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// handler.go
package main
import (
"context"
"fmt"
"net/http"
"time"
"cloud.google.com/go/datastore"
"github.com/go-chi/render"
)
func Index(w http.ResponseWriter, r *http.Request) {
ctx := r.Context()
// Get a list of the most recent visits.
visits, err := queryVisits(ctx, 10)
if err != nil {
msg := fmt.Sprintf("Could not save visit: %v", err)
http.Error(w, msg, http.StatusInternalServerError)
return
}
// Record this visit.
if err := recordVisit(ctx, time.Now(), r.RemoteAddr); err != nil {
msg := fmt.Sprintf("Could not save visit: %v", err)
http.Error(w, msg, http.StatusInternalServerError)
return
}
render.Status(r, http.StatusOK)
list := []render.Renderer{}
for _, visit := range visits {
response := &visitResponse{visit: visit}
list = append(list, response)
}
render.RenderList(w, r, list)
}
type visit struct {
Timestamp time.Time `json:"time"`
UserIP string `json:"ip"`
}
type visitResponse struct {
*visit
}
func (vr *visitResponse) Render(w http.ResponseWriter, r *http.Request) error {
return nil
}
func recordVisit(ctx context.Context, now time.Time, userIP string) error {
v := &visit{
Timestamp: now,
UserIP: userIP,
}
k := datastore.IncompleteKey("Visit", nil)
_, err := datastoreClient.Put(ctx, k, v)
return err
}
func queryVisits(ctx context.Context, limit int64) ([]*visit, error) {
q := datastore.NewQuery("Visit").Order("-Timestamp").Limit(10)
visits := make([]*visit, 0)
_, err := datastoreClient.GetAll(ctx, q, &visits)
return visits, err
}
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