chore: update readme

instrumentation/github.com/astaxie/beego/README.md

@@ -35,3 +35,48 @@ You can customize instrumentation by passing any of the following options to `Ne
 | `WithPropagators(propagation.Propagators)` | The propagators to be used. If not specified, `global.Propagators()` will be used. |
 | `WithFilter(Filter)` | Adds an additional filter function to the configuration. Defaults to no filters. |
 | `WithSpanNameFormatter(SpanNameFormatter)` | The formatter used to format span names. If not specified, the route will be used instead. |
+
+You can also trace the `Render`, `RenderString`, and `RenderBytes` functions. You should disable the `AutoRender` setting either programmatically or in the config file, so you can explicitly call the traced implementations:
+
+```go
+package main
+
+import (
+        "github.com/astaxie/beego"
+
+        otelBeego "go.opentelemetry.io/contrib/instrumentation/github.com/astaxie/beego"
+)
+
+type ExampleController struct {
+        beego.Controller
+}
+
+func (c *ExampleController) Get() {
+        c.TplName = "index.ptl"
+
+        // explicit call to traced Render function
+        otelBeego.Render(&c.Controller)
+}
+
+func main() {
+        // Init the tracer and metric export pipelines
+
+        // Disable autorender
+        beego.BConfig.WebConfig.AutoRender = false
+
+        // Create your routes
+        beego.Router("/", &ExampleController{})
+
+        // Create the MiddleWare
+        mware := otelBeego.NewOTelBeegoMiddleWare("example-server")
+
+        // Run the server with the MiddleWare
+        beego.RunWithMiddleWares("localhost:8080", mware)
+}
+```
+
+| Function | Description |
+| -------- | ----------- |
+| `Render(*beego.Controller) error` | Provides tracing to `beego.Render`. |
+| `RenderString(*beego.Controller) (string, error)` | Provides tracing to `beego.RenderString`. |
+| `RenderBytes(*beego.Controller) ([]byte, error)` | Provides tracing to `beego.RenderBytes`. |