StepInput placeholder without key should resolve to $ (aws#7)

* Fixed the placeholder issue when passing the entire step output from previous step to the next step as the input.

Author: andydouglas-exs

src/stepfunctions/inputs/placeholders.py

@@ -132,6 +132,12 @@ def contains(self, placeholder):
  return True
  return False
 
+ def __contains__(self, placeholder):
+ """
+ Containment check operator for placeholder variables.
+ """
+ return self.contains(placeholder)
+
  def validate(self, input):
  """
  Validate a specified input against the placeholder collection schema.

src/stepfunctions/steps/states.py

@@ -701,8 +701,9 @@ def visit(self, state):
 
  def _validate_next_step_params(self, params, step_output):
  for k, v in params.items():
- if isinstance(v, StepInput) and not step_output.contains(v):
- return False, k
+ if isinstance(v, StepInput):
+ if v is not step_output and not step_output.contains(v):
+ return False, k
  elif isinstance(v, dict):
  valid, invalid_param_name = self._validate_next_step_params(v, step_output)
  if not valid:

tests/unit/test_placeholders_with_steps.py

@@ -24,19 +24,21 @@ def test_workflow_input_placeholder():
  state_id='StateOne', 
  parameters={
  'ParamA': 'SampleValueA',
- 'ParamB': workflow_input['Key01'],
- 'ParamC': workflow_input['Key02']['Key03'],
- 'ParamD': workflow_input['Key01']['Key03'],
+ 'ParamB': workflow_input,
+ 'ParamC': workflow_input['Key01'],
+ 'ParamD': workflow_input['Key02']['Key03'],
+ 'ParamE': workflow_input['Key01']['Key03'],
  }
  )
 
  expected_repr = {
  "Type": "Pass",
  "Parameters": {
  "ParamA": "SampleValueA",
- "ParamB.$": "$$.Execution.Input['Key01']",
- "ParamC.$": "$$.Execution.Input['Key02']['Key03']",
- "ParamD.$": "$$.Execution.Input['Key01']['Key03']"
+ "ParamB.$": "$$.Execution.Input",
+ "ParamC.$": "$$.Execution.Input['Key01']",
+ "ParamD.$": "$$.Execution.Input['Key02']['Key03']",
+ "ParamE.$": "$$.Execution.Input['Key01']['Key03']"
  },
  "End": True
  }
@@ -52,16 +54,18 @@ def test_step_input_placeholder():
  test_step_02 = Pass(
  state_id='StateTwo',
  parameters={
- 'ParamA': test_step_01.output()["Response"]["Key02"],
- "ParamB": "SampleValueB"
+ 'ParamA': test_step_01.output(),
+ 'ParamB': test_step_01.output()["Response"]["Key02"],
+ "ParamC": "SampleValueC"
  }
  )
 
  expected_repr = {
  "Type": "Pass",
  "Parameters": {
- "ParamA.$": "$['Response']['Key02']",
- "ParamB": "SampleValueB"
+ "ParamA.$": "$",
+ "ParamB.$": "$['Response']['Key02']",
+ "ParamC": "SampleValueC"
  },
  "End": True
  }
@@ -382,4 +386,4 @@ def test_schema_validation_for_step_input():
  'ParamA': test_step_01.output()["Response"].get("Key01", float),
  "ParamB": "SampleValueB"
  }
- )
+ )

tests/unit/test_placeholders_with_workflows.py

@@ -52,7 +52,8 @@ def workflow(client):
  parameters={
  'ParamG': "SampleValueG",
  "ParamF": execution_input["Key06"],
- "ParamH": "SampleValueH"
+ "ParamH": "SampleValueH",
+ "ParamI": test_step_02.output()
  }
  )