Implement database/sql's Scanner interface. Fixes #5
diff --git a/sql.go b/sql.go
new file mode 100644
index 0000000..2d7679e
--- /dev/null
+++ b/sql.go
@@ -0,0 +1,40 @@
+// Copyright 2015 Google Inc. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package uuid
+
+import (
+ "errors"
+ "fmt"
+)
+
+// Scan implements sql.Scanner so UUIDs can be read from databases transparently
+// Currently, database types that map to string and []byte are supported. Please
+// consult database-specific driver documentation for matching types.
+func (uuid *UUID) Scan(src interface{}) error {
+ switch src.(type) {
+ case string:
+ // see uuid.Parse for required string format
+ parsed := Parse(src.(string))
+
+ if parsed == nil {
+ return errors.New("Scan: invalid UUID format")
+ }
+
+ *uuid = parsed
+ case []byte:
+ // assumes a simple slice of bytes, just check validity and store
+ u := UUID(src.([]byte))
+
+ if u.Variant() == Invalid {
+ return errors.New("Scan: invalid UUID format")
+ }
+
+ *uuid = u
+ default:
+ return fmt.Errorf("Scan: unable to scan type %T into UUID", src)
+ }
+
+ return nil
+}
diff --git a/sql_test.go b/sql_test.go
new file mode 100644
index 0000000..d643567
--- /dev/null
+++ b/sql_test.go
@@ -0,0 +1,53 @@
+// Copyright 2015 Google Inc. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package uuid
+
+import (
+ "strings"
+ "testing"
+)
+
+func TestScan(t *testing.T) {
+ var stringTest string = "f47ac10b-58cc-0372-8567-0e02b2c3d479"
+ var byteTest []byte = Parse(stringTest)
+ var badTypeTest int = 6
+ var invalidTest string = "f47ac10b-58cc-0372-8567-0e02b2c3d4"
+ var invalidByteTest []byte = Parse(invalidTest)
+
+ var uuid UUID
+ err := (&uuid).Scan(stringTest)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ err = (&uuid).Scan(byteTest)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ err = (&uuid).Scan(badTypeTest)
+ if err == nil {
+ t.Error("int correctly parsed and shouldn't have")
+ }
+ if !strings.Contains(err.Error(), "unable to scan type") {
+ t.Error("attempting to parse an int returned an incorrect error message")
+ }
+
+ err = (&uuid).Scan(invalidTest)
+ if err == nil {
+ t.Error("invalid uuid was parsed without error")
+ }
+ if !strings.Contains(err.Error(), "invalid UUID") {
+ t.Error("attempting to parse an invalid UUID returned an incorrect error message")
+ }
+
+ err = (&uuid).Scan(invalidByteTest)
+ if err == nil {
+ t.Error("invalid byte uuid was parsed without error")
+ }
+ if !strings.Contains(err.Error(), "invalid UUID") {
+ t.Error("attempting to parse an invalid byte UUID returned an incorrect error message")
+ }
+}
