WebKit.DebugAppServer | index /usr/local/share/webware/WebKit/DebugAppServer.py

`DebugAppServer
`DebugAppServer` executes all requests within the main thread, allowing
servlets to be easily debugged using any Python debugger. The drawback is
that only one request can be processed at a time using this approach.
Also, exceptions are not caught and gracefully handled with an HTML error
page. Instead, the exceptions rise uncaught which allows the debugger to
trap them so you can inspect the program.
To use, simply run "python Launch.py DebugAppServer" using whatever debugging
environment you prefer.
Caveats:
This app server supports the AutoReload feature but not for Python's standard
modules or WebKit or WebKit's dependencies (MiscUtils, WebUtils and TaskKit).
Even with that limitation, auto-reload is still useful because if you modify
any module in your site, the auto-reload will happen. Note that the app server
*will* restart when the aformentioned modules are modified, but the modules
won't actually be reloaded.
Currently the session sweeper is still run within a separate thread, and
a "close thread" is started up by the AppServer base class, but neither
of these two extra threads should pose any problems debugging servlets.
Tested on:
- WingIDE on Windows, http://wingware.com/
- PythonWin
- JEdit with the JPyDbg plugin, on Windows`

Modules

``

WebKit.Profiler | WebKit.ThreadedAppServer | sys |

Classes

``

WebKit.Application.Application(WebKit.ConfigurableForServerSidePath.ConfigurableForServerSidePath)
  DebugApplication
WebKit.ThreadedAppServer.ThreadedAppServer(WebKit.AutoReloadingAppServer.AutoReloadingAppServer)
  DebugAppServer
__builtin__.object
  DummyRequestQueue

class DebugAppServer(WebKit.ThreadedAppServer.ThreadedAppServer)
`` | `Single-threaded AppServer for debugging purposes. We are piggybacking on 99% of the code in ThreadedAppServer. Our trick is to replace the request queue with a dummy object that executes requests immediately instead of pushing them onto a queue to be handled by other threads.`

Method resolution order:
  DebugAppServer
  WebKit.ThreadedAppServer.ThreadedAppServer
  WebKit.AutoReloadingAppServer.AutoReloadingAppServer
  WebKit.AppServer.AppServer
  WebKit.ConfigurableForServerSidePath.ConfigurableForServerSidePath
  MiscUtils.Configurable.Configurable
  __builtin__.object

Methods defined here:

__init__(self, path=None)
  `Initialize DebugAppServer.`

config(self)
  `Return default configuration.`

createApplication(self)
  `Create and return an application object. Invoked by __init__.`

mainloop(self)
  `Main loop for Windows.
  This is needed for COM support on Windows, because special thread
  initialization is required on any thread that runs servlets, in
  this case the main thread itself.`

restart(self)

Methods inherited from WebKit.ThreadedAppServer.ThreadedAppServer:

abortLongRequests(self)
  `Check for long-running requests and cancel these.
  The longest allowed execution time for requests is controlled
  by the MaxRequestTime setting.`

abortRequest(self, requestID, exception=<class 'WebKit.ThreadedAppServer.RequestAbortedError'>)
  `Abort a request by raising an exception in its worker thread.
  A return value of one means the thread was successfully aborted,
  a value of zero means the thread could not be found,
  any other value indicates that an error has occurred.`

absorbThread(self, count=1)
  `Absorb a thread.
  We do this by putting a None on the Queue.
  When a thread gets it, that tells it to exit.
  We also keep track of the threads, so after killing
  threads we go through all the threads and find the
  thread(s) that have exited, so that we can take them
  out of the thread pool.`

activeThreadCount(self)
  `Get a snapshot of the number of threads currently in use.
  Called from `updateThreadUsage`.`

addSocketHandler(self, handlerClass, serverAddress=None)
  `Add socket handler.
  Adds a socket handler for `serverAddress` -- `serverAddress`
  is a tuple ``(host, port)``, where ``host`` is the interface
  to connect to (for instance, the IP address on a machine with
  multiple IP numbers), and ``port`` is the port (e.g. HTTP is on
  80 by default, and Webware adapters use 8086 by default).
  The `handlerClass` is a subclass of `Handler`, and is used to
  handle the actual request -- usually returning control back
  to ThreadedAppServer in some fashion. See `Handler` for more.`

