Update README.md

Author: shibayan

README.md

@@ -1,2 +1,98 @@
-# azure-functions-http-api
- 
+# HTTP API Extensions for Azure Functions v3
+
+[![Build Status](https://dev.azure.com/shibayan/azure-functions-http-api/_apis/build/status/Build%20azure-functions-http-api?branchName=master)](https://dev.azure.com/shibayan/azure-functions-http-api/_build/latest?definitionId=57&branchName=master)
+[![License](https://img.shields.io/github/license/shibayan/azure-functions-http-api.svg)](https://github.com/shibayan/azure-functions-http-api/blob/master/LICENSE)
+
+## NuGet Packages
+
+Package Name | Target Framework | NuGet
+---|---|---
+WebJobs.Extensions.HttpApi | .NET Core 3.1 | [![NuGet](https://img.shields.io/nuget/v/WebJobs.Extensions.HttpApi.svg)](https://www.nuget.org/packages/WebJobs.Extensions.HttpApi)
+
+## Basic usage
+
+### Model validation
+
+```csharp
+public class Function1 : HttpFunctionBase
+{
+    public Function1(IHttpContextAccessor httpContextAccessor)
+        : base(httpContextAccessor)
+    {
+    }
+
+    [FunctionName("Function1")]
+    public IActionResult Run(
+        [HttpTrigger(AuthorizationLevel.Function, "post")]
+        SampleModel model,
+        ILogger log)
+    {
+        if (!TryValidateModel(model))
+        {
+            return BadRequest(ModelState);
+        }
+
+        return Ok(model);
+    }
+}
+
+public class SampleModel
+{
+    [Required]
+    public string Name { get; set; }
+
+    public string[] Array { get; set; }
+
+    [Range(100, 10000)]
+    public int Price { get; set; }
+}
+```
+
+### ASP.NET Core like properties
+
+```csharp
+public class Function2 : HttpFunctionBase
+{
+    public Function2(IHttpContextAccessor httpContextAccessor)
+        : base(httpContextAccessor)
+    {
+    }
+
+    [FunctionName("Function2")]
+    public IActionResult Run(
+        [HttpTrigger(AuthorizationLevel.Function, "get")]
+        HttpRequest req,
+        ILogger log)
+    {
+        Response.Headers.Add("Cache-Control", "no-cache");
+
+        return Ok($"Now: {DateTime.Now}");
+    }
+}
+```
+
+### Support URL generation
+
+```csharp
+public class Function3 : HttpFunctionBase
+{
+    public Function3(IHttpContextAccessor httpContextAccessor)
+        : base(httpContextAccessor)
+    {
+    }
+
+    [FunctionName("Function3")]
+    public IActionResult Run(
+        [HttpTrigger(AuthorizationLevel.Function, "get", Route = "route/{id}")]
+        HttpRequest req,
+        string id,
+        ILogger log)
+    {
+        return CreatedAtFunction("Function3", new { id = "kazuakix" }, null);
+    }
+}
+```
+
+## License
+
+This project is licensed under the [MIT License](https://github.com/shibayan/azure-functions-http-api/blob/master/LICENSE)