Taurus Configuration Syntax

Configuration dictionary has several top-level keys:

  • execution - main section, declares tools to be executed during run, scenarios to use, etc
  • reporting - analysis and reporting settings, list of reporting modules to process results
  • services - service modules configuration
  • scenarios - dictionary of scenario specifications with aliases, to be referred from executions
  • modules - list of classes to load and their respective settings
  • settings - some top-level settings for the tool
  • provisioning - advanced option, allows using resources other than local to have distributed high-load test, available if you have corresponding provider installed and configured
  • included-configs - this section allows merging additional config files

Example for config that touches all sections:

- concurrency: 10
  hold-for: 5m
  ramp-up: 2m
  scenario: sample
        Connection: close
    - http://localhost/

- module: final-stats
- module: console

    path: ./local/jmeter
        log_level: DEBUG
    disable: false
  check-interval: 5s
  default-executor: jmeter

provisioning: local

Multiple Files Merging Rules

The rules for merging multiple configuration files into single are following:

  1. Process starts with empty configuration structure {}
  2. Files are loaded one by one, every file must contain dictionary, either in YAML or in JSON format (+INI for command-line overrides)
  3. Loaded dictionary is merged recursively into configuration, dictionaries are merged and lists are joined.
  4. If dictionary key has ~ prefix, it will overwrite the value instead of merging
  5. If dictionary key has ^ prefix, it will delete the corresponding key/value pair
  6. If dictionary key has $ prefix and the value under that key is a list, it will perform element-wise merging of corresponding list items.
  7. If dictionary values has different type, e.g. string value vs array, the value will be overwritten and the warning message will be issued

Most configuration elements have their default values and also have some shorthand forms to specify trivial cases. We encourage users to learn these rules to speed up configuration files creation and make them short.

Important to know that merging happens before any default value or shorthand rules are processed, so you should use the same approach to express settings in all files. The most common case is execution branch, that can be either dictionary (key/value pairs) or array of dictionaries. Attempting to merge file containing array of executions with single-execution will lead to overwriting instead of appending array. For that case, have a practice to always use either array or dictionary in files that are being merged.

Modules Settings

The Module Settings section is a dictionary, having module aliases as keys and setting dictionaries as values. Module settings are specific to every module, the only common option is class, containing full python class name as value. Module aliases are used to refer from reporting settings, tool executors and many other places. In fact, everything in Taurus is implemented through modules and engine has no dependencies to specific module implementations, everything is config-driven.

The shorthand is to specify module class string instead of settings dictionary, Taurus will expand it into dict automatically. For example,

  final-stats: bzt.modules.reporting.FinalStatus

is equivalent to

    class: bzt.modules.reporting.FinalStatus

Top-Level Settings

Available settings are:

  • artifacts-dir - path template where to save artifact files, uses strftime template syntax
  • check-interval - polling interval that used by engine after startup and until shutdown to determine if test is need to be stopped
  • aggregator - module alias for top-level results aggregator to be used for collecting results and passing it to reporters
  • default-executor - module alias for executor that will be used by default for executions
  • ramp-up-exclude - exclude ramp-up data from cumulative stats
  • proxy - proxy settings for BZA feeding, Taurus will use proxy settings from OS environment by default.
  • env - environment variables to set for Taurus, useful with evaluating feature. Setting environment variable to null makes it to delete variable, if one is set. Special TAURUS_ARTIFACTS_DIR variable is set by Taurus, pointing onto artifacts dir location.

See default settings below:

  artifacts-dir: /tmp/%H%M%S # path where to save artifacts, default is %Y-%m-%d_%H-%M-%S.%f
  aggregator: consolidator
  default-executor: jmeter
  ramp-up-exclude: false
  check-interval: 1
  proxy:  # custom proxy settings
    address:  # proxy server address
    username: user  # username and password used if authentication is configured on proxy server
    password: 12345
    ssl-cert: path/to/cert  # SSL server-side certificate. You can set it to `false` to disable cert validation.
    ssl-client-cert: path/to/cert  # SSL client-side certificate
  check-updates: true  # check for newer version of Taurus on startup
  verbose: false  # whenever you run bzt with -v option, it sets debug=true, 
                  # some modules might use it for debug features,
                  # setting this through config also switches CLI verbosity
  env: # set environment variables, see below for more explanation

There is special handling in Taurus for env variable named TAURUS_DISABLE_DOWNLOADS. Setting it to any value will make Taurus to raise error instead of downloading any tool from Internet.

