Refactor common code for http requests and enable logging

api/http.go

@@ -0,0 +1,94 @@
+package api
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+)
+
+type HTTPHelper struct {
+	Log    *Logger
+	Client *http.Client
+}
+
+// NewHTTPHelper creates http helper for simplified PUT GET logic
+func NewHTTPHelper(log *Logger) *HTTPHelper {
+	r := &HTTPHelper{
+		Log:    log,
+		Client: &http.Client{},
+	}
+	return r
+}
+
+// Response codes other than HTTP 200 or 204 are raised as error
+func (r *HTTPHelper) readBody(resp *http.Response, err error) ([]byte, error) {
+	if err != nil {
+		return []byte{}, err
+	}
+	defer resp.Body.Close()
+
+	b, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return []byte{}, err
+	}
+
+	if r.Log != nil {
+		r.Log.TRACE.Printf("%s\n%s", resp.Request.URL.String(), string(b))
+	}
+
+	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusNoContent {
+		return b, fmt.Errorf("unexpected response %d: %s", resp.StatusCode, string(b))
+	}
+
+	return b, nil
+}
+
+func (r *HTTPHelper) decodeJSON(resp *http.Response, err error, res interface{}) ([]byte, error) {
+	b, err := r.readBody(resp, err)
+	if err == nil {
+		err = json.Unmarshal(b, &res)
+	}
+
+	return b, err
+}
+
+// Get executes HTTP GET request returns the response body
+func (r *HTTPHelper) Get(url string) ([]byte, error) {
+	resp, err := r.Client.Get(url)
+	return r.readBody(resp, err)
+}
+
+// Put executes HTTP PUT request returns the response body
+func (r *HTTPHelper) Put(url string, body []byte) ([]byte, error) {
+	req, err := http.NewRequest(http.MethodPut, url, bytes.NewBuffer(body))
+	if err != nil {
+		return []byte{}, err
+	}
+
+	resp, err := r.Client.Do(req)
+	return r.readBody(resp, err)
+}
+
+// RequestJSON executes HTTP request and decodes JSON response
+func (r *HTTPHelper) RequestJSON(req *http.Request, res interface{}) ([]byte, error) {
+	resp, err := r.Client.Do(req)
+	return r.decodeJSON(resp, err, res)
+}
+
+// GetJSON executes HTTP GET request and decodes JSON response
+func (r *HTTPHelper) GetJSON(url string, res interface{}) ([]byte, error) {
+	resp, err := r.Client.Get(url)
+	return r.decodeJSON(resp, err, res)
+}
+
+// PutJSON executes HTTP PUT request and returns the response body
+func (r *HTTPHelper) PutJSON(url string, data interface{}) ([]byte, error) {
+	body, err := json.Marshal(data)
+	if err != nil {
+		return []byte{}, err
+	}
+
+	return r.Put(url, body)
+}

charger/config.go

@@ -1,11 +1,6 @@
 package charger
 
 import (
-	"bytes"
-	"encoding/json"
-	"fmt"
-	"io/ioutil"
-	"net/http"
 	"strings"
 
 	"github.com/andig/evcc/api"
@@ -36,45 +31,3 @@ func NewFromConfig(log *api.Logger, typ string, other map[string]interface{}) ap
 
 	return c
 }
-
-func getJSON(url string, result interface{}) (*http.Response, []byte, error) {
-	resp, err := http.Get(url)
-	if err != nil {
-		return resp, []byte{}, err
-	}
-	defer resp.Body.Close()
-
-	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return resp, body, err
-	}
-
-	if resp.StatusCode == http.StatusOK {
-		err = json.Unmarshal(body, &result)
-		return resp, body, err
-	}
-
-	return resp, body, fmt.Errorf("unexpected status %d", resp.StatusCode)
-}
-
-func putJSON(url string, request interface{}) (*http.Response, []byte, error) {
-	data, err := json.Marshal(request)
-	if err != nil {
-		return nil, []byte{}, err
-	}
-
-	client := &http.Client{}
-	req, err := http.NewRequest(http.MethodPut, url, bytes.NewBuffer(data))
-	if err != nil {
-		return nil, []byte{}, err
-	}
-
-	resp, err := client.Do(req)
-	if err != nil {
-		return resp, []byte{}, err
-	}
-	defer resp.Body.Close()
-
-	body, err := ioutil.ReadAll(resp.Body)
-	return resp, body, err
-}

charger/go-e.go

@@ -26,7 +26,7 @@ type goeStatusResponse struct {
 
 // GoE charger implementation
 type GoE struct {
-	log *api.Logger
+	*api.HTTPHelper
 	URI string
 }
 
@@ -41,11 +41,11 @@ func NewGoEFromConfig(log *api.Logger, other map[string]interface{}) api.Charger
 // NewGoE creates GoE charger
 func NewGoE(URI string) *GoE {
 	c := &GoE{
-		URI: URI,
-		log: api.NewLogger("go-e"),
+		HTTPHelper: api.NewHTTPHelper(api.NewLogger("go-e")),
+		URI:        URI,
 	}
 
