pytest-play¶
pytest-play
is a codeless, generic, pluggable and extensible automation tool,
not necessarily test automation only, based on the fantastic pytest test framework
that let you define and execute YAML files containing scripts or test scenarios
through actions and assertions that can be implemented and managed even by non technical users:
automation (not necessarily test automation). You can build a set of actions on a single file (e.g, call a JSON based API endpoint, perform an action if a condition matches) or a test automation project with many test scenarios.
For example you can create always fresh test data on demand supporting manual testing activities, build a live simulator and so on
codeless, or better almost codeless. If you have to write assertions against action results or some conditional expressions you need a very basic knowledge of Python or Javascript expressions with a smooth learning curve (something like
variables['foo'] == 'bar'
)generic. It is not yet again another automation tool for browser automation only, API only, etc. You can drive a browser, perform some API calls, make database queries and/or make assertions using the same tool for different technologies
So there are several free or not free testing frameworks or automation tools and many times they address just one single area testing needs and they are not extensible: API testing only, UI testing only and so on. It could be fine if you are testing a web only application like a CMS but if you are dealing with a reactive IoT application you might something more, make cross actions or cross checks against different systems or build something of more complex upon
pytest-play
powerful. It is not yet again another test automation tool, it only extends the pytest framework with another paradigm and inherits a lot of good stuff (test data decoupled by test implementation that let you write once and executed many times the same scenario thanks to native parametrization support, reporting, integration with test management tools, many useful command line options, browsers and remote Selenium grids integration, etc)
pluggable and extensible. Let’s say you need to interact with a system not yet supported by a
pytest-play
plugin, you can write by your own or pay someone for you. In addition there is a scaffolding tool that let you implement your own command: https://github.com/davidemoro/cookiecutter-play-plugineasy to use. Why YAML? Easy to read, easy to write, simple and standard syntax, easy to be validated and no parentheses hell. Despite there are no recording tools (not yet) for browser interaction or API calls, the documentation based on very common patterns let you copy, paste and edit command by command with no pain
free software. It’s an open source project based on the large and friendly pytest community
easy to install. The only prerequisite is Docker thanks to the
davidemoro/pytest-play
Docker Hub container. Or better, with docker, no installation is required: you just need to type the following commanddocker run -i --rm -v $(pwd):/src davidemoro/pytest-play
inside your project folder See https://hub.docker.com/r/davidemoro/pytest-play
See at the bottom of the page the third party plugins that extends pytest-play
:
How it works¶
Depending on your needs and skills you can choose to use pytest-play programmatically writing some Python code or following a Python-less approach.
As said before with pytest-play you will be able to create codeless scripts or test scenarios
with no or very little Python knowledge: a file test_XXX.yml
(e.g., test_something.yml
,
where test_
and .yml
matter) will be automatically recognized and executed without having
to touch any *.py
module.
You can run a single scenario with pytest test_XXX.yml
or running the entire suite filtering
by name or keyword markers.
Despite pytest-play
was born with native support for JSON format, pytest-play
>=2.0 versions will support
YAML only for improved usability.
Python-less (pure YAML)¶
Here you can see the contents of a pytest-play
project without any Python files inside
containing a login scenario:
$ tree
.
├── env-ALPHA.yml (OPTIONAL)
└── test_login.yml
and you might have some global variables in a settings file specific for a target environment:
$ cat env-ALPHA.yml
pytest-play:
base_url: https://www.yoursite.com
The test scenario with action, assertions and optional metadata (play_selenium external plugin needed):
$ cat test_login.yml
---
markers:
- login
test_data:
- username: siteadmin
password: siteadmin
- username: editor
password: editor
- username: reader
password: reader
---
- comment: visit base url
type: get
provider: selenium
url: "$base_url"
- comment: click on login link
locator:
type: id
value: personaltools-login
type: clickElement
provider: selenium
- comment: provide a username
locator:
type: id
value: __ac_name
text: "$username"
type: setElementText
provider: selenium
- comment: provide a password
locator:
type: id
value: __ac_password
text: "$password"
type: setElementText
provider: selenium
- comment: click on login submit button
locator:
type: css
value: ".pattern-modal-buttons > input[name=submit]"
type: clickElement
provider: selenium
- comment: wait for page loaded
locator:
type: css
value: ".icon-user"
type: waitForElementVisible
provider: selenium
The first optional YAML document contains some metadata with keywords aka markers
so you can filter tests to be executed invoking pytest with marker expressions,
decoupled test data, etc.
The same test_login.yml
scenario will be executed 3 times with different
decoupled test data test_data
defined inside its first optional YAML
document (the block between the 2 ---
lines).
