Critical Error at Agent Startup Due to Missing retry_interval_secs Key in Default Configuration

[vikman90]

Parent Issue: #241

Description

When starting the Wazuh Agent with the default configuration file (etc/config/wazuh-agent.yml), the following critical error is encountered:

[2024-11-11 10:14:06.941] [wazuh-agent] [critical] [CRITICAL] [main.cpp:67] [main] An error occurred: Key not found: retry_interval_secs.

The agent should be able to operate with its default configuration out of the box. Furthermore, if certain options are not specified in the configuration file, the agent should be able to apply default values instead of failing with an error.

Expected Behavior

• The agent should start successfully using the default configuration without requiring additional keys.
• Missing keys in the configuration file, such as retry_interval_secs, should be handled by applying predefined default values.

Steps to Reproduce

Start the Wazuh Agent with the default etc/config/wazuh-agent.yml configuration:

./wazuh-agent --config-file ../etc/config/wazuh-agent.yml --run

Proposed Solution

1. Implement a mechanism for handling missing configuration keys by applying default values.
2. Ensure that the retry_interval_secs key (and any other essential keys) have sensible defaults within the agent's codebase to prevent startup errors.

[aritosteles]

Update

• 2024/11/11:
  Getting to know yaml-cpp library. Evaluating different approaches.

• 2024/11/12 and 13:

  • Default value parameter was added to ConfigurationParser::GetConfig()
  • GetConfig() does not throw an exception if requested key is not found, default value returned instead
  • Modified config.cmake and config.h.in to allow configuration settings to be set on build
  • Updated all occurrences of GetConfig() in main code and in tests

• 2024/11/14:

  • Modified interface to avoid passing the default values all the way down to the configuration_parser and back. Made ConfigurationParser::GetConfig() to return an optional value. Updated all corresponding occurrencies.
  • PR up for final review.

[aritosteles]

Summary

• New ConfigurationParser::GetConfig() signature:

template<typename T, typename... Keys>
        std::optional<T> GetConfig(Keys... keys) const

• Usage example:

m_enabled = configurationParser.GetConfig<bool>( "inventory",
                                 enabled").value_or(config::inventory::DEFAULT_ENABLED);