Preload logs when scrolled to top

Signed-off-by: Alex Andreev <alex.andreev.email@gmail.com>

src/renderer/components/+workloads-pods/pod-menu.tsx

@@ -51,7 +51,6 @@ export class PodMenu extends React.Component<Props> {
       selectedContainer: container,
       showTimestamps: false,
       previous: false,
-      tailLines: 1000
     });
   }
 

src/renderer/components/dock/pod-logs.store.ts

@@ -1,10 +1,11 @@
-import { autorun, observable } from "mobx";
-import { Pod, IPodContainer, podsApi } from "../../api/endpoints";
+import { autorun, computed, observable } from "mobx";
+import { Pod, IPodContainer, podsApi, IPodLogsQuery } from "../../api/endpoints";
 import { autobind, interval } from "../../utils";
 import { DockTabStore } from "./dock-tab.store";
 import { dockStore, IDockTab, TabKind } from "./dock.store";
 import { t } from "@lingui/macro";
 import { _i18n } from "../../i18n";
+import { Notifications } from "../notifications";
 
 export interface IPodLogsData {
   pod: Pod;
@@ -12,20 +13,22 @@ export interface IPodLogsData {
   containers: IPodContainer[]
   initContainers: IPodContainer[]
   showTimestamps: boolean
-  tailLines: number
   previous: boolean
 }
 
 type TabId = string;
+type PodLogs = string;
 
-interface PodLogs {
-  oldLogs?: string
-  newLogs?: string
-}
+// Number for log lines to load
+export const logRange = 100; // TODO: Change to 1000 for production
 
 @autobind()
 export class PodLogsStore extends DockTabStore<IPodLogsData> {
-  private refresher = interval(10, () => this.load(dockStore.selectedTabId));
+  private refresher = interval(10, () => {
+    const id = dockStore.selectedTabId
+    if (!this.logs.get(id)) return
+    this.loadMore(id)
+  });
 
   @observable logs = observable.map<TabId, PodLogs>();
 
@@ -43,45 +46,85 @@ export class PodLogsStore extends DockTabStore<IPodLogsData> {
     }, { delay: 500 });
   }
 
+  /**
+   * Function prepares tailLines param for passing to API request
+   * Each time it increasing it's number, caused to fetch more logs.
+   * Also, it handles loading errors, rewriting whole logs with error
+   * messages
+   * @param tabId
+   */
   load = async (tabId: TabId) => {
-    if (!this.logs.has(tabId)) {
-      this.logs.set(tabId, { oldLogs: "", newLogs: "" })
-    }
-    const data = this.getData(tabId);
-    const { oldLogs, newLogs } = this.logs.get(tabId);
-    const { selectedContainer, tailLines, previous } = data;
-    const pod = new Pod(data.pod);
-    try {
-      // if logs already loaded, check the latest timestamp for getting updates only from this point
-      const logsTimestamps = this.getTimestamps(newLogs || oldLogs);
-      let lastLogDate = new Date(0);
-      if (logsTimestamps) {
-        lastLogDate = new Date(logsTimestamps.slice(-1)[0]);
-        lastLogDate.setSeconds(lastLogDate.getSeconds() + 1); // avoid duplicates from last second
-      }
-      const namespace = pod.getNs();
-      const name = pod.getName();
-      const loadedLogs = await podsApi.getLogs({ namespace, name }, {
-        sinceTime: lastLogDate.toISOString(),
-        timestamps: true,  // Always setting timestampt to separate old logs from new ones
-        container: selectedContainer.name,
-        tailLines,
-        previous
-      });
-      if (!oldLogs) {
-        this.logs.set(tabId, { oldLogs: loadedLogs, newLogs });
-      } else {
-        this.logs.set(tabId, { oldLogs, newLogs: loadedLogs });
-      }
-    } catch ({error}) {
-      this.logs.set(tabId, {
-        oldLogs: [
+    const logs = await this.loadLogs(tabId, {
+      tailLines: this.lines + logRange
+    })
+      .then(logs => {
+        if (!this.refresher.isRunning) this.refresher.start();
+        return logs;
+      })
+      .catch(({error}) => {
+        const message = [
           _i18n._(t`Failed to load logs: ${error.message}`),
           _i18n._(t`Reason: ${error.reason} (${error.code})`)
-        ].join("\n"),
-        newLogs
+        ].join("\n");
+        this.refresher.stop();
+        Notifications.error(message);
+        return message;
       });
+    this.logs.set(tabId, logs);
+  }
+
+  /**
+   * Function is used to refreser/stream-like requests.
+   * It changes 'sinceTime' param each time allowing to fetch logs
+   * starting from last line recieved.
+   * @param tabId
+   */
+  loadMore = async (tabId: TabId) => {
+    const oldLogs = this.logs.get(tabId);
+    const timestamps = this.getTimestamps(oldLogs);
+    let sinceTime = new Date(0);
+    if (timestamps) {
+      sinceTime = new Date(timestamps.slice(-1)[0]);
+      sinceTime.setSeconds(sinceTime.getSeconds() + 1); // avoid duplicates from last second
     }
+    const logs = await this.loadLogs(tabId, {
+      sinceTime: sinceTime.toISOString()
+    });
+    // Add newly received logs to bottom
+    // TODO: set a new log separator here
+    this.logs.set(tabId, oldLogs + logs);
+  }
+
+  /**
+   * Main logs loading function adds necessary data to payload and makes
+   * an API request
+   * @param tabId
+   * @param params request parameters described in IPodLogsQuery interface
+   * @returns {Promise} A fetch request promise
+   */
+  loadLogs = async (tabId: TabId, params: Partial<IPodLogsQuery>) => {
+    const data = this.getData(tabId);
+    const { selectedContainer, previous } = data;
+    const pod = new Pod(data.pod);
+    const namespace = pod.getNs();
+    const name = pod.getName();
+    return await podsApi.getLogs({ namespace, name }, {
+      ...params,
+      timestamps: true,  // Always setting timestampt to separate old logs from new ones
+      container: selectedContainer.name,
+      previous
+    });
+  }
+
+  /**
+   * Converts logs into a string array
+   * @returns {number} Length of log lines
+   */
+  @computed
+  get lines() {
+    const id = dockStore.selectedTabId;
+    const logs = this.logs.get(id);
+    return logs ? logs.split("\n").length : 0;
   }
 
