Merge pull request #1393 from mahesh-panchal/add_when

Allow conditional process execution from configuration

CHANGELOG.md

@@ -26,6 +26,7 @@
     * `input:` / `output:` not being specified in module
     * Allow for containers from other biocontainers resource as defined [here](https://github.com/nf-core/modules/blob/cde237e7cec07798e5754b72aeca44efe89fc6db/modules/cat/fastq/main.nf#L7-L8)
 * Fixed traceback when using `stageAs` syntax as defined [here](https://github.com/nf-core/modules/blob/cde237e7cec07798e5754b72aeca44efe89fc6db/modules/cat/fastq/main.nf#L11)
+* Allow conditional process execution from the configuration file ([#1393](https://github.com/nf-core/tools/pull/1393))
 
 ## [v2.2 - Lead Liger](https://github.com/nf-core/tools/releases/tag/2.2) - [2021-12-14]
 

nf_core/module-template/modules/main.nf

@@ -5,7 +5,7 @@
 // TODO nf-core: A module file SHOULD only define input and output files as command-line parameters.
 //               All other parameters MUST be provided using the "task.ext" directive, see here:
 //               https://www.nextflow.io/docs/latest/process.html#ext
-//               where "task.ext" is a string. 
+//               where "task.ext" is a string.
 //               Any parameters that need to be evaluated in the context of a particular sample
 //               e.g. single-end/paired-end data MUST also be defined and evaluated appropriately.
 // TODO nf-core: Software that can be piped together SHOULD be added to separate module files
@@ -18,7 +18,7 @@
 process {{ tool_name_underscore|upper }} {
     tag {{ '"$meta.id"' if has_meta else "'$bam'" }}
     label '{{ process_label }}'
-    
+
     // TODO nf-core: List required Conda package(s).
     //               Software MUST be pinned to channel (i.e. "bioconda"), version (i.e. "1.10").
     //               For Conda, the build (i.e. "h9402c20_2") must be EXCLUDED to support installation on different operating systems.
@@ -43,6 +43,9 @@ process {{ tool_name_underscore|upper }} {
     // TODO nf-core: List additional required output channels/values here
     path "versions.yml"           , emit: versions
 
+    when:
+    task.ext.when == null || task.ext.when
+
     script:
     def args = task.ext.args ?: ''
     {% if has_meta -%}