/
context.ts
907 lines (832 loc) · 24.1 KB
/
context.ts
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// Copyright (c) Jupyter Development Team.
// Distributed under the terms of the Modified BSD License.
import {
Contents,
ServiceManager,
ServerConnection
} from '@jupyterlab/services';
import { PromiseDelegate, PartialJSONValue } from '@lumino/coreutils';
import { IDisposable, DisposableDelegate } from '@lumino/disposable';
import { ISignal, Signal } from '@lumino/signaling';
import { Widget } from '@lumino/widgets';
import {
showDialog,
SessionContext,
Dialog,
ISessionContext,
showErrorMessage
} from '@jupyterlab/apputils';
import { PathExt } from '@jupyterlab/coreutils';
import { IModelDB, ModelDB } from '@jupyterlab/observables';
import { RenderMimeRegistry } from '@jupyterlab/rendermime';
import { IRenderMime } from '@jupyterlab/rendermime-interfaces';
import { DocumentRegistry } from './registry';
/**
* An implementation of a document context.
*
* This class is typically instantiated by the document manager.
*/
export class Context<T extends DocumentRegistry.IModel>
implements DocumentRegistry.IContext<T> {
/**
* Construct a new document context.
*/
constructor(options: Context.IOptions<T>) {
let manager = (this._manager = options.manager);
this._factory = options.factory;
this._opener = options.opener || Private.noOp;
this._path = this._manager.contents.normalize(options.path);
const localPath = this._manager.contents.localPath(this._path);
let lang = this._factory.preferredLanguage(PathExt.basename(localPath));
let dbFactory = options.modelDBFactory;
if (dbFactory) {
const localPath = manager.contents.localPath(this._path);
this._modelDB = dbFactory.createNew(localPath);
this._model = this._factory.createNew(lang, this._modelDB);
} else {
this._model = this._factory.createNew(lang);
}
this._readyPromise = manager.ready.then(() => {
return this._populatedPromise.promise;
});
let ext = PathExt.extname(this._path);
this.sessionContext = new SessionContext({
sessionManager: manager.sessions,
specsManager: manager.kernelspecs,
path: this._path,
type: ext === '.ipynb' ? 'notebook' : 'file',
name: PathExt.basename(localPath),
kernelPreference: options.kernelPreference || { shouldStart: false },
setBusy: options.setBusy
});
this.sessionContext.propertyChanged.connect(this._onSessionChanged, this);
manager.contents.fileChanged.connect(this._onFileChanged, this);
this.urlResolver = new RenderMimeRegistry.UrlResolver({
session: this.sessionContext,
contents: manager.contents
});
}
/**
* A signal emitted when the path changes.
*/
get pathChanged(): ISignal<this, string> {
return this._pathChanged;
}
/**
* A signal emitted when the model is saved or reverted.
*/
get fileChanged(): ISignal<this, Contents.IModel> {
return this._fileChanged;
}
/**
* A signal emitted on the start and end of a saving operation.
*/
get saveState(): ISignal<this, DocumentRegistry.SaveState> {
return this._saveState;
}
/**
* A signal emitted when the context is disposed.
*/
get disposed(): ISignal<this, void> {
return this._disposed;
}
/**
* Get the model associated with the document.
*/
get model(): T {
return this._model;
}
/**
* The client session object associated with the context.
*/
readonly sessionContext: SessionContext;
/**
* The current path associated with the document.
*/
get path(): string {
return this._path;
}
/**
* The current local path associated with the document.
* If the document is in the default notebook file browser,
* this is the same as the path.
*/
get localPath(): string {
return this._manager.contents.localPath(this._path);
}
/**
* The current contents model associated with the document.
*
* #### Notes
* The contents model will be null until the context is populated.
* It will have an empty `contents` field.
*/
get contentsModel(): Contents.IModel | null {
return this._contentsModel;
}
/**
* Get the model factory name.
*
* #### Notes
* This is not part of the `IContext` API.
*/
get factoryName(): string {
return this.isDisposed ? '' : this._factory.name;
}
/**
* Test whether the context is disposed.
*/
get isDisposed(): boolean {
return this._isDisposed;
}
/**
* Dispose of the resources held by the context.
