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A drop in replacement for Django's built-in runserver command. Features include:

• An extendable interface for handling things such as real-time logging.
• Integration with the werkzeug interactive debugger.
• An improved runserver allowing you to process requests simultaneously.

To install the latest stable version:

pip install git+git://github.com/dcramer/django-devserver#egg=django-devserver

django-devserver has some optional dependancies, which we highly recommend installing.

• pip install sqlparse -- pretty SQL formatting
• pip install werkzeug -- interactive debugger
• pip install guppy -- tracks memory usage (required for MemoryUseModule)
• pip install line_profiler -- does line-by-line profiling (required for LineProfilerModule)

You will need to include devserver in your INSTALLED_APPS:

INSTALLED_APPS = (
    ...
    'devserver',
)

Specify modules to load via the DEVSERVER_MODULES setting:

DEVSERVER_MODULES = (
    'devserver.modules.sql.SQLRealTimeModule',
    'devserver.modules.sql.SQLSummaryModule',
    'devserver.modules.profile.ProfileSummaryModule',

    # Modules not enabled by default
    'devserver.modules.ajax.AjaxDumpModule',
    'devserver.modules.profile.MemoryUseModule',
    'devserver.modules.cache.CacheSummaryModule',
    'devserver.modules.profile.LineProfilerModule',
)

You may also specify prefixes to skip processing for. By default, ADMIN_MEDIA_PREFIX, MEDIA_URL and STATIC_URL (for Django >= 1.3) will be ignored (assuming MEDIA_URL and STATIC_URL is relative):

DEVSERVER_IGNORED_PREFIXES = ['/media', '/uploads']

Once installed, using the new runserver replacement is easy. You must specify verbosity of 0 to disable real-time log output:

python manage.py runserver

Note: This will force settings.DEBUG to True.

By default, devserver would bind itself to 127.0.0.1:8000. To change this default, DEVSERVER_DEFAULT_ADDR and DEVSERVER_DEFAULT_PORT settings are available.

Please see python manage.py runserver --help for additional options.

You may also use devserver's middleware outside of the management command:

MIDDLEWARE_CLASSES = (
        'devserver.middleware.DevServerMiddleware',
)

django-devserver includes several modules by default, but is also extendable by 3rd party modules.

Outputs queries as they happen to the terminal, including time taken.

Disable SQL query truncation (used in SQLRealTimeModule) with the DEVSERVER_TRUNCATE_SQL setting:

DEVSERVER_TRUNCATE_SQL = False

Outputs a summary of your SQL usage.

Outputs a summary of the request performance.

Outputs a notice when memory use is increased (at the end of a request cycle).

Profiles view methods on a line by line basis. There are 2 ways to profile your view functions, by setting setting.DEVSERVER_AUTO_PROFILE = True or by decorating the view functions you want profiled with devserver.modules.profile.devserver_profile. The decoration takes an optional argument follow which is a sequence of functions that are called by your view function that you would also like profiled.

An example of a decorated function:

@devserver_profile(follow=[foo, bar])
def home(request):
    result['foo'] = foo()
    result['bar'] = bar()

When using the decorator, we recommend that rather than import the decoration directly from devserver that you have code somewhere in your project like:

try:
    if 'devserver' not in settings.INSTALLED_APPS:
        raise ImportError
    from devserver.modules.profile import devserver_profile
except ImportError:
    class devserver_profile(object):
        def __init__(self, *args, **kwargs):
            pass
        def __call__(self, func):
            def nothing(*args, **kwargs):
                return func(*args, **kwargs)
            return wraps(func)(nothing)

By importing the decoration using this method, devserver_profile will be a pass through decoration if you aren't using devserver (eg in production)

Outputs a summary of your cache calls at the end of the request.

Outputs the content of any AJAX responses

Change the maximum response length to dump with the DEVSERVER_AJAX_CONTENT_LENGTH setting:

DEVSERVER_AJAX_CONTENT_LENGTH = 300

Outputs information about the current session and user.

Building modules in devserver is quite simple. In fact, it resembles the middleware API almost identically.

Let's take a sample module, which simple tells us when a request has started, and when it has finished:

from devserver.modules import DevServerModule

class UselessModule(DevServerModule):
    logger_name = 'useless'

    def process_request(self, request):
        self.logger.info('Request started')

    def process_response(self, request, response):
        self.logger.info('Request ended')

There are additional arguments which may be sent to logger methods, such as duration:

# duration is in milliseconds
self.logger.info('message', duration=13.134)