add belongs_to primary_id (aka. primary_key in rails) support (#185)

* pass environments to exec

* revert environment passthru (+1 squashed commit)
Squashed commits:
[6d86b63] allow skip of missing migration due to changing branch

* belongs to support with fk_id

* remove autosave

* added query check (+1 squashed commit)
Squashed commits:
[6c0c3c9] touch up comment (+2 squashed commits)
Squashed commits:
[cfb8124] ensure paginator total entries size works on rawquery
[cce54f7] ensure raw query works with eager

* pagination works with raw query

* case insensitive check limit / offset

* case insensitive check limit / offset

* detect limit or offset by "limit xx,yy"

* support for postgresql FETCH FIRST X rows only

* allow space / tab / new line between limit and offset statements

* Update test.sh

removed sample debug line

* warning message if query contains pagination

* speed up regex matching

* refactor matched sql
reject columns if orderclauses contains ; (multiple query)

* warning indication for invalid order clauses

* made regex private

* add belongs_to primary_id (aka. primary_key in rails)  support

* remove debug

* changed to use indirect to get reflect value without pointer

* Flatten an else after if return

* Fix previous commit

README.md

@@ -459,7 +459,7 @@ type Writer struct {
    ID     uuid.UUID   `db:"id"`
    Name   string      `db:"name"`
    BookID uuid.UUID   `db:"book_id"`
-   Book   Book        `belongs_to:"book"`
+   Book   Book        `belongs_to:"book" fk_id:"BookID" primary_id:"ID"`
 }
 
 type Writers []Writer

associations/belongs_to_association.go

@@ -4,7 +4,9 @@ import (
 	"fmt"
 	"reflect"
 
+	"github.com/gobuffalo/pop/columns"
 	"github.com/gobuffalo/pop/nulls"
+	"github.com/markbates/inflect"
 )
 
 // belongsToAssociation is the implementation for the belongs_to
@@ -14,9 +16,12 @@ type belongsToAssociation struct {
 	ownerType  reflect.Type
 	ownerID    reflect.Value
 	fkID       string
+	primaryID  string
 	ownedModel interface{}
 	*associationSkipable
 	*associationComposite
+
+	primaryTableID string
 }
 
 func init() {
@@ -25,6 +30,11 @@ func init() {
 
 func belongsToAssociationBuilder(p associationParams) (Association, error) {
 	fval := p.modelValue.FieldByName(p.field.Name)
+	primaryIDField := "ID"
+	if p.popTags.Find("primary_id").Value != "" {
+		primaryIDField = p.popTags.Find("primary_id").Value
+	}
+
 	ownerIDField := fmt.Sprintf("%s%s", p.field.Name, "ID")
 	if p.popTags.Find("fk_id").Value != "" {
 		ownerIDField = p.popTags.Find("fk_id").Value
@@ -40,17 +50,34 @@ func belongsToAssociationBuilder(p associationParams) (Association, error) {
 	if fieldIsNil(f) || isZero(f.Interface()) {
 		skipped = true
 	}
+	//associated model
+	ownerPrimaryTableField := "id"
+	if primaryIDField != "ID" {
+		ownerModel := reflect.Indirect(fval)
+		ownerPrimaryField, found := ownerModel.Type().FieldByName(primaryIDField)
+		if !found {
+			return nil, fmt.Errorf("there is no primary field '%s' defined in model '%s'", primaryIDField, ownerModel.Type())
+		}
+		ownerPrimaryTags := columns.TagsFor(ownerPrimaryField)
+		if dbField := ownerPrimaryTags.Find("db").Value; dbField == "" {
+			ownerPrimaryTableField = inflect.Underscore(ownerPrimaryField.Name) //autodetect without db tag
+		} else {
+			ownerPrimaryTableField = dbField
+		}
+	}
 
 	return &belongsToAssociation{
 		ownerModel: fval,
 		ownerType:  fval.Type(),
 		ownerID:    f,
 		fkID:       ownerIDField,
+		primaryID:  primaryIDField,
 		ownedModel: p.model,
 		associationSkipable: &associationSkipable{
 			skipped: skipped,
 		},
 		associationComposite: &associationComposite{innerAssociations: p.innerAssociations},
+		primaryTableID:       ownerPrimaryTableField,
 	}, nil
 }
 
@@ -73,7 +100,7 @@ func (b *belongsToAssociation) Interface() interface{} {
 // Constraint returns the content for a where clause, and the args
 // needed to execute it.
 func (b *belongsToAssociation) Constraint() (string, []interface{}) {
-	return "id = ?", []interface{}{b.ownerID.Interface()}
+	return fmt.Sprintf("%s = ?", b.primaryTableID), []interface{}{b.ownerID.Interface()}
 }
 
 func (b *belongsToAssociation) BeforeInterface() interface{} {

columns/tags.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 )
 
