Beispiel #1
0
    def pop_jobs(self):
        """Get a set of nodes with satisfied dependencies"""
        res = []
        logging.info("Pop jobs")

        for running_node_dict in node_collection_manager.get_db_nodes_by_ids(
                self.monitoring_node_ids):
            # check status
            if NodeRunningStatus.is_finished(
                    running_node_dict['node_running_status']):
                node = Node.from_dict(running_node_dict)
                self.update_node(node)
                self.monitoring_node_ids.remove(node._id)

        if NodeRunningStatus.is_failed(self.node.node_running_status):
            logging.info("Job in DAG failed, pop_jobs returns []")
            return res

        cached_nodes = []
        for node_id in self.dependency_index_to_node_ids[0]:
            """Get the node and init its inputs, i.e. filling its resource_ids"""
            orig_node = self.node_id_to_node[node_id]
            for node_input in orig_node.inputs:
                for input_reference in node_input.input_references:
                    node_input.values.extend(self.node_id_to_node[to_object_id(
                        input_reference.node_id)].get_output_by_name(
                            input_reference.output_id).values)
            orig_node.node_running_status = NodeRunningStatus.IN_QUEUE
            node = orig_node.copy()

            if DAG._cacheable(node) and False:  # !!! _cacheable is broken
                try:
                    cache = self.node_cache_manager.get(
                        node, self.graph.author)
                    if cache:
                        node.node_running_status = NodeRunningStatus.RESTORED
                        node.outputs = cache.outputs
                        node.logs = cache.logs
                        node.cache_url = '{}/graphs/{}?nid={}'.format(
                            self.WEB_CONFIG.endpoint.rstrip('/'),
                            str(cache.graph_id),
                            str(cache.node_id),
                        )
                        cached_nodes.append(node)
                        continue
                except Exception as err:
                    logging.exception(
                        "Unable to update cache: `{}`".format(err))
            res.append(node)
        del self.dependency_index_to_node_ids[0]

        for node in cached_nodes:
            self.update_node(node)

        return res
Beispiel #2
0
    def __init__(self, filename):
        super(StaticListHub, self).__init__()

        self.list_of_nodes = []

        with open(filename) as f:
            data_list = json.load(f)
            for raw_node in data_list:
                # check if the node is valid
                node = Node.from_dict(raw_node)
                self.list_of_nodes.append(node.to_dict())
Beispiel #3
0
def _enhance_list_item(raw_item):
    if raw_item['_type'] == 'Group':
        # TODO proper checking
        items = []
        for raw_subitem in raw_item['items']:
            items.append(_enhance_list_item(raw_subitem))
        raw_item['items'] = items
        return raw_item
    # check if the node is valid
    node = Node.from_dict(raw_item)
    return node.to_dict()
Beispiel #4
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def test_serialization():
    node1 = get_test_node()
    node1_dict = node1.to_dict()
    node2 = Node.from_dict(node1_dict)
    node2_dict = node2.to_dict()

    print(node1_dict)
    print("-")
    print(node2_dict)

    assert compare_dictionaries(node1_dict,
                                node2_dict), "Serialized nodes are not equal"
Beispiel #5
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 def get_default_node(cls, is_workflow):
     node = Node()
     if cls.IS_GRAPH:
         nodes_parameter = Parameter.from_dict({
             'name': '_nodes',
             'parameter_type': ParameterTypes.LIST_NODE,
             'value': [],
             'mutable_type': False,
             'publicable': False,
             'removable': False,
             }
         )
         if not is_workflow:
             # need to add inputs and outputs
             import logging
             logging.info(type(nodes_parameter.value.value), 'a')
             nodes_parameter.value.value.extend(
                 [
                     Node.from_dict({
                         '_id': SpecialNodeId.INPUT,
                         'title': 'Input',
                         'description': 'Operation inputs',
                         'node_running_status': NodeRunningStatus.SPECIAL,
                         'node_status': NodeStatus.READY,
                     }),
                     Node.from_dict({
                         '_id': SpecialNodeId.OUTPUT,
                         'title': 'Output',
                         'description': 'Operation outputs',
                         'node_running_status': NodeRunningStatus.SPECIAL,
                         'node_status': NodeStatus.READY,
                     }),
                 ]
             )
         node.parameters.extend([
             nodes_parameter,
         ])
         node.arrange_auto_layout()
     return node
Beispiel #6
0
    def upgrade_nodes(graph):
        """Upgrade deprecated Nodes.

