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# Demo Application

* [Previous](https://developer.avalara.com/communications/dev-guide_rest_v2/getting-started/environments-endpoints/)
* [Next](https://developer.avalara.com/communications/dev-guide_rest_v2/getting-started/best-practices/)

Use the C# [Communications REST v2 Demo Application](https://github.com/Avalara/Communications-Developer-Content/tree/master/afc_saaspro_tax/afc_rest_apis/AfcRestDemoApp) to see how to integrate with and call the [`CalcTaxes`](https://developer.avalara.com/communications/dev-guide_rest_v2/calculate-taxes/) and [Geo Batch](https://developer.avalara.com/communications/dev-guide_rest_v2/customizing-transactions/sample-transactions/geo-batch/) REST v2 APIs.

### Download the Demo Application

1. Navigate to the [Avalara/Communications-Developer-Content](https://github.com/Avalara/Communications-Developer-Content) repo on [GitHub](https://github.com/)
2. Clone the master branch of the Avalara/Communications-Developer-Content repository locally
3. To run the application:
   1. Navigate to .\afc_saaspro_tax\afc_rest_apis\AfcRestDemoApp in the local repository
   2. Launch **RestDemoApplication.exe**
4. To view the source code and build the application:
   1. Navigate to .\afc_saaspro_tax\afc_rest_apis\AfcRestDemoSource in the local repository
   2. Open **RestDemoApplication.sln** in Microsoft Visual Studio

### Run a Sample Transaction

1. Enter your REST v2 Username, Password, and Client ID
2. In **Profile ID**, enter:

* `client_profile_id` to use an existing client profile (if applicable)
* `0` to use the default profile

4. Modify the **Request** or simply use the transaction provided

* See [Customizing Transactions](https://developer.avalara.com/communications/dev-guide_rest_v2/customizing-transactions/) for sample transactions

6. Click **Process** to run the transaction

![](https://developer.avalara.com/public/images/comms/dev-guide_rest_v2/rest_demo_app_sample_request.png)

### Run a Performance Test

1. Navigate to the **Performance** tab
2. Set **Max Threads** and **Max Run Time**
3. Click **Start** to start a performance test

The results of the test are displayed within the **Performance** tab.

![](https://developer.avalara.com/public/images/comms/dev-guide_rest_v2/rest_demo_app_performance.png)

### Run Geo Batch

Use the Geo Batch tab to upload an address or latitude/longitude CSV file and see the results.

* **Upload Request File** - upload a CSV input file
* **Get File Status** - Get the input and output file links
  * **Download Input File** - Download the request file
  * **Download Output File** - Download the results file
* **Get File Logs** - See the status details of the request

For more information about Geo Batch, see [Geo Batch](https://developer.avalara.com/communications/dev-guide_rest_v2/customizing-transactions/sample-transactions/geo-batch/).

The results of the Geo Batch test are displayed within the **Geo Batch**tab.

![](https://developer.avalara.com/public/images/comms/dev-guide_rest_v2/rest_demo_app_geo_batch.png)

* [Previous](https://developer.avalara.com/communications/dev-guide_rest_v2/getting-started/environments-endpoints/)
* [Next](https://developer.avalara.com/communications/dev-guide_rest_v2/getting-started/best-practices/)

> **Note**
>
> Part of the **Communications REST v2 Developer Guide** integration guide. [Open the full "Demo Application" milestone on Avalara](https://developer.avalara.com/products/communications/integration-guides/dev-guide_rest_v2/getting-started/) to see every page in this section.