tahoe-lafs/src/allmydata/web/filenode.py
2008-05-20 12:36:02 -07:00

389 lines
15 KiB
Python

import simplejson
from zope.interface import implements
from twisted.internet.interfaces import IConsumer
from twisted.web import http, static, resource, server
from twisted.internet import defer
from nevow import url, rend
from nevow.inevow import IRequest
from allmydata.upload import FileHandle
from allmydata.interfaces import IDownloadTarget, ExistingChildError
from allmydata.mutable.common import MODE_READ
from allmydata.util import log
from allmydata.web.common import text_plain, WebError, IClient, RenderMixin, \
boolean_of_arg, get_arg, should_create_intermediate_directories
class ReplaceMeMixin:
def replace_me_with_a_child(self, ctx, replace):
# a new file is being uploaded in our place.
req = IRequest(ctx)
client = IClient(ctx)
mutable = boolean_of_arg(get_arg(req, "mutable", "false"))
if mutable:
req.content.seek(0)
data = req.content.read()
d = client.create_mutable_file(data)
def _uploaded(newnode):
d2 = self.parentnode.set_node(self.name, newnode,
overwrite=replace)
d2.addCallback(lambda res: newnode)
return d2
d.addCallback(_uploaded)
else:
uploadable = FileHandle(req.content, convergence=client.convergence)
d = self.parentnode.add_file(self.name, uploadable,
overwrite=replace)
def _done(filenode):
log.msg("webish upload complete",
facility="tahoe.webish", level=log.NOISY)
if self.node:
# we've replaced an existing file (or modified a mutable
# file), so the response code is 200
req.setResponseCode(http.OK)
else:
# we've created a new file, so the code is 201
req.setResponseCode(http.CREATED)
return filenode.get_uri()
d.addCallback(_done)
return d
def replace_me_with_a_childcap(self, ctx, replace):
req = IRequest(ctx)
req.content.seek(0)
childcap = req.content.read()
client = IClient(ctx)
childnode = client.create_node_from_uri(childcap)
d = self.parentnode.set_node(self.name, childnode, overwrite=replace)
d.addCallback(lambda res: childnode.get_uri())
return d
def _read_data_from_formpost(self, req):
# SDMF: files are small, and we can only upload data, so we read
# the whole file into memory before uploading.
contents = req.fields["file"]
contents.file.seek(0)
data = contents.file.read()
return data
def replace_me_with_a_formpost(self, ctx, replace):
# create a new file, maybe mutable, maybe immutable
req = IRequest(ctx)
client = IClient(ctx)
mutable = boolean_of_arg(get_arg(req, "mutable", "false"))
if mutable:
data = self._read_data_from_formpost(req)
d = client.create_mutable_file(data)
def _uploaded(newnode):
d2 = self.parentnode.set_node(self.name, newnode,
overwrite=replace)
d2.addCallback(lambda res: newnode.get_uri())
return d2
d.addCallback(_uploaded)
return d
# create an immutable file
contents = req.fields["file"]
uploadable = FileHandle(contents.file, convergence=client.convergence)
d = self.parentnode.add_file(self.name, uploadable, overwrite=replace)
d.addCallback(lambda newnode: newnode.get_uri())
return d
class PlaceHolderNodeHandler(RenderMixin, rend.Page, ReplaceMeMixin):
def __init__(self, parentnode, name):
rend.Page.__init__(self)
assert parentnode
self.parentnode = parentnode
self.name = name
self.node = None
def render_PUT(self, ctx):
req = IRequest(ctx)
t = get_arg(req, "t", "").strip()
replace = boolean_of_arg(get_arg(req, "replace", "true"))
assert self.parentnode and self.name
if not t:
return self.replace_me_with_a_child(ctx, replace)
if t == "uri":
return self.replace_me_with_a_childcap(ctx, replace)
raise WebError("PUT to a file: bad t=%s" % t)
def render_POST(self, ctx):
req = IRequest(ctx)
t = get_arg(req, "t", "").strip()
replace = boolean_of_arg(get_arg(req, "replace", "true"))
if t == "upload":