address(self, settingPrefix)
  `Get host address.
  The address for the Adapter (Host/interface, and port),
  as taken from ``Configs/AppServer.config``,
  settings ``Host`` and ``AdapterPort``.`

addressFileName(self, handlerClass)
  `Get the name of the text file with the server address.`

awakeSelect(self)
  `Awake the select() call.
  The `select()` in `mainloop()` is blocking, so when
  we shut down we have to make a connect to unblock it.
  Here's where we do that.`

defaultConfig(self)
  `The default AppServer.config.`

delThread(self)
  `Delete thread.
  Invoked immediately by threadloop() as a hook for subclasses.
  This implementation does nothing and subclasses need not invoke super.`

initThread(self)
  `Initialize thread.
  Invoked immediately by threadloop() as a hook for subclasses.
  This implementation does nothing and subclasses need not invoke super.`

isPersistent(self)

manageThreadCount(self)
  `Adjust the number of threads in use.
  From information gleened from `updateThreadUsage`, we see about how
  many threads are being used, to see if we have too many threads or
  too few. Based on this we create or absorb threads.`

shutDown(self)
  `Called on shutdown.
  Also calls `AppServer.shutDown`, but first closes all sockets
  and tells all the threads to die.`

spawnThread(self)
  `Create a new worker thread.
  Worker threads poll with the `threadloop` method.`

threadloop(self)
  `The main loop for worker threads.
  Worker threads poll the `_requestQueue` to find a request handler
  waiting to run. If they find a None in the queue, this thread has
  been selected to die, which is the way the loop ends.
  The handler object does all the work when its `handleRequest` method
  is called.
  `initThread` and `delThread` methods are called at the beginning and
  end of the thread loop, but they aren't being used for anything
  (future use as a hook).`

updateThreadUsage(self)
  `Update the threadUseCounter list.
  Called periodically from `mainloop`.`

Data and other attributes inherited from WebKit.ThreadedAppServer.ThreadedAppServer:

e = 'EPROTO'

Methods inherited from WebKit.AutoReloadingAppServer.AutoReloadingAppServer:

activateAutoReload(self)
  `Start the monitor thread.`

deactivateAutoReload(self)
  `Stop the monitor thread.`

fileMonitorThreadLoop(self)
  `This the the main loop for the monitoring thread.
  Runs in its own thread, polling the files for changes directly
  (i.e., going through every file that's being used and checking
  its last-modified time, seeing if it's been changed since it
  was initially loaded).`

fileMonitorThreadLoopFAM(self)
  `Monitoring thread loop, but using the FAM library.`

monitorNewModule(self, filepath, mtime=None)
  `Add new file to be monitored.
  This is a callback which ImportSpy invokes to notify us of new files
  to monitor. This is only used when we are using FAM.`

restartIfNecessary(self)
  `Check if the app server should be restarted.
  This should be called regularly to see if a restart is required.
  The server can only restart from the main thread, other threads
  can't do the restart. So this polls to see if `shouldRestart`
  has been called.`

shouldRestart(self)
  `Tell the main thread to restart the server.`

Methods inherited from WebKit.AppServer.AppServer:

application(self)
  `Return the Application singleton.`

checkForInstall(self)
  `Check whether Webware was installed.
  Exits with an error message if Webware was not installed.
  Called from `__init__`.`

closeThread(self)
  `This method is called when the shutdown sequence is initiated.`

configFilename(self)
  `Return the name of the AppServer configuration file.`

configReplacementValues(self)
  `Get config values that need to be escaped.`

initiateShutdown(self)
  `Ask the master thread to begin the shutdown.`

loadPlugIn(self, path)
  `Load and return the given plug-in.
  May return None if loading was unsuccessful (in which case this method
  prints a message saying so). Used by `loadPlugIns` (note the **s**).`

loadPlugIns(self)
  `Load all plug-ins.
  A plug-in allows you to extend the functionality of WebKit without
  necessarily having to modify its source. Plug-ins are loaded by
  AppServer at startup time, just before listening for requests.
  See the docs in `WebKit.PlugIn` for more info.`

numRequests(self)
  `Return the number of requests.
  Returns the number of requests received by this app server
  since it was launched.`