*/
dispose(): void {
if (this.isDisposed) {
return;
}
this._isDisposed = true;
this.sessionContext.dispose();
if (this._modelDB) {
this._modelDB.dispose();
}
this._model.dispose();
this._disposed.emit(void 0);
Signal.clearData(this);
}
/**
* Whether the context is ready.
*/
get isReady(): boolean {
return this._isReady;
}
/**
* A promise that is fulfilled when the context is ready.
*/
get ready(): Promise<void> {
return this._readyPromise;
}
/**
* The url resolver for the context.
*/
readonly urlResolver: IRenderMime.IResolver;
/**
* Initialize the context.
*
* @param isNew - Whether it is a new file.
*
* @returns a promise that resolves upon initialization.
*/
initialize(isNew: boolean): Promise<void> {
if (isNew) {
this._model.initialize();
return this._save();
}
if (this._modelDB) {
return this._modelDB.connected.then(() => {
if (this._modelDB.isPrepopulated) {
this._model.initialize();
void this._save();
return void 0;
} else {
return this._revert(true);
}
});
} else {
return this._revert(true);
}
}
/**
* Save the document contents to disk.
*/
save(): Promise<void> {
return this.ready.then(() => {
return this._save();
});
}
/**
* Save the document to a different path chosen by the user.
*/
saveAs(): Promise<void> {
return this.ready
.then(() => {
return Private.getSavePath(this._path);
})
.then(newPath => {
if (this.isDisposed || !newPath) {
return;
}
if (newPath === this._path) {
return this.save();
}
// Make sure the path does not exist.
return this._manager.ready
.then(() => {
return this._manager.contents.get(newPath);
})
.then(() => {
return this._maybeOverWrite(newPath);
})
.catch(err => {
if (!err.response || err.response.status !== 404) {
throw err;
}
return this._finishSaveAs(newPath);
});
});
}
/**
* Download a file.
*
* @param path - The path of the file to be downloaded.
*
* @returns A promise which resolves when the file has begun
* downloading.
*/
async download(): Promise<void> {
const url = await this._manager.contents.getDownloadUrl(this._path);
let element = document.createElement('a');
element.href = url;
element.download = '';
document.body.appendChild(element);
element.click();
document.body.removeChild(element);
return void 0;
}
/**
* Revert the document contents to disk contents.
*/
revert(): Promise<void> {
return this.ready.then(() => {
return this._revert();
});
}
/**
* Create a checkpoint for the file.
*/
createCheckpoint(): Promise<Contents.ICheckpointModel> {
let contents = this._manager.contents;
return this._manager.ready.then(() => {
return contents.createCheckpoint(this._path);
});
}
/**
* Delete a checkpoint for the file.
*/
deleteCheckpoint(checkpointId: string): Promise<void> {
let contents = this._manager.contents;
return this._manager.ready.then(() => {
return contents.deleteCheckpoint(this._path, checkpointId);
});
}
/**
* Restore the file to a known checkpoint state.
*/
restoreCheckpoint(checkpointId?: string): Promise<void> {
let contents = this._manager.contents;
let path = this._path;
return this._manager.ready.then(() => {
if (checkpointId) {
return contents.restoreCheckpoint(path, checkpointId);
}
return this.listCheckpoints().then(checkpoints => {
if (this.isDisposed || !checkpoints.length) {
return;
}
checkpointId = checkpoints[checkpoints.length - 1].id;
return contents.restoreCheckpoint(path, checkpointId);
});
});
}
/**
* List available checkpoints for a file.
*/
listCheckpoints(): Promise<Contents.ICheckpointModel[]> {
let contents = this._manager.contents;
return this._manager.ready.then(() => {
return contents.listCheckpoints(this._path);
});
}
/**
* Add a sibling widget to the document manager.
*
* @param widget - The widget to add to the document manager.
*
* @param options - The desired options for adding the sibling.
*
* @returns A disposable used to remove the sibling if desired.
*
* #### Notes
* It is assumed that the widget has the same model and context
* as the original widget.
*/
addSibling(
widget: Widget,
options: DocumentRegistry.IOpenOptions = {}
): IDisposable {
let opener = this._opener;
if (opener) {
opener(widget, options);
}
return new DisposableDelegate(() => {
widget.close();
});
}
/**
* Handle a change on the contents manager.