# like PUT, but get the file data from an HTML form's input field.
# We could get here from POST /uri/mutablefilecap?t=upload,
# or POST /uri/path/file?t=upload, or
# POST /uri/path/dir?t=upload&name=foo . All have the same
# behavior, we just ignore any name= argument
d = self.replace_me_with_a_formpost(ctx, replace)
else:
# t=mkdir is handled in DirectoryNodeHandler._POST_mkdir, so
# there are no other t= values left to be handled by the
# placeholder.
raise WebError("POST to a file: bad t=%s" % t)
when_done = get_arg(req, "when_done", None)
if when_done:
d.addCallback(lambda res: url.URL.fromString(when_done))
return d
class FileNodeHandler(RenderMixin, rend.Page, ReplaceMeMixin):
def __init__(self, node, parentnode=None, name=None):
rend.Page.__init__(self)
assert node
self.node = node
self.parentnode = parentnode
self.name = name
def childFactory(self, ctx, name):
req = IRequest(ctx)
if should_create_intermediate_directories(req):
raise WebError("Cannot create directory '%s', because its "
"parent is a file, not a directory" % name)
raise WebError("Files have no children, certainly not named '%s'"
% name)
def render_GET(self, ctx):
req = IRequest(ctx)
t = get_arg(req, "t", "").strip()
if not t:
# just get the contents
filename = get_arg(req, "filename", self.name) or "unknown"
save_to_file = boolean_of_arg(get_arg(req, "save", "False"))
return FileDownloader(self.node, filename, save_to_file)
if t == "json":
return FileJSONMetadata(ctx, self.node)
if t == "uri":
return FileURI(ctx, self.node)
if t == "readonly-uri":
return FileReadOnlyURI(ctx, self.node)
raise WebError("GET file: bad t=%s" % t)
def render_HEAD(self, ctx):
req = IRequest(ctx)
t = get_arg(req, "t", "").strip()
if t:
raise WebError("GET file: bad t=%s" % t)
if self.node.is_mutable():
# update the servermap to get the size of this file without
# downloading the full contents.
d = self.node.get_servermap(MODE_READ)
def _got_servermap(smap):
ver = smap.best_recoverable_version()
if not ver:
raise WebError("Unable to recover this file",
http.NOT_FOUND)
length = smap.size_of_version(ver)
return length
d.addCallback(_got_servermap)
# otherwise, we can get the size from the URI
else:
d = defer.succeed(self.node.get_size())
def _got_length(length):
req.setHeader("content-length", length)
return ""
d.addCallback(_got_length)
return d
def render_PUT(self, ctx):
req = IRequest(ctx)
t = get_arg(req, "t", "").strip()
replace = boolean_of_arg(get_arg(req, "replace", "true"))
if not t:
if self.node.is_mutable():
return self.replace_my_contents(ctx)
if not replace:
# this is the early trap: if someone else modifies the
# directory while we're uploading, the add_file(overwrite=)
# call in replace_me_with_a_child will do the late trap.
raise ExistingChildError()
assert self.parentnode and self.name
return self.replace_me_with_a_child(ctx, replace)
if t == "uri":
if not replace:
raise ExistingChildError()
assert self.parentnode and self.name
return self.replace_me_with_a_childcap(ctx, replace)
raise WebError("PUT to a file: bad t=%s" % t)
def render_POST(self, ctx):
req = IRequest(ctx)
t = get_arg(req, "t", "").strip()
replace = boolean_of_arg(get_arg(req, "replace", "true"))
if t == "check":
d = self._POST_check(req)
elif t == "upload":
# like PUT, but get the file data from an HTML form's input field
# We could get here from POST /uri/mutablefilecap?t=upload,
# or POST /uri/path/file?t=upload, or
# POST /uri/path/dir?t=upload&name=foo . All have the same
# behavior, we just ignore any name= argument
if self.node.is_mutable():
d = self.replace_my_contents_with_a_formpost(ctx)
else:
if not replace:
raise ExistingChildError()
assert self.parentnode and self.name
d = self.replace_me_with_a_formpost(ctx, replace)
else:
raise WebError("POST to file: bad t=%s" % t)
when_done = get_arg(req, "when_done", None)
if when_done:
d.addCallback(lambda res: url.URL.fromString(when_done))
return d
def _POST_check(self, req):
d = self.node.check()
def _done(res):
log.msg("checked %s, results %s" % (self.node, res),
facility="tahoe.webish", level=log.NOISY)
return str(res)
d.addCallback(_done)
# TODO: results
return d
def render_DELETE(self, ctx):
assert self.parentnode and self.name
d = self.parentnode.delete(self.name)
d.addCallback(lambda res: self.node.get_uri())
return d
def replace_my_contents(self, ctx):
req = IRequest(ctx)
req.content.seek(0)
new_contents = req.content.read()
d = self.node.overwrite(new_contents)
d.addCallback(lambda res: self.node.get_uri())
return d
def replace_my_contents_with_a_formpost(self, ctx):
