pyzim.cluster.OffsetRememberingCluster

class documentation

class OffsetRememberingCluster(Cluster):

Known subclasses: pyzim.cluster.InMemoryCluster

Constructor: OffsetRememberingCluster(zim, offset)

A variation of Cluster that reads offsets only once, storing them in memory.

Method	`__init__`	The default constructor.
Method	`iter_blob_offsets`	Read the blob offsets, yielding them as an iterator.
Method	`reset`	Reset all internal state except the cluster offset, causing said offset to be read again the next time it is required.
Method	`_read_offsets_if_needed`	Read the offsets if they have not yet been read.
Instance Variable	`_offsets`	the offsets in this cluster

Inherited from Cluster:

Method	`generate_infobyte`	Generate the infobyte for this cluster.
Method	`get_blob_size`	Get the size of a blob.
Method	`get_content_size`	Return the content size of this cluster.
Method	`get_number_of_blobs`	Return the number of blobs in this cluster.
Method	`get_number_of_offsets`	Return the number of offsets in this cluster.
Method	`get_offset`	Return the offset with the specified index.
Method	`get_total_compressed_size`	Return the total compressed size of the cluster.
Method	`get_total_decompressed_size`	Return the total decompressed size of this cluster.
Method	`get_total_offset_size`	Return the total size of the offsets.
Method	`iter_read_blob`	Iteratively read the specified blob.
Method	`parse_infobyte`	Parse the cluster information byte, setting the attributes of this cluster as necessary.
Method	`read_blob`	Read the entirety of the specified range in the specified blob and return the content.
Method	`read_infobyte`	Read the cluster information byte, returning it.
Method	`read_infobyte_if_needed`	Read and parse the infobyte if this has not yet happened.
Instance Variable	`compression`	compression to use, None when unknown
Instance Variable	`is_extended`	whether this cluster is extended, None if not set
Instance Variable	`offset`	absolute offset of the cluster
Property	`did_read_infobyte`	True if the infobyte was already read and parsed.
Method	`_get_compressor`	Return a compressor suitable to compress this cluster.
Method	`_get_decompressing_reader`	Return a decompressing reader that can be sued to decompress the content.
Method	`_get_decompressor`	Return a decompressor suitable to decompress this cluster.
Method	`_seek_if_needed`	Seek to the specified position (relative to the cluster start) in the file only if it is needed.
Instance Variable	`_decompressing_reader`	Undocumented
Property	`_pointer_format`	The pointer format.

Inherited from BindableMixIn (via Cluster):

Method	`bind`	Bind this object to a ZIM file.
Method	`unbind`	Unbind this object. Can be called multiple times.
Property	`bound`	Whether this object is bound to a ZIM file or not.
Property	`zim`	The bound ZIM archive, if any is bound. Otherwise None.
Instance Variable	`_zim`	the bound ZIM archive or None

def __init__(self, zim=None, offset=None): ¶

overrides pyzim.cluster.Cluster.__init__

overridden in pyzim.cluster.InMemoryCluster

The default constructor.

Parameters
zim:`pyzim.archive.Zim`	if specified, bind this ZIM immediately.
offset:`int` or `None`	absolute offset of the cluster

Raises
`ValueError`	if offset was specified but zim was not specified.

def iter_blob_offsets(self, blob_numbers=None): ¶

overrides pyzim.cluster.Cluster.iter_blob_offsets

Read the blob offsets, yielding them as an iterator.

The order of blob_numbers does not matter, all offsets are always yielded in regular order (offfset 1, offset 2, ...).

Parameters
blob_numbers:`None` or `list` of `int`	if specified, load only these offsets

Yields
`int`	the offset of each blob in the decompressed body, relative to cluster start

Raises
`pyzim.exceptions.BindRequired`	if cluster is unbound

def reset(self): ¶

overrides pyzim.cluster.Cluster.reset

overridden in pyzim.cluster.InMemoryCluster

Reset all internal state except the cluster offset, causing said offset to be read again the next time it is required.

def _read_offsets_if_needed(self): ¶

Read the offsets if they have not yet been read.

Raises
`pyzim.exceptions.BindRequired`	if cluster is unbound

_offsets: list of int = ¶

the offsets in this cluster