Trying out the Dart Analysis Server

I wanted to see how the Dart Analysis Server was put together and worked. I started looking to see how I could wire it up and try out the code reporting functionality. I went to the source but found there wasn't much to go on. But then I found a super easy way to try it out, and I'll get to that shortly. 

Usage Options

There are few methods in which the Dart Analyzer can be used. The first method being the CLI where you can provide the dart analyzer with arguments. The second method being where you could directly use the analyzer source code logically in your application like the dartdoc application does. The third method being where you can run the Dart Analysis Server where the analyzer is run as a service. It's the service that I'm interested in. 

Server Package

I started by going to the source, the Analysis Server package hoping I could find an easy execution method. I also found the api reference for it. But since this tool isn't used by many, there wasn't much to go on. I could reverse engineer the ./bin/server.dart execution, but I didn't want to spend time on that yet, hoping for an easier solution. 

SDK Packages

That's when I noticed the Dart SDK packages. And low and behold, there was a packaged named analysis_server_client. And the best part, I found it had example.dart code. 

Dart Analysis Server Client

I didn't realize it yet, but when I found example.dart I struck gold. This example provides a perfect example of how to wire up the Dart Analysis Server, add subscriptions and listen to the responses.

Trying Out the Dart Analysis Server

With three easy steps, I had the client connected to the Dart Analysis Server. 

The example.dart could be run from command line but I wanted to run it from Visual Studio Code. So in this example I started the process form Visual Studio Code which allows me to break point in the process.

1. I copied the example.dart to my dart project lib directory. 
2. I added `analysis_server_client: any` to my pubsec.yaml dependencies and ran `pub get`.
3. I added a Visual Studio Code Launcher to run the example.dart process on the ./lib directory.

   
   // Visual Studio Code Launchers Configs
   // Project file: ./.vscode/launch.json
   {
     "version": "0.2.0",
     "configurations": [
       {
         "name": "Run Example Dart Analysis Server Client",
         "program": "lib/src/example/example.dart",
         "request": "launch",
         "type": "dart",
         "args": [
           "./lib"
         ]
       }
     ]
   }
   

See it in Action

With the three steps done above, I run the process listening for changing in the ./lib directory. I change the values and save them and soon after the save a report on the modifications is reported in the console output.