So write once and execute many times with different test data!
You can see a hello world example here:
As told before the metadata document is optional so you might have 1 or 2 documents in your YAML file. You can find more info about Metadata format.
Here you can see the same example without the metadata section for sake of completeness:
---
- comment: visit base url
type: get
provider: selenium
url: "http://YOURSITE"
- comment: click on login link
type: clickElement
provider: selenium
locator:
type: id
value: personaltools-login
- comment: provide a username
type: setElementText
provider: selenium
locator:
type: id
value: __ac_name
text: "YOURUSERNAME"
- comment: provide a password
type: setElementText
provider: selenium
locator:
type: id
value: __ac_password
text: "YOURPASSWORD"
- comment: click on login submit button
type: clickElement
provider: selenium
locator:
type: css
value: ".pattern-modal-buttons > input[name=submit]"
- comment: wait for page loaded
type: waitForElementVisible
provider: selenium
locator:
type: css
value: ".icon-user"
Programmatically¶
You can invoke pytest-play programmatically too.
You can define a test test_login.py
like this:
def test_login(play):
data = play.get_file_contents(
'my', 'path', 'etc', 'login.yml')
play.execute_raw(data, extra_variables={})
Or this programmatical approach might be used if you are
implementing BDD based tests using pytest-bdd
.
Core commands¶
pytest-play provides some core commands that let you:
- write simple Python assertions, expressions and variables
- reuse steps including other test scenario scripts
- provide a default command template for some particular providers (eg: add by default HTTP authentication headers for all requests)
- a generic wait until machinery. Useful for waiting for an observable asynchronous event will complete its flow before proceeding with the following commands that depends on the previous step completion
You can write restricted Python expressions and assertions based on the RestrictedPython
package.
RestrictedPython is a tool that helps to define a subset of the Python language which allows to provide a program input into a trusted environment. RestrictedPython is not a sandbox system or a secured environment, but it helps to define a trusted environment and execute untrusted code inside of it.
See:
How to reuse steps¶
You can split your commands and reuse them using the include
command avoiding
duplication:
- provider: include
type: include
path: "/some-path/included-scenario.yml"
You can create a variable for the base folder where your test scripts live.
Default commands¶
Some commands require many verbose options you don’t want to repeat (eg: authentication headers for play_requests).
Instead of replicating all the headers information you can initialize a pytest-play
with the provider name as
key and as a value the default command you want to omit (this example neets the external plugin play_selenium):
- provider: python
type: store_variable
name: bearer
expression: "'BEARER'"
- provider: python
type: store_variable
name: play_requests
expression: "{'parameters': {'headers': {'Authorization': '$bearer'}}}"
- provider: play_requests
type: GET
comment: this is an authenticated request!
url: "$base_url"
Store variables¶
You can store a pytest-play variables:
- provider: python
type: store_variable
expression: "1+1"
name: foo
Make a Python assertion¶
You can make an assertion based on a Python expression:
- provider: python
type: assert
expression: variables['foo'] == 2
Exec a Python expresssion¶
You can execute a Python expression:
- provider: python
type: exec
expression: "1+1"
While condition and looping¶
If you need to loop over a series of commands or wait something you can use
the while
command. It will execute the sequence of sub commands, if any,
while the resulting expression condition is true. Assuming you have a countdown
variable containing a integer 10
, the block of commands whill be executed 10 times:
---
- provider: python
type: while
expression: variables['countdown'] >= 0
timeout: 2.3
poll: 0.1
sub_commands:
- provider: python
type: store_variable
name: countdown
expression: variables['countdown'] - 1
The while
command supersedes the other legacy commands wait_until
(stops when the condition becomes true) or wait_until_not
.
commands.
Conditional commands (Python)¶
You can skip any command evaluating a Python based skip condition like the following:
- provider: include
type: include
path: "/some-path/assertions.yml"
skip_condition: variables['cassandra_assertions'] is True
How to assert commands elapsed time¶
The engine updates a pytest-play
variable called _elapsed
for each executed command. So you can write something that:
---
- type: GET
provider: play_requests
url: https://api.chucknorris.io/jokes/categories
expression: "'dev' in response.json()"
- type: assert
provider: python
expression: "variables['_elapsed'] > 0"
Generate a JUnit XML report¶
Use the --junit-xml
command line option, e.g.:
--junit-xml results.xml
You’ll get for each test case errors, commands executed in system-output
(do not use -s
or --capture=no
otherwise you won’t
see commands in system-output
) and execution timing metrics (global, per test case and per single command thanks to _elapsed
property tracked on every executed command shown in system-output
).
