"""Context class."""
import History
import Reader
import string
import grailutil
import time
import math
import urllib
import regsub
from Cursors import *
from grailbase.uricontext import URIContext
from urlparse import urljoin,urlparse,urlunparse,urldefrag
VALID_TARGET_STARTS = string.letters + '_'
# TBD: horrible hack. search down for reason. -bwarsaw
LAST_CONTEXT = None
class Context(URIContext):
"""Context for browsing operations.
RATIONALE: After much thinking we uncovered the need for a
separate object to hold the browsing context. This contains items
like the history stack (for the back/forward commands), the loaded
URL (for the reload command), the base URL (for interpreting
relative links), and probably more. These used to be stored in
the browser object, but when introducing frames, each frame will
need its own context. Storing the context in the viewer won't
work either: table cells will be implemented as viewer objects,
but share their browsing context with the containing frame.
Resorting to viewer subclasses, some of which would maintain their
own context and some of which wouldn't, would require overriding
the anchor operations (which need the context) of the context-less
viewers. Having a pointer to a context object in all viewers
makes this much simpler.
"""
def __init__(self, viewer, browser):
URIContext.__init__(self)
self.viewer = viewer
self.browser = browser
self.history = History.History()
self.history_dialog = None
self.app = browser.app
self.root = self.browser.root # XXX Really a Toplevel instance
self.readers = []
self.page = None
self.future = -1
self.source = None
self._target = None
self.last_status_update = 0.0 # Time when last status update was done
self.next_status_update = None # ID of next scheduled status update
self.show_source = 0
self.applet_group = None
self.notifications = [] # callbacks when no readers left
self.image_maps = {} # For ImageMap
self.set_headers({})
self.set_postdata(None)
self.local_api_handlers = {} # This pages local API handlers
def register_notification(self, callback):
if callback not in self.notifications:
self.notifications.append(callback)
def unregister_notification(self, callback):
if callback in self.notifications:
self.notifications.remove(callback)
def notify(self):
for callback in self.notifications:
callback(self)
def clear_reset(self):
self.viewer.clear_reset()
if self.on_top():
self.browser.clear_reset()
self.set_url("")
def on_top(self):
return self.browser.context is self
def set_headers(self, headers):
self.__headers = headers
def get_headers(self):
return self.__headers
def set_postdata(self, data=None):
self.__postdata = data
def get_postdata(self):
return self.__postdata
# Load URL, base URL and target
def set_url(self, url, baseurl=None, target=None, histify=1):
"""Set loaded URL, base URL and target for the current page.
The loaded URL is what this page was loaded from; the base URL
is used to calculate relative links, and defaults to the
loaded URL. The target is the default viewer name
where followed links will appear, and defaults to this viewer.
HISTIFY flag, if true, adds the URL to the history stack.
"""
if url and histify:
# don't lose title if we have one:
title, when = self.app.global_history.lookup_url(url)
self.app.global_history.remember_url(url, title or '')
if not self.page:
self.page = History.PageInfo(url)
self.history.append_page(self.page)
else:
self.page.set_url(url)
self.page.set_title("") # Will be reset from fresh HTML
self.history.refresh()
else:
if self.future >= 0:
self.page = self.history.page(self.future)
self.future = -1
else:
self.page = None
URIContext.set_url(self, url, baseurl=baseurl)
self._target = target
if self.on_top():
self.browser.set_url(self.get_url())
self.applet_group = None
def set_baseurl(self, baseurl=None, target=None):
"""Set the base URL and target for the current page.
The base URL is taken relative to the existing base URL.
"""
URIContext.set_baseurl(self, baseurl)
if target:
self._target = target
def get_target(self):
"""Return the default target for this page (which may be None)."""
return self._target
def follow(self, url, target="", histify=1, scrollpos=None):
"""Follow a link, given by a relative URL.
If the relative URL is a fragment id (#name) on the current
URL, scroll there; otherwise, do a full load of a new page.
