Forward server error messages to the caller

Fixes #18.

acme/client.go

@@ -121,9 +121,8 @@ func (c *Client) Register() (*RegistrationResource, error) {
 	}
 	defer resp.Body.Close()
 
-	if resp.StatusCode == http.StatusConflict {
-		// REVIEW: should this return an error?
-		return nil, errors.New("This account is already registered with this CA.")
+	if resp.StatusCode >= http.StatusBadRequest {
+		return nil, handleHTTPError(resp)
 	}
 
 	var serverReg Registration
@@ -167,7 +166,7 @@ func (c *Client) AgreeToTOS() error {
 	defer resp.Body.Close()
 
 	if resp.StatusCode != http.StatusAccepted {
-		return fmt.Errorf("The server returned %d but we expected %d", resp.StatusCode, http.StatusAccepted)
+		return handleHTTPError(resp)
 	}
 
 	return nil
@@ -216,9 +215,8 @@ func (c *Client) RevokeCertificate(certificate []byte) error {
 	}
 	defer resp.Body.Close()
 
-	if resp.StatusCode != 200 {
-		body, _ := ioutil.ReadAll(resp.Body)
-		return fmt.Errorf("The server returned an error while trying to revoke the certificate.\n%s", body)
+	if resp.StatusCode != http.StatusOK {
+		return handleHTTPError(resp)
 	}
 
 	return nil
@@ -369,8 +367,7 @@ func (c *Client) getChallenges(domains []string) []*authorizationResource {
 			}
 
 			if resp.StatusCode != http.StatusCreated {
-				errc <- fmt.Errorf("Getting challenges for %s failed. Got status %d but expected %d",
-					domain, resp.StatusCode, http.StatusCreated)
+				errc <- handleHTTPError(resp)
 			}
 
 			links := parseLinks(resp.Header["Link"])
@@ -523,7 +520,7 @@ func (c *Client) requestCertificate(authz *authorizationResource, result chan Ce
 
 			break
 		default:
-			logger().Printf("[%s] The server returned an unexpected status code %d.", authz.Domain, resp.StatusCode)
+			errc <- handleHTTPError(resp)
 			return
 		}
 

acme/error.go

@@ -0,0 +1,30 @@
+package acme
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+)
+
+// Error asdf
+type Error struct {
+	StatusCode int    `json:"status,omitempty"`
+	Type       string `json:"type"`
+	Detail     string `json:"detail"`
+}
+
+func (e Error) Error() string {
+	return fmt.Sprintf("[%d] Type: %s Detail: %s", e.StatusCode, e.Type, e.Detail)
+}
+
+func handleHTTPError(resp *http.Response) error {
+	var errorDetail Error
+	decoder := json.NewDecoder(resp.Body)
+	err := decoder.Decode(&errorDetail)
+	if err != nil {
+		return err
+	}
+
+	errorDetail.StatusCode = resp.StatusCode
+	return errorDetail
+}

acme/simple_http_challenge.go

@@ -48,6 +48,10 @@ func (s *simpleHTTPChallenge) Solve(chlng challenge, domain string) error {
 	var challengeResponse challenge
 Loop:
 	for {
+		if resp.StatusCode >= http.StatusBadRequest {
+			return handleHTTPError(resp)
+		}
+
 		err = json.NewDecoder(resp.Body).Decode(&challengeResponse)
 		resp.Body.Close()
 		if err != nil {
@@ -61,10 +65,8 @@ Loop:
 		case "pending":
 			break
 		case "invalid":
-			logger().Print("The server could not validate our request.")
 			return errors.New("The server could not validate our request.")
 		default:
-			logger().Print("The server returned an unexpected state.")
 			return errors.New("The server returned an unexpected state.")
 		}