Here you can see a standard results.xml
file:
<?xml version="1.0" encoding="utf-8"?><testsuite errors="0" failures="0" name="pytest" skipped="0" tests="1" time="0.360"><testcase classname="test_assertion.yml" file="test_assertion.yml" name="test_assertion.yml" time="0.326"><system-out>{'expression': '1 == 1', 'provider': 'python', 'type': 'assert', '_elapsed': 0.0003077983856201172}
{'expression': '0 == 0', 'provider': 'python', 'type': 'assert', '_elapsed': 0.0002529621124267578}
</system-out></testcase></testsuite>
Generate a custom JUnit XML report with custom properties and execution times metrics¶
You can track execution time metrics for monitoring and measure what is important to you. For example you can track using a machine interpretable format:
- response times (e.g., how much time is needed for returning a
POST
json payload) - time that occurs between the invocation of an API and a reactive web application update or some asynchronous data appearing on an event store
- time that occurs between a user input on browser and results updated (e.g., a live search)
- time that occurs between a login button and the page loaded an usable (e.g., how much time is needed after a browser action to click on a target button)
Track response time metric in JUnit XML report¶
For example, a test_categories.yml
file executed with
the command line option --junit-xml report.xml
(requires play_requests plugin):
test_data:
- category: dev
- category: movie
- category: food
---
- type: GET
provider: play_requests
url: https://api.chucknorris.io/jokes/categories
expression: "'$category' in response.json()"
- provider: metrics
type: record_elapsed
name: categories_time
- type: assert
provider: python
expression: "variables['categories_time'] < 2.5"
comment: you can make an assertion against the categories_time
will generate an extended report.xml
file with custom properties like that:
<?xml version="1.0" encoding="utf-8"?><testsuite errors="0" failures="0" name="pytest" skipped="0" tests="3" time="2.031"><testcase classname="test_categories.yml" file="test_categories.yml" name="test_categories.yml0" time="0.968"><properties><property name="categories_time" value="0.5829994678497314"/></properties><system-out>{'expression': "'dev' in response.json()", 'provider': 'play_requests', 'type': 'GET', 'url': 'https://api.chucknorris.io/jokes/categories', '_elapsed': 0.5829994678497314}
{'name': 'categories_time', 'provider': 'metrics', 'type': 'record_elapsed', '_elapsed': 3.3855438232421875e-05}
{'comment': 'you can make an assertion against the categories_time', 'expression': "variables['categories_time'] < 2.5", 'provider': 'python', 'type': 'assert', '_elapsed': 0.0006382465362548828}
</system-out></testcase><testcase classname="test_categories.yml" file="test_categories.yml" name="test_categories.yml1" time="0.481"><properties><property name="categories_time" value="0.4184422492980957"/></properties><system-out>{'expression': "'movie' in response.json()", 'provider': 'play_requests', 'type': 'GET', 'url': 'https://api.chucknorris.io/jokes/categories', '_elapsed': 0.4184422492980957}
{'name': 'categories_time', 'provider': 'metrics', 'type': 'record_elapsed', '_elapsed': 2.09808349609375e-05}
{'comment': 'you can make an assertion against the categories_time', 'expression': "variables['categories_time'] < 2.5", 'provider': 'python', 'type': 'assert', '_elapsed': 0.000553131103515625}
</system-out></testcase><testcase classname="test_categories.yml" file="test_categories.yml" name="test_categories.yml2" time="0.534"><properties><property name="categories_time" value="0.463592529296875"/></properties><system-out>{'expression': "'food' in response.json()", 'provider': 'play_requests', 'type': 'GET', 'url': 'https://api.chucknorris.io/jokes/categories', '_elapsed': 0.463592529296875}
{'name': 'categories_time', 'provider': 'metrics', 'type': 'record_elapsed', '_elapsed': 2.09808349609375e-05}
{'comment': 'you can make an assertion against the categories_time', 'expression': "variables['categories_time'] < 2.5", 'provider': 'python', 'type': 'assert', '_elapsed': 0.00054931640625}
</system-out></testcase></testsuite>
and the custom property categories_time
will be tracked for each
test case execution, for example:
<properties>
<property name="categories_time" value="0.5829994678497314"/>
</properties>
Advanced metrics in JUnit XML report¶
In this example we want to measures how long it takes a page to become interactive
(page responding to user interactions) and evaluate update time for a live search feature.
