Because Brian argues that the file contains a description of the wui as well as of the wapi, and because the name "webapi.txt" might be more obvious to the untrained eye.
This is necessary, because if setuptools looks at the directory listing, then it follows the link named "More Info" in attempt to download the file, and this fails.
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.
Rename "downloadable" to "target".
Rename "u" to "v" in FileDownloader.__init__().
Rename "_uri" to "_verifycap" in FileDownloader.
Rename "_downloadable" to "_target" in FileDownloader.
Rename "FileDownloader" to "CiphertextDownloader".
FileDownloader takes a verify cap and produces ciphertext, instead of taking a read cap and producing plaintext.
FileDownloader does all integrity checking including the mandatory ciphertext hash tree and the optional ciphertext flat hash, rather than expecting its target to do some of that checking.
Rename immutable.download.Output to immutable.download.DecryptingOutput. An instance of DecryptingOutput can be passed to FileDownloader to use as the latter's target. Text pushed to the DecryptingOutput is decrypted and then pushed to *its* target.
DecryptingOutput satisfies the IConsumer interface, and if its target also satisfies IConsumer, then it forwards and pause/unpause signals to its producer (which is the FileDownloader).
This patch also changes some logging code to use the new logging mixin class.
Check integrity of a segment and decrypt the segment one block-sized buffer at a time instead of copying the buffers together into one segment-sized buffer (reduces peak memory usage, I think, and is probably a tad faster/less CPU, depending on your encoding parameters).
Refactor FileDownloader so that processing of segments and of tail-segment share as much code is possible.
FileDownloader and FileNode take caps as instances of URI (Python objects), not as strings.
