Simple DSL for composing decision workflows for AWS Simple Workflow
Usher enables simple, dependency based compositions of activities and decisions for AWS Simple Workflows.
In the name of simplicity, this library has strong opinions on convention, with the ability to configure and override some of these conventions.
npm install usher --save
This is a simple example of 4 activities being defined to perform some tasks and returning their results. By themselves, these activities will do nothing until executed by a workflow. (To see how these activities are run, see the workflow example below.)
var usher = require'usher';var activities = usheractivities'linear-activities' 'my-domain-name'activity'activity1' '1.0.0'tasksuccess "key1": "value 1" ;activity'activity2' '1.0.0'tasksuccess "key2": "value 2" ;activity'activity3' '1.0.0'tasksuccess "key3": "value 3" ;activity'activity4' '1.0.0'tasksuccess "key4": "old value 4" ;activity'activity4' '1.1.0'tasksuccess "key4": "value 4" ;;activitiesstart;
This is a simple example of the workflow composition that will run the previously defined 4 activities in sequential order when the workflow is executed.
var usher = require'usher';var workflow = usherworkflow'linear-workflow' 'my-domain-name'version'1.0.0'activity'activity1'activity'activity2' 'activity1'activity'activity3' 'activity2'activity'activity4' 'activity3' version: '1.1.0' ;workflowstart;
Given the above defined
linear-workflow, you could run an execution of the workflow in the following way.
var usher = require'usher';// This assumes the workflow 'linerar-workflow' has already been defined previouslyvar workflow = usherworkflow'linear-workflow' 'my-domain-name';workflowexecute key: 'value '// once the workflow has started;
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