"""
newurl, frag = urldefrag(url)
current, f = urldefrag(self.get_url())
if newurl == current:
# XXX This is not correct if we got here through a POST.
context = self.find_window_target(target)
if context is self:
self.follow_local_fragment(url, newurl, frag, histify)
return
self.load(self.get_baseurl(url), target=(target or self._target),
scrollpos=scrollpos)
def follow_local_fragment(self, url, newurl, frag, histify):
if self.readers:
self.readers[-1].fragment = frag
if frag:
self.viewer.scroll_to(frag)
else:
self.viewer.scroll_to_position(self.page.scrollpos())
self.viewer.clear_selection()
self.viewer.remove_temp_tag(histify=1)
baseurl = self.get_baseurl(url)
page = self.page
self.page = None # triggers set_url() to update history
self.set_url(baseurl, histify=histify)
if self.future >= 0:
self.page = self.history.page(self.future)
self.future = -1
self.page.set_title(page.title())
self.history.refresh()
self.browser.set_title(page.title())
# Misc
def get_formdata(self):
return self.page and self.page.formdata()
# Message interfaces
def message(self, string=""):
self.viewer.message(string)
enter = message # XXX ImageMap backward compatibility
def message_clear(self):
self.new_reader_status()
leave = message_clear # XXX ImageMap backward compatibility
def new_reader_status(self):
if self.app.iostatuspanel:
self.app.iostatuspanel.update()
now = time.time()
seconds = math.floor(now)
if self.last_status_update == seconds:
if self.next_status_update:
return
self.next_status_update = self.browser.root.after(
1000 - int(1000*(now%1.0)),
self.new_reader_status)
return
self.last_status_update = seconds
self.next_status_update = None
if self.readers:
nr = len(self.readers)
nw = 0
if nr == 1:
message = str(self.readers[0])
else:
nbytes = 0
maxbytes = 0
cached = 0
for reader in self.readers:
nbytes = nbytes + reader.nbytes
if reader.message == "waiting for socket":
nw = nw + 1
if reader.maxbytes > 0 and maxbytes >= 0:
maxbytes = maxbytes + reader.maxbytes
else:
maxbytes = -1
if reader.api.iscached():
cached = cached + 1
if maxbytes > 0:
percent = nbytes*100/maxbytes
message = "%d%% of %s read" % (
percent, grailutil.nicebytes(maxbytes))
else:
message = "%s read" % grailutil.nicebytes(nbytes)
if cached == nr:
message = message + " (all cached)"
elif cached:
message = message + " (%d cached)" % cached
message = "%d streams, %d active: %s" % (nr, nr - nw, message)
elif self.on_top():
message = ""
elif self.get_url():
message = "URL: %s" % self.get_url()
else:
message = "empty"
self.message(message)
def error_dialog(self, exception, msg):
if self.app:
self.app.error_dialog(exception, msg, root=self.root)
else:
print "ERROR:", msg
def set_title(self, title):
if not title:
title, when = self.app.global_history.lookup_url(self.get_url())
title = title or ''
self.app.global_history.remember_url(self.get_url(), title)
if self.on_top():
self.browser.set_title(title)
if self.page:
self.page.set_title(title)
self.history.refresh()
# Handle (a)synchronous images
def get_image(self, src):
image = self.get_async_image(src)
if image:
if not image.load_synchronously(self):
image = None
return image
def get_async_image(self, src, reload=0, width=0, height=0):
# check out the request
if not src: return None
url = self.get_baseurl(src)
if not url: return None
if not self.app.load_images: return None
# try loading from the cache
image = self.app.get_cached_image((url, width, height))
if image and (not reload or image.is_reloading()):
if not image.loaded:
image.start_loading(self)
