Organize backend into product executable and shared Go modules

backend/shared/database/factory.go

@@ -0,0 +1,26 @@
+package db
+
+import (
+	mongoimpl "git.sendico.io/tech/sxchnge/shared/database/internal/mongo"
+	"git.sendico.io/tech/sxchnge/shared/database/transaction"
+	"git.sendico.io/tech/sxchnge/shared/errors"
+	"git.sendico.io/tech/sxchnge/shared/logging"
+)
+
+// Factory exposes the local connection and transaction lifecycle.
+type Factory interface {
+	TransactionFactory() transaction.Factory
+
+	CloseConnection()
+}
+
+// NewConnection builds a Factory backed by the configured driver.
+func NewConnection(logger mlogger.Logger, config *Config) (Factory, error) {
+	if config == nil {
+		return nil, merrors.InvalidArgument("database configuration is required", "config")
+	}
+	if config.Driver == Mongo {
+		return mongoimpl.NewConnection(logger, config.Settings)
+	}
+	return nil, merrors.InvalidArgument("unknown database driver: "+string(config.Driver), "config.driver")
+}