Add custom HTML content views

This change adds new custom HTML content views which are driven by the
new HtmlContentView APIs in the PowerShellEditorServices.VSCode module.
These views allow the user to show a custom view with rendered HTML
content that can either be set or appended to using PowerShell cmdlets.

Resolves PowerShell#191

src/features/CustomViews.ts

@@ -0,0 +1,243 @@
+/*---------------------------------------------------------
+ * Copyright (C) Microsoft Corporation. All rights reserved.
+ *--------------------------------------------------------*/
+
+import vscode = require('vscode');
+import { IFeature } from '../feature';
+import { LanguageClient, RequestType, NotificationType } from 'vscode-languageclient';
+
+export class CustomViewsFeature implements IFeature {
+
+    private commands: vscode.Disposable[] = [];
+    private languageClient: LanguageClient;
+    private contentProvider: PowerShellContentProvider;
+
+    constructor() {
+        this.contentProvider = new PowerShellContentProvider();
+        this.commands.push(
+            vscode.workspace.registerTextDocumentContentProvider(
+                "powershell",
+                this.contentProvider));
+    }
+
+    public setLanguageClient(languageClient: LanguageClient) {
+
+        languageClient.onRequest(
+            NewCustomViewRequest.type,
+            args => {
+                this.contentProvider.createView(
+                    args.id,
+                    args.title,
+                    args.viewType);
+            });
+
+        languageClient.onRequest(
+            ShowCustomViewRequest.type,
+            args => {
+                this.contentProvider.showView(
+                    args.id,
+                    args.viewColumn);
+            });
+
+        languageClient.onRequest(
+            CloseCustomViewRequest.type,
+            args => {
+                this.contentProvider.closeView(args.id);
+            });
+
+        languageClient.onRequest(
+            SetHtmlContentViewRequest.type,
+            args => {
+                this.contentProvider.setHtmlContentView(
+                    args.id,
+                    args.htmlBodyContent);
+            });
+
+        languageClient.onRequest(
+            AppendHtmlOutputViewRequest.type,
+            args => {
+                this.contentProvider.appendHtmlOutputView(
+                    args.id,
+                    args.appendedHtmlBodyContent);
+            });
+
+        this.languageClient = languageClient;
+    }
+
+    public dispose() {
+        this.commands.forEach(d => d.dispose());
+    }
+}
+
+class PowerShellContentProvider implements vscode.TextDocumentContentProvider {
+
+    private count: number = 1;
+    private viewIndex: { [id: string]: CustomView } = {};
+    private didChangeEvent: vscode.EventEmitter<vscode.Uri> = new vscode.EventEmitter<vscode.Uri>();
+
+    public provideTextDocumentContent(uri: vscode.Uri): string {
+        return this.viewIndex[uri.toString()].getContent();
+    }
+
+    public createView(id: string, title: string, viewType: CustomViewType) {
+        let view = undefined;
+        switch (viewType) {
+            case CustomViewType.HtmlContent:
+                view = new HtmlContentView(id, title);
+        };
+
+        this.viewIndex[this.getUri(view.id)] = view;
+    }
+
+    public showView(id: string, viewColumn: vscode.ViewColumn) {
+        let uriString = this.getUri(id);
+        let view: CustomView = this.viewIndex[uriString];
+
+        vscode.commands.executeCommand(
+            "vscode.previewHtml",
+            uriString,
+            viewColumn,
+            view.title);
+    }
+
+    public closeView(id: string) {
+        let uriString = this.getUri(id);
+        let view: CustomView = this.viewIndex[uriString];
+
+        vscode.workspace.textDocuments.some(
+            doc => {
+                if (doc.uri.toString() === uriString) {
+                    vscode.window
+                        .showTextDocument(doc)
+                        .then(editor => vscode.commands.executeCommand("workbench.action.closeActiveEditor"))
+
+                    return true;
+                }
+
+                return false;
+            }
+        )
