Add email format type (#191)

* Add email format type

* Add email to internal test schema

Author: harryrford

email.go

@@ -0,0 +1,27 @@
+package types
+
+import (
+	"encoding/json"
+	"errors"
+)
+
+type Email string
+
+func (e Email) MarshalJSON() ([]byte, error) {
+	if !emailRegex.MatchString(string(e)) {
+		return nil, errors.New("email: failed to pass regex validation")
+	}
+	return json.Marshal(string(e))
+}
+
+func (e *Email) UnmarshalJSON(data []byte) error {
+	var s string
+	if err := json.Unmarshal(data, &s); err != nil {
+		return err
+	}
+	if !emailRegex.MatchString(s) {
+		return errors.New("email: failed to pass regex validation")
+	}
+	*e = Email(s)
+	return nil
+}

email_test.go

@@ -0,0 +1,31 @@
+package types
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestEmail_MarshalJSON(t *testing.T) {
+	testEmail := "gaben@valvesoftware.com"
+	b := struct {
+		EmailField Email `json:"email"`
+	}{
+		EmailField: Email(testEmail),
+	}
+	jsonBytes, err := json.Marshal(b)
+	assert.NoError(t, err)
+	assert.JSONEq(t, `{"email":"gaben@valvesoftware.com"}`, string(jsonBytes))
+}
+
+func TestEmail_UnmarshalJSON(t *testing.T) {
+	testEmail := Email("gaben@valvesoftware.com")
+	jsonStr := `{"email":"gaben@valvesoftware.com"}`
+	b := struct {
+		EmailField Email `json:"email"`
+	}{}
+	err := json.Unmarshal([]byte(jsonStr), &b)
+	assert.NoError(t, err)
+	assert.Equal(t, testEmail, b.EmailField)
+}

regexes.go

@@ -0,0 +1,11 @@
+package types
+
+import "regexp"
+
+const (
+	emailRegexString = "^(?:(?:(?:(?:[a-zA-Z]|\\d|[!#\\$%&'\\*\\+\\-\\/=\\?\\^_`{\\|}~]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])+(?:\\.([a-zA-Z]|\\d|[!#\\$%&'\\*\\+\\-\\/=\\?\\^_`{\\|}~]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])+)*)|(?:(?:\\x22)(?:(?:(?:(?:\\x20|\\x09)*(?:\\x0d\\x0a))?(?:\\x20|\\x09)+)?(?:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x7f]|\\x21|[\\x23-\\x5b]|[\\x5d-\\x7e]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])|(?:(?:[\\x01-\\x09\\x0b\\x0c\\x0d-\\x7f]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}]))))*(?:(?:(?:\\x20|\\x09)*(?:\\x0d\\x0a))?(\\x20|\\x09)+)?(?:\\x22))))@(?:(?:(?:[a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])|(?:(?:[a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])(?:[a-zA-Z]|\\d|-|\\.|~|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])*(?:[a-zA-Z]|\\d|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])))\\.)+(?:(?:[a-zA-Z]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])|(?:(?:[a-zA-Z]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])(?:[a-zA-Z]|\\d|-|\\.|~|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])*(?:[a-zA-Z]|[\\x{00A0}-\\x{D7FF}\\x{F900}-\\x{FDCF}\\x{FDF0}-\\x{FFEF}])))\\.?$"
+)
+
+var (
+	emailRegex = regexp.MustCompile(emailRegexString)
+)