Environment Variable Access

Env variables that you specify under settings.env are replaced throughout config with ${varname} syntax. This helps with parameterizing config files, when you want to use same value throughout config file and control its value from single place.

Consider example config file:

    BASE_DIR: /home/theuser/bigproject
- scenario: ${BASE_DIR}/recorded.jmx

      CSV_PATH: ${BASE_DIR}/items.csv

Upon Taurus startup, it will be evaluated into:

- scenario: /home/theuser/bigproject/recorded.jmx

      CSV_PATH: /home/theuser/bigproject/items.csv

Now, you can change single value in config and have all corresponding places changed. For example, you can use parameter for command-line -o settings.env.BASEDIR=/tmp/experimentcheckout and have the value changed without modifications of YAML config.

Please note that mapping keys are not subject for variable evaluation, so you can't use ${varname} inside property name. Only string values of configuration items are processed.

Also remember that env variables are passed to all processes that Taurus spawn, so you can access these params from inside your custom scripts (JMX/Python/Java/JavaScript etc.)

Human-Readable Time Specifications

All time specifications in Taurus configs, including timeouts and durations, are always expressed in unit of seconds. Use special strings convention to make it human-readable. Examples:

  • 1s200ms = 1 second 200 milliseconds
  • 1d 2h 3m 4s = 93784 seconds

d - days, h - hours, m - minutes, s - seconds, ms - milliseconds, optional space characters allowed

If you have found config instruction that does not follow this rule, report immediately, this is most likely a bug.

YAML/JSON Format for Config Files

As you know, JSON is a subset of YAML. But in BZT config files there is no usage for YAML-JSON incompatibilities, so you can use either JSON or YAML for your configs. Also, you can have some configs in JSON and some in YAML, the engine will perfectly deal with it. For example, following JSON file:

  "execution": [
      "executor": "jmeter",
      "scenario": "sample"
  "scenarios": {
     "sample": {
       "script": "tests/jmx/dummy.jmx"
  "provisioning": "local",
  "aggregator": "aggregator",
  "reporting": [
      "module": "final-stats"
  "modules": {
    "jmeter": {
      "path": "build/jmeter/bin/jmeter",
      "class": "bzt.modules.jmeter.JMeterExecutor",
      "properties": {
        "jmeter.save.saveservice.autoflush": "true"

is equivalent to YAML:

aggregator: aggregator

- executor: jmeter
  scenario: jmx_sample
    script: tests/jmx/dummy.jmx
    class: bzt.modules.jmeter.JMeterExecutor
    path: build/jmeter/bin/jmeter
      jmeter.save.saveservice.autoflush: 'true'
provisioning: local

- module: status

Look for merged.yml/json and effective.yml/json file pairs in artifacts to see matching examples.

If you're not familiar with YAML, you can check out our YAML Tutorial.

Hint: YAML config files on Linux/macOS allows a trick of self-executing config. To have it, add shebang line as first line of your file, like this:

#! /usr/local/bin/bzt
- hold-for: 1m
  scenario: simple
     - http://blazedemo.com/

Then add execution flag to the file:

chmod +x myscript.yml

Now you are able to start this file on its own:

./myscript.yml -o execution.hold-for=5m

Included Configs

After all config files loaded, Taurus will also recursively merge into resulting configuration any included-configs from the list. Example syntax piece:

included-configs:  # it must be a list of string values
- additional-local-file.yml  # to add local file just set its path
- http://central.host/mystorage/remote.yml  # you can also download config from http/https location