# we have a mutable file. Get the data from the formpost, and replace
# the mutable file's contents with it.
req = IRequest(ctx)
new_contents = self._read_data_from_formpost(req)
d = self.node.overwrite(new_contents)
d.addCallback(lambda res: self.node.get_uri())
return d
class WebDownloadTarget:
implements(IDownloadTarget, IConsumer)
def __init__(self, req, content_type, content_encoding, save_to_filename):
self._req = req
self._content_type = content_type
self._content_encoding = content_encoding
self._opened = False
self._producer = None
self._save_to_filename = save_to_filename
def registerProducer(self, producer, streaming):
self._req.registerProducer(producer, streaming)
def unregisterProducer(self):
self._req.unregisterProducer()
def open(self, size):
self._opened = True
self._req.setHeader("content-type", self._content_type)
if self._content_encoding:
self._req.setHeader("content-encoding", self._content_encoding)
self._req.setHeader("content-length", str(size))
if self._save_to_filename is not None:
# tell the browser to save the file rather display it
# TODO: indicate charset of filename= properly
filename = self._save_to_filename.encode("utf-8")
self._req.setHeader("content-disposition",
'attachment; filename="%s"'
% filename)
def write(self, data):
self._req.write(data)
def close(self):
self._req.finish()
def fail(self, why):
if self._opened:
# The content-type is already set, and the response code
# has already been sent, so we can't provide a clean error
# indication. We can emit text (which a browser might interpret
# as something else), and if we sent a Size header, they might
# notice that we've truncated the data. Keep the error message
# small to improve the chances of having our error response be
# shorter than the intended results.
#
# We don't have a lot of options, unfortunately.
self._req.write("problem during download\n")
else:
# We haven't written anything yet, so we can provide a sensible
# error message.
msg = str(why.type)
msg.replace("\n", "|")
self._req.setResponseCode(http.GONE, msg)
self._req.setHeader("content-type", "text/plain")
# TODO: HTML-formatted exception?
self._req.write(str(why))
self._req.finish()
def register_canceller(self, cb):
pass
def finish(self):
pass
class FileDownloader(resource.Resource):
# since we override the rendering process (to let the tahoe Downloader
# drive things), we must inherit from regular old twisted.web.resource
# instead of nevow.rend.Page . Nevow will use adapters to wrap a
# nevow.appserver.OldResourceAdapter around any
# twisted.web.resource.IResource that it is given. TODO: it looks like
# that wrapper would allow us to return a Deferred from render(), which
# might could simplify the implementation of WebDownloadTarget.
def __init__(self, filenode, filename, save_to_file):
resource.Resource.__init__(self)
self.filenode = filenode
self.filename = filename
self.save_to_file = save_to_file
def render(self, req):
gte = static.getTypeAndEncoding
ctype, encoding = gte(self.filename,
static.File.contentTypes,
static.File.contentEncodings,
defaultType="text/plain")
save_to_filename = None
if self.save_to_file:
save_to_filename = self.filename
wdt = WebDownloadTarget(req, ctype, encoding, save_to_filename)
d = self.filenode.download(wdt)
# exceptions during download are handled by the WebDownloadTarget
d.addErrback(lambda why: None)
return server.NOT_DONE_YET
def FileJSONMetadata(ctx, filenode):
file_uri = filenode.get_uri()
data = ("filenode",
{'ro_uri': file_uri,
'size': filenode.get_size(),
})
return text_plain(simplejson.dumps(data, indent=1), ctx)
def FileURI(ctx, filenode):
return text_plain(filenode.get_uri(), ctx)
def FileReadOnlyURI(ctx, filenode):
if filenode.is_readonly():
return text_plain(filenode.get_uri(), ctx)
return text_plain(filenode.get_readonly_uri(), ctx)
class FileNodeDownloadHandler(FileNodeHandler):
def childFactory(self, ctx, name):
return FileNodeDownloadHandler(self.node, name=name)