Merge remote-tracking branch 'origin/v2'

.circleci/config.yml

@@ -16,6 +16,17 @@ default: &default
         MYSQL_USER: pageboy
         MYSQL_PASSWORD: pageboy
         MYSQL_ROOT_PASSWORD: pageboy
+    - image: postgres:13.0
+      <<: *dockerhub_auth
+      environment:
+        POSTGRES_DB: pageboy
+        POSTGRES_USER: pageboy
+        POSTGRES_PASSWORD: pageboy
+    - image: mcmoe/mssqldocker:v2019.CU4.0
+      <<: *dockerhub_auth
+      environment:
+        ACCEPT_EULA: Y
+        SA_PASSWORD: hXUeLZvM4p3r2XeBG
 
 jobs:
   build:
@@ -42,6 +53,26 @@ jobs:
               sleep 1
             done
             echo Failed waiting for MySQL && exit 1
+      - run:
+          name: Waiting for PostgresSQL to be ready
+          command: |
+            for i in `seq 1 10`;
+            do
+              nc -z localhost 5432 && echo Success && exit 0
+              echo -n .
+              sleep 1
+            done
+            echo Failed waiting for PostgresSQL && exit 1
+      - run:
+          name: Waiting for SQLServer to be ready
+          command: |
+            for i in `seq 1 10`;
+            do
+              nc -z localhost 1433 && echo Success && exit 0
+              echo -n .
+              sleep 1
+            done
+            echo Failed waiting for SQLServer && exit 1
       - run: make test
 
 workflows:
@@ -54,4 +85,3 @@ workflows:
           context: org-global
       - test:
           context: org-global
-

Makefile

@@ -3,8 +3,12 @@ build:
 	go build
 
 test:
-	DB=sqlite go test ./... -count=1
-	DB=mysql go test ./... -count=1
+	go test ./core/... -count=1
+	cd tests; \
+		DB=sqlite    go test ./... -count=1 && \
+		DB=mysql     go test ./... -count=1 && \
+		DB=postgres  go test ./... -count=1 && \
+		DB=sqlserver go test ./... -count=1
 
 format:
 	gofmt -w ./

README.md

@@ -13,13 +13,15 @@ pageboy
   - Like them: `?page=1&per_page=2` and `?before=1585706584&limit=10`
   - We can also customize it if needed.
 - 💖　We can write smart code using GORM scopes.
+- 👌　Supports all DB engine officialy supported by GORM.
+  - MySQL, PostgreSQL, SQLite, SQL Server
 
 ## Installation
 
 To install it, run:
 
 ```bash
-go get -u github.com/soranoba/pageboy
+go get -u github.com/soranoba/pageboy/v2
 ```
 
 ## Usage
@@ -47,7 +49,7 @@ You should create an index when using a Cursor.<br>
 Example using CreatedAt and ID for sorting:
 
 ```sql
-CREATE INDEX created_at_id ON `users` (`created_at` DESC, `id` DESC);
+CREATE INDEX created_at_id ON users (created_at DESC, id DESC);
 ```
 