*/
private _onFileChanged(
sender: Contents.IManager,
change: Contents.IChangedArgs
): void {
if (change.type !== 'rename') {
return;
}
let oldPath = change.oldValue && change.oldValue.path;
let newPath = change.newValue && change.newValue.path;
if (newPath && this._path.indexOf(oldPath || '') === 0) {
let changeModel = change.newValue;
// When folder name changed, `oldPath` is `foo`, `newPath` is `bar` and `this._path` is `foo/test`,
// we should update `foo/test` to `bar/test` as well
if (oldPath !== this._path) {
newPath = this._path.replace(new RegExp(`^${oldPath}/`), `${newPath}/`);
oldPath = this._path;
// Update client file model from folder change
changeModel = {
last_modified: change.newValue?.created,
path: newPath
};
}
this._path = newPath;
void this.sessionContext.session?.setPath(newPath);
const updateModel = {
...this._contentsModel,
...changeModel
};
const localPath = this._manager.contents.localPath(newPath);
void this.sessionContext.session?.setName(PathExt.basename(localPath));
this._updateContentsModel(updateModel as Contents.IModel);
this._pathChanged.emit(this._path);
}
}
/**
* Handle a change to a session property.
*/
private _onSessionChanged(sender: ISessionContext, type: string): void {
if (type !== 'path') {
return;
}
let path = this.sessionContext.session!.path;
if (path !== this._path) {
this._path = path;
this._pathChanged.emit(path);
}
}
/**
* Update our contents model, without the content.
*/
private _updateContentsModel(model: Contents.IModel): void {
let newModel: Contents.IModel = {
path: model.path,
name: model.name,
type: model.type,
content: undefined,
writable: model.writable,
created: model.created,
last_modified: model.last_modified,
mimetype: model.mimetype,
format: model.format
};
let mod = this._contentsModel ? this._contentsModel.last_modified : null;
this._contentsModel = newModel;
if (!mod || newModel.last_modified !== mod) {
this._fileChanged.emit(newModel);
}
}
/**
* Handle an initial population.
*/
private _populate(): Promise<void> {
this._isPopulated = true;
this._isReady = true;
this._populatedPromise.resolve(void 0);
// Add a checkpoint if none exists and the file is writable.
return this._maybeCheckpoint(false).then(() => {
if (this.isDisposed) {
return;
}
// Update the kernel preference.
let name =
this._model.defaultKernelName ||
this.sessionContext.kernelPreference.name;
this.sessionContext.kernelPreference = {
...this.sessionContext.kernelPreference,
name,
language: this._model.defaultKernelLanguage
};
// Note: we don't wait on the session to initialize
// so that the user can be shown the content before
// any kernel has started.
void this.sessionContext.initialize();
});
}
/**
* Save the document contents to disk.
*/
private _save(): Promise<void> {
this._saveState.emit('started');
let model = this._model;
let content: PartialJSONValue;
if (this._factory.fileFormat === 'json') {
content = model.toJSON();
} else {
content = model.toString();
if (this._useCRLF) {
content = content.replace(/\n/g, '\r\n');
}
}
let options = {
type: this._factory.contentType,
format: this._factory.fileFormat,
content
};
return this._manager.ready
.then(() => {
if (!model.modelDB.isCollaborative) {
return this._maybeSave(options);
}
return this._manager.contents.save(this._path, options);
})
.then(value => {
if (this.isDisposed) {
return;
}
model.dirty = false;
this._updateContentsModel(value);
if (!this._isPopulated) {
return this._populate();
}
})
.catch(err => {
// If the save has been canceled by the user,
// throw the error so that whoever called save()
// can decide what to do.
if (err.message === 'Cancel') {
throw err;
}
// Otherwise show an error message and throw the error.
const localPath = this._manager.contents.localPath(this._path);
const name = PathExt.basename(localPath);
void this._handleError(err, `File Save Error for ${name}`);
throw err;
})
.then(
value => {
// Capture all success paths and emit completion.
this._saveState.emit('completed');
return value;
},
err => {
// Capture all error paths and emit failure.
this._saveState.emit('failed');
throw err;
}
)
.catch(() => {
/* no-op */
});
}
/**
* Revert the document contents to disk contents.
*
* @param initializeModel - call the model's initialization function after
* deserializing the content.