        The function does not change the Graph in the database.

        Return:
            (int)   Number of upgraded Nodes
        """
        node_ids = set(
            [to_object_id(node.parent_node) for node in graph.nodes])
        db_nodes = GraphCollectionManager.node_collection_manager.get_db_nodes_by_ids(
            node_ids)
        new_node_db_mapping = {}

        for db_node in db_nodes:
            original_parent_node_id = db_node['_id']
            new_db_node = db_node
            if original_parent_node_id not in new_node_db_mapping:
                while new_db_node[
                        'node_status'] != NodeStatus.READY and 'successor_node' in new_db_node and new_db_node[
                            'successor_node']:
                    n = GraphCollectionManager.node_collection_manager.get_db_node(
                        new_db_node['successor_node'])
                    if n:
                        new_db_node = n
                    else:
                        break
                new_node_db_mapping[original_parent_node_id] = new_db_node

        new_nodes = [
            GraphCollectionManager._transplant_node(
                node,
                Node.from_dict(new_node_db_mapping[to_object_id(
                    node.parent_node)])) for node in graph.nodes
        ]

        upgraded_nodes_count = sum(
            1 for node, new_node in zip(graph.nodes, new_nodes)
            if node.parent_node != new_node.parent_node)

        graph.nodes = new_nodes
        return upgraded_nodes_count
Beispiel #7
0
    def upgrade_sub_nodes(self, main_node):
        """Upgrade deprecated Nodes.

        The function does not change the original graph in the database.

        Return:
            (int):  Number of upgraded Nodes
        """
        assert self.collection == Collections.TEMPLATES
        sub_nodes = main_node.get_parameter_by_name('_nodes').value.value
        node_ids = set([node.original_node_id for node in sub_nodes])
        db_nodes = self.get_db_objects_by_ids(node_ids)
        new_node_db_mapping = {}

        for db_node in db_nodes:
            original_node_id = db_node['_id']
            new_db_node = db_node
            if original_node_id not in new_node_db_mapping:
                while new_db_node[
                        'node_status'] != NodeStatus.READY and 'successor_node_id' in new_db_node and new_db_node[
                            'successor_node_id']:
                    n = self.get_db_node(new_db_node['successor_node_id'])
                    if n:
                        new_db_node = n
                    else:
                        break
                new_node_db_mapping[original_node_id] = new_db_node

        new_nodes = [
            NodeCollectionManager._transplant_node(
                node,
                Node.from_dict(new_node_db_mapping[to_object_id(
                    node.original_node_id)])) for node in sub_nodes
        ]

        upgraded_nodes_count = sum(
            1 for node, new_node in zip(sub_nodes, new_nodes)
            if node.original_node_id != new_node.original_node_id)

        main_node.get_parameter_by_name('_nodes').value.value = new_nodes
        return upgraded_nodes_count
Beispiel #8
0
def post_node(collection):
    app.logger.debug(request.data)

    data = json.loads(request.data)

    node = Node.from_dict(data['node'])
    node.starred = False
    action = data['action']
    db_node = node_collection_managers[collection].get_db_node(
        node._id, g.user._id)

    if db_node:
        if not node.author:
            node.author = db_node['author']
        if node.author != db_node['author']:
            raise Exception(
                "Author of the node does not match the one in the database")
        is_author = db_node['author'] == g.user._id
    else:
        # assign the author
        node.author = g.user._id
        is_author = True

    is_admin = g.user.check_role(IAMPolicies.IS_ADMIN)
    is_workflow = node.kind in workflow_manager.kind_to_workflow_dict

    can_create_operations = g.user.check_role(
        IAMPolicies.CAN_CREATE_OPERATIONS)
    can_create_workflows = g.user.check_role(IAMPolicies.CAN_CREATE_WORKFLOWS)
    can_modify_others_workflows = g.user.check_role(
        IAMPolicies.CAN_MODIFY_OTHERS_WORKFLOWS)
    can_run_workflows = g.user.check_role(IAMPolicies.CAN_RUN_WORKFLOWS)

    if action == NodePostAction.SAVE:
        if (is_workflow and not can_create_workflows) or (
                not is_workflow and not can_create_operations):
            return make_permission_denied(
                'You do not have permission to save this object')

        if node.node_status != NodeStatus.CREATED:
            return make_fail_response(
                'Cannot save node with status `{}`'.format(node.node_status))

