Task App - Task Overview Projection
Task Overview Projection
1
Select the Use Case Type Projection (P)
- After selecting an aggregate, click the Use Case Projection (P)
- Your cursor turns into the P icon
2
Place the Projection
- Click on the Plan to place the Projection
- The Projection Use Case will then appear on the Plan
Projection Use Case placed on the Plan
Use Case Sub Menu
1
Select the added Projection (P) Use Case
- Click the added Projection (P) Use Case.
Projection with open sub elements view
Add Source Events
1
Open the Use Case menu
- Click the Use Case menu icon on left side.
2
Add 'task added' Event
- Select the 'task added' source event and press the add button.
3
Add 'task completed' Event
- Select the 'task completed' source event and press the add button.
Projection 'task overview' with Events
Rename Projection
1
Change the Readmodel name
- Click the name input of the Readmodel.
- Type in 'task overview'.
- Confirm the new name by clicking on 'save'.
API Request with changed name
Schema
1
Add 'task id' property
- Click the plus icon on the right.
- Type 'task id' in the name input.
- Select 'uuid' in the type dropdown.
- Check the 'primary key' checkbox.
- Click the ✓ to save the property.
2
Add 'task added' Event properties
- Click the 'copy to readmodel' button on the 'task added' Event.
- The properties 'title', 'description' and 'assignee id' will appear in the Readmodel schema.
- All 3 properties already have the corresponding Values Source.
3
Add 'task status' property
- Click the plus icon on the right.
- Type 'task status' in the name input.
- Select 'enum' in the type dropdown.
- Select 'task status' in the enum dropdown.
- Click the ✓ to save the property.
Readmodel with new properties
Project Task Added
Projection Operation
1
Set the Projection operation
- Keep the option 'upsert one' as Projection Operation.
Projection with Projection Operation 'upsert one'
Condition
1
Add Projection condition for the 'task added' Event
- Click the plus button next to 'conditions' of the Readmodel on the right of the 'task added' Event
2
Select the Value Target
- Select the property 'task id'.
The Value Target is a property of the Readmodel schema.
The Value Target provides the property name of the projection WHERE condition.
3
Value Source type
- Select the Value Source type 'Metadata'.
4
Select the Value Source
- Select 'task added.aggregate id'.
- Click the ✓ to save the Condition.
The Value Source provides the property value of the projection WHERE condition.
Projection with condition
Value Sources
1
Set the Value Source for the 'task id' property
- Click the plus button on the right of the 'task id' property.
2
Value Source type
- Select the Value Source type 'Metadata'.
3
Select the Value Source
- Select 'task added.aggregate id'.
- Click the ✓ to save the Value Source.
4
Set the Value Source for the 'task status' property
- Click the plus button on the right of the 'task status' property.
5
Set the Value Source type for the 'task status' property
- Select the Value Source type 'Static'.
6
Set 'open' as Static Value Source for the 'task status' property
- Select the Value Source value 'open'.
- Click the ✓ button on the right.
Projection for 'task added' Event
Project Task Completed
Projection Operation
1
Set the Projection operation
- Set the option 'update one' as Projection Operation.
Projection with Projection Operation 'update one'
Condition
1
Add Projection condition for the 'task completed' Event
- Click the plus button next to 'conditions' of the Readmodel on the right of the 'task completed' Event
2
Select the Value Target
- Select the property 'task id'.
The Value Target is a property of the Readmodel schema.
The Value Target provides the property name the projection WHERE condition.
3
Value Source type
- Select the Value Source type 'Metadata'.
4
Select the Value Source
- Select 'task completed.aggregate id'.
- Click the ✓ to save the Condition.
The Value Source provides the property value of the projection WHERE condition.
Projection with condition
Value Sources
1
Set the Value Source for the 'task id' property
- Click the plus button on the right of the 'task id' property.
2
Value Source type
- Select the Value Source type 'Metadata'.
3
Select the Value Source
- Select 'task completed.aggregate id'.
- Click the ✓ to save the Value Source.
4
Set the Value Source for the 'task status' property
- Click the plus button on the right of the 'task status' property.
5
Set the Value Source type for the 'task status' property
- Select the Value Source type 'Static'.
6
Set 'completed' as Static Value Source for the 'task status' property
- Select the Value Source value 'completed'.
- Click the ✓ button on the right.
Projection for 'task completed' Event
Set Overview Projection Ready
1
Select task overview projection Use Case
- Click the task overview projection Use Case.
2
Open the Use Case menu
- Click the Use Case menu icon on left side.
3
Set generation status to ready
- Set the generation status from 'planned' to 'ready'.
Planned Use Cases have a blue border, the Code Generator wont generate its code.
Ready Use Cases have a gray border, the Code Generator generates its code.
The three Use Cases are ready for Code Generation
Generate the Code
1
Open the Code Generator menu
- Click on the 'Code' button to open the Code Generator menu.
2
Start Code Generation
- Click the 'Generate Code' button.
3
Generating code
- Wait until the activity indicator disappears and 'Code Generation done' is displayed under the button.
- Open the selected Path with an IDE or Text Editor.
The generated code
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