Step by Step Guide to Building a Looker API Integration in C#

Introduction

Hey there, fellow developer! Ready to dive into the world of Looker API integration? You're in for a treat. Looker's API is a powerhouse that'll let you programmatically access and manipulate your data like a boss. In this guide, we'll walk through building a solid integration in C#. Let's get cracking!

Prerequisites

Before we jump in, make sure you've got:

• Looker API credentials (client ID and secret)
• Your favorite C# development environment
• A burning desire to make data bend to your will

Setting up the project

First things first, let's get our project off the ground:

1. Fire up your IDE and create a new C# project.
2. Install the necessary NuGet packages:

Install-Package Newtonsoft.Json
Install-Package RestSharp

Authentication

Alright, let's tackle authentication. Looker uses OAuth 2.0, so we'll need to get our hands on an access token:

using RestSharp;
using Newtonsoft.Json.Linq;

public class LookerClient
{
    private string _accessToken;
    private readonly string _baseUrl;
    private readonly string _clientId;
    private readonly string _clientSecret;

    public LookerClient(string baseUrl, string clientId, string clientSecret)
    {
        _baseUrl = baseUrl;
        _clientId = clientId;
        _clientSecret = clientSecret;
    }

    private async Task AuthenticateAsync()
    {
        var client = new RestClient($"{_baseUrl}/api/3.1/login");
        var request = new RestRequest(Method.POST);
        request.AddHeader("Content-Type", "application/x-www-form-urlencoded");
        request.AddParameter("client_id", _clientId);
        request.AddParameter("client_secret", _clientSecret);

        var response = await client.ExecuteAsync(request);
        var jsonResponse = JObject.Parse(response.Content);
        _accessToken = jsonResponse["access_token"].ToString();
    }
}

Making API requests

Now that we're authenticated, let's make our first API call:

public async Task<string> GetLookAsync(int lookId)
{
    if (string.IsNullOrEmpty(_accessToken))
        await AuthenticateAsync();

    var client = new RestClient($"{_baseUrl}/api/3.1/looks/{lookId}");
    var request = new RestRequest(Method.GET);
    request.AddHeader("Authorization", $"Bearer {_accessToken}");

    var response = await client.ExecuteAsync(request);
    return response.Content;
}

Common API operations

Let's add a few more methods to our LookerClient class:

public async Task<string> RunQueryAsync(int queryId)
{
    // Implementation similar to GetLookAsync
}

public async Task<string> GetDashboardAsync(int dashboardId)
{
    // Implementation similar to GetLookAsync
}

Error handling and best practices

Don't forget to implement proper error handling and respect rate limits:

private async Task<IRestResponse> ExecuteWithRetryAsync(RestRequest request, int maxRetries = 3)
{
    for (int i = 0; i < maxRetries; i++)
    {
        var response = await _client.ExecuteAsync(request);
        if (response.StatusCode != HttpStatusCode.TooManyRequests)
            return response;

        await Task.Delay(1000 * (i + 1)); // Exponential backoff
    }
    throw new Exception("Max retries exceeded");
}

Advanced topics

Want to level up? Consider implementing:

• Pagination for large result sets
• Streaming for hefty data downloads
• Caching to reduce API calls and improve performance

Testing the integration

Don't forget to test your integration thoroughly:

[TestMethod]
public async Task TestGetLook()
{
    var client = new LookerClient("https://your-instance.looker.com", "your-client-id", "your-client-secret");
    var result = await client.GetLookAsync(1);
    Assert.IsNotNull(result);
}

Conclusion

And there you have it! You've just built a robust Looker API integration in C#. Remember, this is just the tip of the iceberg. The Looker API has tons more to offer, so don't be afraid to explore and experiment.

Keep coding, keep learning, and most importantly, keep having fun with data!