        if is_author or is_admin or (is_workflow
                                     and can_modify_others_workflows):
            node.save(force=True)
        else:
            return make_permission_denied(
                'Only the owners or users with CAN_MODIFY_OTHERS_WORKFLOWS role can save it'
            )

    elif action == NodePostAction.APPROVE:
        if is_workflow:
            return make_fail_response('Invalid action for a workflow'), 400
        if node.node_status != NodeStatus.CREATED:
            return make_fail_response(
                'Node status `{}` expected. Found `{}`'.format(
                    NodeStatus.CREATED, node.node_status))
        validation_error = executor_manager.kind_to_executor_class[node.kind](
            node).validate()
        if validation_error:
            return make_success_response({
                'status':
                NodePostStatus.VALIDATION_FAILED,
                'message':
                'Node validation failed',
                'validation_error':
                validation_error.to_dict()
            })

        node.node_status = NodeStatus.READY

        if is_author or is_admin:
            node.save(force=True)
        else:
            return make_permission_denied()

    elif action == NodePostAction.CREATE_RUN:
        if not is_workflow:
            return make_fail_response('Invalid action for an operation'), 400
        if node.node_status != NodeStatus.CREATED:
            return make_fail_response(
                'Node status `{}` expected. Found `{}`'.format(
                    NodeStatus.CREATED, node.node_status))
        validation_error = executor_manager.kind_to_executor_class[node.kind](
            node).validate()
        if validation_error:
            return make_success_response({
                'status':
                NodePostStatus.VALIDATION_FAILED,
                'message':
                'Node validation failed',
                'validation_error':
                validation_error.to_dict()
            })

        node = node.clone(NodeClonePolicy.NODE_TO_RUN)
        node.author = g.user._id
        if is_admin or can_run_workflows:
            node.save(collection=Collections.RUNS)
        else:
            return make_permission_denied(
                'You do not have CAN_RUN_WORKFLOWS role')

        return make_success_response({
            'status':
            NodePostStatus.SUCCESS,
            'message':
            'Run(_id=`{}`) successfully created'.format(str(node._id)),
            'run_id':
            str(node._id),
            'url':
            '/{}/{}'.format(Collections.RUNS, node._id),
        })

    elif action == NodePostAction.CLONE:
        if (is_workflow and not can_create_workflows) or (
                not is_workflow and not can_create_operations):
            return make_permission_denied(
                'You do not have the role to create an object')
        node_clone_policy = None
        if collection == Collections.TEMPLATES:
            node_clone_policy = NodeClonePolicy.NODE_TO_NODE
        elif collection == Collections.RUNS:
            node_clone_policy = NodeClonePolicy.RUN_TO_NODE

        node = node.clone(node_clone_policy)
        node.save(collection=Collections.TEMPLATES)

        return make_success_response({
            'message':
            'Node(_id=`{}`) successfully created'.format(str(node._id)),
            'node_id':
            str(node._id),
            'url':
            '/{}/{}'.format(Collections.TEMPLATES, node._id),
        })

    elif action == NodePostAction.VALIDATE:
        validation_error = executor_manager.kind_to_executor_class[node.kind](
            node).validate()

        if validation_error:
            return make_success_response({
                'status':
                NodePostStatus.VALIDATION_FAILED,
                'message':
                'Node validation failed',
                'validation_error':
                validation_error.to_dict()
            })
    elif action == NodePostAction.DEPRECATE:
        if node.node_status == NodeStatus.CREATED:
            return make_fail_response('Node status `{}` not expected.'.format(
                node.node_status))

        node.node_status = NodeStatus.DEPRECATED

        if is_author or is_admin:
            node.save(force=True)
        else:
            return make_permission_denied(
                'You are not an author to deprecate it')

    elif action == NodePostAction.MANDATORY_DEPRECATE:
        if node.node_status == NodeStatus.CREATED:
            return make_fail_response('Node status `{}` not expected.'.format(
                node.node_status))

        node.node_status = NodeStatus.MANDATORY_DEPRECATED

        if is_author or is_admin:
            node.save(force=True)
        else:
            return make_permission_denied(
                'You are not an author to deprecate it')

    elif action == NodePostAction.PREVIEW_CMD:

        return make_success_response({
            'message':
            'Successfully created preview',
            'preview_text':
            executor_manager.kind_to_executor_class[node.kind](node).run(
                preview=True)
        })

