refactor: enhance error handling in client creation and context management

client/client.go

@@ -1,6 +1,9 @@
 package client
 
-import "context"
+import (
+	"context"
+	"errors"
+)
 
 type Client struct {
 	config *Configuration
@@ -17,7 +20,7 @@ type accessTokenRequest struct {
 	ClientSecret string `json:"client_secret"`
 }
 
-func NewClient(config *Configuration) *Client {
+func NewClient(config *Configuration) (*Client, error) {
 
 	client := &Client{
 		config: config,
@@ -25,12 +28,12 @@ func NewClient(config *Configuration) *Client {
 
 	token, err := getToken(client.config)
 	if err != nil {
-		return nil
+		return nil, errors.New("failed to get token: " + err.Error())
 	}
 
 	client.token = token
 
-	return client
+	return client, nil
 }
 
 func FromContext(ctx context.Context) *Client {
@@ -46,15 +49,16 @@ func FromContext(ctx context.Context) *Client {
 	return nil
 }
 
-func NewWithContext(ctx context.Context) context.Context {
+func NewWithContext(ctx context.Context, config *Configuration) (context.Context, error) {
-	client := ctx.Value(contextKey)
+	client, err := NewClient(config)
-	if client == nil {
+	if err != nil {
-		return ctx
+		return nil, errors.New("failed to create client: " + err.Error())
 	}
 
-	if c, ok := client.(*Client); ok {
+	ctx = context.WithValue(ctx, contextKey, client)
-		return context.WithValue(ctx, contextKey, c)
+	if c, ok := ctx.Value(contextKey).(*Client); ok {
+		return context.WithValue(ctx, contextKey, c), nil
+	} else {
+		return nil, errors.New("failed to set client in context")
 	}
-
-	return ctx
 }

client/token.go

@@ -3,6 +3,7 @@ package client
 import (
 	"bytes"
 	"encoding/json"
+	"errors"
 	"gitea.siteworxpro.com/golang-packages/email-api-client/redis"
 	"net/http"
 	"time"
@@ -47,6 +48,10 @@ func getToken(configuration *Configuration) (*Token, error) {
 		return nil, err
 	}
 
+	if resp.StatusCode != http.StatusOK || resp.ContentLength <= 0 {
+		return nil, errors.New("Failed to retrieve access token: " + resp.Status)
+	}
+
 	responseBody := make([]byte, resp.ContentLength)
 	_, err = resp.Body.Read(responseBody)
 	if err != nil {