interfaces.py: remove get_extension_params and set_extension_params methods from...

[tahoe-lafs/tahoe-lafs.git] / src / allmydata / interfaces.py

diff --git a/src/allmydata/interfaces.py b/src/allmydata/interfaces.py
index 3081e94e2fdf7fe65d8911798072bea6eeccc2c1..a8b118025f4b88cb94ac60e801f06ee8cd130c12 100644 (file)
--- a/src/allmydata/interfaces.py
+++ b/src/allmydata/interfaces.py
@@ -148,21 +148,6 @@ class RIStorageServer(RemoteInterface):
         """
         return Any()
 
-    def cancel_lease(storage_index=StorageIndex,
-                     cancel_secret=LeaseCancelSecret):
-        """
-        Cancel the lease on a given bucket. If this was the last lease on the
-        bucket, the bucket will be deleted. If there is no bucket for the
-        given storage_index, IndexError will be raised.
-
-        For mutable shares, if the given cancel_secret does not match an
-        existing lease, IndexError will be raised with a note listing the
-        server-nodeids on the existing leases, so leases on migrated shares
-        can be renewed or cancelled. For immutable shares, IndexError
-        (without the note) will be raised.
-        """
-        return Any()
-
     def get_buckets(storage_index=StorageIndex):
         return DictOf(int, RIBucketReader, maxKeys=MAX_BUCKETS)
 
@@ -224,12 +209,35 @@ class RIStorageServer(RemoteInterface):
         necessary. A write vector applied to a share number that did not
         exist previously will cause that share to be created.
 
-        Each write vector is accompanied by a 'new_length' argument. If
-        new_length is not None, use it to set the size of the container. This
-        can be used to pre-allocate space for a series of upcoming writes, or
-        truncate existing data. If the container is growing, new_length will
-        be applied before datav. If the container is shrinking, it will be
-        applied afterwards. If new_length==0, the share will be deleted.
+        In Tahoe-LAFS v1.8.3 or later (except 1.9.0a1), if you send a write
+        vector whose offset is beyond the end of the current data, the space
+        between the end of the current data and the beginning of the write
+        vector will be filled with zero bytes. In earlier versions the
+        contents of this space was unspecified (and might end up containing
+        secrets). Storage servers with the new zero-filling behavior will
+        advertise a true value for the 'fills-holes-with-zero-bytes' key
+        (under 'http://allmydata.org/tahoe/protocols/storage/v1') in their
+        version information.
+
+        Each write vector is accompanied by a 'new_length' argument, which
+        can be used to truncate the data. If new_length is not None and it is
+        less than the current size of the data (after applying all write
+        vectors), then the data will be truncated to new_length. If
+        new_length==0, the share will be deleted.
+
+        In Tahoe-LAFS v1.8.2 and earlier, new_length could also be used to
+        enlarge the file by sending a number larger than the size of the data
+        after applying all write vectors. That behavior was not used, and as
+        of Tahoe-LAFS v1.8.3 it no longer works and the new_length is ignored
+        in that case.
+
+        If a storage client knows that the server supports zero-filling, for
+        example from the 'fills-holes-with-zero-bytes' key in its version
+        information, it can extend the file efficiently by writing a single
+        zero byte just before the new end-of-file. Otherwise it must
+        explicitly write zeroes to all bytes between the old and new
+        end-of-file. In any case it should avoid sending new_length larger
+        than the size of the data after applying all write vectors.
 
         The read vector is used to extract data from all known shares,
         *before* any writes have been applied. The same vector is used for
@@ -449,7 +457,7 @@ class IMutableSlotWriter(Interface):
         Add a block and salt to the share.
         """
 
-    def put_encprivey(encprivkey):
+    def put_encprivkey(encprivkey):
         """
         Add the encrypted private key to the share.
         """
@@ -542,12 +550,7 @@ class IImmutableFileURI(IFileURI):
     pass
 
 class IMutableFileURI(Interface):
-    """I am a URI which represents a mutable filenode."""
-    def get_extension_params():
-        """Return the extension parameters in the URI"""
-
-    def set_extension_params():
-        """Set the extension parameters that should be in the URI"""
+    pass
 
 class IDirectoryURI(Interface):
     pass
@@ -1055,6 +1058,9 @@ class NotEnoughSharesError(Exception):
 class NoSharesError(Exception):
     """Download was unable to get any shares at all."""
 
+class DownloadStopped(Exception):
+    pass
+
 class UploadUnhappinessError(Exception):
     """Upload was unable to satisfy 'servers_of_happiness'"""