PSA: simplify api (#2022)

vehicle/psa/api.go

@@ -2,11 +2,11 @@ package psa
 
 import (
 	"fmt"
-	"net/http"
 	"net/url"
 
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/request"
+	"github.com/evcc-io/evcc/util/transport"
 	"golang.org/x/oauth2"
 )
 
@@ -30,56 +30,47 @@ func NewAPI(log *util.Logger, identity oauth2.TokenSource, realm, id string) *AP
 		id:     id,
 	}
 
-	// replace client transport with authenticated transport
-	v.Client.Transport = &oauth2.Transport{
-		Source: identity,
-		Base:   v.Client.Transport,
+	// replace client transport with authenticated transport plus headers
+	v.Client.Transport = &transport.Decorator{
+		Base: &oauth2.Transport{
+			Source: identity,
+			Base:   v.Client.Transport,
+		},
+		Decorator: transport.DecorateHeaders(map[string]string{
+			"Accept":             "application/hal+json",
+			"X-Introspect-Realm": v.realm,
+		}),
 	}
 
 	return v
 }
 
+func (v *API) clientID() string {
+	return url.Values{
+		"client_id": []string{v.id},
+	}.Encode()
+}
+
 // Vehicles implements the /vehicles response
 func (v *API) Vehicles() ([]Vehicle, error) {
-	data := url.Values{
-		"client_id": []string{v.id},
-	}
-
-	uri := fmt.Sprintf("%s/user/vehicles?%s", BaseURL, data.Encode())
-	req, err := request.New(http.MethodGet, uri, nil, map[string]string{
-		"Accept":             "application/hal+json",
-		"X-Introspect-Realm": v.realm,
-	})
-
 	var res struct {
 		Embedded struct {
 			Vehicles []Vehicle
 		} `json:"_embedded"`
 	}
-	if err == nil {
-		err = v.DoJSON(req, &res)
-	}
+
+	uri := fmt.Sprintf("%s/user/vehicles?%s", BaseURL, v.clientID())
+	err := v.GetJSON(uri, &res)
 
 	return res.Embedded.Vehicles, err
 }
 
 // Status implements the /vehicles/<vid>/status response
 func (v *API) Status(vid string) (Status, error) {
-	data := url.Values{
-		"client_id": []string{v.id},
-	}
+	var res Status
 
-	// BaseURL is the API base url
-	uri := fmt.Sprintf("%s/user/vehicles/%s/status?%s", BaseURL, vid, data.Encode())
-	req, err := request.New(http.MethodGet, uri, nil, map[string]string{
-		"Accept":             "application/hal+json",
-		"X-Introspect-Realm": v.realm,
-	})
+	uri := fmt.Sprintf("%s/user/vehicles/%s/status?%s", BaseURL, vid, v.clientID())
+	err := v.GetJSON(uri, &res)
 
-	var status Status
-	if err == nil {
-		err = v.DoJSON(req, &status)
-	}
-
-	return status, err
+	return res, err
 }