vscode插件快餐教程(7) - 从头开始写一个完整的lsp工程

有了一定的基础知识之后，我们就可以开始搭建一个client和server模式的lsp的插件了。

server目录

首先我们来写server端的代码。

package.json

首先我们来写package.json. 因为微软的sdk已经帮我们封装好了大部分细节，其实我们只要引用vscode-languageserver的模块就可以了：

{
    "name": "lsp-demo-server",
    "description": "demo language server",
    "version": "1.0.0",
    "author": "Xulun",
    "license": "MIT",
    "engines": {
        "node": "*"
    },
    "repository": {
        "type": "git",
        "url": "git@code.aliyun.com:lusinga/testlsp.git"
    },
    "dependencies": {
        "vscode-languageserver": "^4.1.3"
    },
    "scripts": {}
}

有了package.json之后，我们就可以在server目录下运行npm install命令将依赖安装进来。
安装之后会有下面的模块被引用进来：

• vscode-jsonrpc
• vscode-languageserver
• vscode-languageserver-protocol
• vscode-languageserver-types vscode-uri

tsconfig.json

因为我们是要用typescript来写server，所以我们用tsconfig.json来配置Typescript的选项：

{
    "compilerOptions": {
        "target": "es6",
        "module": "commonjs",
        "moduleResolution": "node",
        "sourceMap": true,
        "outDir": "out",
        "rootDir": "src",
        "lib": ["es6"]
    },
    "include": ["src"],
    "exclude": ["node_modules", ".vscode-test"]
}

server.ts

下面我们开始写服务端的ts文件，首先我们要把vscode-languageserver和vscode-jsonrpc的依赖引入进来：

import {
    createConnection,
    TextDocuments,
    TextDocument,
    Diagnostic,
    DiagnosticSeverity,
    ProposedFeatures,
    InitializeParams,
    DidChangeConfigurationNotification,
    CompletionItem,
    CompletionItemKind,
    TextDocumentPositionParams,
    SymbolInformation,
    WorkspaceSymbolParams,
    WorkspaceEdit,
    WorkspaceFolder
} from 'vscode-languageserver';
import { HandlerResult } from 'vscode-jsonrpc';

下面，为了打印日志方便，我们使用log4js来打印日志，通过npm i log4js --save将其模块引入进来，然后对其进行初始化：

import { configure, getLogger } from "log4js";
configure({
    appenders: {
        lsp_demo: {
            type: "dateFile",
            filename: "/Users/ziyingliuziying/working/lsp_demo",
            pattern: "yyyy-MM-dd-hh.log",
            alwaysIncludePattern: true,
        },
    },
    categories: { default: { appenders: ["lsp_demo"], level: "debug" } }
});
const logger = getLogger("lsp_demo");

然后我们就可以调用createConnection来创建连接了：

let connection = createConnection(ProposedFeatures.all);

接着我们就可以处理一个个的事件啦，比如处理第6节介绍的初始化事件：

connection.onInitialize((params: InitializeParams) => {
    let capabilities = params.capabilities;

    return {
        capabilities: {
            completionProvider: {
                resolveProvider: true
            }
        }
    };
});

三次握手之后，我们可以在vscode上显示一条消息：

connection.onInitialized(() => {
    connection.window.showInformationMessage('Hello World! form server side');
});

最后，我们可以把第5节学过的代码补全的部分给加上：

connection.onCompletion(
    (_textDocumentPosition: TextDocumentPositionParams): CompletionItem[] => {

        return [
            {
                label: 'TextView' + _textDocumentPosition.position.character,
                kind: CompletionItemKind.Text,
                data: 1
            },
            {
                label: 'Button' + _textDocumentPosition.position.line,
                kind: CompletionItemKind.Text,
                data: 2
            },
            {
                label: 'ListView',
                kind: CompletionItemKind.Text,
                data: 3
            }
        ];
    }
);

