gawati-workflow
v1.0.7
Published
Finite State Machine Workflow library for Node JS
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Gawati Workflow
Workflow configurations are supported in both XML and JSON, they can be created in XML, and converted into JSON for application consumption. You can generate directed graphs of the Worfklow based on the instructions below (that requires the Workflow configuration to be in XML).
Gawati Workflow is a stateful workflow, and is intended to support moving a document through different states via state transitions. The Workflow allows defining who can do what in each state, and also who is allowed to transit between states. Transitions connect states, and allow building complex workflows using just a few states.
The typical process is to edit the workflow in XML and generate the production JSON out of that using the xml2jon
script which has been provided.
Test
npm install
followed by ;npm test
- Unit tests are found in
test/testWorkflow.js
, which provide an overview of how the API can be used.
Generating Documentation
- NOTE: this requires the workflow configuration to be in XML format
npm install
in the package folder- Download Saxon
- Install Graphviz
Convert the Workflow XML to graphviz dot format
java -jar <path to saxon9 he>/saxon9he.jar wf/act-legislation.xml xslt/wf2dotML.xsl > act-legislation.dotML
java -jar <path to saxon9 he>/saxon9he.jar ./act-legislation.dotML xslt/dotml2dot.xsl > act-legislation.dot
Convert the dot file to an image
dot ./act-legislation.dot -Tsvg -o ./act-legislation.svg
See an example SVG generated from the model workflow:
Converting the Workflow XML to JSON
Run:
node xml2json.js --name=wf/act-legislation.xml
{"workflow":{"doctype":"act", .... "from":"publish","to":"review"}]}}}
To serialize it to a file:
node xml2json.js --name=wf/act-legislation.xml --output=wf/act-legislation.json
Workflow structure
Each workflow is defined using a <workflow>
tag, the attributes doctype
and subtype
correspond to Akoma Ntoso document type and sub types for the document. A workflow definition
<workflow doctype="act" subtype="legislation">
....
</workflow>
Permissions
We describe available permissions in a <permissions>
element. To the workflow package, the permissions are just labels and the application using the workflow needs to implement the corresponding functionality - except for the transit
permission which is specific to the workflow, and states who is allowed to transit from one state of the workflow to another.
<permissions>
<permission name="view" title="View" icon="fa-eye"/>
<permission name="edit" title="Edit" icon="fa-pencil"/>
<permission name="delete" title="Delete" icon="fa-trash-o"/>
<permission name="list" title="List" icon="fa-flag"/>
<permission name="transit" title="Transit" icon="fa-flag"/>
</permissions>
In the context of gawati the permissions are intended to have the following meaning: * view - allows viewing a document * edit - allows editing a document * delete - allows deleting a document * list - allows seeing the document in a list (but not viewing it) * transit - allows transiting from the state to another.
States
States are defined in the <states>
element and are uniquely identified via a name
attribute.
In a workflow a state is always unique. level
and color
attributes are there for purely documentation related purposes and are non mandatory.
A state defines permissions applicable in that state. Each permission
has to correspond to a name of a permission defined in the <permissions>
block. A permission in a state is always associated with one or more roles stated in the roles
attribute.
1 <state name="editable" title="Editable" level="2" color="initial">
2 <permission name="view" roles="admin editor"/>
3 <permission name="list" roles="admin editor submitter" />
4 <permission name="delete" roles="admin editor"/>
5 <permission name="edit" roles="admin editor"/>
6 <permission name="transit" roles="admin editor"/>
7 </state>
Permissions defined in a state have a particular meaning:
* line 2 : <permission name="view" roles="admin editor"/>
- only users with an admin or editor role can view the document
* line 3 : <permission name="list" roles="admin editor submitter" />
- only users with an admin, editor or submitter role can see the document in a listing
* line 4: <permission name="delete" roles="admin editor"/>
- only admin, editor users can delete the document
* line 6: <permission name="transit" roles="admin editor"/>
- only admin, editor users can transit the document via a state transition
Transitions
Transitions allow the document to be moved from one state to another:
<transitions>
<transition name="make_editable" icon="fa-thumbs-up" title="Send for Editing"
from="draft" to="editable" />
<transition name="make_drafting" icon="fa-thumbs-up" title="Back to Drafting"
from="editable" to="draft" />
...
<transition name="make_retract" icon="fa-building" title="Retract"
from="publish" to="review" />
</transitions>
A transition has to have a unique name
, the icon
attribute is a font-awesome icon code which is used in the UI next to the transition title. The transition also has from
and to
attributes each of which points to a <state>
name defined earlier.
This transition moves the document from editable
=>available_for_review
states.
<transition name="send_for_review" icon="fa-check" title="Send for Review"
from="editable" to="available_for_review" />
The transit
permission on the editable
state (which is the from
state), permits admin
and editor
role users to move the document from editable
to available_for_review
.
<state name="editable" title="Editable" level="2" color="initial">
...
<permission name="transit" roles="admin editor"/>
</state>
Actions
Transitions support both pre and post transit actions. These are essentially JS functions which can be configured on the workflow via a custom module and triggered by the calling API doing the transition. See testModule.js
in the unit tests, for an example of how this can be used.