To establish a connection with the REST API data source, you can either click on the **+ Add new Data source** button located on the query panel or navigate to the **[Data Sources](/docs/data-sources/overview)** page through the ToolJet dashboard.
Whenever a request is made to the REST API, a **tj-x-forwarded-for** header is added to the request, the value of the header will be the IP address of the user who is logged in to the ToolJet application. This header can be used to identify the user who is making the request to the REST API.
The plugin will send a **JSON** formatted body by default. If you want to send a different type of body, you can enter the appropriate headers in the **Headers** section.
REST APIs can return data in a variety of formats, including **JSON** and **Base64**. JSON is a common format used for data exchange in REST APIs, while Base64 is often used for encoding binary data, such as images or video, within a JSON response.
When the response **content-type** is **image**, the response will be a **base64** string.
"title": "Mens Casual Premium Slim Fit T-Shirts ",
"price": 22.3,
"description": "Slim-fitting style, contrast raglan long sleeve, three-button henley placket, light weight & soft fabric for breathable and comfortable wearing. And Solid stitched shirts with round neck made for durability and a great fit for casual fashion wear and diehard baseball fans. The Henley style round neckline includes a three-button placket.",
"description": "great outerwear jackets for Spring/Autumn/Winter, suitable for many occasions, such as working, hiking, camping, mountain/rock climbing, cycling, traveling or other outdoors. Good gift choice for you or your family member. A warm hearted love to Father, husband or son in this thanksgiving or Christmas Day.",
"description": "The color could be slightly different between on the screen and in practice. / Please note that body builds vary by person, therefore, detailed size information should be reviewed below on the product description.",
ToolJet’s REST API data source supports OAuth 2.0 as the authentication type.
Before setting up the REST API data source in ToolJet, we need to configure the **Google Cloud Platform** to gather the API keys required for the authorization access.
### Setting up Google Cloud Platform
Google Cloud Platform provides access to more than 350 APIs and Services that can allow us to access data from our Google account and its services. Let's create an OAuth application that can be given permission to use our Google profile data such as Name and Profile picture.
1. Sign in to your [Google Cloud](https://cloud.google.com/) account, and from the console create a New Project.
2. Navigate to the **APIs and Services**, and then open the **OAuth consent screen** section from the left sidebar.
3. Enter the Application details and select the appropriate scopes for your application. We will select the profile and the email scopes.
4. Once you have created the OAuth consent screen, Create new credentials for the **OAuth client ID** from the **Credentials** section in the left sidebar.
5. Select the application type, enter the application name, and then add the following URIs under Authorized Redirect URIs:
1.`https://app.tooljet.com/oauth2/authorize` (if you’re using ToolJet cloud)
2.`http://localhost:8082/oauth2/authorize` (if you’re using ToolJet locally)
6. Now save and then you’ll get the **Client ID and Client secret** for your application.
<imgclass="screenshot-full"src="/img/how-to/oauth2-authorization/gcp.png"alt="ToolJet - How To - REST API authentication using OAuth 2.0"style={{marginBottom:'15px'}}/>
1. Go to the **Data Sources** page from the ToolJet dashboard, select API category on sidebar and choose the **REST API** data source.
2. In the **Base URL** field, enter the base URL `https://www.googleapis.com/oauth2/v1/userinfo`; the base URL specifies the network address of the API service.
3. Select **Authentication** type as *OAuth 2.0*
4. Keep the default values for **Grant Type**, **Add Access Token To**, and **Header Prefix** i.e. *Authorization Code*, *Request Header*, and *Bearer* respectively.
5. Enter **Access Token URL**: `https://oauth2.googleapis.com/token`; this token allows users to verify their identity, and in return, receive a unique access token.
6. Enter the **Client ID** and **Client Secret** that we generated from the [Google Console](http://console.developers.google.com/).
7. In the **Scope** field, enter `https://www.googleapis.com/auth/userinfo.profile`; Scope is a mechanism in OAuth 2.0 to limit an application's access to a user's account. Check the scopes available for [Google OAuth2 API here](https://developers.google.com/identity/protocols/oauth2/scopes#oauth2).
8. Enter **Authorization URL:**`https://accounts.google.com/o/oauth2/v2/auth`; the Authorization URL requests authorization from the user and redirects to retrieve an authorization code from identity server.
9. Create three **Custom Authentication Parameters:**
1.**response_type**: code ( `code` refers to the Authorization Code)
2.**client_id**: Client ID
3.**redirect_url**: `http://localhost:8082/oauth2/authorize` if using ToolJet locally or enter this `https://app.tooljet.com/oauth2/authorize` if using ToolJet Cloud.
10. Keep the default selection for **Client Authentication** and **Save** the data source.
<imgclass="screenshot-full"src="/img/how-to/oauth2-authorization/restapi-v2.png"alt="ToolJet - How To - REST API authentication using OAuth 2.0"style={{marginBottom:'15px'}}/>
Let’s create a query to make a `GET` request to the URL, it will pop a new window and ask the user to authenticate against the API.
- Add a new query and select the REST API data source from the dropdown
- In the **Method** dropdown select `GET` and enable the `Run query on application load?`
- Run the query.
- A new window will pop for authentication and once auth is successful, you can run the query again to get the user data like Name and Profile Picture.
ToolJet’s REST API data source supports Bearer Token as the authentication type. Bearer Token is a security token that is issued by the authentication server to the client. The client then uses the token to access the protected resources hosted by the resource server.
1. Go to the **Data Sources** page from the ToolJet dashboard, select **API** category on sidebar and choose the **REST API** data source.
2. In the **Base URL** field, enter the base URL. The base URL specifies the network address of the API service. For example, `http://localhost:3001/api/bearer-auth`
3. Enter the **Headers** if required. Headers are key-value pairs to include as headers with REST API requests.
4. Select **Authentication** type as *Bearer* from the dropdown.
5. Enter the **Token** in the field. The token is a security token that is issued by the authentication server to the client. The client then uses the token to access the protected resources hosted by the resource server.
6. Now you have option to select the **SSL Certificate** if required. SSL certificate is used to verify the server certificate. By default, it is set to *None*. You can provide the **CA Certificate** or **Client Certificate** from the dropdown.
1.**CA Certificate**: Requires a CA certificate to verify the server certificate. Copy the content of `server.crt` file and paste it in the **CA Cert** field. `server.crt` file is the certificate file that is used to verify the server certificate.
2.**Client Certificate**: Requires a client certificate to authenticate with the server. **client.key**, **client.crt**, and **server.crt** files are the certificate files that are used to authenticate with the server. Copy the content of **client.key** file and paste it in the **Client Key** field. Copy the content of **client.crt** file and paste it in the **Client Cert** field. Copy the content of **server.crt** file and paste it in the **CA Cert** field.
<imgclassName="screenshot-full"src="/img/datasource-reference/rest-api/clientcert.png"alt="ToolJet - Data source - REST API"/>
