Node codecs

exception larch.codec.CodecError(msg)
class larch.codec.NodeCodec(key_bytes)

Encode and decode nodes from their binary format.

Node identifiers are assumed to fit into 64 bits.

Leaf node values are assumed to fit into 4 gibibytes.

decode(encoded)
Decode node of any type.
decode_index(encoded)
Decode an index node from its encoded byte string.
decode_leaf(encoded)
Decode a leaf node from its encoded byte string.
encode(node)
Encode a node of any type.
encode_index(node)
Encode an index node as a byte string.
encode_leaf(node)
Encode a leaf node as a byte string.
index_size(keys, values)
Return size of an index node with the given pairs.
leaf_size(keys, values)
Return size of a leaf node with the given pairs.
leaf_size_delta_add(old_size, value)

Return size of node that gets a new key/value pair added.

old_size is the old size of the node. The key must not already have existed in the node.

leaf_size_delta_replace(old_size, old_value, new_value)
Return size of node that gets a value replaced.
max_index_pairs(node_size)
Return number of index pairs that fit in a node of a given size.
size(node)
Return encoded size of a node, regardless of type.

Previous topic

Individual nodes

Next topic

Node storage

This Page