adding local pagination to bucket list (#5684)

* adding local pagination to bucket list

When there are more than 5000 buckets, browser ui
becomes unresponsive since react needs to create
5000 elements which takes browser resources.
So we show only 100 buckets for the first time,
and load more buckets when the user is scrolling down.

* move inline styles to less file

browser/app/js/buckets/BucketList.js

@@ -17,14 +17,28 @@
 import React from "react"
 import { connect } from "react-redux"
 import { Scrollbars } from "react-custom-scrollbars"
+import InfiniteScroll from "react-infinite-scroller"
 import * as actionsBuckets from "./actions"
-import { getVisibleBuckets } from "./selectors"
+import { getFilteredBuckets } from "./selectors"
 import BucketContainer from "./BucketContainer"
 import web from "../web"
 import history from "../history"
 import { pathSlice } from "../utils"
 
 export class BucketList extends React.Component {
+  constructor(props) {
+    super(props)
+    this.state = {
+      page: 1
+    }
+  }
+  componentWillReceiveProps(nexProps) {
+    if (this.props.filter != nexProps.filter) {
+      this.setState({
+        page: 1
+      })
+    }
+  }
   componentWillMount() {
     const { fetchBuckets, setBucketList, selectBucket } = this.props
     if (web.LoggedIn()) {
@@ -39,13 +53,29 @@ export class BucketList extends React.Component {
       }
     }
   }
+  loadNextPage() {
+    this.setState({
+      page: this.state.page + 1
+    })
+  }
   render() {
-    const { visibleBuckets } = this.props
+    const { filteredBuckets } = this.props
+    const visibleBuckets = filteredBuckets.slice(0, this.state.page * 100)
     return (
       <div className="buckets__list">
-        {visibleBuckets.map(bucket => (
-          <BucketContainer key={bucket} bucket={bucket} />
-        ))}
+        <InfiniteScroll
+          pageStart={0}
+          loadMore={this.loadNextPage.bind(this)}
+          hasMore={filteredBuckets.length > visibleBuckets.length}
+          useWindow={false}
+          element="div"
+          initialLoad={false}
+          className="buckets__scroll"
+        >
+          {visibleBuckets.map(bucket => (
+            <BucketContainer key={bucket} bucket={bucket} />
+          ))}
+        </InfiniteScroll>
       </div>
     )
   }
@@ -53,7 +83,8 @@ export class BucketList extends React.Component {
 
 const mapStateToProps = state => {
   return {
-    visibleBuckets: getVisibleBuckets(state),
+    filteredBuckets: getFilteredBuckets(state),
+    filter: state.buckets.filter
   }
 }
 
@@ -61,7 +92,7 @@ const mapDispatchToProps = dispatch => {
   return {
     fetchBuckets: () => dispatch(actionsBuckets.fetchBuckets()),
     setBucketList: buckets => dispatch(actionsBuckets.setList(buckets)),
-    selectBucket: bucket => dispatch(actionsBuckets.selectBucket(bucket)),
+    selectBucket: bucket => dispatch(actionsBuckets.selectBucket(bucket))
   }
 }
 

browser/app/js/buckets/__tests__/selectors.test.js

@@ -14,25 +14,25 @@
  * limitations under the License.
  */
 
-import { getVisibleBuckets, getCurrentBucket } from "../selectors"
+import { getFilteredBuckets, getCurrentBucket } from "../selectors"
 
-describe("getVisibleBuckets", () => {
+describe("getFilteredBuckets", () => {
   let state
   beforeEach(() => {
     state = {
       buckets: {
-        list: ["test1", "test11", "test2"],
-      },
+        list: ["test1", "test11", "test2"]
+      }
     }
   })
 
   it("should return all buckets if no filter specified", () => {
     state.buckets.filter = ""
-    expect(getVisibleBuckets(state)).toEqual(["test1", "test11", "test2"])
+    expect(getFilteredBuckets(state)).toEqual(["test1", "test11", "test2"])
   })
 
   it("should return all matching buckets if filter is specified", () => {
     state.buckets.filter = "test1"
-    expect(getVisibleBuckets(state)).toEqual(["test1", "test11"])
+    expect(getFilteredBuckets(state)).toEqual(["test1", "test11"])
   })
 })

browser/app/js/buckets/selectors.js

@@ -19,7 +19,7 @@ import { createSelector } from "reselect"
 const bucketsSelector = state => state.buckets.list
 const bucketsFilterSelector = state => state.buckets.filter
 
-export const getVisibleBuckets = createSelector(
+export const getFilteredBuckets = createSelector(
   bucketsSelector,
   bucketsFilterSelector,
   (buckets, filter) => buckets.filter(bucket => bucket.indexOf(filter) > -1),

browser/app/less/inc/sidebar.less

@@ -82,6 +82,11 @@
     margin-bottom: 1rem;
 }
 
+.buckets__list {
+    height: calc(~"100vh - 246px");
+    overflow: auto;
+}
+
 .buckets__item {
     padding: 0.8rem @sidebar-padding 0.8rem @sidebar-padding*2.2;
     background: url(../../img/icons/bucket.svg) no-repeat left 2.2rem center;