 #### Usage in Codes
@@ -76,6 +78,17 @@ func getUsers(ctx echo.Context) error {
 }
 ```
 
+#### NULLS FIRST / NULLS LAST
+
+PostgresSQL can accept NULLS FIRST or NULLS LAST for index.<br>
+In that case, it can use the index by adding NULLS FIRST or NULLS LAST in Order.
+
+It is not supported other engines because they cannot accept these for index.
+
+```go
+cursor.Paginate("CreatedAt", "UpdatedAt").Order("DESC NULLS LAST", "ASC NULLS FIRST").Scope()
+```
+
 ### Pager
 
 Pager can be used to indicate a range that is specified a page size and a page number.

core/comparison.go

@@ -18,71 +18,79 @@ const (
 	LessThan Comparison = "<"
 )
 
-// MakeComparisonScopeBuildFunc returns a GORM scope builder.
+// MakeComparisonScope returns a GORM scope builder.
 // This scope add a where clauses filtered by comparisons ranges.
-func MakeComparisonScopeBuildFunc(columns ...string) func(comparisons ...Comparison) func(values ...interface{}) func(*gorm.DB) *gorm.DB {
-	return func(comparisons ...Comparison) func(values ...interface{}) func(*gorm.DB) *gorm.DB {
-		if len(columns) != len(comparisons) {
-			panic("columns and comparisons must have the same length")
-		}
+func MakeComparisonScope(columns []string, comparisons []Comparison, nullsOrders []NullsOrder, values []interface{}) func(*gorm.DB) *gorm.DB {
+	if len(columns) != len(comparisons) {
+		panic("columns and comparisons must have the same length")
+	}
+	if len(columns) != len(nullsOrders) {
+		panic("columns and nullsOrders must have the same length")
+	}
 
-		return func(values ...interface{}) func(*gorm.DB) *gorm.DB {
-			return func(db *gorm.DB) *gorm.DB {
-				queryValues := make([]interface{}, 0)
-				nonNilValues := make([]interface{}, 0)
-				queries := make([]string, 0)
-				var eqQuery string
+	return func(db *gorm.DB) *gorm.DB {
+		queryValues := make([]interface{}, 0)
+		nonNilValues := make([]interface{}, 0)
+		queries := make([]string, 0)
+		var eqQuery string
 
-				var length = (func() int {
-					if len(values) > len(columns) {
-						return len(columns)
-					}
-					return len(values)
-				})()
+		length := (func() int {
+			if len(values) > len(columns) {
+				return len(columns)
+			}
+			return len(values)
+		})()
 
-				comparisons = comparisons[0:length]
-				for i := len(comparisons); i < length; i++ {
-					if i == 0 {
-						comparisons = append(comparisons, GreaterThan)
-					} else {
-						comparisons = append(comparisons, comparisons[i-1])
-					}
-				}
+		comparisons = comparisons[0:length]
+		for i := len(comparisons); i < length; i++ {
+			if i == 0 {
+				comparisons = append(comparisons, GreaterThan)
+			} else {
+				comparisons = append(comparisons, comparisons[i-1])
+			}
+		}
+
+		isPostgres := (db.Dialector.Name() == "postgres")
 
-			Loop:
-				for i, column := range columns[:length] {
-					column = toSnake(column)
+	Loop:
+		for i, column := range columns[:length] {
+			column = toSnake(column)
 
-					val := reflect.ValueOf(values[i])
-					isNil := val.Kind() == reflect.Ptr && val.IsNil()
+			nullsOrder := nullsOrders[i]
+			if nullsOrder == TreatsAsEngineDefault {
+				if isPostgres {
+					nullsOrder = TreatsAsHighest
+				} else {
+					nullsOrder = TreatsAsLowest
+				}
+			}
 
-					switch comparisons[i] {
-					case LessThan:
-						if isNil {
-							eqQuery += fmt.Sprintf("`%s` IS NULL AND ", column)
-							continue Loop
-						} else {
-							query := fmt.Sprintf("(%s(`%s` IS NULL OR `%s` %s ?))", eqQuery, column, column, comparisons[i])
-							queries = append(queries, query)
-						}
-					case GreaterThan:
-						if isNil {
-							eqQuery += fmt.Sprintf("`%s` IS NOT NULL OR ", column)
-							continue Loop
-						} else {
-							query := fmt.Sprintf("(%s`%s` %s ?)", eqQuery, column, comparisons[i])
-							queries = append(queries, query)
-						}
-					default:
-						panic("Unsupported compareStr")
-					}
+			val := reflect.ValueOf(values[i])
+			isNil := val.Kind() == reflect.Ptr && val.IsNil()
 
-					eqQuery += fmt.Sprintf("`%s` = ? AND ", column)
-					nonNilValues = append(nonNilValues, values[i])
-					queryValues = append(queryValues, nonNilValues...)