-var tags = "db rw select belongs_to has_many has_one fk_id order_by many_to_many"
+var tags = "db rw select belongs_to has_many has_one fk_id primary_id order_by many_to_many"
 
 // Tag represents a field tag defined exclusively for pop package.
 type Tag struct {

finders_test.go

@@ -120,7 +120,7 @@ func Test_Find_Eager_Belongs_To(t *testing.T) {
 	transaction(func(tx *pop.Connection) {
 		r := require.New(t)
 
-		user := User{Name: nulls.NewString("Mark")}
+		user := User{Name: nulls.NewString("Mark"), UserName: "mark"}
 		err := tx.Create(&user)
 		r.NoError(err)
 
@@ -135,6 +135,15 @@ func Test_Find_Eager_Belongs_To(t *testing.T) {
 		r.NotEqual(b.ID, 0)
 		r.NotEqual(b.User.ID, 0)
 		r.Equal(b.User.ID, user.ID)
+
+		userAttr := UserAttribute{UserName: "mark", NickName: "Mark Z."}
+		err = tx.Create(&userAttr)
+		r.NoError(err)
+
+		uA := UserAttribute{}
+		err = tx.Eager().Find(&uA, userAttr.ID)
+		r.NoError(err)
+		r.Equal(uA.User.ID, user.ID)
 	})
 }
 

migrations/20160808213308_setup_tests.down.fizz

@@ -4,4 +4,5 @@ drop_table("validatable_cars")
 drop_table("not_validatable_cars")
 drop_table("callbacks_users")
 drop_table("books")
-drop_table("cars")
+drop_table("cars")
+drop_table("user_attributes")

migrations/20160808213308_setup_tests.up.fizz

@@ -1,5 +1,6 @@
 create_table("users") {
   t.Column("name", "string", {})
+  t.Column("user_name", "string", {"size": 100})
   t.Column("alive", "boolean", {"null": true})
   t.Column("birth_date", "timestamp", {"null": true})
   t.Column("bio", "text", {"null": true})
@@ -36,3 +37,8 @@ create_table("taxis") {
   t.Column("model", "string", {})
   t.Column("user_id", "int", {"null": true})
 }
+create_table("user_attributes") {
+  t.Column("user_name", "string", {"size": 100})
+  t.Column("nick_name", "string", {})
+  t.DisableTimestamps()
+}

pop_test.go

@@ -67,6 +67,7 @@ func ts(s string) string {
 
 type User struct {
 	ID           int           `db:"id"`
+	UserName     string        `db:"user_name"`
 	Email        string        `db:"email"`
 	Name         nulls.String  `db:"name"`
 	Alive        nulls.Bool    `db:"alive"`
@@ -91,6 +92,14 @@ func (u *User) Validate(tx *pop.Connection) (*validate.Errors, error) {
 
 type Users []User
 
+type UserAttribute struct {
+	ID       int    `db:"id"`
+	UserName string `db:"user_name"`
+	NickName string `db:"nick_name"`
+
+	User User `json:"user" belongs_to:"user" fk_id:"UserName" primary_id:"UserName"`
+}
+
 type Book struct {
 	ID          int       `db:"id"`
 	Title       string    `db:"title"`

query_test.go

@@ -120,7 +120,7 @@ func Test_ToSQL(t *testing.T) {
 	transaction(func(tx *pop.Connection) {
 		user := &pop.Model{Value: &User{}}
 
-		s := "SELECT name as full_name, users.alive, users.bio, users.birth_date, users.created_at, users.email, users.id, users.name, users.price, users.updated_at FROM users AS users"
+		s := "SELECT name as full_name, users.alive, users.bio, users.birth_date, users.created_at, users.email, users.id, users.name, users.price, users.updated_at, users.user_name FROM users AS users"
 
 		query := pop.Q(tx)
 		q, _ := query.ToSQL(user)
@@ -131,7 +131,7 @@ func Test_ToSQL(t *testing.T) {
 		a.Equal(fmt.Sprintf("%s ORDER BY id desc", s), q)
 
 		q, _ = query.ToSQL(&pop.Model{Value: &User{}, As: "u"})
-		a.Equal("SELECT name as full_name, u.alive, u.bio, u.birth_date, u.created_at, u.email, u.id, u.name, u.price, u.updated_at FROM users AS u ORDER BY id desc", q)
+		a.Equal("SELECT name as full_name, u.alive, u.bio, u.birth_date, u.created_at, u.email, u.id, u.name, u.price, u.updated_at, u.user_name FROM users AS u ORDER BY id desc", q)
 
 		q, _ = query.ToSQL(&pop.Model{Value: &Family{}})
 		a.Equal("SELECT family_members.created_at, family_members.first_name, family_members.id, family_members.last_name, family_members.updated_at FROM family.members AS family_members ORDER BY id desc", q)