connection.onCompletionResolve(
    (item: CompletionItem): CompletionItem => {
        if (item.data === 1) {
            item.detail = 'TextView';
            item.documentation = 'TextView documentation';
        } else if (item.data === 2) {
            item.detail = 'Button';
            item.documentation = 'JavaScript documentation';
        } else if (item.data === 3) {
            item.detail = 'ListView';
            item.documentation = 'ListView documentation';
        }
        return item;
    }
);

client目录

服务端这就算开发就绪了，下面我们来开发客户端。

package.json

首先还是先写package.json，依赖于vscode-languageclient，不要跟服务端用的库vscode-languageserver搞混了哈。

{
    "name": "lspdemo-client",
    "description": "demo language server client",
    "author": "Xulun",
    "license": "MIT",
    "version": "0.0.1",
    "publisher": "Xulun",
    "repository": {
        "type": "git",
        "url": "git@code.aliyun.com:lusinga/testlsp.git"
    },
    "engines": {
        "vscode": "^1.33.1"
    },
    "scripts": {
        "update-vscode": "vscode-install",
        "postinstall": "vscode-install"
    },
    "dependencies": {
        "path": "^0.12.7",
        "vscode-languageclient": "^4.1.4"
    },
    "devDependencies": {
        "vscode": "^1.1.30"
    }
}

tsconfig.json

反正都是ts，客户端与服务端比也没有增加啥特别的，于是照抄一份：

{
    "compilerOptions": {
        "module": "commonjs",
        "target": "es6",
        "outDir": "out",
        "rootDir": "src",
        "lib": ["es6"],
        "sourceMap": true
    },
    "include": ["src"],
    "exclude": ["node_modules", ".vscode-test"]
}

extension.ts

下面我们来写extension.ts。

其实客户端要做的事情比server还少，本质上就是启动server就好：

    // Create the language client and start the client.
    client = new LanguageClient(
        'DemoLanguageServer',
        'Demo Language Server',
        serverOptions,
        clientOptions
    );

    // Start the client. This will also launch the server
    client.start();

serverOptions用来配置服务端的参数，其定义为：

export type ServerOptions = 
Executable | 
{ run: Executable; debug: Executable; } | 
{ run: NodeModule; debug: NodeModule } | 
NodeModule | 
(() => Thenable<ChildProcess | StreamInfo | MessageTransports | ChildProcessInfo>);

相关类型的简图如下：

ServerOptions.png

下面我们来配置一下：

    // 服务端配置
    let serverModule = context.asAbsolutePath(
        path.join('server', 'out', 'server.js')
    );

    let serverOptions: ServerOptions = {
        module: serverModule, transport: TransportKind.ipc
    };

    // 客户端配置
    let clientOptions: LanguageClientOptions = {
        // js代码触发事情
        documentSelector: [{ scheme: 'file', language: 'js' }],
    };

extension.ts的完整代码如下：

import * as path from 'path';
import { workspace, ExtensionContext } from 'vscode';

import {
    LanguageClient,
    LanguageClientOptions,
    ServerOptions,
    TransportKind
} from 'vscode-languageclient';

let client: LanguageClient;

export function activate(context: ExtensionContext) {
    // 服务端配置
    let serverModule = context.asAbsolutePath(
        path.join('server', 'out', 'server.js')
    );

    let serverOptions: ServerOptions = {
        module: serverModule, transport: TransportKind.ipc
    };

    // 客户端配置
    let clientOptions: LanguageClientOptions = {
        // js代码触发事情
        documentSelector: [{ scheme: 'file', language: 'js' }],
    };

    client = new LanguageClient(
        'DemoLanguageServer',
        'Demo Language Server',
        serverOptions,
        clientOptions
    );

    // 启动客户端，同时启动语言服务器
    client.start();
}

export function deactivate(): Thenable<void> | undefined {
    if (!client) {
        return undefined;
    }
    return client.stop();
}