Let’s see the test_search.yml
example (requires play_selenium):
---
- provider: selenium
type: get
url: https://www.plone-demo.info/
- provider: metrics
type: record_elapsed_start
name: load_time
- provider: selenium
type: setElementText
text: plone 5
locator:
type: id
value: searchGadget
- provider: metrics
type: record_elapsed_stop
name: load_time
- provider: metrics
type: record_elapsed_start
name: live_search_time
- provider: selenium
type: waitForElementVisible
locator:
type: css
value: li[data-url$="https://www.plone-demo.info/front-page"]
- provider: metrics
type: record_elapsed_stop
name: live_search_time
If you execute this scenario with the --junit-xml results.xml
option you’ll get a results.xml
file similar to this one:
<?xml version="1.0" encoding="utf-8"?><testsuite errors="0" failures="0" name="pytest" skipped="0" tests="1" time="13.650"><testcase classname="test_search.yml" file="test_search.yml" name="test_search.yml" time="13.580"><properties><property name="load_time" value="1.1175920963287354"/><property name="live_search_time" value="1.0871295928955078"/></properties><system-out>{'provider': 'selenium', 'type': 'get', 'url': 'https://www.plone-demo.info/', '_elapsed': 9.593282461166382}
{'name': 'load_time', 'provider': 'metrics', 'type': 'record_elapsed_start', '_elapsed': 1.1682510375976562e-05}
{'locator': {'type': 'id', 'value': 'searchGadget'}, 'provider': 'selenium', 'text': 'plone 5', 'type': 'setElementText', '_elapsed': 1.1019845008850098}
{'name': 'load_time', 'provider': 'metrics', 'type': 'record_elapsed_stop', '_elapsed': 1.9788742065429688e-05}
{'name': 'live_search_time', 'provider': 'metrics', 'type': 'record_elapsed_start', '_elapsed': 1.0013580322265625e-05}
{'locator': {'type': 'css', 'value': 'li[data-url$="https://www.plone-demo.info/front-page"]'}, 'provider': 'selenium', 'type': 'waitForElementVisible', '_elapsed': 1.060795545578003}
{'name': 'live_search_time', 'provider': 'metrics', 'type': 'record_elapsed_stop', '_elapsed': 2.3603439331054688e-05}
</system-out></testcase></testsuite>
and in this case you’ll find out that the key metric load_time
was 1.11
seconds and the live_search_time
was 1.09
seconds as
you can see here:
<properties>
<property name="load_time" value="1.1175920963287354"/>
<property name="live_search_time" value="1.0871295928955078"/>
</properties>
So thanks to JUnit XML reporting you can track response times (not only browser based timings) using a machine readable format to be ingested by third party systems with an acceptable approximation if you cannot track timings directly on the systems under test.
Track any property in JUnit XML reports using expressions¶
Let’s see a test_categories.yml
(play_selenium required):
test_data:
- category: dev
- category: movie
- category: food
---
- type: GET
provider: play_requests
url: https://api.chucknorris.io/jokes/categories
expression: "'$category' in response.json()"
- provider: metrics
type: record_property
name: categories_time
expression: "variables['_elapsed']*1000"
- type: assert
provider: python
expression: "variables['categories_time'] < 2500"
comment: you can make an assertion against the categories_time
generates some custom properties (categories_time
in milliseconds using a python expression)
using the --junit-xml results.xml
cli option:
<?xml version="1.0" encoding="utf-8"?><testsuite errors="0" failures="0" name="pytest" skipped="0" tests="3" time="2.312"><testcase classname="test_categories.yml" file="test_categories.yml" name="test_categories.yml0" time="1.034"><properties><property name="categories_time" value="610.3124618530273"/></properties><system-out>{'expression': "'dev' in response.json()", 'provider': 'play_requests', 'type': 'GET', 'url': 'https://api.chucknorris.io/jokes/categories', '_elapsed': 0.6103124618530273}
{'expression': "variables['_elapsed']*1000", 'provider': 'python', 'type': 'exec', '_elapsed': 0.0006859302520751953}
{'expression': "variables['_elapsed']*1000", 'name': 'categories_time', 'provider': 'metrics', 'type': 'record_property', '_elapsed': 0.006484270095825195}
{'comment': 'you can make an assertion against the categories_time', 'expression': "variables['categories_time'] < 2500", 'provider': 'python', 'type': 'assert', '_elapsed': 0.0005526542663574219}
</system-out></testcase><testcase classname="test_categories.yml" file="test_categories.yml" name="test_categories.yml1" time="0.550"><properties><property name="categories_time" value="443.72105598449707"/></properties><system-out>{'expression': "'movie' in response.json()", 'provider': 'play_requests', 'type': 'GET', 'url': 'https://api.chucknorris.io/jokes/categories', '_elapsed': 0.44372105598449707}
{'expression': "variables['_elapsed']*1000", 'provider': 'python', 'type': 'exec', '_elapsed': 0.0009415149688720703}
{'expression': "variables['_elapsed']*1000", 'name': 'categories_time', 'provider': 'metrics', 'type': 'record_property', '_elapsed': 0.01613616943359375}
{'comment': 'you can make an assertion against the categories_time', 'expression': "variables['categories_time'] < 2500", 'provider': 'python', 'type': 'assert', '_elapsed': 0.0011241436004638672}
