Python models.Link类代码示例

  def insert_end(node, decision):
    """Insert DecisionEnd between node and node parents"""
    parent_links = node.get_parent_links().exclude(name='default')
    decision_end = decision.get_child_end()

    # Find parent decision node for every end's parent.
    # If the decision node is the one passed,
    # change the parent to link to the Decision node's DecisionEnd node.
    # Skip embedded decisions and forks along the way.
    decision_end_used = False
    for parent_link in parent_links:
      parent = parent_link.parent.get_full_node()
      node_temp = parent
      while node_temp and not isinstance(node_temp, Decision):
        if isinstance(node_temp, Join):
          node_temp = node_temp.get_parent_fork().get_parent()
        elif isinstance(node_temp, DecisionEnd):
          node_temp = node_temp.get_parent_decision().get_parent()
        else:
          node_temp = node_temp.get_parent()

      if node_temp.id == decision.id and parent.node_type != Decision.node_type:
        links = Link.objects.filter(parent=parent).exclude(name__in=['related', 'kill', 'error'])
        if len(links) != 1:
          raise RuntimeError(_('Cannot import workflows that have decision DAG leaf nodes with multiple children or no children.'))
        link = links[0]
        link.child = decision_end
        link.save()

        decision_end_used = True

    # Create link between DecisionEnd and terminal node.
    if decision_end_used and not Link.objects.filter(name='to', parent=decision_end, child=node).exists():
      link = Link(name='to', parent=decision_end, child=node)
      link.save()

  def decision_helper(decision, subgraphs):
    """
    Iterates through children, waits for ends.
    When an end is found, finish the decision.
    If the end has more parents than the decision has branches, bubble the end upwards.
    """
    # Create decision end if it does not exist.
    if not Link.objects.filter(parent=decision, name='related').exists():
      end = DecisionEnd(workflow=workflow, node_type=DecisionEnd.node_type)
      end.save()
      link = Link(name='related', parent=decision, child=end)
      link.save()

    children = [_link.child.get_full_node() for _link in decision.get_children_links().exclude(name__in=['error','default'])]

    ends = set()
    for child in children:
      end = helper(child, subgraphs)
      if end:
        ends.add(end)

    # A single end means that we've found a unique end for this decision.
    # Multiple ends mean that we've found a bad decision.
    if len(ends) > 1:
      raise RuntimeError(_('Cannot import workflows that have decisions paths with multiple terminal nodes that converge on a single terminal node.'))
    elif len(ends) == 1:
      end = ends.pop()
      # Branch count will vary with each call if we have multiple decision nodes embedded within decision paths.
      # This is because parents are replaced with DecisionEnd nodes.
      fan_in_count = len(end.get_parent_links().exclude(name__in=['error','default']))
      # IF it covers all branches, then it is an end that perfectly matches this decision.
      # ELSE it is an end for a decision path that the current decision node is a part of as well.
      # The unhandled case is multiple ends for a single decision that converge on a single end.
      # This is not handled in Hue.
      fan_out_count = len(decision.get_children_links().exclude(name__in=['error','default']))
      if fan_in_count > fan_out_count:
        insert_end(end, decision)
        return end
      elif fan_in_count == fan_out_count:
        insert_end(end, decision)
        # End node is a decision node.
        # This means that there are multiple decision nodes in sequence.
        # If both decision nodes are within a single decision path,
        # then the end may need to be returned, if found.
        if isinstance(end, Decision):
          end = decision_helper(end, subgraphs)
          if end:
            return end

        # Can do this because we've replace all its parents with a single DecisionEnd node.
        return helper(end, subgraphs)
      else:
        raise RuntimeError(_('Cannot import workflows that have decisions paths with multiple terminal nodes that converge on a single terminal node.'))
    else:
      raise RuntimeError(_('Cannot import workflows that have decisions paths that never end.'))

