Integrate Notification Service into Tender Management System

- Added a new notification service to handle various notification types (email, SMS, push, OTP). - Implemented configuration for the notification service, allowing customization via environment variables. - Updated user and customer services to utilize the notification service for sending welcome emails and status updates. - Introduced a builder pattern for constructing notification requests, enhancing usability and flexibility. - Enhanced error handling and logging for notification operations, ensuring robust service integration. - Updated documentation to include usage examples and configuration details for the new notification SDK.
2025-09-16 15:35:36 +03:30
parent 05a307e345
commit 108629278a
15 changed files with 1429 additions and 21 deletions
@@ -0,0 +1,210 @@
+package notification
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"time"
+)
+
+// HTTPClient defines the interface for HTTP operations
+type HTTPClient interface {
+	Do(req *http.Request) (*http.Response, error)
+}
+
+// Client represents the notification service HTTP client
+type Client struct {
+	config     *Config
+	httpClient HTTPClient
+	logger     Logger
+}
+
+// Logger interface for structured logging
+type Logger interface {
+	Info(msg string, fields map[string]interface{})
+	Error(msg string, fields map[string]interface{})
+	Debug(msg string, fields map[string]interface{})
+	Warn(msg string, fields map[string]interface{})
+}
+
+// NewClient creates a new notification client
+func NewClient(config *Config, logger Logger) (*Client, error) {
+	if config == nil {
+		config = DefaultConfig()
+	}
+
+	if err := config.Validate(); err != nil {
+		return nil, fmt.Errorf("invalid configuration: %w", err)
+	}
+
+	httpClient := &http.Client{
+		Timeout: config.Timeout,
+	}
+
+	return &Client{
+		config:     config,
+		httpClient: httpClient,
+		logger:     logger,
+	}, nil
+}
+
+// NewClientWithHTTPClient creates a new notification client with custom HTTP client
+func NewClientWithHTTPClient(config *Config, httpClient HTTPClient, logger Logger) (*Client, error) {
+	if config == nil {
+		config = DefaultConfig()
+	}
+
+	if err := config.Validate(); err != nil {
+		return nil, fmt.Errorf("invalid configuration: %w", err)
+	}
+
+	return &Client{
+		config:     config,
+		httpClient: httpClient,
+		logger:     logger,
+	}, nil
+}
+
+// SendNotification sends a notification request to the notification service
+func (c *Client) SendNotification(ctx context.Context, req *NotificationRequest) (*NotificationResponse, error) {
+	// Validate request
+	if err := req.Validate(); err != nil {
+		return nil, fmt.Errorf("request validation failed: %w", err)
+	}
+
+	var lastErr error
+	start := time.Now()
+
+	for attempt := 0; attempt <= c.config.RetryAttempts; attempt++ {
+		if c.config.EnableLogging && c.logger != nil {
+			c.logger.Debug("Sending notification request", map[string]interface{}{
+				"attempt":    attempt + 1,
+				"event_type": req.EventType,
+				"user_id":    req.UserID,
+				"base_url":   c.config.BaseURL,
+			})
+		}
+
+		response, err := c.sendRequest(ctx, req)
+		if err == nil {
+			if c.config.EnableLogging && c.logger != nil {
+				c.logger.Info("Notification sent successfully", map[string]interface{}{
+					"event_type":   req.EventType,
+					"user_id":      req.UserID,
+					"attempts":     attempt + 1,
+					"elapsed_time": time.Since(start).String(),
+				})
+			}
+			return response, nil
+		}
+
+		lastErr = err
+
+		// Log retry attempt
+		if c.config.EnableLogging && c.logger != nil {
+			c.logger.Warn("Notification attempt failed", map[string]interface{}{
+				"attempt":    attempt + 1,
+				"error":      err.Error(),
+				"event_type": req.EventType,
+				"user_id":    req.UserID,
+			})
+		}
+
+		// Don't retry on certain errors
+		if !c.shouldRetry(err) {
+			break
+		}
+
+		// Don't sleep on last attempt
+		if attempt < c.config.RetryAttempts {
+			select {
+			case <-ctx.Done():
+				return nil, ctx.Err()
+			case <-time.After(c.config.RetryDelay):
+				// Continue to next attempt
+			}
+		}
+	}
+
+	if c.config.EnableLogging && c.logger != nil {
+		c.logger.Error("All notification attempts failed", map[string]interface{}{
+			"attempts":     c.config.RetryAttempts + 1,
+			"elapsed_time": time.Since(start).String(),
+			"last_error":   lastErr.Error(),
+			"event_type":   req.EventType,
+			"user_id":      req.UserID,
+		})
+	}
+
+	return nil, ErrRetryExhausted{
+		Attempts:    c.config.RetryAttempts + 1,
+		LastError:   lastErr,
+		ElapsedTime: time.Since(start).String(),
+	}
+}
+
+// sendRequest performs the actual HTTP request
+func (c *Client) sendRequest(ctx context.Context, req *NotificationRequest) (*NotificationResponse, error) {
+	// Marshal request body
+	requestBody, err := json.Marshal(req)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal request: %w", err)
+	}
+
+	// Create HTTP request
+	url := fmt.Sprintf("%s/api/v1/notifications", c.config.BaseURL)
+	httpReq, err := http.NewRequestWithContext(ctx, "POST", url, bytes.NewBuffer(requestBody))
+	if err != nil {
+		return nil, fmt.Errorf("failed to create HTTP request: %w", err)
+	}
+
+	// Set headers
+	httpReq.Header.Set("Content-Type", "application/json")
+	httpReq.Header.Set("User-Agent", c.config.UserAgent)
+
+	// Send request
+	resp, err := c.httpClient.Do(httpReq)
+	if err != nil {
+		return nil, fmt.Errorf("HTTP request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	// Read response body
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read response body: %w", err)
+	}
+
+	// Handle non-2xx status codes
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		// Try to parse error response
+		var errorResp NotificationErrorResponse
+		if json.Unmarshal(body, &errorResp) == nil && errorResp.Error != "" {
+			return nil, MapHTTPError(resp.StatusCode, errorResp.Error)
+		}
+		return nil, MapHTTPError(resp.StatusCode, string(body))
+	}
+
+	// Parse success response
+	var notificationResp NotificationResponse
+	if err := json.Unmarshal(body, &notificationResp); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal response: %w", err)
+	}
+
+	return &notificationResp, nil
+}
+
+// shouldRetry determines if a request should be retried based on the error
+func (c *Client) shouldRetry(err error) bool {
+	switch e := err.(type) {
+	case ErrHTTP:
+		// Retry on server errors (5xx) and certain client errors
+		return e.StatusCode >= 500 || e.StatusCode == http.StatusTooManyRequests
+	default:
+		// Retry on network errors, timeouts, etc.
+		return true
+	}
+}