   getTimestamps(logs: string) {

src/renderer/components/dock/pod-logs.tsx

@@ -12,7 +12,7 @@ import { Select, SelectOption } from "../select";
 import { Spinner } from "../spinner";
 import { IDockTab } from "./dock.store";
 import { InfoPanel } from "./info-panel";
-import { IPodLogsData, podLogsStore } from "./pod-logs.store";
+import { IPodLogsData, logRange, podLogsStore } from "./pod-logs.store";
 
 interface Props {
   className?: string
@@ -22,16 +22,11 @@ interface Props {
 @observer
 export class PodLogs extends React.Component<Props> {
   @observable ready = false;
+  @observable preloading = false; // Indicator for setting Spinner (loader) at the top of the logs
 
   private logsElement: HTMLDivElement;
   private lastLineIsShown = true; // used for proper auto-scroll content after refresh
   private colorConverter = new AnsiUp();
-  private lineOptions = [
-    { label: _i18n._(t`All logs`), value: Number.MAX_SAFE_INTEGER },
-    { label: 1000, value: 1000 },
-    { label: 10000, value: 10000 },
-    { label: 100000, value: 100000 },
-  ];
 
   componentDidMount() {
     disposeOnUnmount(this,
@@ -78,22 +73,40 @@ export class PodLogs extends React.Component<Props> {
     await this.load();
   }
 
+  /**
+   * Function loads more logs (usually after user scrolls to top) and sets proper
+   * scrolling position
+   * @param scrollHeight previous scrollHeight position before adding new lines
+   */
+  preload = async (scrollHeight: number) => {
+    if (podLogsStore.lines < logRange) return;
+    this.preloading = true;
+    await podLogsStore.load(this.tabId).then(() => this.preloading = false);
+    if (this.logsElement.scrollHeight > scrollHeight) {
+      // Set scroll position back to place where preloading started
+      this.logsElement.scrollTop = this.logsElement.scrollHeight - scrollHeight - 48;
+    }
+  }
+
+  /**
+   * Computed prop which returns logs with or without timestamps added to each line
+   */
   @computed
   get logs() {
     if (!podLogsStore.logs.has(this.tabId)) return;
-    const { oldLogs, newLogs } = podLogsStore.logs.get(this.tabId);
+    const logs = podLogsStore.logs.get(this.tabId);
     const { getData, removeTimestamps } = podLogsStore;
     const { showTimestamps } = getData(this.tabId);
-    return {
-      oldLogs: showTimestamps ? oldLogs : removeTimestamps(oldLogs),
-      newLogs: showTimestamps ? newLogs : removeTimestamps(newLogs)
-    }
+    return showTimestamps ? logs : removeTimestamps(logs);
   }
 
