viewflow-rest

provide restful viewflow

many of code in the project looks like django-viewflow. I want to keep the interface as same as the django viewflow.

Thanks you for all the contributors of viewflow.

The project is under ONLY USE NO PRIVATE CHANGE LICENSE, any one who change the source code (even if you just use it in intranet of just at home) should publish his code to public

Example

the flow graph can been cloned the changed from this link.

exam flow

this graph like above picture can be written like the below code:

# example_project/exam/flows.py
class ExamFlow(flows.Flow):

    process_class = models.ExamProcess
    task_class = models.ExamTask

    register = nodes.Start(
        viewclass=rest_extensions.AutoCreateAPIView,
        serializer_class=serializers.RegisterExamSerializer,
    ).Next(
        this.select_term
    )

    select_term = nodes.View(
        viewclass=rest_extensions.AutoUpdateAPIView,
        fields=["term"],
    ).Next(this.take_exam)

    take_exam = nodes.View(
        viewclass=rest_extensions.AutoUpdateAPIView,
        fields=["grade"],
    ).Next(this.check_grade)

    check_grade = nodes.If(
        cond=lambda activation: activation.process.passed
    ).Then(this.end).Else(this.select_term)
    end = nodes.End()

quite simple and intuitive, right?

hire flow

source code

class HireFlow(flows.Flow):

    process_class = models.HireProcess
    task_class = models.HireTask

    start = nodes.Start(
        viewclass=rest_extensions.AutoCreateAPIView,
        serializer_class=serializers.AddCandidateSerializer,
    ).Permission(
        group=Group.objects.get_or_create(name="hr")[0]
    ).Next(
        this.split_to_3rd_and_direct_leader
    )

    split_to_3rd_and_direct_leader = nodes.Split(
    ).Always(
        this.approve
    ).Always(
        this.background_research
    )

    background_research = nodes.View(
        viewclass=rest_extensions.AutoUpdateAPIView,
        fields=["background_ok"],
    ).Next(
        this.check_background
    )

    check_background = nodes.If(
        cond=lambda activation: activation.process.background_ok
    ).Then(
        this.join_on_both_approve
    ).Else(
        this.end
            )

    join_on_both_approve = nodes.Join().Next(
        this.notify
    )

    notify = nodes.View(
        viewclass=rest_extensions.AutoUpdateAPIView,
        fields=["notified"],
    ).Next(
        this.end
    )

    approve = nodes.View(
        viewclass=rest_extensions.AutoUpdateAPIView,
        serializer_class = serializers.ApproveSerializer,
        # fields=["approved"],
    ).Permission(
        group=Group.objects.get_or_create(name="leader")[0]
    ).Next(
        this.check_if_approve
    )

    check_if_approve = nodes.If(
        cond=lambda activation: activation.process.approved
    ).Then(
        this.set_salary
    ).Else(
        this.notify
    )

    set_salary = nodes.View(
        viewclass=rest_extensions.AutoUpdateAPIView,
        fields=["salary"],
    ).Permission(
        group=Group.objects.get_or_create(name="hr")[0]
    ).Next(
        this.join_on_both_approve
    )

    end = nodes.End()

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Quick Start

use the example_project as a example

git clone git@github.com:ramwin/viewflow-rest.git
cd vieflow-rest/example_project/
sudo pip3 install -r ./requirements.txt
python3 manage.py migrate
python3 manage.py runserver
# visit http://localhost:8000/exam/ or http://localhost:8000/hire/ to get the api

Change Log

3.0.0 warning: break change abount the signals

The post_finish and post_start signal not use the flow_task instead of a flow_process as a sender. You should change your code from

task_started.connect(function, ProcessClass)

to

task_started.connect(function, ProcessClass.one_of_its_flow_task)

FAQ

• How To Update the Task manually

task = models.FlowTaskModel.objects.get(id=4)
task.auto_finish(operator=User) or operator=None

The develop vedio can been seen here

1. create project
2. create Flow
3. Create Start & End Node
4. Create ViewActivation
5. Create If Node
6. Create Split Node
7. Create Join Node
8. Create Permission
9. 0.3.0
   • one task for every flow_task
   • add serializer_class parameters for rest_extentions.views
   • add operator for every task

Contribution Guildline

1. fork and clone this repository.

git clone git@github.com:<your_username>/viewflow-rest.git

2. make your change in your own repository.
3. make sure you pass the unittest

cd example_project
python manage.py test

4. create a pull request.

term

workflow

A flow contains many flow_tasks/nodes

# here exam_flow is a workflow
# it contains three flow_tasks, which were register, do, end
class ExamFlow(flows.Flow):
    register = nodes.Start(
        ...
    ).Next(this.do)
    do.nodes.View(
        ...
    ).Next(this.end)
    end = nodes.End()
exam_flow = ExamFlow()

every flow_task is a instance of Node every flow_task have a activation_class
every action_class instance will activate_next by

self.flow_task._next  // the next node instance
self.flow_task._next.activate // 

flow_task

Edge

• src: source Node instance
• dst: target Node instance

activations

• Attribute
  • flow_class
  • flow_task: Node Instance defined in the flows.py
  • task: Current Task

Nodes

• Function
  • _incoming: Edge Instance list
  • _outgoing: Edge Instance list

3. models

4. Views

5. Flow

6. rest_extensions