Add EU endpoint support and update README

Add optional baseUrl constructor parameter so users can target the EU
endpoint (eu-api.ipdata.co) or any custom URL. Export EU_BASE_URL
constant. Update README with EU endpoint docs and response fields
reference for company, carrier, and threat objects.

https://claude.ai/code/session_01UabaLo3R3sXovyxaZo2yCF

Author: claude

README.md

@@ -10,8 +10,10 @@ JavaScript library that can be used in a web browser or Node.js application to g
 - [Use](#use)
   - [Import Library](#import-library)
   - [Create an Instance](#create-an-instance)
+  - [EU Endpoint](#eu-endpoint)
   - [Lookup](#lookup)
   - [Bulk Lookup](#bulk-lookup)
+- [Response Fields](#response-fields)
 
 ## Install
 
@@ -62,6 +64,22 @@ const cacheConfig = {
 const ipdata = new IPData('<apiKey>', cacheConfig);
 ```
 
+### EU Endpoint
+
+By default requests are routed to the global endpoint (`https://api.ipdata.co`). To ensure end user data stays in the EU, pass the EU endpoint as the third parameter.
+
+```js
+import IPData, { EU_BASE_URL } from 'ipdata';
+
+const ipdata = new IPData('<apiKey>', undefined, EU_BASE_URL);
+```
+
+You can also pass a custom base URL if needed.
+
+```js
+const ipdata = new IPData('<apiKey>', undefined, 'https://eu-api.ipdata.co/');
+```
+
 ### Lookup
 
 The library will lookup the ip address of the host computer if no ip address is provided.
@@ -131,3 +149,15 @@ ipdata.bulkLookup(ips, fields)
     // ...
   });
 ```
+
+## Response Fields
+
+The following fields are available for use with `selectField` and `fields` parameters:
+
+`ip`, `is_eu`, `city`, `region`, `region_code`, `country_name`, `country_code`, `continent_name`, `continent_code`, `latitude`, `longitude`, `asn`, `company`, `postal`, `calling_code`, `flag`, `emoji_flag`, `emoji_unicode`, `carrier`, `languages`, `currency`, `time_zone`, `threat`, `count`
+
+The `company` field returns an object with `name`, `domain`, `network`, and `type` properties.
+
+The `carrier` field returns an object with `name`, `mcc`, and `mnc` properties.
+
+The `threat` field returns an object with `is_tor`, `is_icloud_relay`, `is_proxy`, `is_datacenter`, `is_anonymous`, `is_known_attacker`, `is_known_abuser`, `is_threat`, `is_bogon`, and `blocklists` properties.

src/ipdata.test.ts

@@ -1,5 +1,5 @@
 import keyBy from 'lodash/keyBy';
-import IPData from './ipdata';
+import IPData, { EU_BASE_URL } from './ipdata';
 
 const TEST_IP = '1.1.1.1';
 const DEFAULT_IP_KEY = 'DEFAULT_IP';
@@ -29,6 +29,16 @@ describe('constructor()', () => {
     expect(ipdata.cache.max).toEqual(max);
     expect(ipdata.cache.maxAge).toEqual(maxAge);
   });
+
+  it('should use the default base URL', () => {
+    const ipdata = new IPData(process.env.IPDATA_API_KEY as string);
+    expect(ipdata.baseUrl).toEqual('https://api.ipdata.co/');
+  });
+
+  it('should accept a custom base URL', () => {
+    const ipdata = new IPData(process.env.IPDATA_API_KEY as string, undefined, EU_BASE_URL);
+    expect(ipdata.baseUrl).toEqual('https://eu-api.ipdata.co/');
+  });
 });
 
 describe('lookup()', () => {

src/ipdata.ts

@@ -37,6 +37,7 @@ const VALID_FIELDS = [
   'status',
 ];
 const BASE_URL = 'https://api.ipdata.co/';
+export const EU_BASE_URL = 'https://eu-api.ipdata.co/';
 
 function isValidIP(ip: string): boolean {
   return ip === DEFAULT_IP || isIP(ip);
@@ -146,20 +147,22 @@ interface IPDataParams {
 
 export default class IPData {
   apiKey: string;
+  baseUrl: string;
   cache: LRU<string, LookupResponse>;
 
-  constructor(apiKey: string, cacheConfig?: CacheConfig) {
+  constructor(apiKey: string, cacheConfig?: CacheConfig, baseUrl?: string) {
     if (!isString(apiKey)) {
       throw new Error('An API key is required.');
     }
 
     this.apiKey = apiKey;
+    this.baseUrl = baseUrl || BASE_URL;
     this.cache = new LRU<string, LookupResponse>({ max: CACHE_MAX, maxAge: CACHE_MAX_AGE, ...cacheConfig });
   }
 
   async lookup(ip?: string, selectField?: string, fields?: string[]): Promise<LookupResponse> {
     const params: IPDataParams = { 'api-key': this.apiKey };
-    let url = ip ? urljoin(BASE_URL, ip) : BASE_URL;
+    let url = ip ? urljoin(this.baseUrl, ip) : this.baseUrl;
 
     if (ip && !isValidIP(ip)) {
       throw new Error(`${ip} is an invalid IP address.`);
@@ -227,7 +230,7 @@ export default class IPData {
 
     try {
       if (bulk.length > 0) {
-        const response = await axios.post(urljoin(BASE_URL, 'bulk'), bulk, { params });
+        const response = await axios.post(urljoin(this.baseUrl, 'bulk'), bulk, { params });
         response.data.forEach(info => {
           this.cache.set(info.ip, { ...info, status: response.status });
           responses.push(this.cache.get(info.ip));