+			if (comparisons[i] == LessThan && nullsOrder == TreatsAsLowest) ||
+				(comparisons[i] == GreaterThan && nullsOrder == TreatsAsHighest) {
+				if isNil {
+					eqQuery += fmt.Sprintf("%s IS NULL AND ", column)
+					continue Loop
+				} else {
+					query := fmt.Sprintf("(%s(%s IS NULL OR %s %s ?))", eqQuery, column, column, comparisons[i])
+					queries = append(queries, query)
+				}
+			} else {
+				if isNil {
+					eqQuery += fmt.Sprintf("%s IS NOT NULL OR ", column)
+					continue Loop
+				} else {
+					query := fmt.Sprintf("(%s%s %s ?)", eqQuery, column, comparisons[i])
+					queries = append(queries, query)
 				}
-				return db.Where("("+strings.Join(queries, " OR ")+")", queryValues...)
 			}
+
+			eqQuery += fmt.Sprintf("%s = ? AND ", column)
+			nonNilValues = append(nonNilValues, values[i])
+			queryValues = append(queryValues, nonNilValues...)
 		}
+		return db.Where("("+strings.Join(queries, " OR ")+")", queryValues...)
 	}
 }

core/nulls_order.go

@@ -0,0 +1,13 @@
+package core
+
+// NullsOrder is how to handle null values when sorting.
+type NullsOrder int
+
+const (
+	// TreatsAsEngineDefault is the default behavior of the engine.
+	TreatsAsEngineDefault NullsOrder = iota
+	// TreatsAsLowest is that Null values are treated as the lowest.
+	TreatsAsLowest
+	// TreatsAsHighest is that Null values are treated as the highest.
+	TreatsAsHighest
+)

core/order.go

@@ -16,29 +16,27 @@ const (
 )
 
 // OrderClauseBuilder returns a function that create ORDER BY clause to specifies the order of DB records.
-func OrderClauseBuilder(columns ...string) func(orders ...Order) string {
-	return func(orders ...Order) string {
+func OrderClauseBuilder(columns ...string) func(orders ...string) string {
+	return func(orders ...string) string {
 		if len(columns) != len(orders) {
 			panic("columns and orders must have the same length")
 		}
 
 		parts := make([]string, len(columns))
 		for i, column := range columns {
-			parts[i] = fmt.Sprintf("`%s` %s", toSnake(column), strings.ToUpper(string(orders[i])))
+			parts[i] = fmt.Sprintf("%s %s", toSnake(column), strings.ToUpper(string(orders[i])))
 		}
 		return strings.Join(parts, ", ")
 	}
 }
 
-// ReverseOrders returns a slice of Order converted from ASC to DESC, DESC to ASC.
-func ReverseOrders(orders []Order) []Order {
-	newOrders := make([]Order, len(orders))
+// ReverseOrders returns a slice of Order converted from ASC to DESC, DESC to ASC, FIRST to LAST, LAST to FIRST.
+func ReverseOrders(orders []string) []string {
+	replacer := strings.NewReplacer("ASC", "DESC", "DESC", "ASC", "FIRST", "LAST", "LAST", "FIRST")
+	newOrders := make([]string, len(orders))
 	for i := 0; i < len(orders); i++ {
-		if orders[i] == ASC {
-			newOrders[i] = DESC
-		} else {
-			newOrders[i] = ASC
-		}
+		order := strings.ToUpper(orders[i])
+		newOrders[i] = replacer.Replace(order)
 	}
 	return newOrders
 }

core/order_test.go

@@ -5,21 +5,21 @@ import (
 )
 
 func ExampleOrderClauseBuilder() {
-	fmt.Printf("%s\n", OrderClauseBuilder("ID", "CreatedAt")(ASC, ASC))
-	fmt.Printf("%s\n", OrderClauseBuilder("ID", "CreatedAt")(DESC, DESC))
-	fmt.Printf("%s\n", OrderClauseBuilder("ID", "CreatedAt")(ASC, DESC))
+	fmt.Printf("%s\n", OrderClauseBuilder("ID", "CreatedAt")("asc", "ASC"))
+	fmt.Printf("%s\n", OrderClauseBuilder("ID", "CreatedAt")("desc", "DESC"))
+	fmt.Printf("%s\n", OrderClauseBuilder("ID", "CreatedAt")("ASC", "desc"))
 
 	// Output:
-	// `id` ASC, `created_at` ASC
-	// `id` DESC, `created_at` DESC
-	// `id` ASC, `created_at` DESC
+	// id ASC, created_at ASC
+	// id DESC, created_at DESC
+	// id ASC, created_at DESC
 }
 
 func ExampleReverseOrders() {
-	fmt.Printf("%v\n", ReverseOrders([]Order{ASC, DESC, DESC}))
-	fmt.Printf("%v\n", ReverseOrders([]Order{DESC, ASC, ASC}))
+	fmt.Printf("%#v\n", ReverseOrders([]string{"asc", "DESC", "desc nulls first"}))
+	fmt.Printf("%#v\n", ReverseOrders([]string{"DESC", "asc", "ASC NULLS LAST"}))
 
 	// Output:
-	// [desc asc asc]
-	// [asc desc desc]
+	// []string{"DESC", "ASC", "ASC NULLS LAST"}
+	// []string{"ASC", "DESC", "DESC NULLS FIRST"}
 }