From: Brian Warner Date: Wed, 28 Mar 2007 18:24:53 +0000 (-0700) Subject: document IEncoder, add Encoder.set_landlords() X-Git-Url: https://git.rkrishnan.org/%5B/%5D%20/file/URI:LIT:krugkidfnzsc4/COPYING.TGPPL.html?a=commitdiff_plain;h=c4f09833f5a853f3bee01247b2d401742881fdde;p=tahoe-lafs%2Ftahoe-lafs.git document IEncoder, add Encoder.set_landlords() --- diff --git a/src/allmydata/encode_new.py b/src/allmydata/encode_new.py index bf734f1a..88ca52af 100644 --- a/src/allmydata/encode_new.py +++ b/src/allmydata/encode_new.py @@ -1,11 +1,13 @@ # -*- test-case-name: allmydata.test.test_encode -*- +from zope.interface import implements from twisted.internet import defer from allmydata.chunk import HashTree, roundup_pow2 from allmydata.Crypto.Cipher import AES import sha from allmydata.util import mathutil from allmydata.codec import CRSEncoder +from allmydata.interfaces import IEncoder def hash(data): return sha.new(data).digest() @@ -76,6 +78,7 @@ TiB=1024*GiB PiB=1024*TiB class Encoder(object): + implements(IEncoder) def setup(self, infile): self.infile = infile @@ -169,6 +172,9 @@ class Encoder(object): # return self.send(shareid, "write", subshare, offset) return self.send(shareid, "put_subshare", segment_num, subshare) + def set_landlords(self, landlords): + self.landlords = landlords.copy() + def send(self, shareid, methname, *args, **kwargs): ll = self.landlords[shareid] return ll.callRemote(methname, *args, **kwargs) diff --git a/src/allmydata/interfaces.py b/src/allmydata/interfaces.py index 63bb6c53..38ac1308 100644 --- a/src/allmydata/interfaces.py +++ b/src/allmydata/interfaces.py @@ -283,6 +283,49 @@ class ICodecDecoder(Interface): call. """ +class IEncoder(Interface): + """I take a sequence of plaintext bytes and a list of shareholders, then + encrypt, encode, hash, and deliver shares to those shareholders. I will + compute all the necessary Merkle hash trees that are necessary to + validate the data that eventually comes back from the shareholders. I + provide the root hash of the hash tree, and the encoding parameters, both + of which must be included in the URI. + + I do not choose shareholders, that is left to the IUploader. I must be + given a dict of RemoteReferences to storage buckets that are ready and + willing to receive data. + """ + + def setup(infile): + """I take a file-like object (providing seek, tell, and read) from + which all the plaintext data that is to be uploaded can be read. I + will seek to the beginning of the file before reading any data. + setup() must be called before making any other calls, in particular + before calling get_reservation_size(). + """ + + def get_reservation_size(): + """I return the size of the data that will be stored on each + shareholder. It is useful to determine this size before asking + potential shareholders whether they will grant a lease or not, since + their answers will depend upon how much space we need. + """ + + def set_shareholders(shareholders): + """I take a dictionary that maps share identifiers (small integers, + starting at 0) to RemoteReferences that provide RIBucketWriter. This + mus be called before start(). + """ + + def start(): + """I start the upload. This process involves reading data from the + input file, encrypting it, encoding the pieces, uploading the shares + to the shareholders, then sending the hash trees. + + I return a Deferred that fires with the root hash. + """ + + class IDownloadTarget(Interface): def open(): """Called before any calls to write() or close()."""