PageData

Structure

// sdk/stew/types.go
type PageData struct {
    URL     string              // Current URL path (e.g., "/users/42")
    Params  map[string]string   // URL parameters ({id} → "42")
    Query   url.Values          // Query parameters (?page=2)
    Request *http.Request       // Raw HTTP request
    Store   map[string]any      // Free-form map for data storage
}

Template Access

<goscript>
    import "strconv"

    // Current URL
    currentPath := data.URL

    // Dynamic URL parameter (/users/{id})
    userId := data.Params["id"]

    // Query string (?page=2&sort=desc)
    page := data.Query.Get("page")
    sort := data.Query.Get("sort")

    // HTTP Header
    userAgent := data.Request.Header.Get("User-Agent")

    // Free-form Store
    data.Store["user"] = "Baptiste"
</goscript>

<p>URL: {{ currentPath }}</p>
<p>User #{{ userId }}</p>

Propagation Through Layouts

The same PageData object is created once per request in the router and passed to the entire rendering chain (root layout → nested layouts → page → components). Changes made to data.Store in a <goscript> are visible throughout the entire rendering of that request.

Accessing Data in Wasm

To avoid JSON unmarshaling boilerplate, Stew provides a virtual import stew/data. When imported, a local data variable (of type stew.PageData) becomes available in your client-side scope.

<goscript client>
    import "stew/data"

    func HandleClick() {
        // Access URL parameters directly
        userId := data.Params["id"]
        
        // Access the free-form Store
        if title, ok := data.Store["Title"].(string); ok {
            println("Page title: " + title)
        }
        
        // Current URL
        println("Current path: " + data.URL)
    }
</goscript>

Low-level JSON Serialization (Manual)

When a page contains a <goscript client> block, the compiler automatically injects the state as JSON:

<script type="application/json" id="stew-pagedata">
    {"URL":"/","Params":{},"Store":{"Title":"My App"},...}
</script>

If you need to unmarshal it manually (low-level access):

<goscript client>
    import "encoding/json"

    pageData := wasm.GetPageDataJSON() // Get raw JSON string
    var state map[string]interface{}
    json.Unmarshal([]byte(pageData), &state)
</goscript>