# Appendix A – Integration with symlink use case

**Actors:**

User, User Portal, Spark Gateway

**Preconditions:**

User Portal:
- Have user credentials in plain text.

Spark Gateway:
- Configure password in gateway.conf.
- Allow IP addresses of User Portal to access the Spark Gateway API (Optional, [Admin Manual 3.25](https://docs.sparkview.info/books/sparkview-admin-manual/page/325-usb-redirection)).
- Create RDP servers with config.html or HTTP API ([Integration Guide 4.1](https://docs.sparkview.info/books/sparkview-integration-guide/page/41-http-api)), and make it as a white list.
- Allow symlink access only by setting symlinkOnly = true in gateway.conf. Server id or address will not be allowed to create a connection.
- Disable VNC access by setting vnc = false in gateway.conf (SSH, Telnet are disabled by default).

Basic flow:
1. User login to User Portal.
2. (optional) User Portal create a server on Spark Gateway with HTTP API if that server is not created yet:<br>http://gatewayAddress/SERVER?id=serverId&displayName=Name&server=hostName&gatewayPwd=passwordInGateway.conf&...; Check if server exists: http://wthink/SERVER?action=list&gatewayPwd=21232f297a57a5a743894a0e4a801fc3&id=serverId;<br>The gateway will return HTTP Status code 500 and {"error:": "not found"} in JSON format.
3. User Portal create a symlink on Spark Gateway with HTTP API:<br>'http://gatewayAddress/SYMLINK?symlink=symlinkId&server=existingServerId&validTime=8h&gatewayPwd=passwordInGateway.conf&parameters=' + encodeURIComponent('user=domainUser&pwd=domainPassword&domain=domain');
4. User portal construct a connection link and display it to user:<br>http://gateway/rdpdirect.html?symlink=symlinkId&displayName=nameOnBrowserTitle; or use the Spark View JS library directly to create a connection:<br>`var rdp = new svGlobal.Rdp(‘wss://gateway/RDP?symlink=symlinkId&..’, width, height, color);`
5. User click the link and connect.
6. User portal delete the symlink when user exist or close the browser:<br>http://gatewayAddress/SYMLINK?symlink=symlinkId&action=delete

**Pros:**
- Easy and secure.
- Symlink will be invalid or deleted and it cannot be reused by other.
- No need to send the user credential to the browser side.

**Cons:**
- User domain credentials need to be sent to the gateway in plain text.