</system-out></testcase><testcase classname="test_categories.yml" file="test_categories.yml" name="test_categories.yml2" time="0.676"><properties><property name="categories_time" value="576.5485763549805"/></properties><system-out>{'expression': "'food' in response.json()", 'provider': 'play_requests', 'type': 'GET', 'url': 'https://api.chucknorris.io/jokes/categories', '_elapsed': 0.5765485763549805}
{'expression': "variables['_elapsed']*1000", 'provider': 'python', 'type': 'exec', '_elapsed': 0.0006375312805175781}
{'expression': "variables['_elapsed']*1000", 'name': 'categories_time', 'provider': 'metrics', 'type': 'record_property', '_elapsed': 0.006584644317626953}
{'comment': 'you can make an assertion against the categories_time', 'expression': "variables['categories_time'] < 2500", 'provider': 'python', 'type': 'assert', '_elapsed': 0.0005452632904052734}
</system-out></testcase></testsuite>
obtaining the metrics you want to track for each execution, for example:
<properties><property name="categories_time" value="610.3124618530273"/></properties>
so you might track the category as well for each test execution or whatever you want.
Monitoring test metrics with statsd/graphite¶
If you like the measure everything approach you can track and monitor interesting custom test metrics from an end user perspective during normal test executions or heavy load/stress tests thanks to the statsd/graphite integration.
Measuring important key metrics is important for many reasons:
- compare performance between different versions under same conditions using past tracked stats for the same metric (no more say the system seems slower today)
- predict the system behaviour with many items on frontend (e.g., evaluate the browser dealing with thousands and thousands of items managed by an infinite scroll plugin)
- predict the system behaviour under load
You can install statsd
/graphite
in minutes using Docker:
Basically you can track on statsd
/graphite
every numeric metric using
the same commands used for tracking metrics on JUnit XML reports as we will see.
In addition, but not required, installing the third party plugin called pytest-statsd.
you can track on statsd
/graphite
:
- execution times
- number of executed tests per status (pass, fail, error, etc)
Prerequisites (you need to install the optional statsd client not installed by default)::
pip install pytest-play[statsd]
Usage (cli options compatible with pytest-statsd
):
--stats-d [--stats-prefix play --stats-host http://myserver.com --stats-port 3000]
where:
--stats-d
, enablestatsd
--stats-prefix
(optional), if you plan on having multiple projects sending results to the same server. For example if you provideplay
as prefix you’ll get a time metric under thestats.timers.play.YOURMETRIC.mean
key (or instead of.mean
you can use.upper
,upper_90
, etc)--stats-host
, by defaultlocalhost
--stats-port
, by default8125
Now you can track timing metrics using the record_elapsed
or
record_elapsed_start
/record_elapsed_stop
commands seen before (pytest-play will
send for you time values to statsd
converted to milliseconds
as requested by statsd
).
If you want to track custom metrics using the record_property
command you have to provide
an additional parameter called metric_type
. For example:
- provider: metrics
type: record_property
name: categories_time
expression: "variables['_elapsed']*1000"
metric_type: timing
- provider: metrics
type: record_property
name: fridge_temperature
expression: "4"
metric_type: gauge
Some additional information regarding the record_property
command:
- if you don’t provide the
metric_type
option inrecord_property
commands values will not be transmitted tostatsd
(eventually they will be tracked on JUnit XML report if--junit-xml
option was provided) - if you provide an allowed
metric_type
value (timing
orgauge
) non numeric values will be considered as an error (ValueError
exception raised) - non allowed
metric_type
values will be considered as an error - if you provide
timing
asmetric_type
, it’s up to you providing a numeric value expressed inmilliseconds
Monitor HTTP response times¶
Monitor API response time (see https://github.com/pytest-dev/pytest-play/tree/features/examples/statsd_graphite_monitoring):

Browser metrics¶
Monitor browser metrics using Selenium from an end user perspective (see https://github.com/pytest-dev/pytest-play/tree/features/examples/statsd_graphite_monitoring_selenium):
- from page load to page usable
- live search responsiveness

Record metrics programmatically¶
If you don’t want to use pytest-play
but you need to record test metrics
you can use pytest-play
as a library::
def test_programmatically(play):
play.execute_command({
'provider': 'metrics',
'type': 'record_property',
'name': 'oil_temperature',
'expression': '60',
'metric_type': 'gauge'})
Performance tests with pytest-play and bzt/Taurus (BlazeMeter)¶
You can reuse all your pytest-play scenario and turn them to performance tests using bzt/Taurus (so it is compatible with BlazeMeter too and all its goodies).