*/
private _revert(initializeModel: boolean = false): Promise<void> {
let opts: Contents.IFetchOptions = {
format: this._factory.fileFormat,
type: this._factory.contentType,
content: true
};
let path = this._path;
let model = this._model;
return this._manager.ready
.then(() => {
return this._manager.contents.get(path, opts);
})
.then(contents => {
if (this.isDisposed) {
return;
}
let dirty = false;
if (contents.format === 'json') {
model.fromJSON(contents.content);
if (initializeModel) {
model.initialize();
}
} else {
let content = contents.content;
// Convert line endings if necessary, marking the file
// as dirty.
if (content.indexOf('\r') !== -1) {
this._useCRLF = true;
content = content.replace(/\r\n/g, '\n');
} else {
this._useCRLF = false;
}
model.fromString(content);
if (initializeModel) {
model.initialize();
}
}
this._updateContentsModel(contents);
model.dirty = dirty;
if (!this._isPopulated) {
return this._populate();
}
})
.catch(async err => {
const localPath = this._manager.contents.localPath(this._path);
const name = PathExt.basename(localPath);
const response = await err.response.json();
if (err.message === 'Invalid response: 400 bad format') {
err = new Error(response.message);
}
void this._handleError(err, `File Load Error for ${name}`);
throw err;
});
}
/**
* Save a file, dealing with conflicts.
*/
private _maybeSave(
options: Partial<Contents.IModel>
): Promise<Contents.IModel> {
let path = this._path;
// Make sure the file has not changed on disk.
let promise = this._manager.contents.get(path, { content: false });
return promise.then(
model => {
if (this.isDisposed) {
return Promise.reject(new Error('Disposed'));
}
// We want to check last_modified (disk) > last_modified (client)
// (our last save)
// In some cases the filesystem reports an inconsistent time,
// so we allow 0.5 seconds difference before complaining.
let modified = this.contentsModel?.last_modified;
let tClient = modified ? new Date(modified) : new Date();
let tDisk = new Date(model.last_modified);
if (modified && tDisk.getTime() - tClient.getTime() > 500) {
// 500 ms
return this._timeConflict(tClient, model, options);
}
return this._manager.contents.save(path, options);
},
err => {
if (err.response && err.response.status === 404) {
return this._manager.contents.save(path, options);
}
throw err;
}
);
}
/**
* Handle a save/load error with a dialog.
*/
private async _handleError(
err: Error | ServerConnection.ResponseError,
title: string
): Promise<void> {
// Check for a more specific error message.
let error = { message: '' };
if (err instanceof ServerConnection.ResponseError) {
const text = await err.response.text();
let body = '';
try {
body = JSON.parse(text).message;
} catch (e) {
body = text;
}
error.message = body || err.message;
} else {
error.message = err.message;
}
await showErrorMessage(title, error);
return;
}
/**
* Add a checkpoint the file is writable.
*/
private _maybeCheckpoint(force: boolean): Promise<void> {
let writable = this._contentsModel && this._contentsModel.writable;
let promise = Promise.resolve(void 0);
if (!writable) {
return promise;
}
if (force) {
promise = this.createCheckpoint().then(/* no-op */);
} else {
promise = this.listCheckpoints().then(checkpoints => {
writable = this._contentsModel && this._contentsModel.writable;
if (!this.isDisposed && !checkpoints.length && writable) {
return this.createCheckpoint().then(/* no-op */);
}
});
}
return promise.catch(err => {
// Handle a read-only folder.
if (!err.response || err.response.status !== 403) {
throw err;
}
});
}
/**
* Handle a time conflict.
*/
private _timeConflict(
tClient: Date,
model: Contents.IModel,
options: Partial<Contents.IModel>
): Promise<Contents.IModel> {
let tDisk = new Date(model.last_modified);
console.warn(
`Last saving performed ${tClient} ` +
`while the current file seems to have been saved ` +
`${tDisk}`
);
let body =
`"${this.path}" has changed on disk since the last time it ` +
`was opened or saved. ` +
`Do you want to overwrite the file on disk with the version ` +
` open here, or load the version on disk (revert)?`;
let revertBtn = Dialog.okButton({ label: 'Revert' });
let overwriteBtn = Dialog.warnButton({ label: 'Overwrite' });
return showDialog({
title: 'File Changed',
body,
buttons: [Dialog.cancelButton(), revertBtn, overwriteBtn]
}).then(result => {
if (this.isDisposed) {
return Promise.reject(new Error('Disposed'));
}
if (result.button.label === 'Overwrite') {
return this._manager.contents.save(this._path, options);
}
if (result.button.label === 'Revert') {
return this.revert().then(() => {
return model;
});
}
return Promise.reject(new Error('Cancel')); // Otherwise cancel the save.
