Contextual data

The Lightning framework provides a powerful feature called Contextual Data that allows developers to store and retrieve data within the context of a request. This feature is particularly useful for storing session data, user information, and other request-specific data.

package main

import (
    "fmt"

    "github.com/go-labx/lightning"
)

func main() {
    app := lightning.NewApp()

    // Middleware to set session data
    app.Use(func(ctx *lightning.Context) {
        ctx.SetData("session", map[string]interface{}{
            "userId":   123,
            "username": "Jack",
        })
        ctx.Next()
    })

    // Middleware to get session data
    app.Use(func(ctx *lightning.Context) {
        session := ctx.GetData("session")
        // write your logic here...
        fmt.Println(session)

        ctx.Next()
    })

    // Route to handle GET request to /api/user
    app.Get("/api/user", func(ctx *lightning.Context) {
        session := ctx.GetData("session")
        // write your logic here...
        fmt.Println(session)

        ctx.Text(200, "hello world")
    })

    // Run the app
    app.Run()
}

In the provided code block, we can see an example of how to use the Contextual Data feature in the Lightning framework. The code sets up two middleware functions that use the ctx.SetData() method to store session data in the context of the request. The first middleware function sets the session data, while the second middleware function retrieves the session data using the ctx.GetData() method.

In addition to middleware functions, the Contextual Data feature can also be used in route handlers. In the provided code block, we can see an example of a route handler that retrieves the session data using the ctx.GetData() method.

app.Get("/api/user", func(ctx *lightning.Context) {
    session := ctx.GetData("session")
    // write your logic here...
})

Overall, the Contextual Data feature in the Lightning framework provides a powerful and flexible way to store and retrieve data within the context of a request. By using this feature, developers can easily manage session data, user information, and other request-specific data in their applications.