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fix

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Joey Hess 2019-02-20 12:51:50 -04:00
parent d128c8c3ec
commit 5af0876592
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1 changed files with 6 additions and 9 deletions
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15
doc/design/importing_trees_from_special_remotes.mdwn
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@ -128,11 +128,9 @@ This is an extension to the ExportActions api.
listContents :: Annex (Tree [(ExportLocation, ContentIdentifier)])
getContentIdentifier :: ExportLocation -> Annex (Maybe ContentIdentifier)
retrieveExportWithContentIdentifier :: ExportLocation -> ContentIdentifier -> (FilePath -> Annex Key) -> MeterUpdate -> Annex (Maybe Key)
storeExportWithContentIdentifier :: FilePath -> Key -> ExportLocation -> MeterUpdate -> Annex (Maybe ContentIdentifier)
storeExportWithContentIdentifier :: FilePath -> Key -> ExportLocation -> Maybe ContentIdentifier -> MeterUpdate -> Annex (Maybe ContentIdentifier)
listContents finds the current set of files that are stored in the remote,
some of which may have been written by other programs than git-annex,
@ -161,12 +159,11 @@ the content identifier in reply to the store (as S3 does with versioning),
or it can store to a temp location, get the content identifier of that,
and then rename the content into place.
storeExportWithContentIdentifier must avoid overwriting any file that may
have been written to the remote by something else (unless that version of
the file can later be recovered by listContents), so it will typically
need to query for the content identifier before moving the new content
into place. FIXME: How does it know when it's safe to overwrite a file?
Should it be passed the content identifier that it's allowed to overwrite?
storeExportWithContentIdentifier must avoid overwriting any existing file
on the remote, unless the file has the same content identifier that's passed
to it, to avoid overwriting a file that was modified by something else.
But alternatively, if listContents can later recover the modified file, it can
overwrite the modified file.
storeExportWithContentIdentifier needs to handle the case when there's a
race with a concurrent writer. It needs to avoid getting the wrong