review suggestions

pkg/gofr/datasource/mongo/mongo.go

@@ -40,7 +40,12 @@ type Config struct {
 
 const defaultTimeout = 5 * time.Second
 
-var errStatusDown = errors.New("status down")
+var (
+	errStatusDown   = errors.New("status down")
+	errMissingField = errors.New("missing required field in config")
+	errIncorrectURI = errors.New("incorrect URI for mongo")
+	errParseHost    = errors.New("failed to parse host from MongoDB URI")
+)
 
 /*
 Developer Note: We could have accepted logger and metrics as part of the factory function `New`, but when mongo driver is
@@ -84,25 +89,14 @@ func (c *Client) UseTracer(tracer any) {
 
 // Connect establishes a connection to MongoDB and registers metrics using the provided configuration when the client was Created.
 func (c *Client) Connect() {
-	var host string
+	uri, host, err := generateMongoURI(c.config)
+	if err != nil {
+		c.logger.Errorf("error generating mongo URI: %v", err)
+		return
+	}
 
 	c.logger.Debugf("connecting to MongoDB at %v to database %v", c.config.Host, c.config.Database)
 
-	uri := c.config.URI
-
-	if uri == "" {
-		uri = fmt.Sprintf("mongodb://%s:%s@%s:%d/%s?authSource=admin",
-			c.config.User, c.config.Password, c.config.Host, c.config.Port, c.config.Database)
-
-		host = c.config.Host
-	} else {
-		host = getDBHost(uri)
-
-		if host == "" {
-			c.logger.Debug("failed to parse URI: incorrect format provided")
-		}
-	}
-
 	timeout := c.config.ConnectionTimeout
 	if timeout == 0 {
 		timeout = defaultTimeout
@@ -133,13 +127,46 @@ func (c *Client) Connect() {
 	c.logger.Logf("connected to MongoDB at %v to database %v", host, c.Database)
 }
 
-func getDBHost(uri string) (host string) {
+func generateMongoURI(config *Config) (uri, host string, err error) {
+	if config.URI != "" {
+		host, err = getDBHost(config.URI)
+		if err != nil || host == "" {
+			return "", "", err
+		}
+
+		return config.URI, host, nil
+	}
+
+	switch {
+	case config.Host == "":
+		return "", "", fmt.Errorf("%w: host is empty", errMissingField)
+	case config.Port == 0:
+		return "", "", fmt.Errorf("%w: port is empty", errMissingField)
+	case config.Database == "":
+		return "", "", fmt.Errorf("%w: database is empty", errMissingField)
+	}
+
+	uri = fmt.Sprintf("mongodb://%s:%s@%s:%d/%s?authSource=admin",
+		config.User, config.Password, config.Host, config.Port, config.Database)
+
+	return uri, config.Host, nil
+}
+
+func getDBHost(uri string) (host string, err error) {
 	parsedURL, err := url.Parse(uri)
 	if err != nil {
-		return ""
+		return "", err
+	}
+
+	if parsedURL.Scheme != "mongodb" {
+		return "", errIncorrectURI
+	}
+
+	if parsedURL.Hostname() == "" {
+		return "", errParseHost
 	}
 
-	return parsedURL.Hostname()
+	return parsedURL.Hostname(), nil
 }
 
 // InsertOne inserts a single document into the specified collection.

pkg/gofr/datasource/mongo/mongo_test.go

@@ -36,43 +36,141 @@ func Test_NewMongoClient(t *testing.T) {
 	assert.NotNil(t, client)
 }
 
