Module goose::logger

Optional debug logger thread.

The Goose debug logger is enabled with the --debug-file command-line option, or the GooseDefault::DebugFile default configuration option. When enabled, this thread is launched and a channel is provided from all GooseUser threads to send debug information for efficient logging to file. The debug logger thread uses Tokio’s asynchronous BufWriter.

Writing Debug Logs

Logs can be sent to the logger thread by invoking log_debug from load test task functions.

Calls to set_failure automatically invoke log_debug.

Most of the included examples showing how to use the debug logger include a copy of the request made, the response headers returned by the server, and the response body. It can also be used to log arbitrary information, for example if you want to record everything you sent via a POST to a form.

use goose::prelude::*;

let mut task = task!(post_to_form);

async fn post_to_form(user: &GooseUser) -> GooseTaskResult {
    let path = "/path/to/form";
    let params = [
     ("field_1", "foo"),
     ("field_2", "bar"),
     ("op", "Save"),
    ];

    // Only log the form parameters we will post.
    user.log_debug(
        &format!("POSTing {:?} on {}", &params, path),
        None,
        None,
        None,
    )?;

    let request_builder = user.goose_post(path).await?;
    let goose = user.goose_send(request_builder.form(&params), None).await?;

    // Log the form parameters that were posted together with details about the entire
    // request that was sent to the server.
    user.log_debug(
        &format!("POSTing {:#?} on {}", &params, path),
        Some(&goose.request),
        None,
        None,
    )?;

    Ok(())
}

The first call to log_debug results in a debug log message similar to:

{"body":null,"header":null,"request":null,"tag":"POSTing [(\"field_1\", \"foo\"), (\"field_2\", \"bar\"), (\"op\", \"Save\")] on /path/to/form"}

The second call to log_debug results in a debug log message similar to:

{"body":null,"header":null,"request":{"elapsed":1,"final_url":"http://local.dev/path/to/form","method":"POST","name":"(Anon) post to form","redirected":false,"response_time":22,"status_code":404,"success":false,"update":false,"url":"http://local.dev/path/to/form","user":0},"tag":"POSTing [(\"field_1\", \"foo\"), (\"field_2\", \"bar\"), (\"op\", \"Save\")] on /path/to/form"}

For a more complex debug logging example, refer to the log_debug documentation.

Reducing File And Memory Usage

The debug logger can result in a very large debug file, as by default it includes the entire body of any pages returned that result in an error. This also requires allocating a bigger BufWriter, and can generate a lot of disk io.

If you don’t need to log response bodies, you can disable this functionality (and reduce the amount of RAM required by the BufWriter by setting the --no-debug-body command-line option, or the GooseDefault::NoDebugBody default configuration option. The debug logger will still record any custom messages, details about the request (when available), and all server response headers (when available).

Functions

logger_main

Logger thread, opens a log file (if configured) and waits for messages from GooseUser threads. This function is not intended to be invoked manually.