Configuration
Explore how to manage test settings with OpenHTF's configuration module using in-code definitions or external configuration files.
Last updated · Verified with OpenHTF 1.6.1
Control test execution parameters with configuration variables or files.
A configuration key is declared in code with a default value. A YAML file loaded at startup overrides the default, and a command-line flag overrides the file. Phases read the final value through the conf module.
- conf.declare("voltage_limit")default_value=5.05.0
- conf.load_from_filename(...)config.yaml: voltage_limit: 5.5
- --config-value voltage_limit=6.0command line
- phase_voltageconf.voltage_limit
Sometimes you need to change script parameters without modifying the script itself, like updating firmware versions or adjusting instrument ports between stations. OpenHTF simplifies this by using configuration files to manage these parameters.
File
You can load configurations from an external file written in YAML or JSON format. Passing --config-file config.yaml on the command line does the same without code (see CLI flags). For example:
firmware_path: 'path/to/firmware_v1.0.0.bin'Load the configuration file during execution script:
import openhtf as htf
from openhtf.util import configuration
# Declare the firmware_path key
configuration.CONF.declare("firmware_path")
# Load configuration from an external YAML file
with open("config.yaml", "r") as yamlfile:
configuration.CONF.load_from_file(yamlfile)
def flash_firmware(test):
firmware_path = configuration.CONF.firmware_path
print(f"Flashing firmware from: {firmware_path}")
def main():
test = htf.Test(flash_firmware)
test.execute(test_start=lambda: "SN1234")
if __name__ == "__main__":
main()Built-in keys
OpenHTF declares a few keys itself. Set them in the same file or with --config-value key=value:
station_idstrName of the test station written to every record. Default: the machine's hostname.
station_server_portintPort for the Operator UI. Default 0 picks a free port.
stop_on_first_failureboolSame switch as test.configure(stop_on_first_failure=True) — see Test Options.
allow_unset_measurementsboolIf True, a declared measurement that is never set does not fail the phase. Default False.
capture_sourceboolStore the source code of phases in the record's code_info. Default False.
frontend_throttle_sfloatMinimum seconds between Operator UI updates. Default 0.15.
station_discovery_address / _port / _ttlMulticast settings for the multi-station dashboard.
Run any test with --config-help to print every declared key with its description and default.
Advanced use cases
Variables
You can set configuration variables directly in the script.
import openhtf as htf
from openhtf.util import configuration
# Define firmware_path configuration
configuration.CONF.declare(
"firmware_path",
default_value="path/to/firmware_v1.0.0.bin",
description="Path to the firmware file",
)
def flash_firmware(test):
firmware_path = configuration.CONF.firmware_path
print(f"Flashing firmware from: {firmware_path}")
def main():
test = htf.Test(flash_firmware)
test.execute(test_start=lambda: "SN1234")
if __name__ == "__main__":
main()You can set the following parameters for each configuration variable in OpenHTF:
.namestrThe unique identifier for the configuration variable (must be in snake_case).
.default_valueAn optional value that serves as the default if no other value is provided.
.descriptionstrAn optional description explaining the purpose of the configuration variable.
Decorator
You can use the save_and_restore decorator to temporarily change a value during the function call, which is then restored.
In this example, you can also configure the variable after its declaration.
import openhtf as htf
from openhtf.util import configuration
configuration.CONF.declare("phase_variance")
configuration.CONF.load(phase_variance=4)
@configuration.CONF.save_and_restore(phase_variance=55) # Decorator
def phase_one(test):
phase_variance_to_print = configuration.CONF.phase_variance
print(f"Value during phase one: {phase_variance_to_print}")
def phase_two(test):
phase_variance_to_print = configuration.CONF.phase_variance
print(f"Value during phase two: {phase_variance_to_print}")
def main():
test = htf.Test(phase_one, phase_two)
test.execute(test_start=lambda: "SN1234")
if __name__ == "__main__":
main()Related
Logger
Explore how to configure logger options in OpenHTF to capture and manage log output during test execution with examples.
Test Options
Reference for test.configure() in OpenHTF — test name, stop_on_first_failure, failure_exceptions, default_dut_id, diagnosers and output_callbacks — plus Test.execute() arguments.