    return None

def workflow_save(request, workflow):
    if request.method != "POST":
        raise StructuredException(code="METHOD_NOT_ALLOWED_ERROR", message=_("Must be POST request."), error_code=405)

    json_workflow = format_dict_field_values(json.loads(request.POST.get("workflow")))
    json_workflow.setdefault("schema_version", workflow.schema_version)

    form = WorkflowForm(data=json_workflow)

    if not form.is_valid():
        raise StructuredException(
            code="INVALID_REQUEST_ERROR",
            message=_("Error saving workflow"),
            data={"errors": form.errors},
            error_code=400,
        )

    json_nodes = json_workflow["nodes"]
    id_map = {}
    errors = {}

    if not _validate_nodes_json(json_nodes, errors, request.user, workflow):
        raise StructuredException(
            code="INVALID_REQUEST_ERROR", message=_("Error saving workflow"), data={"errors": errors}, error_code=400
        )

    workflow = _update_workflow_json(json_workflow)
    nodes = _update_workflow_nodes_json(workflow, json_nodes, id_map, request.user)

    # Update links
    index = 0
    for json_node in json_nodes:
        child_links = json_node["child_links"]
        Link.objects.filter(parent=nodes[index]).delete()

        for child_link in child_links:
            link = Link()
            link.id = getattr(child_link, "id", None)
            link.name = child_link["name"]

            id = str(child_link["parent"])
            link.parent = Node.objects.get(id=id_map[id])

            id = str(child_link["child"])
            link.child = Node.objects.get(id=id_map[id])

            link.comment = child_link.get("comment", "")

            link.save()

        index += 1

    # Make sure workflow HDFS permissions are correct
    Workflow.objects.check_workspace(workflow, request.fs)

    return _workflow(request, workflow=workflow)

  def helper(workflow, node, last_fork):
    if isinstance(node, Fork):
      join = None
      children = node.get_children()
      for child in children:
        join = helper(workflow, child.get_full_node(), node) or join
      link = Link(name='related', parent=node, child=join)
      link.save()

      node = join

    elif isinstance(node, Join):
      return node

    join = None
    children = node.get_children()
    for child in children:
      join = helper(workflow, child.get_full_node(), last_fork) or join
    return join

def workflow_save(request, workflow):
  if request.method != 'POST':
    raise StructuredException(code="METHOD_NOT_ALLOWED_ERROR", message=_('Must be POST request.'), error_code=405)

  json_workflow = format_dict_field_values(json.loads(str(request.POST.get('workflow'))))
  json_workflow.setdefault('schema_version', workflow.schema_version)

  form = WorkflowForm(data=json_workflow)

  if not form.is_valid():
    raise StructuredException(code="INVALID_REQUEST_ERROR", message=_('Error saving workflow'), data={'errors': form.errors}, error_code=400)

  json_nodes = json_workflow['nodes']
  id_map = {}
  errors = {}

  if not _validate_nodes_json(json_nodes, errors, request.user, workflow):
    raise StructuredException(code="INVALID_REQUEST_ERROR", message=_('Error saving workflow'), data={'errors': errors}, error_code=400)

  workflow = _update_workflow_json(json_workflow)
  nodes = _update_workflow_nodes_json(workflow, json_nodes, id_map, request.user)

  # Update links
  index = 0
  for json_node in json_nodes:
    child_links = json_node['child_links']
    Link.objects.filter(parent=nodes[index]).delete()

    for child_link in child_links:
      link = Link()
      link.id = getattr(child_link, 'id', None)
      link.name = child_link['name']

      id = str(child_link['parent'])
      link.parent = Node.objects.get(id=id_map[id])

      id = str(child_link['child'])
      link.child = Node.objects.get(id=id_map[id])

      link.comment = child_link.get('comment', '')

      link.save()

    index += 1

  # Make sure workflow HDFS permissions are correct
  Workflow.objects.check_workspace(workflow, request.fs)

  return _workflow(request, workflow=workflow)

    raise StructuredException(code="INVALID_REQUEST_ERROR", message=_('Error saving workflow'), data={'more': str(e)}, error_code=400)

  json_nodes = json_workflow['nodes']
  id_map = {}

  workflow = update_workflow(json_workflow)
  nodes = update_workflow_nodes(workflow, json_nodes, id_map)

  # Update links
  index = 0
  for json_node in json_nodes:
    child_links = json_node['child_links']
    Link.objects.filter(parent=nodes[index]).delete()

    for child_link in child_links:
      link = Link()
      link.id = getattr(child_link, 'id', None)
      link.name = child_link['name']

      id = str(child_link['parent'])
      link.parent = Node.objects.get(id=id_map[id])

      id = str(child_link['child'])
      link.child = Node.objects.get(id=id_map[id])

      link.comment = child_link.get('comment', '')

      link.save()

    index += 1