Add user agent indexed by sha1

1 files changed, 33 insertions, 0 deletions

diff --git a/user_agent.go b/user_agent.go
new file mode 100644
index 0000000..cbb831b
--- /dev/null
+++ b/user_agent.go
@@ -0,0 +1,33 @@
+package sws
+
+import (
+	"crypto/sha1"
+	"fmt"
+	"net/http"
+	"time"
+)
+
+type UserAgent struct {
+	Hash       string    `json:"hash"`
+	Name       string    `json:"name"`
+	LastSeenAt time.Time `json:"last_seen_at"`
+}
+
+func UserAgentHash(s string) string {
+	return fmt.Sprintf("%x", sha1.Sum([]byte(s)))
+}
+
+func UserAgentFromRequest(r *http.Request) (*UserAgent, error) {
+	q := r.URL.Query()
+	agent := q.Get("u")
+	if agent == "" {
+		return nil, nil
+	}
+	ua := r.UserAgent()
+
+	return &UserAgent{
+		Name:       ua,
+		LastSeenAt: time.Now(),
+		Hash:       UserAgentHash(ua),
+	}, nil
+}