gristlabs_grist-core/app/client/ui/App.ts
Dmitry S a91d493ffc (core) Fix issue with 'UNEXPECTED ORDER OF CALLBACKS' in Client.ts.
Summary:
- Substantial refactoring of the logic when the server fails to send some
  messages to a client.
- Add seqId numbers to server messages to ensure reliable order.
- Add a needReload flag in clientConnect for a clear indication whent the
  browser client needs to reload the app.
- Reproduce some potential failure scenarios in a test case (some of which
  previously could have led to incorrectly ordered messages).
- Convert other Comm tests to typescript.
- Tweak logging of Comm and Client to be slightly more concise (in particular,
  avoid logging sessionId)

Note that despite the big refactoring, this only addresses a fairly rare
situation, with websocket failures while server is trying to send to the
client. It includes no improvements for failures while the client is sending to
the server.

(I looked for an existing library that would take care of these issues. A relevant article I found is https://docs.microsoft.com/en-us/azure/azure-web-pubsub/howto-develop-reliable-clients, but it doesn't include a library for both ends, and is still in review. Other libraries with similar purposes did not inspire enough confidence.)

Test Plan: New test cases, which reproduce some previously problematic scenarios.

Reviewers: paulfitz

Reviewed By: paulfitz

Differential Revision: https://phab.getgrist.com/D3470
2022-06-16 23:51:14 -04:00

