GoGeoIP Web API

GoGeoIP - a lightweight web api providing ip intelligence written in GO. This software provides an api to get as many information as possible for a given IP address or the current visitor. This includes network, system, location and user information. A Live Demo is available under gogeoip.com.

Table of Contents

• Features
• Installation
  • GUI
• Configuration
  • HTTP & HTTPS
  • Letsencrypt
  • Middlewares & Extensions
  • Rate limiting & Quota management
  • MaxMind
  • ip2location
  • Tor Project
  • Logging
  • Memcache
  • Redis
  • Additional
• Database
• Api
  • Output
    • CSV
    • XML
    • JSON
    • JSONP
• Build
• Support
• Security
• Credits
• License

Features

• Serving over HTTPS (TLS) using your own certificates, or provisioned automatically using LetsEncrypt.org
• HSTS ready to restrict your browser clients to always use HTTPS
• Configurable read and write timeouts to avoid stale clients consuming server resources
• Reverse proxy ready
• Configurable CORS to restrict access to specific domains
• Configurable api prefix to serve the API alongside other APIs on the same host
• Optional round trip optimization by enabling TCP Fast Open
• Integrated rate limit (quota) for your clients (per client IP) based on requests per time interval; several backends such as in-memory map (for single instance), or redis or memcache for distributed deployments are supported
• Serve the default GeoLite2 City free database that is downloaded and updated automatically in background on a configurable schedule, or
• Serve the commercial GeoIP2 City database from MaxMind, either as a local file that you provide and update periodically (so the server can reload it), or configured to be downloaded periodically using your API key
• Serve the default PX8LITEBIN free database that is downloaded and updated automatically in background on a configurable schedule, or
• Serve the commercial PX8BIN database from ip2location, either as a local file that you provide and update periodically (so the server can reload it), or configured to be downloaded periodically using your API token
• Multiple languages are supported (en, ru, es, jp, fr, de)
• Detect VPN anonymizer, open proxies, web proxies, Tor exits, data center, web hosting (DCH) range and search engine robots (SES).
• Supports Linux, OS X, FreeBSD, and Windows
• Setup wizard

Requirements

A Free MaxMind and / or ip2location License will be required and can be easily obtained:

1. Sign up for a MaxMind account (no purchase required)
2. Set your password and create a license key
3. Sign up for a IP2Location account (no purchase required)
4. Create access token

Installation

Download and unpack a fitting pre-compiled binary or build a binary yourself by by following the build instructions.

Continue by configuring your application:

geoip \
    -mm-user-id 100000 \
    -mm-license-key 0AAaAaaAa0A0AAaA \
    -i2l-token 0BBbBbbBb0B0BBbB \
    -http=:8080 \
    -gui gui \
    -save

Open a browser and navigate to http://localhost:8080/ to verify everything is working.

Please take a look at the available options for further details.

GUI

An example GUI can be found under webklex/gogeoip-gui. It is already included in the pre-compiled packages found under releases.

Server Options

To see all the available options, use the -help option:

geoip -help

You can configure the web server via command line flags, the config file conf/settings.config or by using the -setup flag:

geoip -setup

HTTP & HTTPS

CLI	Config	Type	Default	Description
-http	HTTP	string	localhost:8080	Address in form of ip:port to listen
-https	HTTPS	string		Address in form of ip:port to listen
-write-timeout	WRITE_TIMEOUT	int	15000000000	Write timeout in nanoseconds for HTTP and HTTPS client connections
-read-timeout	READ_TIMEOUT	int	30000000000	Read timeout in nanoseconds for HTTP and HTTPS client connections
-tcp-fast-open	TCP_FAST_OPEN	bool	false	Enable TCP fast open
-tcp-naggle	TCP_NAGGLE	bool	false	Enable TCP Nagle's algorithm
-http2	HTTP2	bool	true	Enable HTTP/2 when TLS is enabled
-hsts	HSTS	string
-key	KEY	string	key.pem	X.509 key file for HTTPS server
-cert	CERT	string	cert.pem	X.509 certificate file for HTTPS server

Letsencrypt

CLI	Config	Type	Default	Description
-letsencrypt	LETSENCRYPT	bool	false	Enable automatic TLS using letsencrypt.org
-letsencrypt-email	LETSENCRYPT_EMAIL	string		Optional email to register with letsencrypt
-letsencrypt-hosts	LETSENCRYPT_HOSTS	string		Comma separated list of hosts for the certificate
-letsencrypt-cert-dir	LETSENCRYPT_CERT_DIR	string		Letsencrypt cert dir

Middlewares & Extensions

CLI	Config	Type	Default	Description
-use-x-forwarded-for	USE_X_FORWARDED_FOR	bool	false	Use the X-Forwarded-For header when available (e.g. behind proxy)
-cors-origin	CORS_ORIGIN	string	*	Comma separated list of CORS origins endpoints
-api-prefix	API_PREFIX	string	/	API endpoint prefix
-gui	GUI	string		Web gui directory

Rate limiting & Quota management

CLI	Config	Type	Default	Description
-quota-backend	QUOTA_BACKEND	string	redis	Backend for rate limiter: map, redis, or memcache
-quota-burst	QUOTA_BURST	int	3	Max requests per source IP per request burst
-quota-interval	QUOTA_INTERVAL	int	3600000000000	Quota expiration interval, per source IP querying the API in nanoseconds
-quota-max	QUOTA_MAX	int	1	"Max requests per source IP per interval; set 0 to turn quotas off

