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forgejo/models/db/list_options.go
2023-01-17 15:03:44 -06:00

152 lines
3.8 KiB
Go

// Copyright 2020 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package db
import (
"context"
"code.gitea.io/gitea/modules/setting"
"xorm.io/builder"
"xorm.io/xorm"
)
const (
// DefaultMaxInSize represents default variables number on IN () in SQL
DefaultMaxInSize = 50
)
// Paginator is the base for different ListOptions types
type Paginator interface {
GetSkipTake() (skip, take int)
GetStartEnd() (start, end int)
IsListAll() bool
}
// GetPaginatedSession creates a paginated database session
func GetPaginatedSession(p Paginator) *xorm.Session {
skip, take := p.GetSkipTake()
return x.Limit(take, skip)
}
// SetSessionPagination sets pagination for a database session
func SetSessionPagination(sess Engine, p Paginator) *xorm.Session {
skip, take := p.GetSkipTake()
return sess.Limit(take, skip)
}
// SetEnginePagination sets pagination for a database engine
func SetEnginePagination(e Engine, p Paginator) Engine {
skip, take := p.GetSkipTake()
return e.Limit(take, skip)
}
// ListOptions options to paginate results
type ListOptions struct {
PageSize int
Page int // start from 1
ListAll bool // if true, then PageSize and Page will not be taken
}
var _ Paginator = &ListOptions{}
// GetSkipTake returns the skip and take values
func (opts *ListOptions) GetSkipTake() (skip, take int) {
opts.SetDefaultValues()
return (opts.Page - 1) * opts.PageSize, opts.PageSize
}
// GetStartEnd returns the start and end of the ListOptions
func (opts *ListOptions) GetStartEnd() (start, end int) {
start, take := opts.GetSkipTake()
end = start + take
return start, end
}
// IsListAll indicates PageSize and Page will be ignored
func (opts *ListOptions) IsListAll() bool {
return opts.ListAll
}
// SetDefaultValues sets default values
func (opts *ListOptions) SetDefaultValues() {
if opts.PageSize <= 0 {
opts.PageSize = setting.API.DefaultPagingNum
}
if opts.PageSize > setting.API.MaxResponseItems {
opts.PageSize = setting.API.MaxResponseItems
}
if opts.Page <= 0 {
opts.Page = 1
}
}
// AbsoluteListOptions absolute options to paginate results
type AbsoluteListOptions struct {
skip int
take int
}
var _ Paginator = &AbsoluteListOptions{}
// NewAbsoluteListOptions creates a list option with applied limits
func NewAbsoluteListOptions(skip, take int) *AbsoluteListOptions {
if skip < 0 {
skip = 0
}
if take <= 0 {
take = setting.API.DefaultPagingNum
}
if take > setting.API.MaxResponseItems {
take = setting.API.MaxResponseItems
}
return &AbsoluteListOptions{skip, take}
}
// IsListAll will always return false
func (opts *AbsoluteListOptions) IsListAll() bool {
return false
}
// GetSkipTake returns the skip and take values
func (opts *AbsoluteListOptions) GetSkipTake() (skip, take int) {
return opts.skip, opts.take
}
// GetStartEnd returns the start and end values
func (opts *AbsoluteListOptions) GetStartEnd() (start, end int) {
return opts.skip, opts.skip + opts.take
}
// FindOptions represents a find options
type FindOptions interface {
Paginator
ToConds() builder.Cond
}
// Find represents a common find function which accept an options interface
func Find[T any](ctx context.Context, opts FindOptions, objects *[]T) error {
sess := GetEngine(ctx).Where(opts.ToConds())
if !opts.IsListAll() {
sess.Limit(opts.GetSkipTake())
}
return sess.Find(&objects)
}
// Count represents a common count function which accept an options interface
func Count[T any](ctx context.Context, opts FindOptions, object T) (int64, error) {
return GetEngine(ctx).Where(opts.ToConds()).Count(object)
}
// FindAndCount represents a common findandcount function which accept an options interface
func FindAndCount[T any](ctx context.Context, opts FindOptions, objects *[]T) (int64, error) {
sess := GetEngine(ctx).Where(opts.ToConds())
if !opts.IsListAll() {
sess.Limit(opts.GetSkipTake())
}
return sess.FindAndCount(&objects)
}