express-iplogger

A simple IP logger library for Express using ip-api.com

( Not affiliated )

Installation:

$ npm install express-iplogger --save

Usage

You can use the logger by calling the imported logger inside an express route/middleware. The logger result is accessible using the ipinfo object from the request parameter.

ip-api.com limits the request from an IP address to 45 requests per second, so to avoid getting rate limited here you can specify how long do you want the logger to cache the result from ip-api.com.

You can set it to 0 to disable caching(not reccomended).

const express = require('express');
const logger = require('express-iplogger');

const app = express();
const options = {
	cacheAge: 120 // 120 seconds
}

app.use(logger(options));
app.use((req, res) => {
	res.send('Hello world!');
	console.log(req.ipinfo); // Result from the ip logger
});

app.listen(3000);

IMPORTANT: If you are running this behind a reverse proxy like nginx you should add add this line of code before you use the logger in the middleware:

app.set('trust proxy', true);

This line of code will set the req.ip object to either the socketAddress's client IP or the IP from the X-Forwarded-For header. For example in nginx you can do:

server {
	listen 80;

	location / {
		proxy_set_header X-Forwarded-For $remote_addr;
		proxy_pass http://localhost:3000/;
	}
}

Full explanation:

Nginx forwards the client IP($remote_addr) to the express webserver behind the proxy by adding the X-Forwarded-For header
By setting 'trust proxy' in express app to true, you are "trusting" the proxy's X-Forwarded-For header. Therefore, express sets the req.ip object to X-Forwarded-For header if exists, else it'll just return the reverse proxy's IP
This req.ip object is required in order for the middleware to work. That is the way this library retrieves the IP.

Warning: setting 'trust proxy' to true will trust any X-Forwarded-For header including the one from the client! Only enable this option when using a reverse proxy!

Options

Key	Description	Type
cacheAge	How long do you want the API result to be cached in seconds (Set to 0 to disable caching)	number

Result (req.ipinfo):

Returns null when there's an error. Otherwise:

Key	Description	Example	Type
IP	The client's IP address	139.56.37.243	string
continent	Continent name	North America	string
continentCode	Two-letter continent code	NA	string
country	Country name	United States	string
countryCode	Two-letter country code ISO 3166-1 alpha-2	US	string
regionName	Region/state	California	string
region	Region/state short code (FIPS or ISO)	CA or 10	string
city	City	Mountain View	string
district	District(subdivision of city)	Old Farm District	string
zip	Zip code	94043	string
lat	Latitude of the IP address's location in decimal degrees	37.4192	float
lon	Longtitude of the IP address's location in decimal degrees	-122.0574	float
timezone	Timezone(tz)	America/Los_Angeles	string
offset	Timezone UTC DST offset in seconds	-25200	integer
currency	Three-letter national currency code ISO 4217	USD	string
isp	Internet Service Provider name	Google	string
org	Organization name	Google	string
as	AS number and organization, seperated by space(RIR). Empty for IP blocks not being announced in BGP tables	AS15169 Google Inc.	string
asname	AS name(RIR). Empty for IP blocks not being announced in BGP tables	AS15169 Google Inc.	string
reverse	Reverse DNS of the IP	wi-in-f94.1e100.net	string
mobile	Movile(cellular) connection	true	boolean
proxy	Proxy, VPN or Tor exit address	true	boolean
hosting	Hosting, colocated or data center	false	boolean

License

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

MIT License