Return errors instead of logging/go modules/comments

go.mod

@@ -0,0 +1,5 @@
+module github.com/dpapathanasiou/go-recaptcha
+
+go 1.13
+
+require github.com/pkg/errors v0.8.1

go.sum

@@ -0,0 +1,2 @@
+github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
+github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=

recaptcha.go

@@ -8,8 +8,8 @@ package recaptcha
 
 import (
 	"encoding/json"
+	"fmt"
 	"io/ioutil"
-	"log"
 	"net/http"
 	"net/url"
 	"time"
@@ -28,44 +28,38 @@ const recaptchaServerName = "https://www.google.com/recaptcha/api/siteverify"
 
 var recaptchaPrivateKey string
 
-// check uses the client ip address, the challenge code from the reCaptcha form,
-// and the client's response input to that challenge to determine whether or not
-// the client answered the reCaptcha input question correctly.
-// It returns a boolean value indicating whether or not the client answered correctly.
-func check(remoteip, response string) (r RecaptchaResponse, err error) {
+// check will construct the request to the verification API, send it, and return the result.
+func check(remoteip, response string) (RecaptchaResponse, error) {
+	var r RecaptchaResponse
 	resp, err := http.PostForm(recaptchaServerName,
 		url.Values{"secret": {recaptchaPrivateKey}, "remoteip": {remoteip}, "response": {response}})
 	if err != nil {
-		log.Printf("Post error: %s\n", err)
-		return
+		return r, fmt.Errorf("post error: %w", err)
 	}
 	defer resp.Body.Close()
 	body, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
-		log.Println("Read error: could not read body: %s", err)
-		return
+		return r, fmt.Errorf("read error: could not read body: %w", err)
 	}
 	err = json.Unmarshal(body, &r)
 	if err != nil {
-		log.Println("Read error: got invalid JSON: %s", err)
-		return
+		return r, fmt.Errorf("read error: JSON unmarshal error: %w", err)
 	}
-	return
+	return r, nil
 }
 
-// Confirm is the public interface function.
-// It calls check, which the client ip address, the challenge code from the reCaptcha form,
-// and the client's response input to that challenge to determine whether or not
-// the client answered the reCaptcha input question correctly.
-// It returns a boolean value indicating whether or not the client answered correctly.
+// Confirm is the public interface function that validates the reCAPTCHA token.
+// It accepts the client ip address and the token returned to the client after completing the challenge.
+// It returns a boolean value indicating whether or not the client token is authentic, meaning the challenge
+// was answered correctly.
 func Confirm(remoteip, response string) (result bool, err error) {
 	resp, err := check(remoteip, response)
 	result = resp.Success
 	return
 }
 
-// Init allows the webserver or code evaluating the reCaptcha form input to set the
-// reCaptcha private key (string) value, which will be different for every domain.
+// Init allows the webserver or code evaluating the reCAPTCHA token input to set the
+// reCAPTCHA private key (string) value, which will be different for every domain.
 func Init(key string) {
 	recaptchaPrivateKey = key
 }