#! /usr/bin/env python
"""
Save and load MinHash sketches in a JSON format, along with some metadata.
"""
import sys
import os
import weakref
from enum import Enum
import contextlib
from .logging import error
from . import MinHash
from .minhash import to_bytes, FrozenMinHash
from ._lowlevel import ffi, lib
from .utils import RustObject, rustcall, decode_str
SIGNATURE_VERSION = 0.4
[docs]class SourmashSignature(RustObject):
"Main class for signature information."
__dealloc_func__ = lib.signature_free
def __init__(self, minhash, name="", filename=""):
self._objptr = lib.signature_new()
if name:
self.name = name
if filename:
self.filename = filename
self.minhash = minhash
@property
def minhash(self):
return FrozenMinHash._from_objptr(
self._methodcall(lib.signature_first_mh)
)
@minhash.setter
def minhash(self, value):
# TODO: validate value is a MinHash
self._methodcall(lib.signature_set_mh, value._objptr)
def __hash__(self):
return hash(self.md5sum())
def __str__(self):
return self._display_name()
def __repr__(self):
name = self.name
md5pref = self.md5sum()[:8]
if name == md5pref:
return "SourmashSignature({})".format(md5pref)
else: # name != md5pref:
return "SourmashSignature('{}', {})".format(name, md5pref)
#def minhashes(self):
# size = ffi.new("uintptr_t *")
# mhs_ptr = self._methodcall(lib.signature_get_mhs, size)
# size = ffi.unpack(size, 1)[0]
#
# mhs = []
# for i in range(size):
# mh = MinHash._from_objptr(mhs_ptr[i])
# mhs.append(mh)
#
# return mhs
[docs] def md5sum(self):
"Calculate md5 hash of the bottom sketch, specifically."
return decode_str(self.minhash._methodcall(lib.kmerminhash_md5sum))
def __eq__(self, other):
return self._methodcall(lib.signature_eq, other._objptr)
@property
def _name(self):
return decode_str(self._methodcall(lib.signature_get_name))
@_name.setter
def _name(self, value):
self._methodcall(lib.signature_set_name, to_bytes(value))
@property
def name(self):
return decode_str(self._methodcall(lib.signature_get_name))
@name.setter
def name(self, value):
self._methodcall(lib.signature_set_name, to_bytes(value))
def __ne__(self, other):
return not self == other
@property
def filename(self):
return decode_str(self._methodcall(lib.signature_get_filename))
@filename.setter
def filename(self, value):
self._methodcall(lib.signature_set_filename, to_bytes(value))
@property
def license(self):
return decode_str(self._methodcall(lib.signature_get_license))
def _display_name(self, max_length=0):
name = self._name
filename = self.filename
if name:
if max_length and len(name) > max_length:
name = name[: max_length - 3] + "..."
elif filename:
name = filename
if max_length and len(name) > max_length:
name = "..." + name[-max_length + 3 :]
else:
name = self.md5sum()[:8]
assert not max_length or len(name) <= max_length
return name
[docs] def similarity(self, other, ignore_abundance=False, downsample=False):
"Compute similarity with the other signature."
return self.minhash.similarity(other.minhash,
ignore_abundance=ignore_abundance,
downsample=downsample)
[docs] def jaccard(self, other):
"Compute Jaccard similarity with the other MinHash signature."
return self.minhash.similarity(other.minhash, ignore_abundance=True,
downsample=False)
[docs] def jaccard_ani(self, other, *, downsample=False, jaccard=None, prob_threshold=1e-3, err_threshold=1e-4):
"Use jaccard to estimate ANI between two FracMinHash signatures."
return self.minhash.jaccard_ani(other.minhash, downsample=downsample,
jaccard=jaccard, prob_threshold=prob_threshold,
err_threshold=err_threshold)
[docs] def contained_by(self, other, downsample=False):
"Compute containment by the other signature. Note: ignores abundance."
return self.minhash.contained_by(other.minhash, downsample=downsample)
[docs] def containment_ani(self, other, *, downsample=False, containment=None, confidence=0.95, estimate_ci=False):
"Use containment to estimate ANI between two FracMinHash signatures."