+    }
+
+    public setHtmlContentView(id: string, content: string) {
+        let uriString = this.getUri(id);
+        let view: CustomView = this.viewIndex[uriString];
+
+        if (view.viewType === CustomViewType.HtmlContent) {
+            (<HtmlContentView>view).setContent(content);
+            this.didChangeEvent.fire(vscode.Uri.parse(uriString));
+        }
+    }
+
+    public appendHtmlOutputView(id: string, content: string) {
+        let uriString = this.getUri(id);
+        let view: CustomView = this.viewIndex[uriString];
+
+        if (view.viewType === CustomViewType.HtmlContent) {
+            (<HtmlContentView>view).appendContent(content);
+            this.didChangeEvent.fire(vscode.Uri.parse(uriString));
+        }
+    }
+
+    private getUri(id: string) {
+        return `powershell://views/${id}`;
+    }
+
+    public onDidChange: vscode.Event<vscode.Uri> = this.didChangeEvent.event;
+}
+
+abstract class CustomView {
+
+    constructor(
+        public id: string,
+        public title: string,
+        public viewType: CustomViewType)
+    {
+    }
+
+    abstract getContent(): string;
+}
+
+class HtmlContentView extends CustomView {
+
+    private htmlContent: string = "";
+
+    constructor(
+        id: string,
+        title: string)
+    {
+        super(id, title, CustomViewType.HtmlContent);
+    }
+
+    setContent(htmlContent: string) {
+        this.htmlContent = htmlContent;
+    }
+
+    appendContent(content: string) {
+        this.htmlContent += content;
+    }
+
+    getContent(): string {
+        // Return an HTML page which disables JavaScript in content by default
+        return `<html><head><meta http-equiv="Content-Security-Policy" content="default-src 'none'; img-src *; style-src 'self'; script-src 'none';"></head><body>${this.htmlContent}</body></html>`;
+    }
+}
+
+enum CustomViewType {
+    HtmlContent = 1,
+}
+
+namespace NewCustomViewRequest {
+    export const type =
+        new RequestType<NewCustomViewRequestArguments, void, void, void>(
+            'powerShell/newCustomView');
+}
+
+interface NewCustomViewRequestArguments {
+    id: string;
+    title: string;
+    viewType: CustomViewType;
+}
+
+namespace ShowCustomViewRequest {
+    export const type =
+        new RequestType<ShowCustomViewRequestArguments, void, void, void>(
+            'powerShell/showCustomView');
+}
+
+interface ShowCustomViewRequestArguments {
+    id: string;
+    viewColumn: vscode.ViewColumn;
+}
+
+namespace CloseCustomViewRequest {
+    export const type =
+        new RequestType<CloseCustomViewRequestArguments, void, void, void>(
+            'powerShell/closeCustomView');
+}
+
+interface CloseCustomViewRequestArguments {
+    id: string;
+}
+
+namespace SetHtmlContentViewRequest {
+    export const type =
+        new RequestType<SetHtmlContentViewRequestArguments, void, void, void>(
+            'powerShell/setHtmlViewContent');
+}
+
+interface SetHtmlContentViewRequestArguments {
+    id: string;
+    htmlBodyContent: string;
+}
+
+namespace AppendHtmlOutputViewRequest {
+    export const type =
+        new RequestType<AppendHtmlOutputViewRequestArguments, void, void, void>(
+            'powerShell/appendHtmlViewContent');
+}
+
+interface AppendHtmlOutputViewRequestArguments {
+    id: string;
+    appendedHtmlBodyContent: string;
+}

src/main.ts

@@ -15,6 +15,7 @@ import { PowerShellLanguageId } from './utils';
 import { ConsoleFeature } from './features/Console';
 import { ExamplesFeature } from './features/Examples';
 import { OpenInISEFeature } from './features/OpenInISE';
+import { CustomViewsFeature } from './features/CustomViews';
 import { ExpandAliasFeature } from './features/ExpandAlias';
 import { ShowHelpFeature } from './features/ShowOnlineHelp';
 import { CodeActionsFeature } from './features/CodeActions';
@@ -121,7 +122,8 @@ export function activate(context: vscode.ExtensionContext): void {
         new DebugSessionFeature(sessionManager),
         new PickPSHostProcessFeature(),
         new SpecifyScriptArgsFeature(context),
-        new HelpCompletionFeature()
+        new HelpCompletionFeature(),
+        new CustomViewsFeature()
     ];
 
     sessionManager.setExtensionFeatures(extensionFeatures);