URL Query Parameters

Learn how to handle URL query parameters in Iris.

Basic Query Parameters

package main

import "github.com/kataras/iris/v12"

func main() {
    app := iris.New()

    // GET /search?q=example&page=1
    app.Get("/search", func(ctx iris.Context) {
        query := ctx.URLParam("q")
        page := ctx.URLParamIntDefault("page", 1)

        ctx.JSON(iris.Map{
            "query": query,
            "page": page,
        })
    })

    app.Listen(":8080")
}

Multiple Values

app.Get("/tags", func(ctx iris.Context) {
    // GET /tags?tag=go&tag=web&tag=iris
    tags := ctx.URLParamSlice("tag")

    ctx.JSON(iris.Map{
        "tags": tags,
    })
})

Type Conversion

app.Get("/filters", func(ctx iris.Context) {
    // String parameter
    name := ctx.URLParam("name")

    // Integer parameter with default
    page := ctx.URLParamIntDefault("page", 1)

    // Float parameter
    price := ctx.URLParamFloat64Default("price", 0.0)

    // Boolean parameter
    active := ctx.URLParamBool("active")

    ctx.JSON(iris.Map{
        "name": name,
        "page": page,
        "price": price,
        "active": active,
    })
})

Required Parameters

app.Get("/required", func(ctx iris.Context) {
    id := ctx.URLParam("id")
    if id == "" {
        ctx.StopWithProblem(iris.StatusBadRequest, iris.NewProblem().
            Title("Validation Error").
            Detail("ID parameter is required"))
        return
    }

    ctx.JSON(iris.Map{
        "id": id,
    })
})

Best Practices

1. Validation:

   • Validate required parameters
   • Check parameter types
   • Set default values
   • Handle missing values
   • Sanitize input

2. Security:

   • Validate parameter length
   • Check parameter format
   • Prevent injection
   • Escape special characters
   • Log suspicious input

3. Performance:

   • Cache parsed values
   • Use appropriate types
   • Handle large queries
   • Monitor query size
   • Optimize parsing

4. Error Handling:

   • Provide clear messages
   • Handle invalid types
   • Log validation errors
   • Return proper status
   • Document requirements