func main() {
// Create a new Service rooted at "/"
service := siesta.NewService("/")
// Route accepts normal http.Handlers.
service.Route("GET", "/", "Sends 'Hello, world!'", func(w http.ResponseWriter, r *http.Request) {
fmt.Fprintln(w, "Hello, world!")
})
// Let's create some simple "middleware."
// This handler will accept a Context argument and will add the current
// time to it.
timestamper := func(c siesta.Context, w http.ResponseWriter, r *http.Request) {
c.Set("start", time.Now())
}
// This is the handler that will actually send data back to the client.
// It also takes a Context argument so it can get the timestamp from the
// previous handler.
timeHandler := func(c siesta.Context, w http.ResponseWriter, r *http.Request) {
start := c.Get("start").(time.Time)
delta := time.Now().Sub(start)
fmt.Fprintf(w, "That took %v.\n", delta)
}
// We can compose these handlers together.
timeHandlers := siesta.Compose(timestamper, timeHandler)
// Finally, we'll add the new handler we created using composition to a new route.
service.Route("GET", "/time", "Sends how long it took to send a message", timeHandlers)
// service is an http.Handler, so we can pass it directly to ListenAndServe.
log.Fatal(http.ListenAndServe(":8080", service))
}
func main() {
// Create a new service rooted at /.
service := siesta.NewService("/")
// requestIdentifier assigns an ID to every request
// and adds it to the context for that request.
// This is useful for logging.
service.AddPre(requestIdentifier)
// Add access to the state via the context in every handler.
service.AddPre(func(c siesta.Context, w http.ResponseWriter, r *http.Request) {
c.Set("db", state)
})
// We'll add the authenticator middleware to the "pre" chain.
// It will ensure that every request has a valid token.
service.AddPre(authenticator)
// Response generation
service.AddPost(responseGenerator)
service.AddPost(responseWriter)
// Custom 404 handler
service.SetNotFound(func(c siesta.Context, w http.ResponseWriter, r *http.Request) {
c.Set("status-code", http.StatusNotFound)
c.Set("error", "not found")
})
// Routes
service.Route("GET", "/resources/:resourceID", "Retrieves a resource",
getResource)
log.Println("Listening on :8080")
panic(http.ListenAndServe(":8080", service))
}
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))
}
func initSiesta() {
h := siesta.NewService("/")
h.Route("GET", "/", "",
func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/plain; charset=utf-8")
fmt.Fprintf(w, "Hello, World")
})
h.Route("GET", "/:name", "",
func(w http.ResponseWriter, r *http.Request) {
var params siesta.Params
name := params.String("name", "", "")
params.Parse(r.Form)
w.Header().Set("Content-Type", "text/plain; charset=utf-8")
fmt.Fprintf(w, "Hello, %s", *name)
})
registerHandler("siesta", h)
}
func (s *APIServer) Run() {
service := siesta.NewService("/")
service.AddPre(func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Access-Control-Allow-Origin", "*")
w.Header().Set("Access-Control-Allow-Headers", r.Header.Get("Access-Control-Request-Headers"))
})
service.AddPost(func(c siesta.Context, w http.ResponseWriter, r *http.Request, q func()) {
resp := c.Get(responseKey)
err, _ := c.Get(errorKey).(string)
if resp == nil && err == "" {
return
}
enc := json.NewEncoder(w)
enc.Encode(APIResponse{
Data: resp,
Error: err,
})
})
service.Route("GET", "/", "Default page", func(c siesta.Context, w http.ResponseWriter, r *http.Request) {
c.Set(responseKey, "Welcome to the Cistern API!")
})
service.Route("GET", "/devices", "Lists sources", func(c siesta.Context, w http.ResponseWriter, r *http.Request) {
type ipHostname struct {
IP string `json:"ip"`
Hostname string `json:"hostname,omitempty"`
}
devices := []ipHostname{}
for _, dev := range s.deviceRegistry.Devices() {
devices = append(devices, ipHostname{
IP: dev.IP().String(),
Hostname: dev.Hostname(),
})
}
c.Set(responseKey, devices)
})
service.Route("GET", "/devices/:device/metrics",
"Lists metrics for a device",
func(c siesta.Context, w http.ResponseWriter, r *http.Request) {
var params siesta.Params
device := params.String("device", "", "Device name")
err := params.Parse(r.Form)
if err != nil {
c.Set(errorKey, err.Error())
return
}
address := net.ParseIP(*device)
dev, present := s.deviceRegistry.Lookup(address)
if !present {
c.Set(errorKey, "device not found")
return
}
c.Set(responseKey, dev.Metrics())
})
service.Route("GET", "/devices/:device/flows",
"Lists top flows for a device",
func(c siesta.Context, w http.ResponseWriter, r *http.Request) {
var params siesta.Params
device := params.String("device", "", "Device name")
err := params.Parse(r.Form)
if err != nil {
c.Set(errorKey, err.Error())
return
}
address := net.ParseIP(*device)
dev, present := s.deviceRegistry.Lookup(address)
if !present {
c.Set(errorKey, "device not found")
return
}
type flowsResponse struct {
ByBytes []flows.Flow `json:"byBytes"`
ByPackets []flows.Flow `json:"byPackets"`
}
topTalkers := dev.TopTalkers()
if topTalkers == nil {
c.Set(errorKey, "No active flows")
return
}
resp := flowsResponse{
ByBytes: topTalkers.ByBytes(),
ByPackets: topTalkers.ByPackets(),
}
c.Set(responseKey, resp)
})
service.Route("OPTIONS", "/series/query",
"Accepts an OPTIONS request",
func(w http.ResponseWriter, r *http.Request) {
// Doesn't do anything
})
service.Route("POST", "/series/query",
"Lists metrics for a device",
s.querySeriesRoute())
http.Handle("/", service)
go http.ListenAndServe(s.addr, nil)
}
