# Using cURL and Azure REST API to access Azure Resource Manager  (non-interactive)

**Note**: This guide assumes Azure CLI 2.0 is installed and familiarity with Azure concepts.

## Register Client App and Obtain Service Principal (via CLI)

The `APP_ID_URI` needs to match what is expected in client request calls.

```bash
$ az ad sp create-for-rbac --name [APP_ID_URI] --password [PASSWORD]

## Example:
$ az ad sp create-for-rbac --name "testMyApp" --password "123456"
```

Optionally, you could use the portal via: [https://docs.microsoft.com/en-us/azure/azure-resource-manager/resource-group-create-service-principal-portal](https://docs.microsoft.com/en-us/azure/azure-resource-manager/resource-group-create-service-principal-portal)

A response will provide an **appId** for a **tenantId**. We'll need both of those moving forward.

## Request an App Access Token

Main Reference: [https://docs.microsoft.com/en-us/azure/active-directory/develop/active-directory-protocols-oauth-service-to-service#request-an-access-token](https://docs.microsoft.com/en-us/azure/active-directory/develop/active-directory-protocols-oauth-service-to-service#request-an-access-token)

To get the app token we'll need the following information:
  - `APP_ID`
  - `TENANT_ID`
  - `PASSWORD`
  - `RESOURCE`
    - URI encode of Azure Resource Management API: `https://management.azure.com/` (with the forward slash)
        - Use `https%3A%2F%2Fmanagement.azure.com%2F` as the `RESOURCE` (properly URI-encoded)
    - Note: Must be URI-encoded and must match the URL of the domain we will request information from.
    - Example: `https://management.azure.com/` would be 

```bash
$ curl -X POST \
       -d 'grant_type=client_credentials&client_id=[APP_ID]&client_secret=[PASSWORD]&resource=https%3A%2F%2Fmanagement.azure.com%2F' \
     https://login.microsoftonline.com/[TENANT_ID]/oauth2/token
```

The response object will contain an `ACCESS_TOKEN`, we will use this in the  Resource Call.

## Example Call: List all Web Apps within a Subscription

API Reference for WebApps: [https://docs.microsoft.com/en-us/rest/api/appservice/webapps#WebApps_List](https://docs.microsoft.com/en-us/rest/api/appservice/webapps#WebApps_List)

### API Notes:
- Required Headers:
    - `"Content-Type: application/json"`
    - `"Authorization: Bearer [ACCESS_TOKEN]"`
- Required in URI:
    - Must include the `api-version` query param with the `host` 
        - Usually in the form of: `YYYY-MM-DD`
        - Example: `2016-08-01`
    - Must include the `SUBSCRIPTION_ID` in the URI

```bash
curl -X GET \
     -H "Authorization: Bearer [ACCESS_TOKEN]" \
     -H "Content-Type: application/json" \
     https://management.azure.com/subscriptions/[SUBSCRIPTION_ID]/providers/Microsoft.Web/sites?api-version=[API_VERSION]
```

## Troubeshooting 

- If you receive an error like a `400` for a bad header, make sure when you copy/paste your Access Token that there are no space (sometimes this occurs depending on which terminal you are copy/pasting from/to)
- If you need additional information about a request, use verbose mode in `cURL` by passing the `-v` flag.