Customize the Lightrun Python agent¶
According to the Lightrun actions you specify, the agent dynamically inserts logs and snapshots in the target environment. The agent's behavior when performing these tasks is governed by a set of user-configurable properties.
Agent properties¶
You can specify the agent properties within the code or by using a config file.
Specifying agent properties within the code¶
You set agent configuration properties by entering keyword arguments in the lightrun.enable() call function. For example:
lightrun.enable(server_url="https://mycompany.com/myserver", company_key="123456-abcde")
The server_url keyword is required only if Lightrun is used as an on-premise deployment.
Specifying agent properties using a config file¶
When using lightrun.enable, you can either pass the company_key parameter (as above), or use the agent_config parameter as shown in this example.
The agent_config keyword must reference the full path to a user-created agent.config file.
You can see this an example agent.config file. The default parameter values can be modified for your own applications.
Note
The above methods for passing keywords can be combined. However, configuration parameters passed as keyword arguments override the parameter values in agent.config (if provided).
Configuration parameters¶
The following table lists the configuration parameters that can be set in both the agent.config file and the lightrun.enable() call function.
| Flag name | Description | Default value |
|---|---|---|
company | Company name. | - |
server_url | The URL of the Lightrun backend server (default: https://app.lightrun.com/ should only be changed when using Lightrun on-premise. | - |
com_lightrun_server | Combined URL of of the company and the Lightrun backend server. This single parameter can be used instead of the combination of company and server_url. | - |
company_key | The company's secret API key. | - |
breakpoint_expiration_sec | The default expiration time for Lightrun actions. | - |
ignore_quota | Whether or not to disable all performance safety measures. Warning: Use with caution. | - |
agent_regmetadata_file | Path to a JSON file containing the agent's registration metadata (such as tags, and display name). | - |
metadata_registration_tags | Array of tags for the agent, can be used when there is no metadata file. You set agent tags by entering metadata_registration_tags argument in the lightrun.enable() call function. For example: lightrun.enable(company_key="<COMPANY_SECRET>", metadata_registration_tags='[{"name": "Production"},{"name": "EastUS"}]') | - |
dynamic_log_console_handler_format | The format for the logs to be printed by inserted logpoints to the console. For example: '%(levelname)s: %(message)s'. | - |
dynamic_log_file_handler_file_pattern | The pattern for writing logpoints to a file. If this parameter is left empty, logs from inserted actions are not written to a file. | - |
dynamic_log_file_handler_format | The format for logs from inserted log points to be printed to the file specified in the dynamic_log_file_handler_file_pattern | - |
base_dir | Files from this directory will have a higher priority in the case of name conflicts. | sys.path[0] |
lightrun_wait_for_init | Block the application until the first time breakpoints are fetched from the server. This option is intended for short-running applications like serverless functions, and it ensures that the Lightrun agent has time to communicate with the Lightrun server before the short-running application disconnects. Note: Using lightrun_wait_for_init in a cloud environment will likely incur additional costs from the cloud provider due to a longer application runtime. | False |
lightrun_init_wait_time_seconds | Timeout in seconds for wait if lightrun_wait_for_init is set. | - |
max_condition_cost | Maximum allowed additional CPU load when inserting actions during condition evaluation (value between 0.1 and 1.0). | 1.0 |
max_log_cpu_cost | Maximum allowed additional CPU load when logging (value between 0.1 and 1.0). | 1.0 |
max_snapshot_buffer_size max_snapshot_buffer_size_in_bytes | Maximum allowed total bytes for snapshots. Introduced in version 1.16, and replaces max_snapshot_buffer_size_in_bytes. Deprecation note: From version 1.16, This field is deprecated and replaced by max_snapshot_buffer_size. | 768000 32768 |
max_variable_size | Maximum snapshot variable string size. To retrieve large values, add them as watch expressions to a snapshot. Note: Introduced in version 1.16 | 256 |
max_watchlist_variable_size | Maximum size of all snapshot variables that were specified via watch expressions. Note: Introduced in version 1.16. Starting from version 1.53, a limit is applied to all variables. The limit is calculated as max_watchlist_variable_size divided by expressionCount. | 512KB |
max_collection_size | Controls the number of items captured for a collection. Note: Introduced in version 1.36. | 100 |
max_watchlist_collection_size | Controls the number of items captured for a collection in a watch expression. Note: Introduced in version 1.36. | 1024 |
max_frames_with_vars | Controls the number of top stack frames for which to read values of local variables. Note: Introduced in version 1.36. | 4 |
max_object_members | Controls the number of properties captured in an object. Note: Introduced in version 1.36. | 100 |
default_certificate_pinning_enabled | Enable/disable certificate pinning. Setting to false skips certificate checking. | True |
enable_pii_redaction | Enable personally identifiable information (PII) redaction at the agent's side (may affect the application's performance) | False |
alsologtostderr | Sends the logs to STDERR standard file as opposed to typically sending them over to STDOUT. | True |
agent_log_max_file_size_mb | Maximum size in MB that a log file can reach before being rotated. | 10 |
agent_log_max_file_count | Maximum number of rotated log files to keep. Note that old files get deleted when this number of log files is reached. | 5 |
agent_log_target_dir | Sets the target directory for storing agent logs, which defaults to the operating system's temporary folder. From version 1.34, the log filename will be generated automatically according to the format: lightrun_python_agent.<PID>.<TIMESTAMP>.<LOG_ROTATION_RUNNING_INDEX>.log. For example: lightrun_python_agent.22840.20240513-153557.1.log. | String |
agent_log_level | Minimum log level that is written to the log file. Available levels of severity, from the highest to lowest (not case sensitive): None, Fatal, Error, Warning, Info, Debug, and Verbose. | Info |
Info
Except for the parameter company_key, all other configuration options have default values.
HTTP-Proxy configuration¶
A custom HTTP proxy server can be configured for the agent traffic.
The proxy server should support the CONNECT method.
proxy_host and proxy_port are mandatory settings, and should be provided together.
When specifying proxy_host, provide it as host.com without a protocol (e.g., https://host.com or http://host.com should not be used).
| Property name | Environment variable | Description |
|---|---|---|
proxy_host | LIGHTRUN_PROXY_HOST | HTTP-proxy host. |
proxy_port | LIGHTRUN_PROXY_PORT | HTTP-proxy port. |
proxy_username | LIGHTRUN_PROXY_USERNAME | HTTP-proxy username (optional). |
proxy_password | LIGHTRUN_PROXY_PASSWORD | HTTP-proxy password (optional). |