SQL Operations Studio Public Preview 1 (0.23) release source code

extensions/git/src/contentProvider.ts

@@ -0,0 +1,117 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+'use strict';
+
+import { workspace, Uri, Disposable, Event, EventEmitter, window } from 'vscode';
+import { debounce } from './decorators';
+import { fromGitUri } from './uri';
+import { Model, ModelChangeEvent } from './model';
+
+interface CacheRow {
+	uri: Uri;
+	timestamp: number;
+}
+
+interface Cache {
+	[uri: string]: CacheRow;
+}
+
+const THREE_MINUTES = 1000 * 60 * 3;
+const FIVE_MINUTES = 1000 * 60 * 5;
+
+export class GitContentProvider {
+
+	private onDidChangeEmitter = new EventEmitter<Uri>();
+	get onDidChange(): Event<Uri> { return this.onDidChangeEmitter.event; }
+
+	private changedRepositoryRoots = new Set<string>();
+	private cache: Cache = Object.create(null);
+	private disposables: Disposable[] = [];
+
+	constructor(private model: Model) {
+		this.disposables.push(
+			model.onDidChangeRepository(this.onDidChangeRepository, this),
+			workspace.registerTextDocumentContentProvider('git', this)
+		);
+
+		setInterval(() => this.cleanup(), FIVE_MINUTES);
+	}
+
+	private onDidChangeRepository({ repository }: ModelChangeEvent): void {
+		this.changedRepositoryRoots.add(repository.root);
+		this.eventuallyFireChangeEvents();
+	}
+
+	@debounce(1100)
+	private eventuallyFireChangeEvents(): void {
+		this.fireChangeEvents();
+	}
+
+	private fireChangeEvents(): void {
+		Object.keys(this.cache).forEach(key => {
+			const uri = this.cache[key].uri;
+			const fsPath = uri.fsPath;
+
+			for (const root of this.changedRepositoryRoots) {
+				if (fsPath.startsWith(root)) {
+					this.onDidChangeEmitter.fire(uri);
+					return;
+				}
+			}
+		});
+
+		this.changedRepositoryRoots.clear();
+	}
+
+	async provideTextDocumentContent(uri: Uri): Promise<string> {
+		const repository = this.model.getRepository(uri);
+
+		if (!repository) {
+			return '';
+		}
+
+		const cacheKey = uri.toString();
+		const timestamp = new Date().getTime();
+		const cacheValue = { uri, timestamp };
+
+		this.cache[cacheKey] = cacheValue;
+
+		let { path, ref } = fromGitUri(uri);
+
+		if (ref === '~') {
+			const fileUri = Uri.file(path);
+			const uriString = fileUri.toString();
+			const [indexStatus] = repository.indexGroup.resourceStates.filter(r => r.original.toString() === uriString);
+			ref = indexStatus ? '' : 'HEAD';
+		}
+
+		try {
+			return await repository.show(ref, path);
+		} catch (err) {
+			return '';
+		}
+	}
+
+	private cleanup(): void {
+		const now = new Date().getTime();
+		const cache = Object.create(null);
+
+		Object.keys(this.cache).forEach(key => {
+			const row = this.cache[key];
+			const isOpen = window.visibleTextEditors.some(e => e.document.uri.fsPath === row.uri.fsPath);
+
+			if (isOpen || now - row.timestamp < THREE_MINUTES) {
+				cache[row.uri.toString()] = row;
+			}
+		});
+
+		this.cache = cache;
+	}
+
+	dispose(): void {
+		this.disposables.forEach(d => d.dispose());
+	}
+}