# 3x-ui Country-Based Rules Middleware

This service fetches a JSON subscription from [3x-ui](https://github.com/MHSanaei/3x-ui) and merges it with country-specific routing rules stored in the `rules/` directory.

Examples:
* `rules/nl.json` is applied for clients detected in the **Netherlands**
* `rules/de.json` for **Germany**
* `rules/default.json` when no country-specific file exists

---

## Installation

*npm*

```bash
npm i @alltiptop/geoip-3xui-rules
```

---

## Usage

```typescript
import { createServer } from 'xui-json-client-rules';
import dotenv from 'dotenv';

dotenv.config();

const app = await createServer({
  upstreamUrl: process.env.UPSTREAM_URL!,     // URL of your 3x-ui instance
  secretUrl: process.env.SECRET_URL!,         // Secret path segment to hide the endpoint
  directSameCountry: true,                    // Direct same country as user by ip and domain
  rulesDir: 'rules',                          // Directory containing JSON rules
  logger: process.env.NODE_ENV !== 'production'
  xuiOptions: {                               // Opional settings for 3x-ui panel api
    panelAddress: process.env.XUI_PANEL_URL,  // 3x-ui panel address
    token: process.env.XUI_PANEL_TOKEN, // 3x-ui API token
    inboundIds: [process.env.XUI_INBOUND_ID], // inbounds list for users
    debug: process.env.NODE_ENV !== 'production',
  },
  // Optional: post-process the final merged JSON before it is sent
  transform: ({ json }) => {
    // Example: force warning log level and annotate remarks
    json.log = json.log || {};
    json.log.loglevel = 'warning';
    if (typeof json.remarks === 'string') json.remarks = `${json.remarks} [transformed]`;
    return json;
  },
});

app.listen({ port: 3088, host: '0.0.0.0' });
```

---

## Rule Files

A template is available in the `rules-template/` directory. Rule files follow the native Xray routing format: <https://xtls.github.io/en/config/routing.html>

* **`base.json`** – applied first, before any country-specific rules.
* **`default.json`** – fallback rules when no matching country file is found.
* **`XX.json`** – any ISO-3166-1 alpha-2 country code, such as `de`, `nl`, `us`, etc.
* **`tags/<tag>/base.json`** – mandatory file, applied first for every visitor who activates this tag.
* **`tags/<tag>/default.json`** – fallback for the tag when there is no country-specific override.
* **`tags/<tag>/<ISO>.json`** – tag override for a particular country (ISO-3166-1 alpha-2).  Example: `tags/streaming/US.json`.

### Tag presets (optional)

Tags let you quickly switch additional rule-packs on/off without creating separate subscriptions.  A tag becomes **active** when it is present **either** in the request URL **or** in the user’s comment inside 3x-ui:

```text
GET /<secret>/json/<subId>?tags=gaming,streaming    ← query parameter (comma list or repeated key)

// 3x-ui › User › comment field
tags=gaming,streaming; another=data                  ← semicolon/new-line separated, case-insensitive
```

The backend merges both sources, removes duplicates, then processes every active tag in the order they were discovered.

Create a directory per tag under `rules/tags/`.  The directory **must** contain `base.json`, and **optionally** `default.json` plus any number of country overrides:

```text
rules
├ base.json        # Global baseline rules (applied first)
├ default.json     # Fallback when no country match
├ us.json          # Country preset (USA)
├ eu.json          # Regional preset (European Union)
├ !de.json         # Reverse preset, applies to everyone except DE
├ !eu.json         # Reverse preset, applies to everyone NOT in the EU (isEU === false)
└─ tags/
   └─ streaming/
      ├─ base.json      # always loaded first
      ├─ default.json   # used when visitor’s country has no override
      ├─ us.json        # overrides for United States
      └─ de.json        # overrides for Germany
```

File loading order **per tag** (case-insensitive file names):
1. `base.json` – always first.
2. `XX.json` – matching the visitor’s ISO-3166 country code (e.g. `us.json`).
3. `default.json` – only when a country file is **not** found.

