1 files changed, 117 insertions, 0 deletions
diff --git a/analytics/analytics.go b/analytics/analytics.go
new file mode 100644
index 0000000..16d12c5
--- /dev/null
+++ b/analytics/analytics.go
@@ -0,0 +1,117 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net"
+	"net/http"
+	"net/http/fcgi"
+	"time"
+
+	"blitiri.com.ar/go/systemd"
+	"github.com/jackc/pgx/v4"
+	"github.com/jackc/pgx/v4/pgxpool"
+)
+
+type Event struct {
+	Created_ts int64
+	Kind       string
+	Details    string
+}
+
+func getListener() (net.Listener, error) {
+	listeners, err := systemd.Listeners()
+	if err != nil {
+		return nil, fmt.Errorf("unable to get systemd listeners: %w", err)
+	}
+	count := 0
+	for _, listeners := range listeners {
+		count += len(listeners)
+		if count == 1 {
+			return listeners[0], nil
+		}
+	}
+	return nil, fmt.Errorf("expected 1 systemd fd passed, got %v", count)
+}
+
+func httpEnd(w http.ResponseWriter, r *http.Request, content string, code int) {
+	log.Printf("%v %d %d %s", r.RemoteAddr, r.ContentLength, code, content)
+	http.Error(w, content, code)
+}
+
+func main() {
+	conn, err := pgxpool.Connect(context.Background(), "")
+	if err != nil {
+		log.Fatal("Unable to connect to database: ", err)
+	}
+	defer conn.Close()
+
+	http.HandleFunc("/analytics", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == "GET" {
+			if url, ok := r.URL.Query()["url"]; ok {
+				if len(url) > 1 {
+					httpEnd(w, r, "too many urls", 400)
+				} else {
+					http.Redirect(w, r, url[0], 303)
+					_, err = conn.Exec(context.Background(), "insert into events(created_ts, ip_addr, kind, details) values ($1, $2, $3, $4)", time.Now(), r.RemoteAddr, "r", url[0])
+					if err != nil {
+						log.Printf("%v 0 303 db error: %s", r.RemoteAddr, err)
+						return
+					}
+					log.Printf("%v 0 303 ok", r.RemoteAddr)
+				}
+			} else {
+				httpEnd(w, r, "missing url for GET", 400)
+			}
+			return
+		}
+		if r.Method != "POST" {
+			httpEnd(w, r, "method not allowed: "+r.Method, 405)
+			return
+		}
+		if r.ContentLength <= 0 {
+			httpEnd(w, r, "length required", 411)
+			return
+		}
+		if r.ContentLength > 1048576 {
+			httpEnd(w, r, "too much data", 413)
+			return
+		}
+
+		data, err := io.ReadAll(r.Body)
+		if err != nil {
+			httpEnd(w, r, "read error", 400)
+			return
+		}
+		var events []Event
+		if err := json.Unmarshal(data, &events); err != nil {
+			log.Print(err)
+			httpEnd(w, r, "bad json", 400)
+			return
+		}
+
+		_, err = conn.CopyFrom(
+			r.Context(),
+			pgx.Identifier{"events"},
+			[]string{"created_ts", "ip_addr", "kind", "details"},
+			pgx.CopyFromSlice(len(events), func(i int) ([]interface{}, error) {
+				return []interface{}{time.Unix(events[i].Created_ts/1000, events[i].Created_ts%1000*1000000), r.RemoteAddr, events[i].Kind, events[i].Details}, nil
+			}),
+		)
+		if err != nil {
+			log.Printf("%v %d 500 db error: %s", r.RemoteAddr, r.ContentLength, err)
+			http.Error(w, "db error", 500)
+		} else {
+			httpEnd(w, r, "ok", 200)
+		}
+	})
+
+	l, err := getListener()
+	if err != nil {
+		log.Fatal(err)
+	}
+	fcgi.Serve(l, nil)
+}