fix pagination

src/assets/index.html

@@ -260,7 +260,7 @@
                         <div>{{ item.title || 'untitled' }}</div>
                     </div>
                 </label>
-                <button class="btn btn-link btn-block loading my-3" v-if="itemsPage.cur < itemsPage.num"></button>
+                <button class="btn btn-link btn-block loading my-3" v-if="itemsHasMore"></button>
             </div>
             <div class="px-3 py-2 border-top text-danger text-break" v-if="feed_errors[current.feed.id]">
                 {{ feed_errors[current.feed.id] }}

src/assets/javascripts/app.js

@@ -180,7 +180,7 @@ var vm = new Vue({
   created: function() {
     this.refreshStats()
       .then(this.refreshFeeds.bind(this))
-      .then(this.refreshItems.bind(this))
+      .then(this.refreshItems.bind(this, false))
 
     api.feeds.list_errors().then(function(errors) {
       vm.feed_errors = errors
@@ -197,10 +197,7 @@ var vm = new Vue({
       'feedNewChoice': [],
       'feedNewChoiceSelected': '',
       'items': [],
-      'itemsPage': {
-        'cur': 1,
-        'num': 1,
-      },
+      'itemsHasMore': true,
       'itemSelected': null,
       'itemSelectedDetails': null,
       'itemSelectedReadability': '',
@@ -304,13 +301,13 @@ var vm = new Vue({
     },
     'filterSelected': function(newVal, oldVal) {
       if (oldVal === undefined) return  // do nothing, initial setup
-      api.settings.update({filter: newVal}).then(this.refreshItems.bind(this))
+      api.settings.update({filter: newVal}).then(this.refreshItems.bind(this, false))
       this.itemSelected = null
       this.computeStats()
     },
     'feedSelected': function(newVal, oldVal) {
       if (oldVal === undefined) return  // do nothing, initial setup
-      api.settings.update({feed: newVal}).then(this.refreshItems.bind(this))
+      api.settings.update({feed: newVal}).then(this.refreshItems.bind(this, false))
       this.itemSelected = null
       if (this.$refs.itemlist) this.$refs.itemlist.scrollTop = 0
     },
@@ -339,7 +336,7 @@ var vm = new Vue({
     }, 500),
     'itemSortNewestFirst': function(newVal, oldVal) {
       if (oldVal === undefined) return  // do nothing, initial setup
-      api.settings.update({sort_newest_first: newVal}).then(this.refreshItems.bind(this))
+      api.settings.update({sort_newest_first: newVal}).then(vm.refreshItems.bind(this, false))
     },
     'feedListWidth': debounce(function(newVal, oldVal) {
       if (oldVal === undefined) return  // do nothing, initial setup
@@ -404,34 +401,34 @@ var vm = new Vue({
           vm.feeds = values[1]
         })
     },
-    refreshItems: function() {
+    refreshItems: function(loadMore) {
       if (this.feedSelected === null) {
         vm.items = []
-        vm.itemsPage = {'cur': 1, 'num': 1}
         return
       }
+
       var query = this.getItemsQuery()
+      if (loadMore) {
+        query.after = vm.items[vm.items.length-1].id
+      }
+
       this.loading.items = true
       return api.items.list(query).then(function(data) {
+        if (loadMore) {
+          vm.items = vm.items.concat(data.list)
+        } else {
           vm.items = data.list
-        vm.itemsPage = data.page
+        }
+        vm.itemsHasMore = data.has_more
         vm.loading.items = false
       })
     },
     loadMoreItems: function(event, el) {
-      if (this.itemsPage.cur >= this.itemsPage.num) return
+      if (!this.itemsHasMore) return
+
       if (this.loading.items) return
       var closeToBottom = (el.scrollHeight - el.scrollTop - el.offsetHeight) < 50
-      if (closeToBottom) {
-        this.loading.moreitems = true
-        var query = this.getItemsQuery()
-        query.page = this.itemsPage.cur + 1
-        api.items.list(query).then(function(data) {
-          vm.items = vm.items.concat(data.list)
-          vm.itemsPage = data.page
-          vm.loading.items = false
-        })
-      }
+      if (closeToBottom) this.refreshItems(true)
     },
     markItemsRead: function() {
       var query = this.getItemsQuery()

