feat: run multiple jobs in parallel

tests/job-definitions/job-definitions.yaml

@@ -124,3 +124,11 @@ jobs:
   cluster-butina:
     command: >-
       addcol.py --inputFile {{ inputFile }} --outputFile {{ outputFile }} --name {{ name }} --value {{ value }}
+
+  append-col:
+    command: >-
+      addcol2.py --inputFile {{ inputFile }} --outputFile {{ outputFile }} --name {{ name }} --value {{ value }}
+
+  concatenate:
+    command: >-
+      concatenate.py {% for ifile in  inputFile %}{{ ifile }} {% endfor %} --outputFile {{ outputFile }}

tests/jobs/addcol2.py

@@ -0,0 +1,18 @@
+import argparse
+
+parser = argparse.ArgumentParser(
+    prog="addcol",
+    description="Takes a SMILES string and writes it to a file",
+)
+parser.add_argument("-i", "--inputFile", required=True)
+parser.add_argument("-o", "--outputFile", required=True)
+parser.add_argument("-n", "--name", required=True)
+parser.add_argument("-v", "--value", required=True)
+args = parser.parse_args()
+
+with (
+    open(args.inputFile, "rt", encoding="utf8") as ifile,
+    open(args.outputFile, "wt", encoding="utf8") as ofile,
+):
+    for line in ifile.read().splitlines():
+        ofile.write(f"{line}\t{args.value}\n")

tests/jobs/concatenate.py

@@ -0,0 +1,14 @@
+import argparse
+
+parser = argparse.ArgumentParser(
+    prog="addcol",
+    description="Takes a list of files and writes them into single outputfile",
+)
+parser.add_argument("inputFile", nargs="+", type=argparse.FileType("r"))
+parser.add_argument("-o", "--outputFile", required=True)
+args = parser.parse_args()
+
+
+with open(args.outputFile, "wt", encoding="utf8") as ofile:
+    for f in args.inputFile:
+        ofile.write(f.read())

tests/test_workflow_engine_examples.py

@@ -399,3 +399,52 @@ def test_workflow_engine_simple_python_molprops_with_options(basic_engine):
     # This test should generate a file in the simulated project directory
     assert project_file_exists(output_file_1)
     assert project_file_exists(output_file_2)
+
+
+def test_workflow_engine_simple_python_parallel(basic_engine):
+    # Arrange
+    da, md = basic_engine
+    # Make sure files that should be generated by the test
+    # do not exist before we run the test.
+    output_file_first = "first-step.out.smi"
+    assert not project_file_exists(output_file_first)
+    output_file_pa = "parallel-step-a.out.smi"
+    assert not project_file_exists(output_file_pa)
+    output_file_pb = "parallel-step-b.out.smi"
+    assert not project_file_exists(output_file_pb)
+    output_file_final = "final-step.out.smi"
+    assert not project_file_exists(output_file_final)
+    # And create the test's input file.
+    input_file_1 = "input1.smi"
+    input_file_1_content = "O=C(CSCc1ccc(Cl)s1)N1CCC(O)CC1"
+    with open(
+        f"{EXECUTION_DIRECTORY}/{input_file_1}", mode="wt", encoding="utf8"
+    ) as input_file:
+        input_file.writelines(input_file_1_content)
+
+    # Act
+    r_wfid = start_workflow(
+        md,
+        da,
+        "simple-python-parallel",
+        {"candidateMolecules": input_file_1},
+    )
+
+    # Assert
+    wait_for_workflow(da, r_wfid)
+    # Additional, detailed checks...
+    # Check we only have one RunningWorkflowStep, and it succeeded
+    response = da.get_running_workflow_steps(running_workflow_id=r_wfid)
+
+    assert response["count"] == 4
+    assert response["running_workflow_steps"][0]["done"]
+    assert response["running_workflow_steps"][0]["success"]
+    assert response["running_workflow_steps"][1]["done"]
+    assert response["running_workflow_steps"][1]["success"]
+    assert response["running_workflow_steps"][2]["done"]
+    assert response["running_workflow_steps"][2]["success"]
+    assert response["running_workflow_steps"][3]["done"]
+    assert response["running_workflow_steps"][3]["success"]
+    # This test should generate a file in the simulated project directory
+    assert project_file_exists(output_file_first)
+    assert project_file_exists(output_file_final)

