This is a change I've wanted to make for many years, because when we get
to HTTP-based servers, we won't have tubids for them. What held me back
was that there's code all over the place that uses the serverid for
various purposes, so I wasn't sure it was safe. I did a big push a few
years ago to use IServer instances instead of serverids in most
places (in #1363), and to split out the values that actually depend upon
tubid into separate accessors (like get_lease_seed and
get_foolscap_write_enabler_seed), which I think took care of all the
important uses.
There are a number of places that use get_serverid() as dictionary key
to track shares (Checker results, mutable servermap). I believe these
are happy to use pubkeys instead of tubids: the only thing they do with
get_serverid() is to compare it to other values obtained from
get_serverid(). A few places in the WUI used serverid to compute display
values: these were fixed.
The main trouble was the Helper: it returns a HelperUploadResults (a
Copyable) with a share->server mapping that's keyed by whatever the
Helper's get_serverid() returns. If the uploader and the helper are on
different sides of this change, the Helper could return values that the
uploader won't recognize. This is cosmetic: that mapping is only used to
display the upload results on the "Recent and Active Operations" page.
I've added code to StorageFarmBroker.get_stub_server() to fall back to
tubids when looking up a server, so this should still work correctly
when the uploader is new and the Helper is old. If the Helper is new and
the uploader is old, the upload results will show unusual server ids.
refs ticket:1363
This stores IDisplayableServer-providing instances (StubServers or
NativeStorageServers) in the .servermap and .sharemap dictionaries. But
get_servermap()/get_sharemap() still return data structures with
serverids, not IServers, by translating their data on the way out. This
lets us put off changing the callers for a little bit longer.
Complete the getter-based transformation, by hiding ".uri" and updating
callers to use get_uri(). Also don't set a dummy self._uri, leave it
undefined until someone calls set_uri().
This hides attributes with e.g. _sharemap, and creates getters like
get_sharemap() to access them, for every field except .uri . This will
make it easier to modify the internal representation of .sharemap
without requiring callers to adjust quite yet.
".uri" has so many users that it seemed better to update it in a
subsequent patch.
Populate most of UploadResults (except .uri, which is learned later when
using a Helper) in the constructor, instead of allowing creators to
write to attributes later. This will help isolate the fields that we
want to change to use IServers.
This splits the pb.Copyable on-wire object (HelperUploadResults) out
from the local results object (UploadResults). To maintain compatibility
with older Helpers, we have to leave pb.Copyable classes alone and
unmodified, but we want to change UploadResults to use IServers instead
of serverids. So by using a different class on the wire, and translating
to/from it on either end, we can accomplish both.
This consistently records all immutable uploads in the Recent Uploads And
Downloads page, regardless of code path. Previously, certain webapi upload
operations (like PUT /uri/$DIRCAP/newchildname) failed to pass the History
object and were left out.
This patch was originally written by Brian, but was re-recorded by Zooko to use
darcs replace instead of hunks for any file in which it would result in fewer
total hunks.
refs #1363
This patch was written by Brian but was re-recorded by Zooko (with David-Sarah looking on) to use darcs replace instead of editing to rename the three variables to their new names.
refs #1363
No behavioral changes, just updating variable/method names and log messages.
The effects outside these three files should be minimal: some exception
messages changed (to say "server" instead of "peer"), and some internal class
names were changed. A few things still use "peer" to minimize external
changes, like UploadResults.timings["peer_selection"] and
happinessutil.merge_peers, which can be changed later.
Pass around IServer instance instead of (peerid, rref) tuple. Replace
"descriptor" with "server". Other replacements:
get_all_servers -> get_connected_servers/get_known_servers
get_servers_for_index -> get_servers_for_psi (now returns IServers)
This change still needs to be pushed further down: lots of code is now
getting the IServer and then distributing (peerid, rref) internally.
Instead, it ought to distribute the IServer internally and delay
extracting a serverid or rref until the last moment.
no_network.py was updated to retain parallelism.
- Make some important utility functions clearer and more thoroughly
documented.
- Assert in upload.servers_of_happiness that the buckets attributes
of PeerTrackers passed to it are mutually disjoint.
- Get rid of some silly non-Pythonisms that I didn't see when I first
wrote these patches.
- Make sure that should_add_server returns true when queried about a
shnum that it doesn't know about yet.
- Change Tahoe2PeerSelector.preexisting_shares to map a shareid to a set
of peerids, alter dependencies to deal with that.
- Remove upload.should_add_servers, because it is no longer necessary
- Move upload.shares_of_happiness and upload.shares_by_server to a utility
file.
- Change some points in Tahoe2PeerSelector.
- Compute servers_of_happiness using a bipartite matching algorithm that
we know is optimal instead of an ad-hoc greedy algorithm that isn't.
