// getResource is the function that handles the GET /resources/:resourceID route.
func getResource(c siesta.Context, w http.ResponseWriter, r *http.Request) {
// Context variables
requestID := c.Get("request-id").(string)
db := c.Get("db").(*DB)
user := c.Get("user").(string)
// Check parameters
var params siesta.Params
resourceID := params.Int("resourceID", -1, "Resource identifier")
err := params.Parse(r.Form)
if err != nil {
log.Printf("[Req %s] %v", requestID, err)
c.Set("error", err.Error())
c.Set("status-code", http.StatusBadRequest)
return
}
// Make sure we have a valid resource ID.
if *resourceID == -1 {
c.Set("error", "invalid or missing resource ID")
c.Set("status-code", http.StatusBadRequest)
return
}
resource, err := db.resource(user, *resourceID)
if err != nil {
c.Set("status-code", http.StatusNotFound)
c.Set("error", "not found")
return
}
c.Set("data", resource)
}
func main() {
// Create a new Service rooted at "/"
service := siesta.NewService("/")
// Here's a handler that uses a URL parameter.
// Example: GET /greet/Bob
service.Route("GET", "/greet/:name", "Greets with a name.",
func(w http.ResponseWriter, r *http.Request) {
var params siesta.Params
name := params.String("name", "", "Person's name")
err := params.Parse(r.Form)
if err != nil {
log.Println("Error parsing parameters!", err)
return
}
fmt.Fprintf(w, "Hello, %s!", *name)
},
)
// Here's a handler that uses a query string parameter.
// Example: GET /square?number=10
service.Route("GET", "/square", "Prints the square of a number.",
func(w http.ResponseWriter, r *http.Request) {
var params siesta.Params
number := params.Int("number", 0, "A number to square")
err := params.Parse(r.Form)
if err != nil {
log.Println("Error parsing parameters!", err)
return
}
fmt.Fprintf(w, "%d * %d = %d.", *number, *number, (*number)*(*number))
},
)
// We can also use both URL and query string parameters.
// Example: GET /exponentiate/10?power=10
service.Route("GET", "/exponentiate/:number", "Exponentiates a number.",
func(w http.ResponseWriter, r *http.Request) {
var params siesta.Params
number := params.Float64("number", 0, "A number to exponentiate")
power := params.Float64("power", 1, "Power")
err := params.Parse(r.Form)
if err != nil {
log.Println("Error parsing parameters!", err)
return
}
fmt.Fprintf(w, "%g ^ %g = %g.", *number, *power, math.Pow(*number, *power))
},
)
// service is an http.Handler, so we can pass it directly to ListenAndServe.
log.Fatal(http.ListenAndServe(":8080", service))
}