    elif action == NodePostAction.REARRANGE_NODES:
        node.arrange_auto_layout()
        return make_success_response({
            'message': 'Successfully created preview',
            'node': node.to_dict(),
        })
    elif action == NodePostAction.UPGRADE_NODES:
        upd = node_collection_managers[collection].upgrade_sub_nodes(node)
        return make_success_response({
            'message': 'Successfully updated nodes',
            'node': node.to_dict(),
            'upgraded_nodes_count': upd,
        })
    elif action == NodePostAction.CANCEL:

        if is_author or is_admin:
            run_cancellation_manager.cancel_run(node._id)
        else:
            return make_permission_denied(
                'You are not an author to cancel the run')

    elif action == NodePostAction.GENERATE_CODE:
        raise NotImplementedError()
    else:
        return make_fail_response('Unknown action `{}`'.format(action))

    return make_success_response({
        'message':
        'Node(_id=`{}`) successfully updated'.format(str(node._id))
    })
Beispiel #9
0
def post_node(collection):
    app.logger.debug(request.data)

    data = json.loads(request.data)

    node = Node.from_dict(data['node'])
    node.author = g.user._id
    node.starred = False
    db_node = node_collection_managers[collection].get_db_node(
        node._id, g.user._id)
    action = data['action']
    if db_node and db_node[
            '_readonly'] and action not in PERMITTED_READONLY_POST_ACTIONS:
        return make_fail_response('Permission denied'), 403

    if action == NodePostAction.SAVE:
        if node.node_status != NodeStatus.CREATED and node.base_node_name != 'file':
            return make_fail_response(
                'Cannot save node with status `{}`'.format(node.node_status))

        node.save(force=True)

    elif action == NodePostAction.APPROVE:
        if node.node_status != NodeStatus.CREATED:
            return make_fail_response(
                'Node status `{}` expected. Found `{}`'.format(
                    NodeStatus.CREATED, node.node_status))
        validation_error = executor_manager.kind_to_executor_class[node.kind](
            node).validate()
        if validation_error:
            return JSONEncoder().encode({
                'status':
                NodePostStatus.VALIDATION_FAILED,
                'message':
                'Node validation failed',
                'validation_error':
                validation_error.to_dict()
            })

        node.node_status = NodeStatus.READY
        node.save(force=True)

    elif action == NodePostAction.CREATE_RUN:
        if node.node_status != NodeStatus.CREATED:
            return make_fail_response(
                'Node status `{}` expected. Found `{}`'.format(
                    NodeStatus.CREATED, node.node_status))
        validation_error = executor_manager.kind_to_executor_class[node.kind](
            node).validate()
        if validation_error:
            return JSONEncoder().encode({
                'status':
                NodePostStatus.VALIDATION_FAILED,
                'message':
                'Node validation failed',
                'validation_error':
                validation_error.to_dict()
            })

        node = node.clone(NodeClonePolicy.NODE_TO_RUN)
        node.save(collection=Collections.RUNS)
        return JSONEncoder().encode({
            'status':
            NodePostStatus.SUCCESS,
            'message':
            'Run(_id=`{}`) successfully created'.format(str(node._id)),
            'run_id':
            str(node._id),
            'url':
            '/{}/{}'.format(Collections.RUNS, node._id),
        })

    elif action == NodePostAction.CLONE:
        node_clone_policy = None
        if collection == Collections.TEMPLATES:
            node_clone_policy = NodeClonePolicy.NODE_TO_NODE
        elif collection == Collections.RUNS:
            node_clone_policy = NodeClonePolicy.RUN_TO_NODE

        node = node.clone(node_clone_policy)
        node.save(collection=Collections.TEMPLATES)

        return JSONEncoder().encode({
            'status':
            NodePostStatus.SUCCESS,
            'message':
            'Node(_id=`{}`) successfully created'.format(str(node._id)),
            'node_id':
            str(node._id),
            'url':
            '/{}/{}'.format(Collections.TEMPLATES, node._id),
        })

    elif action == NodePostAction.VALIDATE:
        validation_error = executor_manager.kind_to_executor_class[node.kind](
            node).validate()

        if validation_error:
            return JSONEncoder().encode({
                'status':
                NodePostStatus.VALIDATION_FAILED,
                'message':
                'Node validation failed',
                'validation_error':
                validation_error.to_dict()
            })
    elif action == NodePostAction.DEPRECATE:
        if node.node_status == NodeStatus.CREATED:
            return make_fail_response('Node status `{}` not expected.'.format(
                node.node_status))