+func TestGenerateMongoURI(t *testing.T) {
+	tests := []struct {
+		name          string
+		config        Config
+		expectedURI   string
+		expectedHost  string
+		expectedError string
+	}{
+		{
+			name: "Valid Config",
+			config: Config{
+				User:     "admin",
+				Password: "password",
+				Host:     "localhost",
+				Port:     27017,
+				Database: "mydb",
+			},
+			expectedURI:   "mongodb://admin:password@localhost:27017/mydb?authSource=admin",
+			expectedHost:  "localhost",
+			expectedError: "",
+		},
+		{
+			name: "Predefined URI",
+			config: Config{
+				URI: "mongodb://admin:password@localhost:27017/mydb?authSource=admin",
+			},
+			expectedURI:   "mongodb://admin:password@localhost:27017/mydb?authSource=admin",
+			expectedHost:  "localhost",
+			expectedError: "",
+		},
+		{
+			name: "Empty Host",
+			config: Config{
+				User:     "admin",
+				Password: "password",
+				Port:     27017,
+				Database: "mydb",
+			},
+			expectedURI:   "",
+			expectedHost:  "",
+			expectedError: "missing required field in config: host is empty",
+		},
+		{
+			name: "Invalid Port",
+			config: Config{
+				User:     "admin",
+				Password: "password",
+				Host:     "localhost",
+				Database: "mydb",
+			},
+			expectedURI:   "",
+			expectedHost:  "",
+			expectedError: "missing required field in config: port is empty",
+		},
+		{
+			name: "Empty Database",
+			config: Config{
+				User:     "admin",
+				Password: "password",
+				Host:     "localhost",
+				Port:     27017,
+			},
+			expectedURI:   "",
+			expectedHost:  "",
+			expectedError: "missing required field in config: database is empty",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			client := Client{config: &test.config}
+			uri, host, err := generateMongoURI(client.config)
+
+			assert.Equal(t, test.expectedURI, uri, "Unexpected URI")
+			assert.Equal(t, test.expectedHost, host, "Unexpected Host")
+
+			if test.expectedError != "" {
+				assert.EqualError(t, err, test.expectedError, "Unexpected error message")
+			} else {
+				assert.NoError(t, err, "Expected no error but got one")
+			}
+		})
+	}
+}
+
 func TestGetDBHost(t *testing.T) {
 	tests := []struct {
-		name     string
-		uri      string
-		expected string
+		name        string
+		uri         string
+		expected    string
+		expectedErr string
 	}{
 		{
-			name:     "Valid URI with host and port",
-			uri:      "mongodb://username:password@hostname:27017/database?authSource=admin",
-			expected: "hostname",
+			name:        "Valid URI with host and port",
+			uri:         "mongodb://username:password@hostname:27017/database?authSource=admin",
+			expected:    "hostname",
+			expectedErr: "",
 		},
 		{
-			name:     "Valid URI with IP address as host",
-			uri:      "mongodb://username:[email protected]:27017/database?authSource=admin",
-			expected: "192.168.1.1",
+			name:        "Valid URI with IP address as host",
+			uri:         "mongodb://username:[email protected]:27017/database?authSource=admin",
+			expected:    "192.168.1.1",
+			expectedErr: "",
 		},
 		{
-			name:     "Invalid URI with no host",
-			uri:      "mongodb://username:password@:27017/database?authSource=admin",
-			expected: "",
+			name:        "Invalid URI with no host",
+			uri:         "mongodb://username:password@:27017/database?authSource=admin",
+			expected:    "",
+			expectedErr: "failed to parse host from MongoDB URI",
 		},
 		{
-			name:     "Empty URI",
-			uri:      "",
-			expected: "",
+			name:        "Empty URI",
+			uri:         "",
+			expected:    "",
+			expectedErr: "incorrect URI for mongo",
 		},
 		{
-			name:     "Malformed URI",
-			uri:      "mongodb:/username:password@hostname:27017/database?authSource=admin",
-			expected: "",
+			name:        "Malformed URI",
+			uri:         "mongodb:/username:password@hostname:27017/database?authSource=admin",
+			expected:    "",
+			expectedErr: "failed to parse host from MongoDB URI",
 		},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			result := getDBHost(tt.uri)
-			assert.Equal(t, tt.expected, result, "Test case: %s", tt.name)
+			host, err := getDBHost(tt.uri)
+
+			assert.Equal(t, tt.expected, host, "Test case: %s", tt.name)
+
+			if tt.expectedErr == "" {
+				assert.NoError(t, err, "Test case: %s", tt.name)
+			} else {
+				assert.EqualError(t, err, tt.expectedErr, "Test case: %s", tt.name)
+			}
 		})
 	}
 }