return self.minhash.containment_ani(other.minhash, downsample=downsample,
containment=containment, confidence=confidence,
estimate_ci=estimate_ci)
[docs] def max_containment(self, other, downsample=False):
"Compute max containment w/other signature. Note: ignores abundance."
return self.minhash.max_containment(other.minhash, downsample=downsample)
[docs] def max_containment_ani(self, other, *, downsample=False, max_containment=None, confidence=0.95, estimate_ci=False):
"Use max containment to estimate ANI between two FracMinHash signatures."
return self.minhash.max_containment_ani(other.minhash, downsample=downsample,
max_containment=max_containment, confidence=confidence,
estimate_ci=estimate_ci)
[docs] def avg_containment(self, other, downsample=False):
"""
Calculate average containment.
Note: this is average of the containments, *not* count_common/ avg_denom
"""
return self.minhash.avg_containment(other.minhash, downsample=downsample)
[docs] def avg_containment_ani(self, other, *, downsample=False):
"""
Calculate average containment ANI.
Note: this is average of the containment ANI's, *not* ANI using count_common/ avg_denom
"""
return self.minhash.avg_containment_ani(other.minhash, downsample=downsample)
def add_sequence(self, sequence, force=False):
self._methodcall(lib.signature_add_sequence, to_bytes(sequence), force)
def add_protein(self, sequence):
self._methodcall(lib.signature_add_protein, to_bytes(sequence))
@staticmethod
def from_params(params):
ptr = rustcall(lib.signature_from_params, params._get_objptr())
return SourmashSignature._from_objptr(ptr)
def __len__(self):
return self._methodcall(lib.signature_len)
def __getstate__(self): # enable pickling
return (
self.minhash,
self.name,
self.filename,
)
def __setstate__(self, tup):
(mh, name, filename) = tup
self.__del__()
self._objptr = lib.signature_new()
if name:
self.name = name
if filename:
self.filename = filename
self.minhash = mh
def __reduce__(self):
return (
SourmashSignature,
(
self.minhash,
self.name,
self.filename
),
)
def __copy__(self):
a = SourmashSignature(
self.minhash,
name=self.name,
filename=self.filename,
)
return a
copy = __copy__
[docs] def to_frozen(self):
"Return a frozen copy of this signature."
new_ss = self.copy()
new_ss.__class__ = FrozenSourmashSignature
return new_ss
[docs] def to_mutable(self):
"Return a mutable copy of this signature."
return self.copy()
[docs] def into_frozen(self):
"Freeze this signature, preventing attribute changes."
# this will always be the case b/c minhash property returns FrozenMH:
# assert isinstance(self.minhash, FrozenMinHash)
self.__class__ = FrozenSourmashSignature
[docs]class FrozenSourmashSignature(SourmashSignature):
"Frozen (immutable) signature class."
@SourmashSignature.minhash.setter
def minhash(self, value):
raise ValueError("cannot set .minhash on FrozenSourmashSignature")
@SourmashSignature._name.setter
def _name(self, value):
raise ValueError("cannot set ._name on FrozenSourmashSignature")
@SourmashSignature.name.setter
def name(self, value):
raise ValueError("cannot set .name on FrozenSourmashSignature")
@SourmashSignature.filename.setter
def filename(self, value):
raise ValueError("cannot set .filename on FrozenSourmashSignature")
def add_sequence(self, sequence, force=False):
raise ValueError("cannot add sequence data to FrozenSourmashSignature")
def add_protein(self, sequence):
raise ValueError("cannot add protein sequence to FrozenSourmashSignature")
def __copy__(self):
return self
copy = __copy__
[docs] def to_frozen(self):
"Return a frozen copy of this signature."
return self
[docs] def to_mutable(self):
"Turn this object into a mutable object."
mut = SourmashSignature.__new__(SourmashSignature)
state_tup = self.__getstate__()
mut.__setstate__(state_tup)
return mut
[docs] def into_frozen(self):
"Freeze this signature, preventing attribute changes."
self.__class__ = FrozenSourmashSignature
[docs] @contextlib.contextmanager
def update(self):
"""Make a mutable copy of this signature for modification, then freeze.
This is a context manager that implements:
new_sig = this_sig.copy()
new_sig.to_mutable()
# modify new_sig
new_sig.into_frozen()
This could be made more efficient by _not_ copying the signature,
but that is non-intuitive and leads to hard-to-find bugs.