return image
# it's not in the cache.
from AsyncImage import AsyncImage
try:
image = AsyncImage(self, url, reload, width=width, height=height,
master=self.root)
except IOError, msg:
image = None
if image:
self.app.set_cached_image(
image.get_cache_key(), image, self.viewer)
if self.app.load_images:
image.start_loading(self)
return image
# Navigation/history commands
def go_back(self, event=None):
if not self.load_from_history(self.history.peek(-1)):
if self.viewer.parent:
# Remove any local API handlers
self.viewer.parent.context.remove_local_api_handlers()
# go out one level:
self.viewer.parent.context.go_back(event)
else:
self.root.bell()
def go_forward(self, event=None):
self.load_from_history(self.history.peek(+1))
def reload_page(self):
self.load_from_history(self.history.peek(0), reload=1)
def load_from_history(self, (future, page), reload=0):
if not page:
return 0
self.future = future
if not reload:
self.follow(page.url(), histify=0, scrollpos=page.scrollpos(),
target="_self")
else:
self.load(page.url(), reload=reload, scrollpos=page.scrollpos(),
target="_self")
return 1
def show_history_dialog(self):
if not self.history_dialog:
self.history_dialog = History.HistoryDialog(self, self.history)
self.history.set_dialog(self.history_dialog)
else:
self.history_dialog.show()
def clone_history_from(self, other):
self.history = other.history.clone()
self.future, page = self.history.peek()
if page:
self.load(page.url(), scrollpos=page.scrollpos())
# Internals handle loading pages
def save_page_state(self, reload=0):
if not self.page: return
# Save page scroll position
self.page.set_scrollpos(self.viewer.scrollpos())
# Save form contents even if reloading
formdata = []
if hasattr(self, 'forms'):
for fi in self.forms:
formdata.append(fi.get())
# remove the attribute
del self.forms
self.page.set_formdata(formdata)
def read_page(self, url, method, params, show_source=0, reload=0,
scrollpos=None, data=None):
# TBD: this is a horrid hack used so that
# mailtoAPI.mailto_access can get at the URL of the page that
# the user has clicked off of. -baw
self.set_postdata(data)
global LAST_CONTEXT
LAST_CONTEXT = self
from Reader import Reader
Reader(self, url, method, params, show_source, reload, data, scrollpos)
# Applet Protocol Handler interface
def set_local_api(self, name, klass):
"""Install a local protocol handler"""
if name[-3:] <> "API":
raise IOError, "Invalid name (%s) for protocol handler"
self.local_api_handlers[name] = klass
def get_local_api(self, url, method, params):
"""get a local handler instance"""
scheme, resturl = urllib.splittype(url)
if not scheme:
raise IOError, ("protocol error",
"no scheme identifier in URL", url)
scheme = string.lower(scheme)
sanitized = regsub.gsub("[^a-zA-Z0-9]", "_", scheme)
modname = sanitized + "API"
try:
klass = self.local_api_handlers[modname]
except KeyError:
return None
handler = klass(resturl, method, params)
handler._url_ = url # To keep BaseReader happy
return handler
def remove_local_api_handlers(self):
"""Remove any local handlers from the current context"""
if self.local_api_handlers:
self.local_api_handlers = {}
# External user commands
def save_document(self, *relurls):
"""Save document to a file.
Returns true if the x-fer was initiated; allows histification.
"""
# File/Save As...
url = apply(self.get_baseurl, relurls)
if url == self.get_url() and self.busycheck(): return 0
import FileDialog, os
fd = FileDialog.SaveFileDialog(self.root)
# give it a default filename on which save within the
# current directory
import urllib
if urllib.splittype(url)[0] == "data":
default = ""
else:
urlasfile = string.splitfields(url, '/')
default = urlasfile[-1]
# strip trailing query
i = string.find(default, '?')
if i > 0: default = default[:i]
# strip trailing fragment
i = string.rfind(default, '#')
if i > 0: default = default[:i]
# maybe bogus assumption?
if not default: default = 'index.html'
file = fd.go(default=default, key="save")
if not file: return 0
#
SavingReader(self, url, 'GET', {}, 0, 0, filename=file)
self.message_clear()
return 1
def print_document(self):
# File/Print...
if self.busycheck(): return
import PrintDialog
PrintDialog.PrintDialog(self,
self.get_url(),
self.get_title())
def view_source(self):
from Browser import Browser
browser = Browser(self.app.root, self.app, height=24)
browser.context.load(self.get_url(), show_source=1)
# Externals for loading pages
def load(self, url, method='GET', params={},
show_source=0, reload=0, scrollpos=None,
target="", source=None):
