**How to Handle Errors During File Loading and Maintain Configuration State in a Go Application?**

Load data from reading files during startup and then process new files and clear old state from the map

This scenario involves loading data from files during server startup and storing it in a map. The code also monitors for new files periodically and updates the map with their data, replacing the previous state. However, an issue arises if an error occurs during file reading, as the map is cleared before the error is handled, leaving it empty.

To address this issue, a more straightforward approach can be employed:

Step 1: Load the initial configuration

Load the initial configuration from files during startup using a function that populates a CustomerConfig struct.

Step 2: Create a config cache

Create a ConfigCache struct that stores the current configuration (*CustomerConfig) and manages concurrent access using a sync.RWMutex. Additionally, create a closeCh channel to handle cache manager shutdown.

Step 3: Implement the config cache refresher

Launch a goroutine in refresher that periodically checks for changes. If changes are detected, it loads a new configuration using loadConfig and updates the cache with the new data. The method also monitors closeCh for shutdown requests.

Step 4: Provide a method to get the current configuration

Implement GetConfig to provide read-only access to the current *CustomerConfig. It uses sync.RWMutex for safe concurrent access.

Step 5: Manage the cache manager

Create the cache manager with NewConfigCache. To stop the refreshing, call Stop on the cache manager to close the closeCh.

Example usage:

<code class="go">// Create the config cache
cc, err := NewConfigCache()
if err != nil {
    // Handle error
}

// Get the current config
cfg := cc.GetConfig()

// Use the config in your application</code>

This revised approach ensures that if an error occurs during file reading, the previous configuration is preserved and remains accessible. It also simplifies the overall design while maintaining the desired functionality.

The above is the detailed content of **How to Handle Errors During File Loading and Maintain Configuration State in a Go Application?**. For more information, please follow other related articles on the PHP Chinese website!