- Change servers_of_happiness to just take a sharemap as an argument,
change its callers to merge existing_shares and used_peers before
calling it.
- Change an error message in the encoder to be more appropriate for
servers of happiness.
- Clarify the wording of an error message in immutable/upload.py
- Refactor a happiness failure message to happinessutil.py, and make
immutable/upload.py and immutable/encode.py use it.
- Move the word "only" as far to the right as possible in failure
messages.
- Use a better definition of progress during peer selection.
- Do read-only peer share detection queries in parallel, not sequentially.
- Clean up logging semantics; print the query statistics whenever an
upload is unsuccessful, not just in one case.
When I first implemented #778, I just altered the error messages to refer to
servers where they referred to shares. The resulting error messages weren't
very good. These are a bit better.
The Tahoe2PeerSelector returned either NoSharesError or NotEnoughSharesError
for a variety of error conditions that weren't informatively described by them.
This patch creates a new error, UploadHappinessError, replaces uses of
NoSharesError and NotEnoughSharesError with it, and alters the error message
raised with the errors to be more in line with the new servers_of_happiness
behavior. See ticket #834 for more information.
* stop using IURI as an adapter
* pass cap strings around instead of URI instances
* move filenode/dirnode creation duties from Client to new NodeMaker class
* move other Client duties to KeyGenerator, SecretHolder, History classes
* stop passing Client reference to dirnode/filenode constructors
- pass less-powerful references instead, like StorageBroker or Uploader
* always create DirectoryNodes by wrapping a filenode (mutable for now)
* remove some specialized mock classes from unit tests
Detailed list of changes (done one at a time, then merged together)
always pass a string to create_node_from_uri(), not an IURI instance
always pass a string to IFilesystemNode constructors, not an IURI instance
stop using IURI() as an adapter, switch on cap prefix in create_node_from_uri()
client.py: move SecretHolder code out to a separate class
test_web.py: hush pyflakes
client.py: move NodeMaker functionality out into a separate object
LiteralFileNode: stop storing a Client reference
immutable Checker: remove Client reference, it only needs a SecretHolder
immutable Upload: remove Client reference, leave SecretHolder and StorageBroker
immutable Repairer: replace Client reference with StorageBroker and SecretHolder
immutable FileNode: remove Client reference
mutable.Publish: stop passing Client
mutable.ServermapUpdater: get StorageBroker in constructor, not by peeking into Client reference
MutableChecker: reference StorageBroker and History directly, not through Client
mutable.FileNode: removed unused indirection to checker classes
mutable.FileNode: remove Client reference
client.py: move RSA key generation into a separate class, so it can be passed to the nodemaker
move create_mutable_file() into NodeMaker
test_dirnode.py: stop using FakeClient mockups, use NoNetworkGrid instead. This simplifies the code, but takes longer to run (17s instead of 6s). This should come down later when other cleanups make it possible to use simpler (non-RSA) fake mutable files for dirnode tests.
test_mutable.py: clean up basedir names
client.py: move create_empty_dirnode() into NodeMaker
dirnode.py: get rid of DirectoryNode.create
remove DirectoryNode.init_from_uri, refactor NodeMaker for customization, simplify test_web's mock Client to match
stop passing Client to DirectoryNode, make DirectoryNode.create_with_mutablefile the normal DirectoryNode constructor, start removing client from NodeMaker
remove Client from NodeMaker
move helper status into History, pass History to web.Status instead of Client
test_mutable.py: fix minor typo
and deny the Helper the ability to mount a partial-information-guessing
attack. This will probably break compatibility between new clients and very
old (pre-1.0) helpers.
This implements an immutable repairer by marrying a CiphertextDownloader to a CHKUploader. It extends the IDownloadTarget interface so that the downloader can provide some metadata that the uploader requires.
The processing is incremental -- it uploads the first segments before it finishes downloading the whole file. This is necessary so that you can repair large files without running out of RAM or using a temporary file on the repairer.
It requires only a verifycap, not a readcap. That is: it doesn't need or use the decryption key, only the integrity check codes.
There are several tests marked TODO and several instances of XXX in the source code. I intend to open tickets to document further improvements to functionality and testing, but the current version is probably good enough for Tahoe-1.3.0.
It used to be a map from shnum to a string saying "placed this share on XYZ server". The new definition is more in keeping with the "sharemap" object that results from immutable file checking and repair, and it is more useful to the repairer, which is a consumer of immutable upload results.
This makes Uploader take an EncryptedUploadable object instead of an Uploadable object. I also changed it to return a verify cap instead of a tuple of the bits of data that one finds in a verify cap.
This will facilitate hooking together an Uploader and a Downloader to make a Repairer.
Also move offloaded.py into src/allmydata/immutable/.