# Update state of current page, in case we re-visit it via the
# history mechanism.
if not source:
source = self.viewer
if self.source and self.source is not source:
self.source.remove_temp_tag()
self.source = source
context = self.find_window_target(target)
if context is not self:
context.load(url, method, params, show_source,
reload, scrollpos, "_self", source)
return
self.stop()
self.save_page_state()
# Start loading a new URL into the window
self.message("Loading %s" % url)
if reload:
show_source = self.show_source
else:
self.show_source = show_source
try:
self.read_page(url, method, params,
show_source=show_source, reload=reload,
scrollpos=scrollpos)
self.show_source = show_source
except IOError, msg:
self.error_dialog(IOError, msg)
self.message_clear()
if self.source:
self.source.remove_temp_tag()
self.source = None
def find_window_target(self, target):
"""Return a context gotten from the target; by default self."""
context = None
if target and target[0] not in VALID_TARGET_STARTS:
target = ""
if target == self.viewer.name:
target = ""
if target:
if target[0] == "_":
if target == "_blank":
newbrowser = self.browser.new_command()
context = newbrowser.context
elif target == "_self":
pass
elif target == "_parent":
parentviewer = self.viewer.find_parentviewer()
context = parentviewer and parentviewer.context
elif target == "_top":
context = self.browser.context
target = ""
else:
# First try to find the target in the current browser
viewer = self.browser.context.viewer.find_subviewer(target)
if not viewer:
# Try to find another browser with this name
for browser in self.app.browsers:
if browser.viewer.name == target:
viewer = browser.viewer
break
if not viewer:
# Try to find a frame inside other browsers
for browser in self.app.browsers:
if browser is self.browser: continue
viewer = browser.context.viewer.find_subviewer(target)
if viewer:
break
if not viewer:
# Create a new browser with this name
newbrowser = self.browser.new_command()
viewer = newbrowser.context.viewer
viewer.name = target # XXX Naughty ;-)
context = viewer.context
if context and context is not self:
context.source = self.source
self.source = None
return context or self
def post(self, url, data="", params={}, target=""):
# Post form data
context = self.find_window_target(target)
if context is not self:
context.post(url, data, params, target)
return
self.stop()
self.save_page_state()
url = self.get_baseurl(url)
method = 'POST'
self.message("Posting to %s" % url)
try:
self.read_page(url, method, params, reload=1, data=data)
except IOError, msg:
self.error_dialog(IOError, msg)
self.message_clear()
# Externals for managing list of active readers
def addreader(self, reader):
self.readers.append(reader)
if self.on_top():
self.browser.allowstop()
self.new_reader_status()
def rmreader(self, reader):
if reader in self.readers:
self.readers.remove(reader)
if not self.readers:
if self.on_top():
self.browser.clearstop()
if self.source:
self.source.remove_temp_tag(histify=1)
self.source = None
self.notify()
self.new_reader_status()
def busy(self):
return not not self.readers
def busycheck(self):
if self.readers:
self.error_dialog('Busy',
"Please wait until the transfer is done (or stop it)")
return 1
return 0
def stop(self):
for reader in self.readers[:]:
reader.kill()
# Page interface
def get_title(self):
url = self.get_url()
title, when = self.app.global_history.lookup_url(url)
if not title:
title = self.page and self.page.title() or url
return title
class SimpleContext(Context):
# this can be used when interactive updates are not desired
def new_reader_status(self): pass
def on_top(self): return 0
class SavingReader(Reader.Reader):
def __init__(self, context, url, *args, **kw):
self.__filename = kw['filename']
del kw['filename']
apply(Reader.Reader.__init__, (self, context, '') + args, kw)
context.rmreader(self)
self.url = url
self.restart(url)
def handle_meta(self, errcode, errmsg, headers):
if not self.handle_meta_prelim(errcode, errmsg, headers):
return
# now save:
self.stop()
try:
self.save_file = open(self.__filename, "wb")
except IOError, msg:
self.context.error_dialog(IOError, msg)
return
#
# add to history without destroying any title already known:
#
history = grailutil.get_grailapp().global_history
title, when = history.lookup_url(self.url)
history.remember_url(self.url, title or '')
#
Reader.TransferDisplay(self.last_context, self.__filename, self)
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