Imprimatur is a tool for performing automated functional testing on web applications. The tests are described in a simple test script. Along with the standard HTTP methods, Imprimatur handles authentication, file uploads and HTTPS. The responses are validated using regular expressions.

Imprimatur runs on Python 2.7 and 3.4 on both CPython and PyPy.

See the GitHub repository for code, bugs, feature requests etc.


It’s a good idea to set up a virtualenv:

virtualenv venv
. venv/bin/activate

then install Imprimatur with pip:

pip install imprimatur

Upgrading from Java version

There’s a converter in the form of an XSL stylesheet which will transform the old style XML scripts to the new style Python ones. Download the stylesheet and save it in the same directory as the the XML file. Edit your XML file to point to the stylesheet, so the first two lines of the XML document look like:

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="convert.xsl"?>

Also, remove any <test-group> elements and make sure all <request> elements are within <test> elements. Then open the XML file in a browser and copy and paste the page into a new file. The name attribute of <imprimatur> won’t be carried over into the new file.


To run an example test script save the following as a file called

    'host': '',
    'status_code': 200}]

then run it with:


and it should come back saying all tests are passed. Here’s another script with some more examples:

        'name': "Single regex",
        'port': 5000,
        'host': "localhost",
        'path': "/text_2",
        'status_code': 200,
        'regexes': ['inexhaustible']},
        'name': "Basic auth",
        'path': "/auth",
        'auth': ("conrad", "kurtz"),
        'status_code': 200},
        'name': "File upload",
        'path': "/echo",
        'method': "post",
        'files': {"yellow": "tests/2/crome-file.txt"},
        'regexes': ["yellow", "on the leads"],
        'status_code': 200},
        'name': "Post name and value with regex.",
        'path': "/echo",
        'method': "post",
        'data': {"quote": "Leisure is the mother of philosophy."},
        'status_code': 200,
        'regexes': ["Leisure"]},
        'name': "Repeat until successful.",
        'path': "/counter",
        # 'max' is maximum number of times to try
        # 'period' is the number of seconds to wait between tries
        'tries': {'max': 3, 'period': 1},
        'status_code': 200,
        'regexes': ["The Decline And Fall Of The Roman Empire"]},
        'name': "Regex on header.",
        'path': "/redirect?location=http://localhost:5000/here.html",
        'status_code': 302,
        'regexes': ["here.html"]},
        'name': "HTTP HEAD request.",
        'path': "/text_1",
        'method': "head",
        'status_code': 200}]


The full list of properties for each request is given below. A * after the property name means that it is carried over to subsequent requests.

Name Notes


Can be 'http' (default) or 'https'.


Default is 'localhost'.


Default is 80.


Sequence of username and password eg. ('conrad', 'kurtz')


For an HTTPS request, verify the certificate. Can be True or False (default).


Used to label the request.


End of the URL eg. '/retrieve?product_id=45'. Default is '/'.


An HTTP method. eg. 'post'. Default is 'get'.


Dictionary of post values eg. {'id': 45, 'name': 'agnez'}


File name and path to upload. Eg. {'yellow': 'crome.txt'}


Maximum number of times to try the URL. Eg. {'max': 5, 'period': 2}. The max value is the number of times to try, and the period is the number of seconds to wait between tries. If max is omitted it defaults to 10 and if period is omitted it defaults to 1, so {} is equivalent to {'max': 10, 'period': 1}.


Sequence of regular expressions eg. [r'go\s*ths', r'vandals']


HTTP status code to check for, eg. 200


Dictionary of HTTP headers eg. {'Accept-Charset': 'utf-8'}

Cookies are always retained between requests.

Web Interface

Imprimatur comes with a very basic web interface. You can try it out using Imprimatur’s built-in web server by doing:

python -m imprimatur.web

Don’t run it on a public facing production web server, as it is entirely unsecure.

Release Notes

Version 0.23.20, 2016-07-21

  • In the absence of a character encoding in the response, rather than guess assume utf-8 and ignore any errors.

Version 0.23.19, 2016-07-07

  • Fixed bug with custom HTTP headers.

Version 0.23.18, 2016-07-03

  • Added support for specifying HTTP headers.

Version 0.23.17, 2016-05-09

  • Fixed a bug where if a URL is malformed the test is skipped whereas it should fail.

Version 0.23.16, 2015-06-11

  • Now holds a session across requests.

Version 0.23.15, 2015-05-20

  • Fixes a bug where if there’s no body to a response, and it has to be printed out, then fails.

Version 0.23.14, 2015-02-19

  • Make sure templates directory is included in the distribution.

Version 0.23.13, 2015-02-15

  • Added the verify flag for controlling whether to verify SSL certificates or not. Can be True or False, the default is False.

Version 0.23.11, 2015-02-10

  • Include templates directory in the distribution, this is necessary for the web server.

  • A list of runs is now shown on the home page.

  • Give a good error message if there’s a syntax error in the script.

  • The wheel format distribution if Imprimatur now has the universal flag set which denotes that it runs on Python 2 and 3.

Version 0.23.10, 2015-02-03

  • Fixed bug where regex pattern wasn’t searching the headers.

  • Added the re.DOTALL flag so that a . in regular expressions matches line ending characters.

  • Added a rudimentary web interface.

Version 0.23.9, 2015-01-31

  • Various improvements to the converter from old style XML test scripts to new style ones.

  • Renamed the tries attribute number to max as it’s a better description of what it does.

  • Fixed bug where Imprimatur always retried max times, even when a request was successful.

Version 0.23.8, 2015-01-26

  • The converter from old style XML test scripts to new style ones now carries over the comments as well.

Version 0.23.7, 2015-01-25

  • Added a converter to convert from old style XML test scripts to new style Python ones.

Version 0.23.5, 2015-01-22

  • The status_code attribute is now allowed to be either a str or an int. Previously it could only be an int.

  • The Passed all tests! message at the end is now followed by a newline character.

  • The auth attribute is now carried over from previous requests so that it doesn’t have to be specified explicitly in each subsequent request.

Version 0.23.4, 2015-01-21

  • Imprimatur now requires version 2.5.1 of the requests library. It was found that old versions of requests didn’t work.

  • Fixed a bug where the status code check isn’t working.

  • Added in a check for extraneous keys in the test script.

  • Included a lot more examples in the docs.

Version 0.23.3, 2015-01-19

  • Fixed various problems with Python 3.

Version 0.23.2, 2015-01-18

  • Added make sure dependencies (flask and requests) are automatically installed.

Version 0.23.1, 2015-01-18

  • Added imprimatur as a command-line script that is automatically installed.

Version 0.23.0, 2015-01-17

  • Ported to Python.

  • Moved to GitHub.

  • Has the same features as before, but the script format is no longer an XML file, but evaluatable Python.

  • Can be used as a Python library.

Version 22

  • Removed <session> element.

Version 20

  • Added support for HTTP HEAD requests.

Version 18

  • Gets don’t follow redirects by default.

  • Fixed example given in tests directory.

  • If no arguments are given on the command line, throws an exception saying no file specified.

Version 17

  • Can now set a request to follow redirects.

Version 15

  • Changed so that a regex matches if it’s found anywhere within the string.

  • In regexes, a dot character now matches line terminators as well.