Add a bzt/Taurus YAML file with no test_
prefix like that (full example here in
bzt_performance):
settings:
artifacts-dir: /tmp/%Y-%m-%d_%H-%M-%S.%f
execution:
- executor: pytest
scenario: pytest-run
iterations: 1
scenarios:
pytest-run:
# additional-args: --stats-d --stats-prefix play
script: scripts/
services:
- module: shellexec
prepare:
- pip3 install -r https://raw.githubusercontent.com/davidemoro/pytest-play-docker/master/requirements.txt
and run the following command:
docker run --rm -it -v $(pwd):/src --user root --entrypoint "bzt" davidemoro/pytest-play bzt.yml
You will see bzt up and running playing our scenarios:

You can uncomment additional-args
to pass other pytest
command line options (e.g., enable statsd
for key user metrics monitoring or any other cli option).
More info about bzt/Taurus here:
Dynamic expressions in payloads without declaring variables¶
If you have to send a certain payload to a REST endpoint or a MQTT message
containing a dynamic value you can store a variable with store_variable
and use $variable_name
in your payload when needed.
Storing variables is cool if you will reuse later that value but if just have to
generate a dynamic value, let’s say a timestamp in milliseconds,
you can use the {! EXPRESSION !}
format.
For example (play_mqtt plugin required):
---
- comment: python expressions in mqtt payload (without declaring variables)
provider: mqtt
type: publish
host: "$mqtt_host"
port: "$mqtt_port"
endpoint: "$mqtt_endpoint/$device_serial_number"
payload: '{
"measure_id": [124],
"obj_id_L": [0],
"measureType": ["float"],
"start_time": {! int(datetime.datetime.utcnow().timestamp()*1000) !},
"bin_value": [1]
}'
where instead of the expression:
{! int(datetime.datetime.utcnow().timestamp()*1000) !},
will be printed:
1553007973702
Browser based commands¶
The pytest-play
core no more includes browser based commands. Moved to play_selenium
external plugin.
pytest-play is pluggable and extensible¶
pytest-play
has a pluggable architecture and you can extend it.
For example you might want to support your own commands, support non UI commands like making raw POST/GET/etc calls, simulate IoT devices activities, provide easy interaction with complex UI widgets like calendar widgets, send commands to a device using the serial port implementing a binary protocol and so on.
How to register a new command provider¶
Let’s suppose you want to extend pytest-play with the following command:
command = {'type': 'print', 'provider': 'newprovider', 'message': 'Hello, World!'}
You just have to implement a command provider:
from pytest_play.providers import BaseProvider
class NewProvider(BaseProvider):
def this_is_not_a_command(self):
""" Commands should be command_ prefixed """
def command_print(self, command):
print(command['message'])
def command_yetAnotherCommand(self, command):
print(command)
and register your new provider in your setup.py
adding an entrypoint:
entry_points={
'playcommands': [
'print = your_package.providers:NewProvider',
],
},
You can define new providers also for non UI commands. For example publish MQTT messages simulating IoT device activities for integration tests.
If you want you can generate a new command provider thanks to:
Metadata format¶
You can also add some scenario metadata placing another YAML document on top of the scenario
defined on the test_XXX.yml
with the following format:
---
markers:
- marker1
- marker2
test_data:
- username: foo
- username: bar
---
# omitted scenario steps in this example...
Option details:
markers
, you can decorate your scenario with one or more markers. You can use them in pytest command line for filtering scenarios to be executed thanks to marker expressions like-m "marker1 and not slow"
test_data
, enables parametrization of your decoupletd test data and let you execute the same scenario many times. For example the example above will be executed twice (one time with “foo” username and another time with “bar”)
New options will be added in the next feature (e.g., skip scenarios, xfail, xpass, etc).
Examples¶
Articles and talks¶
Articles:
- Hello pytest-play!