"""
new_copy = self.to_mutable()
yield new_copy
new_copy.into_frozen()
def _detect_input_type(data):
"""\
Determine how to load input from `data`. Returns SigInput enum.
Checks for:
- Python file-like objects
- JSON text (uncompressed sigs)
- Compressed memory buffers
- filename
"""
if hasattr(data, 'read') or hasattr(data, "fileno") or hasattr(data, "mode"): # file-like object
return SigInput.FILE_LIKE
elif hasattr(data, "find"): # check if it is uncompressed sig
try:
if data.find("sourmash_signature") > 0:
return SigInput.BUFFER
except TypeError:
if data.find(b"sourmash_signature") > 0:
return SigInput.BUFFER
elif data.startswith(b'\x1F\x8B'): # gzip compressed
return SigInput.BUFFER
try:
if os.path.exists(data): # filename
return SigInput.PATH
except (ValueError, TypeError): # No idea...
return SigInput.UNKNOWN
return SigInput.UNKNOWN
[docs]def load_signatures(
data, ksize=None, select_moltype=None, ignore_md5sum=False, do_raise=False,
):
"""Load a JSON string with signatures into classes.
Returns iterator over SourmashSignature objects.
Note, the order is not necessarily the same as what is in the source file.
"""
if ksize is not None:
ksize = int(ksize)
else:
ksize = 0
if not data:
return
if select_moltype is None:
select_moltype = ffi.NULL
else:
try:
select_moltype = select_moltype.encode("utf-8")
except AttributeError:
pass
input_type = _detect_input_type(data)
if input_type == SigInput.UNKNOWN:
if do_raise:
raise ValueError("Error in parsing signature; quitting. Cannot open file or invalid signature")
return
size = ffi.new("uintptr_t *")
try:
if input_type == SigInput.FILE_LIKE:
if hasattr(data, "mode") and "t" in data.mode: # need to reopen handler as binary
data = data.buffer
buf = data.read()
data.close()
data = buf
input_type = SigInput.BUFFER
elif input_type == SigInput.PATH:
sigs_ptr = rustcall(
lib.signatures_load_path,
data.encode("utf-8"),
ignore_md5sum,
ksize,
select_moltype,
size,
)
if input_type == SigInput.BUFFER:
if hasattr(data, "encode"):
data = data.encode("utf-8")
sigs_ptr = rustcall(
lib.signatures_load_buffer,
data,
len(data),
ignore_md5sum,
ksize,
select_moltype,
size,
)
size = size[0]
sigs = []
for i in range(size):
sig = SourmashSignature._from_objptr(sigs_ptr[i])
sigs.append(sig)
for sig in sigs:
yield sig.to_frozen()
except Exception as e:
if do_raise:
raise
def load_one_signature(data, ksize=None, select_moltype=None, ignore_md5sum=False):
sigiter = load_signatures(
data, ksize=ksize, select_moltype=select_moltype, ignore_md5sum=ignore_md5sum
)
try:
first_sig = next(sigiter)
except StopIteration:
raise ValueError("no signatures to load")
try:
next(sigiter)
except StopIteration:
return first_sig
raise ValueError("expected to load exactly one signature")
[docs]def save_signatures(siglist, fp=None, compression=0):
"Save multiple signatures into a JSON string (or into file handle 'fp')"
attached_refs = weakref.WeakKeyDictionary()
# get list of rust objects
collected = []
for obj in siglist:
rv = obj._get_objptr()
attached_refs[rv] = obj
collected.append(rv)
siglist_c = ffi.new("SourmashSignature*[]", collected)
size = ffi.new("uintptr_t *")
# save signature into a string (potentially compressed)
rawbuf = rustcall(lib.signatures_save_buffer, siglist_c, len(collected),
compression, size)
size = size[0]
# associate a finalizer with rawbuf so that it gets freed
buf = ffi.gc(rawbuf, lambda o: lib.nodegraph_buffer_free(o, size), size)
if compression:
result = ffi.buffer(buf, size)[:]
else:
result = ffi.string(buf, size)
if fp is None: # return string
return result
else:
try: # write to file
fp.write(result)
except TypeError:
fp.write(result.decode('utf-8'))
return None
