BWA-MEM2 INDEX

Creates a bwa-mem2 index.

Example

This wrapper can be used in the following way:

rule bwa_mem2_index:
    input:
        "{genome}",
    output:
        "{genome}.0123",
        "{genome}.amb",
        "{genome}.ann",
        "{genome}.bwt.2bit.64",
        "{genome}.pac",
    log:
        "logs/bwa-mem2_index/{genome}.log",
    wrapper:
        "v1.9.0/bio/bwa-mem2/index"

Note that input, output and log file paths can be chosen freely.

When running with

snakemake --use-conda

the software dependencies will be automatically deployed into an isolated environment before execution.

Software dependencies

• bwa-mem2==2.2.1

Authors

• Christopher Schröder
• Patrik Smeds

Code

__author__ = "Christopher Schröder, Patrik Smeds"
__copyright__ = "Copyright 2020, Christopher Schröder, Patrik Smeds"
__email__ = "christopher.schroeder@tu-dortmund.de, patrik.smeds@gmail.com"
__license__ = "MIT"

from os import path

from snakemake.shell import shell

log = snakemake.log_fmt_shell(stdout=False, stderr=True)

# Check inputs/arguments.
if len(snakemake.input) == 0:
    raise ValueError("A reference genome has to be provided.")
elif len(snakemake.input) > 1:
    raise ValueError("Please provide exactly one reference genome as input.")

valid_suffixes = {".0123", ".amb", ".ann", ".bwt.2bit.64", ".pac"}


def get_valid_suffix(path):
    for suffix in valid_suffixes:
        if path.endswith(suffix):
            return suffix


prefixes = set()
for s in snakemake.output:
    suffix = get_valid_suffix(s)
    if suffix is None:
        raise ValueError(f"{s} cannot be generated by bwa-mem2 index (invalid suffix).")
    prefixes.add(s[: -len(suffix)])

if len(prefixes) != 1:
    raise ValueError("Output files must share common prefix up to their file endings.")
(prefix,) = prefixes

shell("bwa-mem2 index -p {prefix} {snakemake.input[0]} {log}")