- API/REST testing like Chuck Norris with pytest play using YAML
- pytest-play automated docker hub publishing workflow
- Test automation framework thoughts and examples with Python, pytest and Jenkins
Talks:
Third party pytest-play plugins¶
play_selenium,
pytest-play
plugin driving browsers using Selenium/Splinter under the hood. Selenium grid compatible and implicit auto wait actions for more robust scenarios with less controls.play_requests,
pytest-play
plugin driving the famous Pythonrequests
library for makingHTTP
calls.play_sql,
pytest-play
support for SQL expressions and assertionsplay_cassandra,
pytest-play
support for Cassandra expressions and assertionsplay_dynamodb,
pytest-play
support for AWS DynamoDB queries and assertionsplay_websocket,
pytest-play
support for websocketsplay_mqtt,
pytest-play
plugin for MQTT support. Thanks toplay_mqtt
you can test the integration between a mocked IoT device that sends commands on MQTT and a reactive web application with UI checks.You can also build a simulator that generates messages for you.
Feel free to add your own public plugins with a pull request!
Welcome to pytest-play’s documentation!¶
Contents:
Changelog¶
2.3.0 (2019-04-05)¶
Features and improvements:
wait_until
andwait_until_not
now accept commands with nosub_commands
property- implement new
while
command in python provider (while expression is true)
2.2.2 (2019-03-29)¶
Minor changes:
- remove internal property parameter on engine
Bugfix:
- add compatibility with
pytest-repeat
’s--count
command line option
Documentation:
- mention how to generate dynamic values using
{! expr !}
expressions (e.g., dynamic payloads in REST or MQTT without having to store variables when not needed)
2.2.1 (2019-03-19)¶
Minor changes:
- add
int
andfloat
builtins available in Python expressions - make python expressions more flexible for future improvements (internal change that doesn’t affect compatibility)
Bugfix:
- fix
--setup-plan
invokation
Documentation:
- add more examples (bzt/Taurus and performance tests using pytest-play)
2.2.0 (2019-03-01)¶
statsd
integration (optional requirement) for advanced test metrics using statsd/graphite. If you install pytest play with the optional statsd support withpytest-play[statsd]
you will get the additional dependencystatsd
client and you can use the same cli options defined by thepytest-statsd
plugin (e.g.,--stats-d [--stats-prefix myproject --stats-host http://myserver.com --stats-port 3000]
).Note well: despite the above cli options are the same defined by the
pytest-statsd
plugin, at this time of writingpytest-statsd
is not apytest-play
dependency so you won’t get stats about number of failures, passing, etc but only stats tracked bypytest-play
. If you need them you can installpytest-statsd
(it plays well withpytest-play
)
2.1.0 (2019-02-22)¶
Features:
support junit xml generation file with
system-out
element for each test case execution (pytest--junit-xml
option).system-out
will tracked by default in junit report unless you use the--capture=no
or its alias-s
track
_elapsed
time for each executed command--junit-xml
report ifsystem-out
is enabledtrack
pytest
custom properties in--junit-xml
report for monitoring and measure what is important to you. For example you can track as key metric the time of the time occurred between the end of the previous action and the completion of the following. Basically you can track under theproperty_name
load_login key the time occurred between the click on the submit button and the end of the current command (e.g., click on the menu or text input being able to receive text) using a machine interpretable format.The
property_name
value elapsed time will be available as standardpytest-play
variable so that you can make additional assertionsafter every command execution a
pytest-play
variable will be added/updated reporting the elapsed time (accessible usingvariables['_elapsed']
).So be aware that the
_elapsed
variable name should be considered as a special variable and so you should not use this name for storing variablesimprove debug in case of failed assertions or errored commands. Logged variables dump in standard logs and
system-out
reporting if availableimprove debuggability in case of assertion errors (log failing expression)
added a new
metrics
provider that let you track custom metrics in conjunction with--junit-xml
option. You can track in a machine readable format response times, dynamic custom expressions, time that occurs between different commands (e.g., measure the time needed after a login to interact with the page, time before an asynchronous update happens and so on). Under themetrics
provider you’ll find therecord_property
,record_elapsed
,record_elapsed_start
andrecord_elapsed_stop
commands
Documentation:
- minor documentation changes
- add more examples
2.0.2 (2019-02-06)¶
Documentation:
- more examples
- fix documentation bug on README (example based on selenium with missing
provider: selenium
)
2.0.1 (2019-01-30)¶
Documentation:
- Mention davidemoro/pytest-play docker container in README.
You can use pytest-play with a docker command like that now
docker run -i --rm -v $(pwd):/src davidemoro/pytest-play
Bugfix:
- Fix error locking pipenv due to pytest-play requirement constraint not existing (RestrictedPython>=4.0.b2 -> RestrictedPython>=4.0b2)
2.0.0 (2019-01-25)¶
Breaking changes:
- Renamed fixture from play_json to play (#5)
- Drop json support, adopt yaml only format for scenarios (#5)
- Drop
.ini
file for metadata, if you need them you can add a YAML document on top of the scenario.yml
file. You no more need multiple files for decorating your scenarios now (#65) - play.execute no more accepts raw data string), consumes a list of commands. Introduced play.execute_raw accepting raw data string.