-	c.log.WARN.Println("-- experimental --")
+	c.HTTPHelper.Log.WARN.Println("-- experimental --")
 
 	return c
 }
@@ -55,51 +55,55 @@ func (c *GoE) apiURL(api apiFunction) string {
 }
 
 func (c *GoE) getJSON(url string, result interface{}) error {
-	resp, body, err := getJSON(url, result)
-	c.log.TRACE.Printf("GET %s: %s", url, string(body))
-
-	if err != nil && len(body) == 0 {
-		return err
+	b, err := c.GetJSON(url, result)
+	if err != nil && len(b) > 0 {
+		var error goeStatusResponse
+		if err := json.Unmarshal(b, &error); err != nil {
+			return err
+		}
+
+		return fmt.Errorf("response code: %d", error.Err)
 	}
 
-	var error goeStatusResponse
-	_ = json.Unmarshal(body, &error)
-
-	return fmt.Errorf("api %d: %d", resp.StatusCode, error.Err)
+	return err
 }
 
 // Status implements the Charger.Status interface
 func (c *GoE) Status() (api.ChargeStatus, error) {
 	var status goeStatusResponse
-	err := c.getJSON(c.apiURL(goeStatus), status)
+	if err := c.getJSON(c.apiURL(goeStatus), status); err != nil {
+		return api.StatusNone, err
+	}
 
 	switch status.Car {
 	case 1:
-		return api.StatusA, err
+		return api.StatusA, nil
 	case 2:
-		return api.StatusC, err
+		return api.StatusC, nil
 	case 3:
-		return api.StatusB, err
+		return api.StatusB, nil
 	case 4:
-		return api.StatusB, err
+		return api.StatusB, nil
+	default:
+		return api.StatusNone, fmt.Errorf("unknown result %d", status.Car)
 	}
-
-	return api.StatusNone, fmt.Errorf("unknown result %d", status.Car)
 }
 
 // Enabled implements the Charger.Enabled interface
 func (c *GoE) Enabled() (bool, error) {
 	var status goeStatusResponse
-	err := c.getJSON(c.apiURL(goeStatus), status)
+	if err := c.getJSON(c.apiURL(goeStatus), status); err != nil {
+		return false, err
+	}
 
 	switch status.Alw {
 	case 0:
-		return false, err
+		return false, nil
 	case 1:
-		return true, err
+		return true, nil
+	default:
+		return false, fmt.Errorf("unknown result %d", status.Alw)
 	}
-
-	return false, fmt.Errorf("unknown result %d", status.Alw)
 }
 
 // Enable implements the Charger.Enable interface

charger/nrgkick.go

@@ -3,7 +3,6 @@ package charger
 import (
 	"encoding/json"
 	"fmt"
-	"net/http"
 
 	"github.com/andig/evcc/api"
 )
@@ -24,7 +23,7 @@ type NRGMeasurements struct {
 	ChargingPower  float64
 }
 
-// NRGSettings is the /api/setings request/response
+// NRGSettings is the /api/settings request/response
 type NRGSettings struct {
 	Info   NRGInfo `json:"omitempty"`
 	Values NRGValues
@@ -59,7 +58,7 @@ type NRGDeviceMetadata struct {
 
 // NRGKick charger implementation
 type NRGKick struct {
-	log        *api.Logger
+	*api.HTTPHelper
 	IP         string
 	MacAddress string
 	Password   string
@@ -76,13 +75,13 @@ func NewNRGKickFromConfig(log *api.Logger, other map[string]interface{}) api.Cha
 // NewNRGKick creates NRGKick charger
 func NewNRGKick(IP, MacAddress, Password string) *NRGKick {
 	nrg := &NRGKick{
+		HTTPHelper: api.NewHTTPHelper(api.NewLogger("kick")),
 		IP:         IP,
 		MacAddress: MacAddress,
 		Password:   Password,
-		log:        api.NewLogger("kick"),
 	}
 
-	nrg.log.WARN.Println("-- experimental --")
+	nrg.HTTPHelper.Log.WARN.Println("-- experimental --")
 
 	return nrg
 }
@@ -92,35 +91,31 @@ func (nrg *NRGKick) apiURL(api apiFunction) string {
 }
 
 func (nrg *NRGKick) getJSON(url string, result interface{}) error {
-	resp, body, err := getJSON(url, result)
-	nrg.log.TRACE.Printf("GET %s: %s", url, string(body))
-
-	if err != nil && len(body) == 0 {
-		return err
+	b, err := nrg.GetJSON(url, result)
+	if err != nil && len(b) > 0 {
+		var error NRGResponse
+		if err := json.Unmarshal(b, &error); err != nil {
+			return err
+		}
+
+		return fmt.Errorf("response: %s", error.Message)
 	}
 
-	var error NRGResponse
-	_ = json.Unmarshal(body, &error)
-
-	return fmt.Errorf("api %d: %s", resp.StatusCode, error.Message)
+	return err
 }
 
 func (nrg *NRGKick) putJSON(url string, request interface{}) error {
-	resp, body, err := putJSON(url, request)
-	nrg.log.TRACE.Printf("PUT %v: %s", resp, string(body))
-
-	if err != nil && len(body) == 0 {
+	b, err := nrg.PutJSON(url, request)
+	if err != nil && len(b) == 0 {
 		return err
 	}
 
-	if resp.StatusCode == http.StatusOK || resp.StatusCode == http.StatusNoContent {
-		return nil
-	}
-
 	var error NRGResponse
-	_ = json.Unmarshal(body, &error)
+	if err := json.Unmarshal(b, &error); err != nil {
+		return err
+	}
 
-	return fmt.Errorf("api %d: %s", resp.StatusCode, error.Message)
+	return fmt.Errorf("response: %s", error.Message)
 }
 
 // Status implements the Charger.Status interface