diff --git a/utils/pagination/controller.go b/utils/pagination/controller.go new file mode 100644 index 00000000..28473f8a --- /dev/null +++ b/utils/pagination/controller.go @@ -0,0 +1,26 @@ +// Copyright 2014 beego Author. All Rights Reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package pagination + +import ( + "github.com/astaxie/beego/context" +) + +// Instantiates a Paginator and assigns it to context.Input.Data["paginator"]. +func SetPaginator(context *context.Context, per int, nums int64) (paginator *Paginator) { + paginator = NewPaginator(context.Request, per, nums) + context.Input.Data["paginator"] = paginator + return +} diff --git a/utils/pagination/doc.go b/utils/pagination/doc.go new file mode 100644 index 00000000..df0fa3b7 --- /dev/null +++ b/utils/pagination/doc.go @@ -0,0 +1,59 @@ +/* + +The pagination package provides utilities to setup a paginator within the +context of a http request. + +Usage + +In your beego.Controller: + + package controllers + + import "github.com/astaxie/beego/utils/pagination" + + type PostsController struct { + beego.Controller + } + + func (this *PostsController) ListAllPosts() { + // sets this.Data["paginator"] with the current offset (from the url query param) + postsPerPage := 20 + paginator := pagination.SetPaginator(this.Ctx, postsPerPage, CountPosts()) + + // fetch the next 20 posts + this.Data["posts"] = ListPostsByOffsetAndLimit(paginator.Offset(), postsPerPage) + } + + +In your view templates: + + {{if .paginator.HasPages}} + + {{end}} + +See also + +http://beego.me/docs/mvc/view/page.md + +*/ +package pagination diff --git a/utils/pagination/paginator.go b/utils/pagination/paginator.go new file mode 100644 index 00000000..f89e878e --- /dev/null +++ b/utils/pagination/paginator.go @@ -0,0 +1,189 @@ +// Copyright 2014 beego Author. All Rights Reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package pagination + +import ( + "math" + "net/http" + "net/url" + "strconv" +) + +// Paginator within the state of a http request. +type Paginator struct { + Request *http.Request + PerPageNums int + MaxPages int + + nums int64 + pageRange []int + pageNums int + page int +} + +// Returns the total number of pages. +func (p *Paginator) PageNums() int { + if p.pageNums != 0 { + return p.pageNums + } + pageNums := math.Ceil(float64(p.nums) / float64(p.PerPageNums)) + if p.MaxPages > 0 { + pageNums = math.Min(pageNums, float64(p.MaxPages)) + } + p.pageNums = int(pageNums) + return p.pageNums +} + +// Returns the total number of items (e.g. from doing SQL count). +func (p *Paginator) Nums() int64 { + return p.nums +} + +// Sets the total number of items. +func (p *Paginator) SetNums(nums interface{}) { + p.nums, _ = ToInt64(nums) +} + +// Returns the current page. +func (p *Paginator) Page() int { + if p.page != 0 { + return p.page + } + if p.Request.Form == nil { + p.Request.ParseForm() + } + p.page, _ = strconv.Atoi(p.Request.Form.Get("p")) + if p.page > p.PageNums() { + p.page = p.PageNums() + } + if p.page <= 0 { + p.page = 1 + } + return p.page +} + +// Returns a list of all pages. +// +// Usage (in a view template): +// +// {{range $index, $page := .paginator.Pages}} +// +// {{$page}} +// +// {{end}} +func (p *Paginator) Pages() []int { + if p.pageRange == nil && p.nums > 0 { + var pages []int + pageNums := p.PageNums() + page := p.Page() + switch { + case page >= pageNums-4 && pageNums > 9: + start := pageNums - 9 + 1 + pages = make([]int, 9) + for i, _ := range pages { + pages[i] = start + i + } + case page >= 5 && pageNums > 9: + start := page - 5 + 1 + pages = make([]int, int(math.Min(9, float64(page+4+1)))) + for i, _ := range pages { + pages[i] = start + i + } + default: + pages = make([]int, int(math.Min(9, float64(pageNums)))) + for i, _ := range pages { + pages[i] = i + 1 + } + } + p.pageRange = pages + } + return p.pageRange +} + +// Returns URL for a given page index. +func (p *Paginator) PageLink(page int) string { + link, _ := url.ParseRequestURI(p.Request.RequestURI) + values := link.Query() + if page == 1 { + values.Del("p") + } else { + values.Set("p", strconv.Itoa(page)) + } + link.RawQuery = values.Encode() + return link.String() +} + +// Returns URL to the previous page. +func (p *Paginator) PageLinkPrev() (link string) { + if p.HasPrev() { + link = p.PageLink(p.Page() - 1) + } + return +} + +// Returns URL to the next page. +func (p *Paginator) PageLinkNext() (link string) { + if p.HasNext() { + link = p.PageLink(p.Page() + 1) + } + return +} + +// Returns URL to the first page. +func (p *Paginator) PageLinkFirst() (link string) { + return p.PageLink(1) +} + +// Returns URL to the last page. +func (p *Paginator) PageLinkLast() (link string) { + return p.PageLink(p.PageNums()) +} + +// Returns true if the current page has a predecessor. +func (p *Paginator) HasPrev() bool { + return p.Page() > 1 +} + +// Returns true if the current page has a successor. +func (p *Paginator) HasNext() bool { + return p.Page() < p.PageNums() +} + +// Returns true if the given page index points to the current page. +func (p *Paginator) IsActive(page int) bool { + return p.Page() == page +} + +// Returns the current offset. +func (p *Paginator) Offset() int { + return (p.Page() - 1) * p.PerPageNums +} + +// Returns true if there is more than one page. +func (p *Paginator) HasPages() bool { + return p.PageNums() > 1 +} + +// Instantiates a paginator struct for the current http request. +func NewPaginator(req *http.Request, per int, nums interface{}) *Paginator { + p := Paginator{} + p.Request = req + if per <= 0 { + per = 10 + } + p.PerPageNums = per + p.SetNums(nums) + return &p +} diff --git a/utils/pagination/utils.go b/utils/pagination/utils.go new file mode 100644 index 00000000..5932647d --- /dev/null +++ b/utils/pagination/utils.go @@ -0,0 +1,34 @@ +// Copyright 2014 beego Author. All Rights Reserved. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package pagination + +import ( + "fmt" + "reflect" +) + +// convert any numeric value to int64 +func ToInt64(value interface{}) (d int64, err error) { + val := reflect.ValueOf(value) + switch value.(type) { + case int, int8, int16, int32, int64: + d = val.Int() + case uint, uint8, uint16, uint32, uint64: + d = int64(val.Uint()) + default: + err = fmt.Errorf("ToInt64 need numeric not `%T`", value) + } + return +}