Merge pull request #49 from simleo/engine_traces

Add recommendation on adding workflow traces

docs/profiles/0.1-DRAFT/workflow_run_crate.md

@@ -208,6 +208,32 @@ Additional properties described in the [Bioschemas FormalParameter profile](http
 ```
 
 
+## Adding engine-specific traces
+
+Some engines are able to generate contextual information about workflow runs in the form of logs, reports, etc. These are not workflow outputs, but rather additional files automatically generated by the engine, either by default or when activated via a configuration parameter or command line flag. It is RECOMMENDED to add any such files to the RO-Crate; the corresponding entities SHOULD refer to the relevant `Action` instance via [about](http://schema.org/about):
+
+```json
+{
+    "@id": "#action-1",
+    "@type": "CreateAction",
+    ...
+},
+{
+    "@id": "trace-20230120-40360336.txt",
+    "@type": "File",
+    "name": "Nextflow trace for action-1",
+    "conformsTo": "https://www.nextflow.io/docs/latest/tracing.html#trace-report",
+    "encodingFormat": "text/tab-separated-values",
+    "about": "#action-1"
+},
+{
+    "@id": "https://www.nextflow.io/docs/latest/tracing.html#trace-report",
+    "@type": "CreativeWork",
+    "name": "Nextflow trace report CSV profile"
+}
+```
+
+
 ## Requirements
 
 This profile inherits the requirements of [Process Run Crate](process_run_crate) and [Workflow RO-Crate](https://w3id.org/workflowhub/workflow-ro-crate/). In particular, the entity acting as the `instrument` of the `CreateAction` MUST be the *main workflow*. This and other additional specifications are listed below.