mirror of https://github.com/dapr/quickstarts.git
66 lines
1.7 KiB
Markdown
66 lines
1.7 KiB
Markdown
# Fan-out/Fan-in
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This tutorial demonstrates how to author a workflow where multiple independent tasks can be scheduled and executed simultaneously. The workflow can either wait until all tasks are completed, or when the fastest task is completed. For more information about the fan-out/fan-in pattern see the [Dapr docs](https://docs.dapr.io/developing-applications/building-blocks/workflow/workflow-patterns/#fan-outfan-in).
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## Inspect the code
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Open the `FanOutFanInWorkflow.cs` file in the `tutorials/workflow/csharp/fan-out-fan-in/FanOutFanIn` folder. This file contains the definition for the workflow.
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```mermaid
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graph LR
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SW((Start
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Workflow))
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subgraph for each word in the input
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GWL[GetWordLength]
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end
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SHORT[Select the
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shortest word]
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ALL[Wait until all tasks
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are completed]
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EW((End
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Workflow))
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SW --> GWL
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GWL --> ALL
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ALL --> SHORT
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SHORT --> EW
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```
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## Run the tutorial
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1. Use a terminal to navigate to the `tutorials/workflow/csharp/fan-out-fan-in` folder.
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2. Build the project using the .NET CLI.
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```bash
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dotnet build ./FanOutFanIn/
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```
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3. Use the Dapr CLI to run the Dapr Multi-App run file
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```bash
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dapr run -f .
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```
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4. Use the POST request in the [`fanoutfanin.http`](./fanoutfanin.http) file to start the workflow.
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The input for the workflow is an array of strings:
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```json
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[
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"which",
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"word",
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"is",
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"the",
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"shortest"
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]
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```
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5. Use the GET request in the [`fanoutfanin.http`](./fanoutfanin.http) file to get the status of the workflow.
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The expected serialized output of the workflow is:
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```txt
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"\"is\""
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```
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6. Stop the Dapr Multi-App run process by pressing `Ctrl+C`.
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