plugIn(self, name, default=<class 'MiscUtils.NoDefault'>)
  `Return the plug-in with the given name.`

plugIns(self)
  `Return a list of the plug-ins loaded by the app server.
  Each plug-in is a Python package.`

printStartUpMessage(self)
  `Invoked by __init__, prints a little intro.`

readyForRequests(self)
  `Declare ready for getting requests.
  Should be invoked by subclasses when they are finally ready to
  accept requests. Records some stats and prints a message.`

recordPID(self)
  `Save the pid of the AppServer to a file.`

serverSidePath(self, path=None)
  `Return the absolute server-side path of the WebKit app server.
  If the optional path is passed in, then it is joined with the
  server side directory to form a path relative to the app server.`

startTime(self)
  `Return the time the app server was started.
  The time is given as seconds, like time().`

version(self)
  `Return WebKit version.`

webKitPath(self)
  `Return teh WebKit path.`

webwarePath(self)
  `Return the Webware path.`

Methods inherited from WebKit.ConfigurableForServerSidePath.ConfigurableForServerSidePath:

setting(self, name, default=<class 'MiscUtils.NoDefault'>)
  `Return setting, using the server side path when indicated.
  Returns the setting, filtered by serverSidePath(),
  if the name ends with ``Filename`` or ``Dir``.`

Methods inherited from MiscUtils.Configurable.Configurable:

commandLineConfig(self)
  `Return the settings that came from the command-line.
  These settings come via addCommandLineSetting().`

configName(self)
  `Return the name of the configuration file without the extension.
  This is the portion of the config file name before the '.config'.
  This is used on the command-line.`

hasSetting(self, name)
  `Check whether a configuration setting has been changed.`

printConfig(self, dest=None)
  `Print the configuration to the given destination.
  The default destination is stdout. A fixed with font is assumed
  for aligning the values to start at the same column.`

setSetting(self, name, value)
  `Set a particular configuration setting.`

userConfig(self)
  `Return the user config overrides.
  These settings can be found in the optional config file.
  Returns {} if there is no such file.
  The config filename is taken from configFilename().`

Data descriptors inherited from MiscUtils.Configurable.Configurable:

__dict__
  `dictionary for instance variables (if defined)`

__weakref__
  `list of weak references to the object (if defined)`

class DebugApplication(WebKit.Application.Application)
`` | `This is a modified Application class for debugging.`

Method resolution order:
  DebugApplication
  WebKit.Application.Application
  WebKit.ConfigurableForServerSidePath.ConfigurableForServerSidePath
  MiscUtils.Configurable.Configurable
  __builtin__.object

Methods defined here:

handleException(self)
  `Handle exception.
  This should only be used in cases where there is no transaction object,
  for example if an exception occurs when attempting to save a session
  to disk.`

handleExceptionInTransaction(self, excInfo, transaction)
  `Handle exception with info.
  Raises exception `excInfo` (as returned by ``sys.exc_info()``)
  that was generated by `transaction`.`

Methods inherited from WebKit.Application.Application:

__init__(self, server, useSessionSweeper=True)
  `Called only by `AppServer`, sets up the Application.`

addContext(self, name, path)
  `Add a context by named `name`, rooted at `path`.
  This gets imported as a package, and the last directory
  of `path` does not have to match the context name.
  (The package will be named `name`, regardless of `path`).
  Delegated to `URLParser.ContextParser`.`

addShutDownHandler(self, func)
  `Add a shutdown handler.
  Functions added through `addShutDownHandler` will be called when
  the AppServer is shutting down. You can use this hook to close
  database connections, clean up resources, save data to disk, etc.`

callMethodOfServlet(self, trans, url, method, *args, **kw)
  `Call method of another servlet.
  Call a method of the servlet referred to by the URL. Calls sleep()
  and awake() before and after the method call. Or, if the servlet
  defines it, then `runMethodForTransaction` is used (analogous to the
  use of `runTransaction` in `forward`).
  The entire process is similar to `forward`, except that instead of
  `respond`, `method` is called (`method` should be a string, `*args`
  and `**kw` are passed as arguments to that method).`

configFilename(self)

configReplacementValues(self)

contexts(self)
  `Return a dictionary of context-name: context-path.`

createSessionForTransaction(self, trans)
  `Get the session object for the transaction.
  If the session already exists, returns that, otherwise creates
  a new session.
  Finding the session ID is done in `Transaction.sessionId`.`