        node.node_status = NodeStatus.DEPRECATED
        node.save(force=True)
    elif action == NodePostAction.MANDATORY_DEPRECATE:
        if node.node_status == NodeStatus.CREATED:
            return make_fail_response('Node status `{}` not expected.'.format(
                node.node_status))

        node.node_status = NodeStatus.MANDATORY_DEPRECATED
        node.save(force=True)
    elif action == NodePostAction.PREVIEW_CMD:

        return JSONEncoder().encode({
            'status':
            NodePostStatus.SUCCESS,
            'message':
            'Successfully created preview',
            'preview_text':
            executor_manager.kind_to_executor_class[node.kind](node).run(
                preview=True)
        })

    elif action == NodePostAction.REARRANGE_NODES:
        node.arrange_auto_layout()
        return JSONEncoder().encode(
            dict({
                'status': NodePostStatus.SUCCESS,
                'message': 'Successfully created preview',
                'node': node.to_dict(),
            }))
    elif action == NodePostAction.UPGRADE_NODES:
        upd = node_collection_managers[collection].upgrade_sub_nodes(node)
        return JSONEncoder().encode(
            dict({
                'status': NodePostStatus.SUCCESS,
                'message': 'Successfully updated nodes',
                'node': node.to_dict(),
                'upgraded_nodes_count': upd,
            }))
    elif action == NodePostAction.CANCEL:
        run_cancellation_manager.cancel_run(node._id)
    elif action == NodePostAction.GENERATE_CODE:
        raise NotImplementedError()
    else:
        return make_fail_response('Unknown action `{}`'.format(action))

    return JSONEncoder().encode({
        'status':
        NodePostStatus.SUCCESS,
        'message':
        'Node(_id=`{}`) successfully updated'.format(str(node._id))
    })
Beispiel #10
0
def post_node():
    app.logger.debug(request.data)

    data = json.loads(request.data)

    node = Node.from_dict(data['node'])
    node.author = g.user._id
    node.starred = False
    db_node = node_collection_manager.get_db_node(node._id, g.user._id)
    action = data['action']
    if db_node and db_node[
            '_readonly'] and action not in PERMITTED_READONLY_POST_ACTIONS:
        return make_fail_response('Permission denied'), 403

    if action == NodePostAction.SAVE:
        if node.node_status != NodeStatus.CREATED and node.base_node_name != 'file':
            return make_fail_response(
                'Cannot save node with status `{}`'.format(node.node_status))

        node.save(force=True)

    elif action == NodePostAction.APPROVE:
        if node.node_status != NodeStatus.CREATED:
            return make_fail_response(
                'Node status `{}` expected. Found `{}`'.format(
                    NodeStatus.CREATED, node.node_status))
        validation_error = node.get_validation_error()
        if validation_error:
            return JSONEncoder().encode({
                'status':
                NodePostStatus.VALIDATION_FAILED,
                'message':
                'Node validation failed',
                'validation_error':
                validation_error.to_dict()
            })

        node.node_status = NodeStatus.READY
        node.save(force=True)

    elif action == NodePostAction.VALIDATE:
        validation_error = node.get_validation_error()

        if validation_error:
            return JSONEncoder().encode({
                'status':
                NodePostStatus.VALIDATION_FAILED,
                'message':
                'Node validation failed',
                'validation_error':
                validation_error.to_dict()
            })
    elif action == NodePostAction.DEPRECATE:
        if node.node_status == NodeStatus.CREATED:
            return make_fail_response('Node status `{}` not expected.'.format(
                node.node_status))

        node.node_status = NodeStatus.DEPRECATED
        node.save(force=True)
    elif action == NodePostAction.MANDATORY_DEPRECATE:
        if node.node_status == NodeStatus.CREATED:
            return make_fail_response('Node status `{}` not expected.'.format(
                node.node_status))

        node.node_status = NodeStatus.MANDATORY_DEPRECATED
        node.save(force=True)
    elif action == NodePostAction.PREVIEW_CMD:
        job = node_collection.make_job(node)

        return JSONEncoder().encode({
            'status': NodePostStatus.SUCCESS,
            'message': 'Successfully created preview',
            'preview_text': job.run(preview=True)
        })

    else:
        return make_fail_response('Unknown action `{}`'.format(action))

    return JSONEncoder().encode({
        'status':
        NodePostStatus.SUCCESS,
        'message':
        'Node(_id=`{}`) successfully updated'.format(str(node._id))
    })
Beispiel #11
0
def post_graph_node_action(graph_id, action):
    graph_dict = graph_collection_manager.get_db_graph(graph_id, g.user._id)
    if not graph_dict:
        return make_fail_response('Graph was not found'), 404

