release notes

Author: danielgerlag

ReleaseNotes/3.0.0.md

@@ -0,0 +1,61 @@
+# Workflow Core 3.0.0
+
+### Split DSL into own package
+
+The JSON and YAML definition features into their own package.
+
+Migration required for existing projects:
+
+* Install the `WorkflowCore.DSL` package from nuget.
+* Call `AddWorkflowDSL()` on your service collection.
+
+### Activities
+
+An activity is defined as an item on an external queue of work, that a workflow can wait for.
+
+In this example the workflow will wait for `activity-1`, before proceeding.  It also passes the value of `data.Value1` to the activity, it then maps the result of the activity to `data.Value2`.
+
+Then we create a worker to process the queue of activity items.  It uses the `GetPendingActivity` method to get an activity and the data that a workflow is waiting for.
+
+
+
+```C#
+public class ActivityWorkflow : IWorkflow<MyData>
+{
+    public void Build(IWorkflowBuilder<MyData> builder)
+    {
+        builder                
+            .StartWith<HelloWorld>()
+            .Activity("activity-1", (data) => data.Value1)
+                .Output(data => data.Value2, step => step.Result)
+            .Then<PrintMessage>()
+                .Input(step => step.Message, data => data.Value2);
+    }
+             
+}
+...
+
+var activity = host.GetPendingActivity("activity-1", "worker1", TimeSpan.FromMinutes(1)).Result;
+
+if (activity != null)
+{
+    Console.WriteLine(activity.Parameters);
+    host.SubmitActivitySuccess(activity.Token, "Some response data");
+}
+
+```
+
+The JSON representation of this step would look like this
+
+```json
+{
+    "Id": "activity-step",
+    "StepType": "WorkflowCore.Primitives.Activity, WorkflowCore",
+    "Inputs": 
+    {
+        "ActivityName": "\"activity-1\"",
+        "Parameters": "data.Value1" 
+    },
+    "Outputs": { "Value2": "step.Result" }
+}
+```