createSessionWithID(self, trans, sessionID)
  `Create a session object with our session ID.`

defaultConfig(self)
  `The default Application.config.`

dispatchRawRequest(self, requestDict, strmOut)
  `Dispatch a raw request.
  Dispatch a request as passed from the Adapter through the AppServer.
  This method creates the request, response, and transaction object,
  then runs (via `runTransaction`) the transaction. It also catches any
  exceptions, which are then passed on to `handleExceptionInTransaction`.`

errorPage(self, errorClass)
  `Get the error page url corresponding to an error class.`

forward(self, trans, url)
  `Forward the request to a different (internal) URL.
  The transaction's URL is changed to point to the new servlet,
  and the transaction is simply run again.
  Output is _not_ accumulated, so if the original servlet had any output,
  the new output will _replace_ the old output.
  You can change the request in place to control the servlet you are
  forwarding to -- using methods like `HTTPRequest.setField`.`

handleMissingPathSession(self, trans)
  `Redirect requests without session info in the path.
  If UseAutomaticPathSessions is enabled in Application.config
  we redirect the browser to an absolute url with SID in path
  http://gandalf/a/_SID_=2001080221301877755/Examples/
  _SID_ is extracted and removed from path in HTTPRequest.py
  This is for convinient building of webapps that must not
  depend on cookie support.
  Note that we create an absolute URL with scheme and hostname
  because otherwise IIS will only cause an internal redirect.`

handlePathSession(self, trans)
  `Handle the session identifier that has been found in the path.`

handleUnnecessaryPathSession(self, trans)
  `Redirect request with unnecessary session info in the path.
  This is called if it has been determined that the request has a path
  session, but also cookies. In that case we redirect to eliminate the
  unnecessary path session.`

hasContext(self, name)
  `Checks whether context `name` exist.`

hasSession(self, sessionId)
  `Check whether session `sessionId` exists.`

includeURL(self, trans, url)
  `Include another servlet.
  Include the servlet given by the URL. Like `forward`,
  except control is ultimately returned to the servlet.`

initErrorPage(self)
  `Initialize the error page related attributes.`

initSessions(self)
  `Initialize all session related attributes.`

initVersions(self)
  `Get and store versions.
  Initialize attributes that store the Webware and WebKit versions as
  both tuples and strings. These are stored in the Properties.py files.`

makeDirs(self)
  `Make sure some standard directories are always available.`

rootURLParser(self)
  `Accessor: the Rool URL parser.
  URL parsing (as defined by subclasses of `URLParser.URLParser`)
  starts here. Other parsers are called in turn by this parser.`

runTransaction(self, trans)
  `Run transation.
  Executes the transaction, handling HTTPException errors.
  Finds the servlet (using the root parser, probably
  `URLParser.ContextParser`, to find the servlet for the
  transaction, then calling `runTransactionViaServlet`.
  Called by `dispatchRawRequest`.`

server(self)
  `Acessor: the AppServer`

serverSidePath(self, path=None)
  `Get the server-side path.
  Returns the absolute server-side path of the WebKit application.
  If the optional path is passed in, then it is joined with the
  server side directory to form a path relative to the app server.`

session(self, sessionId, default=<class 'MiscUtils.NoDefault'>)
  `The session object for `sessionId`.
  Raises `KeyError` if session not found and no default is given.`

sessionCookiePath(self, trans)
  `Get the cookie path for this transaction.
  If not path is specified in the configuration setting,
  the servlet path is used for security reasons, see:
  http://www.net-security.org/dl/articles/cookie_path.pdf`

sessionName(self, trans)
  `Get the name of the field holding the session ID.
  Overwrite to make this transaction dependent.`

sessionPrefix(self, trans)
  `Get the prefix string for the session ID.
  Overwrite to make this transaction dependent.`

sessionTimeout(self, trans)
  `Get the timeout (in seconds) for a user session.
  Overwrite to make this transaction dependent.`

sessions(self)
  `A dictionary of all the session objects.`

shutDown(self)
  `Shut down the application.
  Called by AppServer when it is shuting down. The `__del__` function
  of Application probably won't be called due to circular references.`