This allows you to keep shared logic in **base** while adding country-specific tweaks only where necessary.

### Rule application order (updated)

1. **Direct rule** – Routes requests to `publicURL` directly to avoid geo-misdetection during self-updates.
2. **`base.json`** – Global baseline for everyone.
3. **Tag presets** – For every active tag: `base.json` → country override (or `default.json`).
4. **Same-country rules** – If `directSameCountry` is enabled, traffic destined to the client’s own country goes direct.
5. **Reverse presets (exclude countries)** – Files named like `!fr.json` or `!fr,nl,de.json` (see below).
6. **Regional preset** – `eu.json` for EU visitors.
7. **Country preset** – Specific country file (e.g. `us.json`), or `default.json` when none exists.

---

## Reusable snippets with "@include"

You can keep common rule fragments in `rules/includes/*.json` and inline them in any rules file using a special string syntax:

```jsonc
// rules/includes/de-proxy.json
{
  "outboundTag": "direct",
  "domain": ["domain:de"],
  "enabled": true
}
```

Use it from another file (note the quotes around the include token):

```jsonc
// rules/default.json
[
  "@include de-proxy",
  {
    "outboundTag": "proxy",
    "ip": ["geoip:fr"],
    "enabled": true,
    "remarks": "GeoIP FR",
    "type": "field"
  }
]
```

Details:
- Place files under `rules/includes/`.
- Syntax: `"@include <name>"` or `"@include <name>.json"`.
- Includes are expanded recursively; circular references are ignored.
- Missing includes are replaced with `{}` (no-op object) to keep JSON valid.

---

## Reverse presets (exclude countries)

Sometimes you want a rule-set to apply to everyone except certain countries. Create files in `rules/` whose names start with `!`:

```text
rules/
├ !fr.json          # applies to all visitors whose ISO ≠ FR
├ !fr,nl,de.json    # applies to all visitors whose ISO ∉ {FR, NL, DE}
└ !eu.json          # applies to all visitors NOT in the EU (special token 'EU')
```

Each file contains a standard array of Xray `routing.rules` items. At request time, the middleware injects these rules if the visitor’s ISO-3166 country code is not in the exclude list.

Application order: after same-country rules and before regional/country presets (see order above).

---

## Country overrides via query params

You can override the detected country/EU status for testing or custom routing by passing query parameters to the JSON endpoint:

```text
?country=DE&isEU=true
```

- `country` – ISO-3166 alpha-2 code (case-insensitive), e.g. `de`, `US`.
- `isEU` – boolean accepted values: `true|false|1|0|yes|no|on|off`.

When provided, these values override the result from IP geolocation for the current request only.

---

## Transform hook

You can optionally provide a `transform` function in `createServer` options to modify the final JSON right before it is returned to the client.

Signature:

```ts
transform?: ({
  json: Record<string, unknown>,
  iso: string,
  subId: string,
  isEU?: boolean,
  query?: Record<string, string | string[] | undefined>,
}) => Record<string, unknown> | Promise<Record<string, unknown>>
```

Notes:
- Runs after merging upstream config, base/country/tag rules, overrides, reverse presets.
- If it throws, the original merged JSON is returned and the error is logged.
- Return the updated object; if you return `undefined`, the previous value is used.

Example:

```ts
const app = await createServer({
  // ...other options
  transform: async ({ json, iso, isEU }) => {
    // Drop stats section and ensure warning log level
    delete (json as any).stats;
    json.log = json.log || {};
    json.log.loglevel = 'warning';
    json.remarks = `${json.remarks || ''} [iso:${iso || '??'} eu:${Boolean(isEU)}]`;
    return json;
  },
});
```

---

## Why?

[3x-ui](https://github.com/MHSanaei/3x-ui) allows only one set of rules per subscription. This middleware automatically serves **different** rule sets based on the client’s IP country.