{Key: "domain", Value: host, CaseInsensitive: true}}, b)
+	if err == nil {
+		// block exists
+		return true, nil
+	}
+
+	if _, ok := err.(db.ErrNoEntries); ok {
+		// there are no entries so there's no block
+		return false, nil
+	}
+
+	// there's an actual error
+	return false, err
+}