});
}
/**
* Handle a time conflict.
*/
private _maybeOverWrite(path: string): Promise<void> {
let body = `"${path}" already exists. Do you want to replace it?`;
let overwriteBtn = Dialog.warnButton({ label: 'Overwrite' });
return showDialog({
title: 'File Overwrite?',
body,
buttons: [Dialog.cancelButton(), overwriteBtn]
}).then(result => {
if (this.isDisposed) {
return Promise.reject(new Error('Disposed'));
}
if (result.button.label === 'Overwrite') {
return this._manager.contents.delete(path).then(() => {
return this._finishSaveAs(path);
});
}
});
}
/**
* Finish a saveAs operation given a new path.
*/
private async _finishSaveAs(newPath: string): Promise<void> {
this._path = newPath;
return this.sessionContext.session
?.setPath(newPath)
.then(() => {
void this.sessionContext.session?.setName(newPath.split('/').pop()!);
return this.save();
})
.then(() => {
this._pathChanged.emit(this._path);
return this._maybeCheckpoint(true);
});
}
private _manager: ServiceManager.IManager;
private _opener: (
widget: Widget,
options?: DocumentRegistry.IOpenOptions
) => void;
private _model: T;
private _modelDB: IModelDB;
private _path = '';
private _useCRLF = false;
private _factory: DocumentRegistry.IModelFactory<T>;
private _contentsModel: Contents.IModel | null = null;
private _readyPromise: Promise<void>;
private _populatedPromise = new PromiseDelegate<void>();
private _isPopulated = false;
private _isReady = false;
private _isDisposed = false;
private _pathChanged = new Signal<this, string>(this);
private _fileChanged = new Signal<this, Contents.IModel>(this);
private _saveState = new Signal<this, DocumentRegistry.SaveState>(this);
private _disposed = new Signal<this, void>(this);
}
/**
* A namespace for `Context` statics.
*/
export namespace Context {
/**
* The options used to initialize a context.
*/
export interface IOptions<T extends DocumentRegistry.IModel> {
/**
* A service manager instance.
*/
manager: ServiceManager.IManager;
/**
* The model factory used to create the model.
*/
factory: DocumentRegistry.IModelFactory<T>;
/**
* The initial path of the file.
*/
path: string;
/**
* The kernel preference associated with the context.
*/
kernelPreference?: ISessionContext.IKernelPreference;
/**
* An IModelDB factory method which may be used for the document.
*/
modelDBFactory?: ModelDB.IFactory;
/**
* An optional callback for opening sibling widgets.
*/
opener?: (widget: Widget) => void;
/**
* A function to call when the kernel is busy.
*/
setBusy?: () => IDisposable;
}
}
/**
* A namespace for private data.
*/
namespace Private {
/**
* Get a new file path from the user.
*/
export function getSavePath(path: string): Promise<string | undefined> {
let saveBtn = Dialog.okButton({ label: 'Save' });
return showDialog({
title: 'Save File As..',
body: new SaveWidget(path),
buttons: [Dialog.cancelButton(), saveBtn]
}).then(result => {
if (result.button.label === 'Save') {
return result.value ?? undefined;
}
return;
});
}
/**
* A no-op function.
*/
export function noOp() {
/* no-op */
}
/*
* A widget that gets a file path from a user.
*/
class SaveWidget extends Widget {
/**
* Construct a new save widget.
*/
constructor(path: string) {
super({ node: createSaveNode(path) });
}
/**
* Get the value for the widget.
*/
getValue(): string {
return (this.node as HTMLInputElement).value;
}
}
/**
* Create the node for a save widget.
*/
function createSaveNode(path: string): HTMLElement {
let input = document.createElement('input');
input.value = path;
return input;
}
}