Limited Links

Limited links is a feature that allows you to restrict the number of devices that can add a subscription (link) to the application. In your personal account on the happ-proxy.com website, you specify your subscription URL, set the maximum number of devices, and click "Generate link." The resulting link can be shared with a user, and you can be confident that the subscription can only be installed on the specified number of devices — exceeding the limit is impossible.

You can create limited links both through the web interface and via API.

Creating via Website

1. On the creation page, specify the unencrypted URL of your subscription.

2. Set the installation limit (maximum number of devices).

3. After generation:

   • The InstallID parameter is automatically added to the URL.

   • The link domain is stored in the database as a SHA-256 hash (raw domains are not stored to enhance security).

You will receive an encrypted link with the InstallID parameter.

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Creating via API

Send a GET request to:

https://api.happ-proxy.com/api/add-install?
  provider_code={provider_code}&
  auth_key={auth_key}&
  install_limit={install_limit}

• {provider_code} — your provider code (in your profile)

• {auth_key} — authorization key (in your profile)

• {install_limit} — maximum number of devices

API Response

• Success

  {
    "rc": 1,
    "msg": "Ok",
    "install_code": "6P0hVao1fG5e"
  }

• Error

  {
    "rc": 0,
    "msg": "Error description"
  }

Add the received install_code to the link as the InstallID parameter.

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Example

• Original URL:

  https://url.com/sub

• Final link:

  https://url.com/sub#Your_TITLE?installid=Abcd1234

Tip: Encrypt the link so users cannot remove the InstallID parameter.

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How It Works

When adding a link, the application calculates the SHA-256 hash of the domain and sends a request to:

https://check.happ-proxy.com/install?id={domain_hash}&installid={InstallID}

The response returns ProviderID and link status.

If the request fails to send (e.g., due to website blocking), the application will automatically retry after establishing a VPN connection.

The happ-proxy.com server receives the device's HWID and responds positively if the installation limit for the link has not been exceeded. If the limit is exceeded, the server returns a refusal and the application displays the message: &#xNAN;"The subscription administrator has restricted access. Please contact technical support."