tests/workflow-definitions/shortcut-example-1.yaml

@@ -25,7 +25,7 @@ steps:
   inputs:
   - input: 'inputFile'
     from:
-      step: step-1
+      step: example-1-step-1
       output: 'outputFile'
   outputs:
   - output: 'outputFile'

tests/workflow-definitions/simple-python-parallel.yaml

@@ -0,0 +1,90 @@
+---
+kind: DataManagerWorkflow
+kind-version: "2024.1"
+name: python-workflow
+description: A simple branching workflow
+variables:
+  inputs:
+  - name: candidateMolecules
+    type: squonk/x-smiles
+  outputs:
+  - name: clusteredMolecules
+    from:
+      step: final-step
+      output: outputFile
+    as: clustered-molecules.smi
+
+
+steps:
+
+- name: first-step
+  description: Create inputs
+  specification:
+    collection: workflow-engine-unit-test-jobs
+    job: rdkit-molprops
+    version: "1.0.0"
+    variables:
+      name: "unnecessary"
+      value: "0"
+  inputs:
+  - input: inputFile
+    from:
+      workflow-input: candidateMolecules
+  outputs:
+  - output: outputFile
+    as: first-step.out.smi
+
+- name: parallel-step-a
+  description: Add some params
+  specification:
+    collection: workflow-engine-unit-test-jobs
+    job: append-col
+    version: "1.0.0"
+    variables:
+      name: "desc1"
+      value: "777"
+  inputs:
+  - input: inputFile
+    from:
+      step: first-step
+      output: outputFile
+  outputs:
+  - output: outputFile
+    as: parallel-step-a.out.smi
+
+- name: parallel-step-b
+  description: Add some other params
+  specification:
+    collection: workflow-engine-unit-test-jobs
+    job: append-col
+    version: "1.0.0"
+    variables:
+      name: "desc2"
+      value: "999"
+  inputs:
+  - input: inputFile
+    from:
+      step: first-step
+      output: outputFile
+  outputs:
+  - output: outputFile
+    as: parallel-step-b.out.smi
+
+- name: final-step
+  description: Collate results
+  specification:
+    collection: workflow-engine-unit-test-jobs
+    job: concatenate
+    version: "1.0.0"
+  inputs:
+  - input: inputFile
+    from:
+      step: parallel-step-a
+      output: outputFile
+  - input: inputFile
+    from:
+      step: parallel-step-b
+      output: outputFile
+  outputs:
+  - output: outputFile
+    as: final-step.out.smi

workflow/decoder.py

@@ -170,13 +170,23 @@ def set_step_variables(
         val = item["from"]
         if "workflow-input" in val.keys():
             p_val = workflow_variables[val["workflow-input"]]
+            result[p_key] = p_val
         elif "step" in val.keys():
             for out in previous_step_outputs:
                 if out["output"] == val["output"]:
                     p_val = out["as"]
-                    break
 
-        result[p_key] = p_val
+                    # this bit handles multiple inputs: if a step
+                    # requires input from multiple steps, add them to
+                    # the list in result dict. this is the reason for
+                    # mypy ignore statements, mypy doesn't understand
+                    # redefinition
+                    if p_key in result:
+                        if not isinstance(result[p_key], set):
+                            result[p_key] = {result[p_key]}  # type: ignore [assignment]
+                        result[p_key].add(p_val)  # type: ignore [attr-defined]
+                    else:
+                        result[p_key] = p_val
 
     for item in outputs:
         p_key = item["output"]
@@ -191,4 +201,6 @@ def set_step_variables(
 
     result |= options
 
+    print("final step vars", result)
+
     return result

workflow/workflow_engine.py

@@ -369,8 +369,15 @@ def _validate_step_command(
         )
 
         if our_index > 0:
-            previous_step = wf_step_data["steps"][our_index - 1]
-            previous_step_outputs = previous_step.get("outputs", [])
+            # resolve all previous steps
+            previous_step_names = set()
+            for inp in inputs:
+                if step_name := inp["from"].get("step", None):
+                    previous_step_names.add(step_name)
+
+            for step in wf_step_data["steps"]:
+                if step["name"] in previous_step_names:
+                    previous_step_outputs.extend(step.get("outputs", []))
 
         _LOGGER.debug(
             "Index %s (%s) workflow_variables=%s",