如何在 snakemake 运行 指令下传递函数

how to pass a function under snakemake run directive

我正在 snakemake 中构建一个工作流,并希望将其中一个规则回收到两个不同的输入源。输入源可以是 source1 或 source1+source2,并且根据输入,输出目录也会有所不同。由于在同一规则中执行此操作非常复杂,而且我不想创建完整规则的副本,因此我想创建两个具有不同 input/output 但 运行 相同命令的规则。

有可能使这项工作吗?我正确解析了 DAG,但作业没有在集群上完成 (ERROR : bamcov_cmd not defined).. 下面的示例(两个规则最后使用相同的命令):

这是命令

def bamcov_cmd():
return( (deepTools_path+"bamCoverage " +
            "-b {input.bam} " +
            "-o {output} " +
            "--binSize {params.bw_binsize} " +
            "-p {threads} " +
            "--normalizeTo1x {params.genome_size} " +
            "{params.read_extension} " +
            "&> {log}") )

这是规则

rule bamCoverage:
input:
    bam = file1+"/{sample}.bam",
    bai = file1+"/{sample}.bam.bai"
output:
    "bamCoverage/{sample}.filter.bw"
params:
    bw_binsize = bw_binsize,
    genome_size = int(genome_size),
    read_extension = "--extendReads"
log:
    "bamCoverage/logs/bamCoverage.{sample}.log"
benchmark:
    "bamCoverage/.benchmark/bamCoverage.{sample}.benchmark"
threads: 16
run:
    bamcov_cmd()

这是可选规则2

rule bamCoverage2:
input:
    bam = file2+"/{sample}.filter.bam",
    bai = file2+"/{sample}.filter.bam.bai"
output:
    "bamCoverage/{sample}.filter.bw"
params:
    bw_binsize = bw_binsize,
    genome_size = int(genome_size),
    read_extension = "--extendReads"
log:
    "bamCoverage/logs/bamCoverage.{sample}.log"
benchmark:
    "bamCoverage/.benchmark/bamCoverage.{sample}.benchmark"
threads: 16
run:
    bamcov_cmd()

你问的在python中是可能的。 这取决于文件中是否只有 python 代码,或者 python 和 Snakemake。 我会先回答这个问题,然后我会进行跟进回复,因为我希望您进行不同的设置,这样您就不必这样做了。

就Python:

 from fileContainingMyBamCovCmdFunction import bamcov_cmd

 rule bamCoverage:
 ...
     run:
         bamcov_cmd()

在视觉上,看看我在这个文件中是如何做的,以引用对 buildHeader 和 buildSample 的访问。这些文件被 Snakefile 调用。它应该对你有用。 https://github.com/LCR-BCCRC/workflow_exploration/blob/master/Snakemake/modules/py_buildFile/buildFile.py

编辑 2017-07-23 - 更新下面的代码段以反映用户评论

Snakemake 和 Python:

 include: "fileContainingMyBamCovCmdFunction.suffix"

 rule bamCoverage:
 ...
     run:
         shell(bamcov_cmd())

编辑结束

如果函数确实特定于 bamCoverage 调用,如果您愿意,可以将其放回规则中。这意味着它没有在其他地方被调用,这可能是真的。 使用“.”注释文件时要小心符号,我使用'_'因为我发现以这种方式防止创建循环依赖更容易。 此外,如果您最终将这两个规则分开,您很可能会遇到歧义错误。 http://snakemake.readthedocs.io/en/latest/snakefiles/rules.html?highlight=ruleorder#handling-ambiguous-rules 如果可能,最好的做法是让规则生成唯一的输出。

至于替代方案,考虑像这样设置代码吗?

from subprocess import call


rule all:
    input:
          "path/to/file/mySample.bw"
          #OR
          #"path/to/file/mySample_filtered.bw"


bamCoverage:
input:
    bam = file1+"/{sample}.bam",
    bai = file1+"/{sample}.bam.bai"
output:
    "bamCoverage/{sample}.bw"
params:
    bw_binsize = bw_binsize,
    genome_size = int(genome_size),
    read_extension = "--extendReads"
log:
    "bamCoverage/logs/bamCoverage.{sample}.log"
benchmark:
    "bamCoverage/.benchmark/bamCoverage.{sample}.benchmark"
threads: 16
run:
    callString= deepTools_path + "bamCoverage " \
            + "-b " + wilcards.input.bam \
            + "-o " + wilcards.output \
            + "--binSize " str(params.bw_binsize) \
            + "-p " + str({threads}) \
            + "--normalizeTo1x " + str(params.genome_size) \
            + " " + str(params.read_extension) \
            + "&> " + str(log)
    call(callString, shell=True)


rule filterBam:
input:
    "{pathFB}/{sample}.bam"
output:
    "{pathFB}/{sample}_filtered.bam"
run:
    callString="samtools view -bh -F 512 " + wildcards.input \
    + ' > ' + wildcards.output

    call(callString, shell=True)

想法?