startSessionSweeper(self)
  `Start session sweeper.
  Starts the session sweeper, `WebKit.Tasks.SessionTask`, which deletes
  session objects (and disk copies of those objects) that have expired.`

taskManager(self)
  `Accessor: `TaskKit.Scheduler` instance.`

webKitPath(self)
  `The Path of the ``Webware/WebKit/`` directory.`

webKitVersion(self)
  `Return the WebKit version as a tuple.`

webKitVersionString(self)
  `Return the WebKit version as a printable string.`

webwarePath(self)
  `The path of the ``Webware/`` directory.`

webwareVersion(self)
  `Return the Webware version as a tuple.`

webwareVersionString(self)
  `Return the Webware version as a printable string.`

writeActivityLog(self, trans)
  `Write an entry to the activity log.
  Writes an entry to the script log file. Uses settings
  ``ActivityLogFilename`` and ``ActivityLogColumns``.`

writeExceptionReport(self, handler)
  `Write extra information to the exception report.
  See `WebKit.ExceptionHandler` for more information.`

Static methods inherited from WebKit.Application.Application:

addServletFactory(factory)
  `Add a ServletFactory.
  Delegated to the `URLParser.ServletFactoryManager` singleton.`

createRequestForDict(requestDict)
  `Create request object for a given dictionary.
  Create a request object (subclass of `Request`) given the raw
  dictionary as passed by the adapter.
  The class of the request may be based on the contents of the
  dictionary (though only `HTTPRequest` is currently created),
  and the request will later determine the class of the response.
  Called by `dispatchRawRequest`.`

name()
  `The name by which this was started. Usually `AppServer`.`

removePathSession(trans)
  `Remove a possible session identifier from the path.`

resolveInternalRelativePath(trans, url)
  `Return the absolute internal path.
  Given a URL, return the absolute internal URL.
  URLs are assumed relative to the current URL.
  Absolute paths are returned unchanged.`

returnServlet(servlet)
  `Return the servlet to its pool.`

runTransactionViaServlet(servlet, trans)
  `Execute the transaction using the servlet.
  This is the `awake`/`respond`/`sleep` sequence of calls, or if
  the servlet supports it, a single `runTransaction` call (which is
  presumed to make the awake/respond/sleep calls on its own). Using
  `runTransaction` allows the servlet to override the basic call
  sequence, or catch errors from that sequence.
  Called by `runTransaction`.`

Methods inherited from WebKit.ConfigurableForServerSidePath.ConfigurableForServerSidePath:

setting(self, name, default=<class 'MiscUtils.NoDefault'>)
  `Return setting, using the server side path when indicated.
  Returns the setting, filtered by serverSidePath(),
  if the name ends with ``Filename`` or ``Dir``.`

Methods inherited from MiscUtils.Configurable.Configurable:

commandLineConfig(self)
  `Return the settings that came from the command-line.
  These settings come via addCommandLineSetting().`

config(self)
  `Return the configuration of the object as a dictionary.
  This is a combination of defaultConfig() and userConfig().
  This method caches the config.`

configName(self)
  `Return the name of the configuration file without the extension.
  This is the portion of the config file name before the '.config'.
  This is used on the command-line.`

hasSetting(self, name)
  `Check whether a configuration setting has been changed.`

printConfig(self, dest=None)
  `Print the configuration to the given destination.
  The default destination is stdout. A fixed with font is assumed
  for aligning the values to start at the same column.`

setSetting(self, name, value)
  `Set a particular configuration setting.`

userConfig(self)
  `Return the user config overrides.
  These settings can be found in the optional config file.
  Returns {} if there is no such file.
  The config filename is taken from configFilename().`

Data descriptors inherited from MiscUtils.Configurable.Configurable:

__dict__
  `dictionary for instance variables (if defined)`

__weakref__
  `list of weak references to the object (if defined)`

class DummyRequestQueue(__builtin__.object)
`` | `This is a dummy replacement for the request queue. It merely executes handlers as soon as they are "pushed".`

Static methods defined here:

put(handler)

Data descriptors defined here:

__dict__
  `dictionary for instance variables (if defined)`

__weakref__
  `list of weak references to the object (if defined)`

Functions

``

runMainLoopInThread()
  `# Tweak ThreadedAppServer so that it never runs the main loop in a thread:`