You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: path_config_connection.go
    path of file: ./repos/vault/builtin/logical/rabbitmq
    
    the code of the file until where you have to start completion: // Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: BUSL-1.1

package rabbitmq

import (
	"context"
	"fmt"

	"github.com/hashicorp/vault/sdk/framework"
	"github.com/hashicorp/vault/sdk/helper/template"
	"github.com/hashicorp/vault
    
func readConfig(ctx context.Context, storage logical.Storage) (connectionConfig, error) {
	entry, err := storage.Get(ctx, storageKey)
	if err != nil {
		return connectionConfig{}, err
	}
	if entry == nil {
		return connectionConfig{}, nil
	}

	var connConfig connectionConfig
	if err := entry.DecodeJSON(&connConfig); err != nil {
		return connectionConfig{}, err
	}
	return connConfig, nil
}