    if graph_dict['_readonly']:
        return make_fail_response('Permission denied'), 403

    if not request.data:
        return make_fail_response('Empty body'), 400

    data = json.loads(request.data)
    graph = Graph.from_dict(graph_dict)

    if action == GraphNodePostAction.INSERT_NODE:
        node_id = data.get('node_id', None)
        x, y = int(data.get('x', 0)), int(data.get('y', 0))

        node_dict = node_collection_manager.get_db_node(node_id)
        if not node_dict:
            return make_fail_response('Node was not found'), 404
        node = Node.from_dict(node_dict)
        node.x, node.y = x, y
        node.parent_node = node._id
        node._id = ObjectId()
        graph.nodes.append(node)
        graph.save()

        return make_success_response(node=node.to_dict())
    elif action == GraphNodePostAction.REMOVE_NODE:
        node_id = ObjectId(data.get('node_id', None))
        node_index = -1
        for index, node in enumerate(graph.nodes):
            for input in node.inputs:
                input.values = [value for value in input.values if ObjectId(value.node_id) != node_id]
            if ObjectId(node._id) == node_id:
                node_index = index
        if node_index < 0:
            return make_fail_response('Node was not found'), 404
        del graph.nodes[node_index]
        graph.save()
        return make_success_response('Node removed')
    elif action == GraphNodePostAction.CHANGE_PARAMETER:
        node_id = data.get('node_id', None)
        parameter_name = data.get('parameter_name', None)
        parameter_value = data.get('parameter_value', None)
        if parameter_name is None:
            return make_fail_response('No parameter name'), 400
        if parameter_value is None:
            return make_fail_response('No parameter value'), 400

        node, = _find_nodes(graph, node_id)
        if not node:
            return make_fail_response('Node was not found'), 404

        for parameter in node.parameters:
            if parameter.name == parameter_name:
                parameter_dict = parameter.to_dict()
                parameter_dict['value'] = parameter_value

                parameter.value = Parameter(obj_dict=parameter_dict).value
        graph.save()
        return make_success_response('Parameter updated')
    elif action in (GraphNodePostAction.CREATE_LINK, GraphNodePostAction.REMOVE_LINK):
        for field in ['from', 'to']:
            for sub_field in ['node_id', 'resource']:
                if field not in data:
                    return make_fail_response('`{}` is missing'.format(field)), 400
                if sub_field not in data[field]:
                    return make_fail_response('`{}.{}` is missing'.format(field, sub_field)), 400
        from_node_id = data['from']['node_id']
        from_resource = data['from']['resource']
        to_node_id = data['to']['node_id']
        to_resource = data['to']['resource']

        from_node, to_node = _find_nodes(graph, from_node_id, to_node_id)
        if not from_node or not to_node:
            return make_fail_response('Node was not found'), 404

        from_output = None
        to_input = None
        for output in from_node.outputs:
            if output.name == from_resource:
                from_output = output
                break
        for input in to_node.inputs:
            if input.name == to_resource:
                to_input = input
                break
        if not from_output or not to_input:
            return make_fail_response('Input or output not found'), 404

        if action == GraphNodePostAction.CREATE_LINK:
            # TODO graph.validate() it
            if from_output.file_type not in to_input.file_types and 'file' not in to_input.file_types:
                return make_fail_response('Incompatible types'), 400
            # TODO graph.validate() it
            if to_input.max_count > 0 and len(to_input.values) >= to_input.max_count:
                return make_fail_response('Number of inputs reached the limit'), 400

            new_input_value = InputValue()
            new_input_value.node_id = from_node_id
            new_input_value.output_id = from_resource
            # TODO graph.validate() it
            for value in to_input.values:
                if value.node_id == from_node_id and value.output_id == from_resource:
                    return make_fail_response('Link already exists'), 400
            to_input.values.append(new_input_value)
        elif action == GraphNodePostAction.REMOVE_LINK:
            rm_index = -1
            # TODO graph.validate() it
            for index, value in enumerate(to_input.values):
                if value.node_id == from_node_id and value.output_id == from_resource:
                    rm_index = index
                    break
            if rm_index < 0:
                return make_fail_response('Link not found'), 404
            del to_input.values[rm_index]

        graph.save()
        return make_success_response('Completed')
    else:
        return make_fail_response('Unknown action `{}`'.format(action)), 400

    return 'ok'