oc-discovery -> conf

daemons/node/location/location.go

@@ -0,0 +1,99 @@
+// Package location resolves the geographic position of this node via IP
+// geolocation and applies a privacy-preserving random offset proportional
+// to the chosen granularity level before publishing the result.
+package location
+
+import (
+	"encoding/json"
+	"fmt"
+	"math/rand"
+	"net/http"
+	"time"
+
+	peer "cloud.o-forge.io/core/oc-lib/models/peer"
+)
+
+// fuzzRadius returns the maximum random offset (in degrees) for each axis
+// given a granularity level.
+//
+//	0 → no location
+//	1 → continent  ±15° lat / ±20° lng
+//	2 → country    ±3°  lat / ±4°  lng  (default)
+//	3 → region     ±0.5° lat / ±0.7° lng
+//	4 → city       ±0.05° lat / ±0.07° lng
+func fuzzRadius(granularity int) (latR, lngR float64) {
+	switch granularity {
+	case 1:
+		return 15.0, 20.0
+	case 2:
+		return 3.0, 4.0
+	case 3:
+		return 0.5, 0.7
+	case 4:
+		return 0.05, 0.07
+	default:
+		return 3.0, 4.0
+	}
+}
+
+// clamp keeps a value inside [min, max].
+func clamp(v, min, max float64) float64 {
+	if v < min {
+		return min
+	}
+	if v > max {
+		return max
+	}
+	return v
+}
+
+// ipAPIResponse is the subset of fields returned by ip-api.com/json.
+type ipAPIResponse struct {
+	Status  string  `json:"status"`
+	Lat     float64 `json:"lat"`
+	Lon     float64 `json:"lon"`
+	Country string  `json:"country"`
+	Region  string  `json:"regionName"`
+	City    string  `json:"city"`
+}
+
+// Geolocate resolves the current public IP location via ip-api.com (free,
+// no key required for non-commercial use), then fuzzes the result according
+// to granularity.
+//
+// Returns nil if granularity == 0 (opt-out) or if the lookup fails.
+func Geolocate(granularity int) *peer.PeerLocation {
+	if granularity == 0 {
+		return nil
+	}
+
+	client := &http.Client{Timeout: 5 * time.Second}
+	resp, err := client.Get("http://ip-api.com/json?fields=status,lat,lon,country,regionName,city")
+	if err != nil {
+		return nil
+	}
+	defer resp.Body.Close()
+
+	var result ipAPIResponse
+	if err := json.NewDecoder(resp.Body).Decode(&result); err != nil || result.Status != "success" {
+		return nil
+	}
+
+	latR, lngR := fuzzRadius(granularity)
+	rng := rand.New(rand.NewSource(time.Now().UnixNano()))
+
+	fuzzedLat := result.Lat + (rng.Float64()*2-1)*latR
+	fuzzedLng := result.Lon + (rng.Float64()*2-1)*lngR
+
+	fuzzedLat = clamp(fuzzedLat, -85.0, 85.0)
+	fuzzedLng = clamp(fuzzedLng, -180.0, 180.0)
+
+	fmt.Printf("[location] granularity=%d raw=(%.4f,%.4f) fuzzed=(%.4f,%.4f)\n",
+		granularity, result.Lat, result.Lon, fuzzedLat, fuzzedLng)
+
+	return &peer.PeerLocation{
+		Latitude:    fuzzedLat,
+		Longitude:   fuzzedLng,
+		Granularity: granularity,
+	}
+}