Add RSS-Bridge integration

internal/integration/rssbridge/rssbridge.go

@@ -0,0 +1,45 @@
+package rssbridge // import "miniflux.app/integration/rssbridge"
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+)
+
+type Bridge struct {
+	URL        string     `json:"url"`
+	BridgeMeta BridgeMeta `json:"bridgeMeta"`
+}
+
+type BridgeMeta struct {
+	Name string `json:"name"`
+}
+
+func DetectBridges(rssbridgeURL, websiteURL string) (bridgeResponse []Bridge, err error) {
+	u, err := url.Parse(rssbridgeURL)
+	if err != nil {
+		return nil, err
+	}
+	values := u.Query()
+	values.Add("action", "findfeed")
+	values.Add("format", "atom")
+	values.Add("url", websiteURL)
+	u.RawQuery = values.Encode()
+
+	response, err := http.Get(u.String())
+	if err != nil {
+		return nil, err
+	}
+	defer response.Body.Close()
+	if response.StatusCode == http.StatusNotFound {
+		return
+	}
+	if response.StatusCode > 400 {
+		return nil, fmt.Errorf("RSS-Bridge: server failure (%d)", response.StatusCode)
+	}
+	if err := json.NewDecoder(response.Body).Decode(&bridgeResponse); err != nil {
+		return nil, fmt.Errorf("RSS-Bridge: unable to decode bridge response: %w", err)
+	}
+	return
+}