Allow filtering /api/state using jq like ?jq=.result (#10577)

server/http_handler.go

@@ -8,6 +8,7 @@ import (
 	"math"
 	"net/http"
 	"strconv"
+	"strings"
 	"text/template"
 	"time"
 
@@ -16,7 +17,9 @@ import (
 	"github.com/evcc-io/evcc/core/site"
 	"github.com/evcc-io/evcc/server/assets"
 	"github.com/evcc-io/evcc/util"
+	"github.com/evcc-io/evcc/util/jq"
 	"github.com/gorilla/mux"
+	"github.com/itchyny/gojq"
 )
 
 var ignoreState = []string{"releaseNotes"} // excessive size
@@ -164,7 +167,34 @@ func stateHandler(cache *util.Cache) http.HandlerFunc {
 		for _, k := range ignoreState {
 			delete(res, k)
 		}
+
 		encodeFloats(res)
+
+		if q := r.URL.Query().Get("jq"); q != "" {
+			q = strings.TrimPrefix(q, ".result")
+
+			query, err := gojq.Parse(q)
+			if err != nil {
+				jsonError(w, http.StatusBadRequest, err)
+				return
+			}
+
+			b, err := json.Marshal(res)
+			if err != nil {
+				jsonError(w, http.StatusBadRequest, err)
+				return
+			}
+
+			res, err := jq.Query(query, b)
+			if err != nil {
+				jsonError(w, http.StatusBadRequest, err)
+				return
+			}
+
+			jsonWrite(w, res)
+			return
+		}
+
 		jsonResult(w, res)
 	}
 }

util/jq/jq.go

@@ -8,7 +8,7 @@ import (
 	"github.com/itchyny/gojq"
 )
 
-// Query executes a compiled jq query against given input. It expects a single result only.
+// Query executes a compiled jq query against given json. It expects a single result only.
 func Query(query *gojq.Query, input []byte) (interface{}, error) {
 	var j interface{}
 	if err := json.Unmarshal(input, &j); err != nil {