- play.execute_command accepts a Python dictionary only now (not a string)
- Selenium provider removed from
pytest-play
core, implemented on a separate packageplay_selenium
. Starting from now you have to add to your selenium commandsprovider: selenium
- engine’s
parametrizer_class
attribute no more available ( useparametrizer.Parametrizer
by default now)
Bug fix:
- Fix invalid markup on PyPI (#55)
- Fix invalid escape sequences (#62).
Documentation and trivial changes:
- Add examples folder
1.4.2 (2018-05-17)¶
- Configuration change on Github. Use the same branching policy adopted by pytest (master becomes main branch, see #56)
- Fixed skipped test and added new tests (deselect scenarios with keyword and marker expressions)
- Fix #58: you no more get a TypeError if you try to launch pytest-play in autodiscovery mode
- Fix #55: restructured text lint on README.rst (bad visualization on pypi)
- Updated README (articles and talks links)
- Added a
DeprecationWarning
for play_json fixture. pytest-play will be based on yaml instead of json in version >=2.0.0. See https://github.com/pytest-dev/pytest-play/issues/5
1.4.1 (2018-04-06)¶
- Documentation improvements
- Add bzt/Taurus/BlazeMeter compatibility
1.4.0 (2018-04-05)¶
Small documentation improvements
Now
test_XXX.json
files are automatically collected and executedYou can run a test scenario using the pytest CLI
pytest test_YYY.json
Introduced json test scenario ini file with markers definition. For a given
test_YYY.json
scenario you can add atest_YYY.ini
ini file:[pytest] markers = marker1 marker2
and filter scenarios using marker expressions
pytest -m marker1
Enabled parametrization of arguments for a plain json scenario in scenario ini file:
[pytest] test_data = {"username": "foo"} {"username": "bar"}
and your json scenario will be executed twice
pytest-play
loads some variables based on the contents of the optionalpytest-play
section in yourpytest-variables
file now. So if your variables file contains the following values:pytest-play: foo: bar date_format: YYYYMMDD
you will be able to use expressions
$foo
,$date_format
,variables['foo']
orvariables['date_format']
1.3.2 (2018-02-05)¶
- Add
sorted
in python expressions
1.3.1 (2018-01-31)¶
- Add more tests
- Documentation update
- play_json fixture no more assumes that you have some pytest-variables settings. No more mandatory
- fix include scenario bug that occurs only on Windows (slash vs backslash and JSON decoding issues)
1.3.0 (2018-01-22)¶
- documentation improvements
- supports teardown callbacks
1.2.0 (2018-01-22)¶
implement python based commands in
pytest-play
and deprecatesplay_python
. So this feature is a drop-in replacement for theplay-python
plugin.You should no more install
play_python
since now.update documentation
deprecate selenium commands (they will be implemented on a separate plugin and dropped in
pytest-play
>= 2.0.0). All your previous scripts will work fine, this warning is just for people directly importing the provider for some reason.implement skip conditions. You can omit the execution of any command evaluating a Python based skip condition
1.1.0 (2018-01-16)¶
- Documentation updated (add new pytest play plugins)
- Support default payloads for command providers. Useful for HTTP authentication headers, common database settings
1.0.0 (2018-01-10)¶
- execute command accepts kwargs now
- execute command returns the command value now
- complete refactor of
include
provider (no backwards compatibility) - add
play_json.get_file_contents
and removeddata_getter
fixture (no backwards compatibility)
0.3.1 (2018-01-04)¶
- play engine now logs commands to be executed and errors
0.3.0 (2018-01-04)¶
- you are able to update variables when executing commands
- you can extend
pytest-play
with new pluggable commands coming from third party packages thanks to setuptools entrypoints
0.2.0 (2018-01-02)¶
no more open browser by default pytest-play is a generic test engine and it could be used for non UI tests too.
So there is no need to open the browser for non UI tests (eg: API tests)
0.1.0 (2017-12-22)¶
- implement reusable steps (include scenario)
- minor documentation changes
0.0.1 (2017-12-20)¶
- First release
API¶
Here you can see the technical documentation.
pytest_play.plugin¶
-
class
pytest_play.plugin.
YAMLFile
(fspath, parent=None, config=None, session=None, nodeid=None)[source]¶
-
class
pytest_play.plugin.
YAMLItem
(name, parent=None, config=None, session=None, nodeid=None, callspec=None, keywords=None, originalname=None)[source]¶ -
module
¶ Needed for Taurus/bzt/BlazeMeter compatibility See https://bit.ly/2GE2KS4
-