240 lines
9.3 KiB
TypeScript

import {ClientScope} from 'app/client/components/ClientScope';
import * as Clipboard from 'app/client/components/Clipboard';
import {Comm} from 'app/client/components/Comm';
import * as commandList from 'app/client/components/commandList';
import * as commands from 'app/client/components/commands';
import {unsavedChanges} from 'app/client/components/UnsavedChanges';
import {get as getBrowserGlobals} from 'app/client/lib/browserGlobals';
import {isDesktop} from 'app/client/lib/browserInfo';
import {FocusLayer} from 'app/client/lib/FocusLayer';
import * as koUtil from 'app/client/lib/koUtil';
import {reportError, TopAppModel, TopAppModelImpl} from 'app/client/models/AppModel';
import {DocPageModel} from 'app/client/models/DocPageModel';
import {setUpErrorHandling} from 'app/client/models/errors';
import {createAppUI} from 'app/client/ui/AppUI';
import {addViewportTag} from 'app/client/ui/viewport';
import {attachCssRootVars} from 'app/client/ui2018/cssVars';
import {BaseAPI} from 'app/common/BaseAPI';
import {CommDocError} from 'app/common/CommTypes';
import {DisposableWithEvents} from 'app/common/DisposableWithEvents';
import {fetchFromHome} from 'app/common/urlUtils';
import {ISupportedFeatures} from 'app/common/UserConfig';
import {dom} from 'grainjs';
import * as ko from 'knockout';
// tslint:disable:no-console
const G = getBrowserGlobals('document', 'window');
/**
* Main Grist App UI component.
*/
export class App extends DisposableWithEvents {
// Used by #newui code to avoid a dependency on commands.js, and by tests to issue commands.
public allCommands = commands.allCommands;
public comm = this.autoDispose(Comm.create(this._checkError.bind(this)));
public clientScope: ClientScope;
public features: ko.Computed<ISupportedFeatures>;
public topAppModel: TopAppModel; // Exposed because used by test/nbrowser/gristUtils.
private _settings: ko.Observable<{features?: ISupportedFeatures}>;
// Track the version of the server we are communicating with, so that if it changes
// we can choose to refresh the client also.
private _serverVersion: string|null = null;
// Track the most recently created DocPageModel, for some error handling.
private _mostRecentDocPageModel?: DocPageModel;
constructor() {
super();
commands.init(); // Initialize the 'commands' module using the default command list.
// Create the notifications box, and use it for reporting errors we can catch.
setUpErrorHandling(reportError, koUtil);
this.clientScope = this.autoDispose(ClientScope.create());
// Settings, initialized by initSettings event triggered by a server message.
this._settings = ko.observable({});
this.features = ko.computed(() => this._settings().features || {});
if (isDesktop()) {
this.autoDispose(Clipboard.create(this));
} else {
// On mobile, we do not want to keep focus on a special textarea (which would cause unwanted
// scrolling and showing of mobile keyboard). But we still rely on 'clipboard_focus' and
// 'clipboard_blur' events to know when the "app" has a focus (rather than a particular
// input), by making document.body focusable and using a FocusLayer with it as the default.
document.body.setAttribute('tabindex', '-1');
FocusLayer.create(this, {
defaultFocusElem: document.body,
allowFocus: Clipboard.allowFocus,
onDefaultFocus: () => this.trigger('clipboard_focus'),
onDefaultBlur: () => this.trigger('clipboard_blur'),
});
}
this.topAppModel = this.autoDispose(TopAppModelImpl.create(null, G.window));
const isHelpPaneVisible = ko.observable(false);
G.document.querySelector('#grist-logo-wrapper').remove();
// Help pop-up pane
const helpDiv = document.body.appendChild(
dom('div.g-help',
dom.show(isHelpPaneVisible),
dom('table.g-help-table',
dom('thead',
dom('tr',
dom('th', 'Key'),
dom('th', 'Description')
)
),
dom.forEach(commandList.groups, (group: any) => {
const cmds = group.commands.filter((cmd: any) => Boolean(cmd.desc && cmd.keys.length));
return cmds.length > 0 ?
dom('tbody',
dom('tr',
dom('td', {colspan: 2}, group.group)
),
dom.forEach(cmds, (cmd: any) =>
dom('tr',
dom('td', commands.allCommands[cmd.name].getKeysDom()),
dom('td', cmd.desc)
)
)
) : null;
})
)
)
);
this.onDispose(() => { dom.domDispose(helpDiv); helpDiv.remove(); });
this.autoDispose(commands.createGroup({
help() { G.window.open('help', '_blank').focus(); },
shortcuts() { isHelpPaneVisible(true); },
historyBack() { G.window.history.back(); },
historyForward() { G.window.history.forward(); },
}, this, true));
this.autoDispose(commands.createGroup({
cancel() { isHelpPaneVisible(false); },
cursorDown() { helpDiv.scrollBy(0, 30); }, // 30 is height of the row in the help screen
cursorUp() { helpDiv.scrollBy(0, -30); },
pageUp() { helpDiv.scrollBy(0, -helpDiv.clientHeight); },
pageDown() { helpDiv.scrollBy(0, helpDiv.clientHeight); },
moveToFirstField() { helpDiv.scrollTo(0, 0); }, // home
moveToLastField() { helpDiv.scrollTo(0, helpDiv.scrollHeight); }, // end
find() { return true; }, // restore browser search
help() { isHelpPaneVisible(false); },
}, this, isHelpPaneVisible));
this.listenTo(this.comm, 'clientConnect', (message) => {
console.log(`App clientConnect event: needReload ${message.needReload} version ${message.serverVersion}`);
this._settings(message.settings);
if (message.serverVersion === 'dead' || (this._serverVersion && this._serverVersion !== message.serverVersion)) {
console.log("Upgrading...");
// Server has upgraded. Upgrade client. TODO: be gentle and polite.
return this.reload();
}
this._serverVersion = message.serverVersion;
// Reload any open documents if needed (if clientId changed, or client can't get all missed
// messages). We'll simply reload the active component of the App regardless of what it is.
if (message.needReload) {
this.reloadPane();
}
});
this.listenTo(this.comm, 'connectState', (isConnected: boolean) => {
this.topAppModel.notifier.setConnectState(isConnected);
});
this.listenTo(this.comm, 'docShutdown', () => {
console.log("Received docShutdown");
// Reload on next tick, to let other objects process 'docShutdown' before they get disposed.
setTimeout(() => this.reloadPane(), 0);
});
this.listenTo(this.comm, 'docError', (msg: CommDocError) => {
this._checkError(new Error(msg.data.message));
});
// When the document is unloaded, dispose the app, allowing it to do any needed
// cleanup (e.g. Document on disposal triggers closeDoc message to the server). It needs to be
// in 'beforeunload' rather than 'unload', since websocket is closed by the time of 'unload'.
G.window.addEventListener('beforeunload', (ev: BeforeUnloadEvent) => {
if (unsavedChanges.haveUnsavedChanges()) {
// Following https://developer.mozilla.org/en-US/docs/Web/API/Window/beforeunload_event
const msg = 'You have some unsaved changes';
ev.returnValue = msg;
ev.preventDefault();
return msg;
}
this.dispose();
});
this.comm.initialize(null);
// Add the cssRootVars class to enable the variables in cssVars.
attachCssRootVars(this.topAppModel.productFlavor);
addViewportTag();
this.autoDispose(createAppUI(this.topAppModel, this));
}
// We want to test errors from Selenium, but errors we can trigger using driver.executeScript()
// will be impossible for the application to report properly (they seem to be considered not of
// "same-origin"). So this silly callback is for tests to generate a fake error.
public testTriggerError(msg: string) { throw new Error(msg); }
public reloadPane() {
console.log("reloadPane");
this.topAppModel.reload();
}
// Intended to be used by tests to enable specific features.
public enableFeature(featureName: keyof ISupportedFeatures, onOff: boolean) {
const features = this.features();
features[featureName] = onOff;
this._settings(Object.assign(this._settings(), { features }));
}
public getServerVersion() {
return this._serverVersion;
}
public reload() {
G.window.location.reload(true);
return true;
}
public setDocPageModel(pageModel: DocPageModel) {
this._mostRecentDocPageModel = pageModel;
}
// Get the user profile for testing purposes
public async testGetProfile(): Promise<any> {
const resp = await fetchFromHome('/api/profile/user', {credentials: 'include'});
return resp.json();
}
public testNumPendingApiRequests(): number {
return BaseAPI.numPendingRequests();
}
private _checkError(err: Error) {
const message = String(err);
// Take special action on any error that suggests a memory problem.
if (message.match(/MemoryError|unmarshallable object/)) {
if (err.message.length > 30) {
// TLDR
err.message = 'Memory Error';
}
this._mostRecentDocPageModel?.offerRecovery(err);
}
}
}