Page Query

Definition

PageQuery is a ​​generic pagination query parameter structure​​ designed to standardize common list query requirements such as pagination and sorting. PageQuery has three fields, PageNumber and PageSize is used to build the paging clause, and Sort is used to build the sorting clause. PageQuery implements the Query interface.

package core

type PageQuery struct {
	PageNumber *int    `json:"page,omitempty"`
	PageSize   *int    `json:"size,omitempty"`
	Sort       *string `json:"sort,omitempty"`
}

Usage

When defining query objects, embed the PageQuery struct through composition to reuse standardized pagination and sorting functionality.

type UserQuery struct {
    PageQuery
    ScoreLt  *int
    MemoNull *bool
    Deleted  *bool
}

Paging

userQuery := UserQuery{PageQuery: PageQuery{}}
users, err := userDataAccess.Query(ctx, userQuery)
//SELECT id, score, memo FROM User

userQuery := UserQuery{PageQuery: PageQuery{PageSize: P(20)}}
users, err := userDataAccess.Query(ctx, userQuery)
//SELECT id, score, memo FROM User LIMIT 20 OFFSET 0

// When only PageNumber is set, PageSize will be set to 10
userQuery := UserQuery{PageQuery: PageQuery{PageNumber: P(5)}}
users, err := userDataAccess.Query(ctx, userQuery)
//SELECT id, score, memo FROM User LIMIT 10 OFFSET 40

userQuery := UserQuery{PageQuery: PageQuery{PageSize: P(50), PageNumber: P(3)}}
users, err := userDataAccess.Query(ctx, userQuery)
//SELECT id, score, memo FROM User LIMIT 10 OFFSET 100	

Sorting

The Sort string should follow regexp.MustCompile("(?i)(\w+)(,(asC|dEsc))?;?")

userQuery := UserQuery{PageQuery: PageQuery{Sort: P("id,desc;score,asc;memo")}}
users, err := userDataAccess.Query(ctx, userQuery)
//SELECT id, score, memo FROM User ORDER BY id DESC, score ASC, memo