src/server/routes.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"log"
-	"math"
 	"net/http"
 	"path/filepath"
 	"reflect"
@@ -307,11 +306,8 @@ func (s *Server) handleItem(c *router.Context) {
 func (s *Server) handleItemList(c *router.Context) {
 	if c.Req.Method == "GET" {
 		perPage := 20
-		curPage := 1
 		query := c.Req.URL.Query()
-		if page, err := c.QueryInt64("page"); err == nil {
-			curPage = int(page)
-		}
+
 		filter := storage.ItemFilter{}
 		if folderID, err := c.QueryInt64("folder_id"); err == nil {
 			filter.FolderID = &folderID
@@ -319,6 +315,9 @@ func (s *Server) handleItemList(c *router.Context) {
 		if feedID, err := c.QueryInt64("feed_id"); err == nil {
 			filter.FeedID = &feedID
 		}
+		if after, err := c.QueryInt64("after"); err == nil {
+			filter.After = &after
+		}
 		if status := query.Get("status"); len(status) != 0 {
 			statusValue := storage.StatusValues[status]
 			filter.Status = &statusValue
@@ -327,14 +326,16 @@ func (s *Server) handleItemList(c *router.Context) {
 			filter.Search = &search
 		}
 		newestFirst := query.Get("oldest_first") != "true"
-		items := s.db.ListItems(filter, (curPage-1)*perPage, perPage, newestFirst)
-		count := s.db.CountItems(filter)
+
+		items := s.db.ListItems(filter, perPage+1, newestFirst)
+		hasMore := false
+		if len(items) == perPage+1 {
+			hasMore = true
+			items = items[:perPage]
+		}
 		c.JSON(http.StatusOK, map[string]interface{}{
-			"page": map[string]int{
-				"cur": curPage,
-				"num": int(math.Ceil(float64(count) / float64(perPage))),
-			},
 			"list": items,
+			"has_more": hasMore,
 		})
 	} else if c.Req.Method == "PUT" {
 		filter := storage.MarkFilter{}

src/storage/item.go

@@ -61,6 +61,7 @@ type ItemFilter struct {
 	FeedID   *int64
 	Status   *ItemStatus
 	Search   *string
+	After  *int64
 }
 
 type MarkFilter struct {
@@ -106,7 +107,7 @@ func (s *Storage) CreateItems(items []Item) bool {
 	return true
 }
 
-func listQueryPredicate(filter ItemFilter) (string, []interface{}) {
+func listQueryPredicate(filter ItemFilter, newestFirst bool) (string, []interface{}) {
 	cond := make([]string, 0)
 	args := make([]interface{}, 0)
 	if filter.FolderID != nil {
@@ -131,6 +132,14 @@ func listQueryPredicate(filter ItemFilter) (string, []interface{}) {
 		cond = append(cond, "i.search_rowid in (select rowid from search where search match ?)")
 		args = append(args, strings.Join(terms, " "))
 	}
+	if filter.After != nil {
+		compare := ">"
+		if newestFirst {
+			compare = "<"
+		}
+		cond = append(cond, fmt.Sprintf("(i.date, i.id) %s (select date, id from items where id = ?)", compare))
+		args = append(args, *filter.After)
+	}
 
 	predicate := "1"
 	if len(cond) > 0 {
@@ -140,13 +149,13 @@ func listQueryPredicate(filter ItemFilter) (string, []interface{}) {
 	return predicate, args
 }
 
-func (s *Storage) ListItems(filter ItemFilter, offset, limit int, newestFirst bool) []Item {
-	predicate, args := listQueryPredicate(filter)
+func (s *Storage) ListItems(filter ItemFilter, limit int, newestFirst bool) []Item {
+	predicate, args := listQueryPredicate(filter, newestFirst)
 	result := make([]Item, 0, 0)
 
-	order := "date desc"
+	order := "date desc, id desc"
 	if !newestFirst {
-		order = "date asc"
+		order = "date asc, id asc"
 	}
 
 	query := fmt.Sprintf(`
@@ -157,8 +166,8 @@ func (s *Storage) ListItems(filter ItemFilter, offset, limit int, newestFirst bo
 		from items i
 		where %s
 		order by %s
-		limit %d offset %d
-		`, predicate, order, limit, offset)
+		limit %d
+		`, predicate, order, limit)
 	rows, err := s.db.Query(query, args...)
 	if err != nil {
 		log.Print(err)
@@ -199,28 +208,13 @@ func (s *Storage) GetItem(id int64) *Item {
 	return i
 }
 
-func (s *Storage) CountItems(filter ItemFilter) int64 {
-	predicate, args := listQueryPredicate(filter)
-	query := fmt.Sprintf(`
-		select count(i.id)
-		from items i
-		where %s`, predicate)
-	row := s.db.QueryRow(query, args...)
-	if row != nil {
-		var result int64
-		row.Scan(&result)
-		return result
-	}
-	return 0
-}
-
 func (s *Storage) UpdateItemStatus(item_id int64, status ItemStatus) bool {
 	_, err := s.db.Exec(`update items set status = ? where id = ?`, status, item_id)
 	return err == nil
 }
 
 func (s *Storage) MarkItemsRead(filter MarkFilter) bool {
-	predicate, args := listQueryPredicate(ItemFilter{FolderID: filter.FolderID, FeedID: filter.FeedID})
+	predicate, args := listQueryPredicate(ItemFilter{FolderID: filter.FolderID, FeedID: filter.FeedID}, false)
 	query := fmt.Sprintf(`
 		update items as i set status = %d
 		where %s and i.status != %d