implement Copilot based on the proposed languageModels API (#1310)

* upgrade vscode engine to use log OutputChannel

* use `languageModels` API proposal.

* implement `Copilot` based on the proposed languageModels api and handles incomplement responses.

* fix adding property to telemetry event and rename output channel.

Author: wangmingliang-ms

package-lock.json

@@ -7,7 +7,7 @@
   "publisher": "vscjava",
   "preview": false,
   "engines": {
-    "vscode": "^1.64.0"
+    "vscode": "^1.74.0"
   },
   "aiKey": "b4a8a622-6ac7-4cf8-83aa-f325e1890795",
   "icon": "logo.png",
@@ -38,6 +38,9 @@
   "capabilities": {
     "virtualWorkspaces": false
   },
+  "enabledApiProposals": [
+    "languageModels"
+  ],
   "activationEvents": [
     "onLanguage:java",
     "workspaceContains:pom.xml",
@@ -333,7 +336,7 @@
     "@types/react-dom": "^16.9.16",
     "@types/react-redux": "^7.1.24",
     "@types/semver": "^7.3.12",
-    "@types/vscode": "1.64.0",
+    "@types/vscode": "^1.74.0",
     "@types/winreg": "^1.2.31",
     "@types/xmldom": "^0.1.31",
     "autoprefixer": "^10.4.12",

package.json

@@ -0,0 +1,66 @@
+import { LanguageModelChatMessage, LanguageModelChatUserMessage, LanguageModelChatAssistantMessage, lm, Disposable, CancellationToken, LanguageModelChatRequestOptions } from "vscode";
+import { instrumentSimpleOperation, sendInfo } from "vscode-extension-telemetry-wrapper";
+import { logger } from "./utils";
+
+export default class Copilot {
+    public static readonly DEFAULT_END_MARK = '<|endofresponse|>';
+    public static readonly DEFAULT_MAX_ROUNDS = 10;
+    public static readonly DEFAULT_MODEL = 'copilot-gpt-4';
+    public static readonly DEFAULT_MODEL_OPTIONS: LanguageModelChatRequestOptions = { modelOptions: {} };
+    public static readonly NOT_CANCELLABEL: CancellationToken = { isCancellationRequested: false, onCancellationRequested: () => Disposable.from() };
+
+    public constructor(
+        private readonly systemMessagesOrSamples: LanguageModelChatMessage[],
+        private readonly model: string = Copilot.DEFAULT_MODEL,
+        private readonly modelOptions: LanguageModelChatRequestOptions = Copilot.DEFAULT_MODEL_OPTIONS,
+        private readonly maxRounds: number = Copilot.DEFAULT_MAX_ROUNDS,
+        private readonly endMark: string = Copilot.DEFAULT_END_MARK
+    ) {
+    }
+
+    private async doSend(
+        userMessage: string,
+        modelOptions: LanguageModelChatRequestOptions = Copilot.DEFAULT_MODEL_OPTIONS,
+        cancellationToken: CancellationToken = Copilot.NOT_CANCELLABEL
+    ): Promise<string> {
+        let answer: string = '';
+        let rounds: number = 0;
+        const messages = [...this.systemMessagesOrSamples];
+        const _send = async (message: string): Promise<boolean> => {
+            rounds++;
+            logger.info(`User: \n`, message);
+            messages.push(new LanguageModelChatUserMessage(message));
+            logger.info('Copilot: thinking...');
+
+            let rawAnswer: string = '';
+            try {
+                const response = await lm.sendChatRequest(this.model, messages, modelOptions ?? this.modelOptions, cancellationToken);
+                for await (const item of response.stream) {
+                    rawAnswer += item;
+                }
+            } catch (e) {
+                logger.error(`Failed to send request to copilot`, e);
+                throw new Error(`Failed to send request to copilot: ${e}`);
+            }
+            messages.push(new LanguageModelChatAssistantMessage(rawAnswer));
+            logger.info(`Copilot: \n`, rawAnswer);
+            answer += rawAnswer;
+            return answer.trim().endsWith(this.endMark);
+        };
+        let complete: boolean = await _send(userMessage);
+        while (!complete && rounds < this.maxRounds) {
+            complete = await _send('continue where you left off.');
+        }
+        logger.debug('rounds', rounds);
+        sendInfo('java.copilot.sendRequest.rounds', { rounds: rounds });
+        return answer.replace(this.endMark, "");
+    }
+
+    public async send(
+        userMessage: string,
+        modelOptions: LanguageModelChatRequestOptions = Copilot.DEFAULT_MODEL_OPTIONS,
+        cancellationToken: CancellationToken = Copilot.NOT_CANCELLABEL
+    ): Promise<string> {
+        return instrumentSimpleOperation("java.copilot.sendRequest", this.doSend.bind(this))(userMessage, modelOptions, cancellationToken);
+    }
+}

src/copilot/Copilot.ts

@@ -0,0 +1,3 @@
+import { LogOutputChannel, window } from "vscode";
+
+export const logger: LogOutputChannel = window.createOutputChannel("Java Rewriting Suggestions", { log: true });