   toggleTimestamps = () => {
     this.save({ showTimestamps: !this.tabData.showTimestamps });
   }
 
+  /**
+   * Setting 'previous' param to load API request fetching logs from previous container
+   */
   togglePrevious = () => {
     this.save({ previous: !this.tabData.previous });
     this.reload();
@@ -102,15 +115,16 @@ export class PodLogs extends React.Component<Props> {
   onScroll = (evt: React.UIEvent<HTMLDivElement>) => {
     const logsArea = evt.currentTarget;
     const { scrollHeight, clientHeight, scrollTop } = logsArea;
+    if (scrollTop === 0) {
+      this.preload(scrollHeight);
+    }
     this.lastLineIsShown = clientHeight + scrollTop === scrollHeight;
   };
 
   downloadLogs = () => {
-    const { oldLogs, newLogs } = this.logs;
     const { pod, selectedContainer } = this.tabData;
     const fileName = selectedContainer ? selectedContainer.name : pod.getName();
-    const fileContents = oldLogs + newLogs;
-    downloadFile(fileName + ".log", fileContents, "text/plain");
+    downloadFile(fileName + ".log", this.logs, "text/plain");
   }
 
   onContainerChange = (option: SelectOption) => {
@@ -123,11 +137,6 @@ export class PodLogs extends React.Component<Props> {
     this.reload();
   }
 
-  onTailLineChange = (option: SelectOption) => {
-    this.save({ tailLines: option.value })
-    this.reload();
-  }
-
   get containerSelectOptions() {
     const { containers, initContainers } = this.tabData;
     return [
@@ -153,8 +162,8 @@ export class PodLogs extends React.Component<Props> {
 
   renderControls() {
     if (!this.ready) return null;
-    const { selectedContainer, showTimestamps, tailLines, previous } = this.tabData;
-    const timestamps = podLogsStore.getTimestamps(podLogsStore.logs.get(this.tabId).oldLogs);
+    const { selectedContainer, showTimestamps, previous } = this.tabData;
+    const timestamps = podLogsStore.getTimestamps(podLogsStore.logs.get(this.tabId));
     return (
       <div className="controls flex gaps align-center">
         <span><Trans>Container</Trans></span>
@@ -165,12 +174,6 @@ export class PodLogs extends React.Component<Props> {
           onChange={this.onContainerChange}
           autoConvertOptions={false}
         />
-        <span><Trans>Lines</Trans></span>
-        <Select
-          value={tailLines}
-          options={this.lineOptions}
-          onChange={this.onTailLineChange}
-        />
         <div className="time-range">
           {timestamps && (
             <>
@@ -203,11 +206,11 @@ export class PodLogs extends React.Component<Props> {
   }
 
   renderLogs() {
+    const newLogs = false // TODO: set new logs separator and generate new logs
     if (!this.ready) {
       return <Spinner center/>;
     }
-    const { oldLogs, newLogs } = this.logs;
-    if (!oldLogs && !newLogs) {
+    if (!this.logs) {
       return (
         <div className="flex align-center justify-center">
           <Trans>There are no logs available for container.</Trans>
@@ -216,7 +219,12 @@ export class PodLogs extends React.Component<Props> {
     }
     return (
       <>
-        <div dangerouslySetInnerHTML={{ __html: DOMPurify.sanitize(this.colorConverter.ansi_to_html(oldLogs))}} />
+        {this.preloading && (
+          <div className="flex justify-center">
+            <Spinner />
+          </div>
+        )}
+        <div dangerouslySetInnerHTML={{ __html: DOMPurify.sanitize(this.colorConverter.ansi_to_html(this.logs))}} />
         {newLogs && (
           <>
             <p className="new-logs-sep" title={_i18n._(t`New logs since opening the dialog`)}/>