Add IPv4/IPv6 source from 'icanhazip.com'

Signed-off-by: Mel <mel@rnrd.eu>

2 files changed, 38 insertions, 4 deletions

diff --git a/source/icanhazip.go b/source/icanhazip.go
new file mode 100644
index 0000000..62f2d9f
--- /dev/null
+++ b/source/icanhazip.go
@@ -0,0 +1,29 @@
+package source
+
+import (
+	"log/slog"
+	"net/netip"
+)
+
+type icanhazip struct {
+	log *slog.Logger
+}
+
+var _ Source = (*icanhazip)(nil)
+
+func newICanHazIp(log *slog.Logger) (*icanhazip, error) {
+	return &icanhazip{log: log}, nil
+}
+
+func (icanhazip) Supports(Family) bool { return true }
+
+func (s icanhazip) Lookup(family Family) (netip.Addr, error) {
+	s.log.Info("will look up address from the icanhazip.com service",
+		slog.String("family", string(family)),
+	)
+
+	if family == IPv6 {
+		return fetch("https://ipv6.icanhazip.com", IPv6)
+	}
+	return fetch("https://ipv4.icanhazip.com", IPv4)
+}
diff --git a/source/source.go b/source/source.go
index ffa380a..571abda 100644
--- a/source/source.go
+++ b/source/source.go
@@ -13,10 +13,10 @@ import (
 type Kind string
 
 const (
-	// only the simple generic sources for now!
-	KindStatic Kind = "static"
-	KindURL    Kind = "url"
-	KindFile   Kind = "file"
+	KindStatic    Kind = "static"
+	KindURL       Kind = "url"
+	KindFile      Kind = "file"
+	KindICanHazIp Kind = "icanhazip"
 )
 
 type Family string
@@ -49,6 +49,11 @@ func New(log *slog.Logger, name string, cfg Config) (Source, error) {
 		),
 	)
 
+	if cfg.Kind == KindICanHazIp {
+		return newICanHazIp(log)
+	}
+
+	// all sources below need an explicit family
 	if cfg.Family != IPv4 && cfg.Family != IPv6 {
 		return nil, fmt.Errorf("%s source needs family set to ipv4 or ipv6", cfg.Kind)
 	}