fix: use typed wireguard public keys in database structs (#2639)

coderd/database/dbtypes/dbtypes.go

@@ -0,0 +1,74 @@
+package dbtypes
+
+import (
+	"database/sql/driver"
+
+	"golang.org/x/xerrors"
+	"tailscale.com/types/key"
+)
+
+// NodePublic is a wrapper around a key.NodePublic which represents the
+// Wireguard public key for an agent..
+type NodePublic key.NodePublic
+
+func (n NodePublic) String() string {
+	return key.NodePublic(n).String()
+}
+
+// This is necessary so NodePublic can be serialized in JSON loggers.
+func (n NodePublic) MarshalJSON() ([]byte, error) {
+	j, err := key.NodePublic(n).MarshalText()
+	// surround in quotes to make it a JSON string
+	j = append([]byte{'"'}, append(j, '"')...)
+	return j, err
+}
+
+// Value is so NodePublic can be inserted into the database.
+func (n NodePublic) Value() (driver.Value, error) {
+	return key.NodePublic(n).MarshalText()
+}
+
+// Scan is so NodePublic can be read from the database.
+func (n *NodePublic) Scan(value interface{}) error {
+	switch v := value.(type) {
+	case []byte:
+		return (*key.NodePublic)(n).UnmarshalText(v)
+	case string:
+		return (*key.NodePublic)(n).UnmarshalText([]byte(v))
+	default:
+		return xerrors.Errorf("unexpected type: %T", v)
+	}
+}
+
+// NodePublic is a wrapper around a key.NodePublic which represents the
+// Tailscale disco key for an agent.
+type DiscoPublic key.DiscoPublic
+
+func (n DiscoPublic) String() string {
+	return key.DiscoPublic(n).String()
+}
+
+// This is necessary so DiscoPublic can be serialized in JSON loggers.
+func (n DiscoPublic) MarshalJSON() ([]byte, error) {
+	j, err := key.DiscoPublic(n).MarshalText()
+	// surround in quotes to make it a JSON string
+	j = append([]byte{'"'}, append(j, '"')...)
+	return j, err
+}
+
+// Value is so DiscoPublic can be inserted into the database.
+func (n DiscoPublic) Value() (driver.Value, error) {
+	return key.DiscoPublic(n).MarshalText()
+}
+
+// Scan is so DiscoPublic can be read from the database.
+func (n *DiscoPublic) Scan(value interface{}) error {
+	switch v := value.(type) {
+	case []byte:
+		return (*key.DiscoPublic)(n).UnmarshalText(v)
+	case string:
+		return (*key.DiscoPublic)(n).UnmarshalText([]byte(v))
+	default:
+		return xerrors.Errorf("unexpected type: %T", v)
+	}
+}