组装运行

万事俱备，只欠包装，下面我们将上面的客户端和服务器组装一下。

插件配置 - package.json

我们关注点主要是入口函数和触发事件：

    "activationEvents": [
        "onLanguage:javascript"
    ],
    "main": "./client/out/extension",

完整的package.json如下：

{
    "name": "lsp_demo_server",
    "description": "A demo language server",
    "author": "Xulun",
    "license": "MIT",
    "version": "1.0.0",
    "repository": {
        "type": "git",
        "url": "git@code.aliyun.com:lusinga/testlsp.git"
    },
    "publisher": "Xulun",
    "categories": [],
    "keywords": [],
    "engines": {
        "vscode": "^1.33.1"
    },
    "activationEvents": [
        "onLanguage:javascript"
    ],
    "main": "./client/out/extension",
    "contributes": {},
    "scripts": {
        "vscode:prepublish": "cd client && npm run update-vscode && cd .. && npm run compile",
        "compile": "tsc -b",
        "watch": "tsc -b -w",
        "postinstall": "cd client && npm install && cd ../server && npm install && cd ..",
        "test": "sh ./scripts/e2e.sh"
    },
    "devDependencies": {
        "@types/mocha": "^5.2.0",
        "@types/node": "^8.0.0",
        "tslint": "^5.11.0",
        "typescript": "^3.1.3"
    }
}

装配tsconfig.json

我们还需要一个总的tsconfig.json，引用client和server两个目录：

{
    "compilerOptions": {
        "module": "commonjs",
        "target": "es6",
        "outDir": "out",
        "rootDir": "src",
        "lib": [ "es6" ],
        "sourceMap": true
    },
    "include": [
        "src"
    ],
    "exclude": [
        "node_modules",
        ".vscode-test"
    ],
    "references": [
        { "path": "./client" },
        { "path": "./server" }
    ]
}

配置vscode

上面，我们就将client, server和整合它们的代码全部写完了。
下面我们在.vscode目录中写两个配置文件，使我们可以更方便地调试和运行。

.vscode/launch.json

有了这个文件之后，我们就有了运行的配置，可以通过F5来启动。

// A launch configuration that compiles the extension and then opens it inside a new window
{
    "version": "0.2.0",
    "configurations": [
        {
            "type": "extensionHost",
            "request": "launch",
            "name": "Launch Client",
            "runtimeExecutable": "${execPath}",
            "args": ["--extensionDevelopmentPath=${workspaceRoot}"],
            "outFiles": ["${workspaceRoot}/client/out/**/*.js"],
            "preLaunchTask": {
                "type": "npm",
                "script": "watch"
            }
        },
        {
            "type": "node",
            "request": "attach",
            "name": "Attach to Server",
            "port": 6009,
            "restart": true,
            "outFiles": ["${workspaceRoot}/server/out/**/*.js"]
        },
    ],
    "compounds": [
        {
            "name": "Client + Server",
            "configurations": ["Launch Client", "Attach to Server"]
        }
    ]
}

.vscode/tasks.json

配置npm compile和npm watch两个脚本。

{
    "version": "2.0.0",
    "tasks": [
        {
            "type": "npm",
            "script": "compile",
            "group": "build",
            "presentation": {
                "panel": "dedicated",
                "reveal": "never"
            },
            "problemMatcher": [
                "$tsc"
            ]
        },
        {
            "type": "npm",
            "script": "watch",
            "isBackground": true,
            "group": {
                "kind": "build",
                "isDefault": true
            },
            "presentation": {
                "panel": "dedicated",
                "reveal": "never"
            },
            "problemMatcher": [
                "$tsc-watch"
            ]
        }
    ]
}

一切就绪之后，在插件根目录下运行下npm install。
然后在vscode中运行build命令，比如mac下是cmd-shift-b，于是就构建生成了server和client的out目录下的js和map。
现在就可以通过F5键运行啦。

本示例的源代码放在code.aliyun.com:lusinga/testlsp.git中。