MaxMind

CLI	Config	Type	Default	Description
-mm-license-key	MM_LICENSE_KEY	string		MaxMind License Key
-mm-user-id	MM_USER_ID	string		MaxMind User ID
-mm-product-id	MM_PRODUCT_ID	string	GeoLite2-City	MaxMind Product ID
-mm-retry	MM_RETRY_INTERVAL	int	7200000000000	Max time to wait before retrying to download a MaxMind database
-mm-update	MM_UPDATE_INTERVAL	int	86400000000000	MaxMind database update check interval in nanoseconds
-mm-updates-host	MM_UPDATES_HOST	string	download.maxmind.com	MaxMind Updates Host

ip2location

CLI	Config	Type	Default	Description
-i2l-token	I2L_TOKEN	string		ip2location access token
-i2l-product-id	I2L_PRODUCT_ID	string	PX8LITEBIN	ip2location Product ID
-i2l-retry	I2L_RETRY_INTERVAL	int	7200000000000	Max time to wait before retrying to download a ip2location database
-i2l-update	I2L_UPDATE_INTERVAL	int	86400000000000	ip2location database update check interval in nanoseconds
-i2l-updates-host	I2L_UPDATES_HOST	string	www.ip2location.com	ip2location Updates Host

Tor Project

CLI	Config	Type	Default	Description
-tor-exit-check	TOR_EXIT	string	8.8.8.8	MaxMind Product ID
-tor-retry	TOR_RETRY_INTERVAL	int	7200000000000	Max time in nanoseconds to wait before retrying to download database
-tor-update	TOR_UPDATE_INTERVAL	int	86400000000000	Database update check interval in nanoseconds
-tor-updates-host	TOR_UPDATES_HOST	string	check.torproject.org	MaxMind Updates Host

Logging

CLI	Config	Type	Default	Description
-logtostdout	LOGTOSTDOUT	bool	false	Log to stdout instead of stderr
-log-file	LOG_FILE	string		Log file location
-logtimestamp	LOGTIMESTAMP	bool	true	Prefix non-access logs with timestamp

Memcache

CLI	Config	Type	Default	Description
-memcache	MEMCACHE	string	localhost:11211	Memcache address in form of host:port[,host:port] for quota
-memcache-timeout	MEMCACHE_TIMEOUT	int	1000000000	Memcache read/write timeout in nanoseconds

Redis

CLI	Config	Type	Default	Description
-redis	REDIS	string	localhost:6379	Redis address in form of host:port[,host:port] for quota
-redis-timeout	REDIS_TIMEOUT	int	1000000000	Redis read/write timeout in nanoseconds

Additional

CLI	Config	Type	Default	Description
-silent	SILENT	bool	false	Disable HTTP and HTTPS log request details
-config		string	conf/settings.config	Config file path
-setup		bool	false	Run the setup wizard
-save		bool	false	Save config
-version		bool	false	Show version and exit
-help		bool	false	Show help and exit

If you're using LetsEncrypt.org to provision your TLS certificates, you have to listen for HTTPS on port 443. Following is an example of the server listening on 2 different ports: http (80) and https (443):

geoip \
    -mm-user-id 100000 \
    -mm-license-key 0AAaAaaAa0A0AAaA \
    -i2l-token 0BBbBbbBb0B0BBbB \
    -http=:8080 \
    -https=:8443 \
    -hsts=max-age=31536000 \
    -letsencrypt \
    -letsencrypt-hosts=example.com \
    -gui gui \
    -save

$ cat conf/settings.config
{
    "MM_USER_ID": "100000",
    "MM_LICENSE_KEY": "0AAaAaaAa0A0AAaA",
    "HTTP": ":8080",
    "HTTPS": ":8443",
    "HSTS": "max-age=31536000",
    "LETSENCRYPT": true,
    "LETSENCRYPT_HOSTS": "example.com",
    ...

By default, HTTP/2 is enabled over HTTPS. You can disable by passing the -http2=false flag.

If the web server is running behind a reverse proxy or load balancer, you have to run it passing the -use-x-forwarded-for parameter and provide the X-Forwarded-For HTTP header in all requests. This is for the geoip web server be able to log the client IP, and to perform geolocation lookups when an IP is not provided to the API, e.g. /json/ (uses client IP) vs /json/1.2.3.4.

Databases

The current implementation uses the free GeoLite2 City database from MaxMind as well as the free IP2Proxy database from ip2location and the generic tor exit node list provided by the TorProject. If you have purchased the commercial database from MaxMind or ip2location, you can point the geoip web server or (Go API, for dev) to the URL containing the file, or local file, and the server will use it. In case of files on disk, you can replace the file with a newer version and the geoip web server will reload it automatically in background. If instead of a file you use a URL (the default), we periodically check the URL in background to see if there's a new database version available, then download the reload it automatically.

All responses from the geoip API contain the date that the database was downloaded in the X-Database-Date HTTP header.

API

The API is served by endpoints that encode the response in different formats. You can pass a different IP or hostname. For example, to lookup the geolocation of github.com the server resolves the name first, then uses the first IP address available, which might be IPv4 or IPv6:

curl :8080/json/{ip or hostname}?lang={language}[&user]

Same semantics are available for the /xml/{ip} and /csv/{ip} endpoints. JSON responses can be encoded as JSONP, by adding the callback parameter:

The used default language depends on the present Accept-Language header. You can define the used language by providing a lang parameter containing the two digit country code (en, ru, es, fr, de, jp).

Add the user parameter to the end to receive user device specific information. Please see the JSON example for output details.

Output

Network

Name	Value type	JSON	XML	CSV	Comment
IP address	string	ip	IP	0
Number (ASN)	integer	as.number	AS.Number	1
Organization	string	as.name	AS.Name	2
ISP name	string	isp	Isp	3
Domain	string	domain	Domain	4
TLDs	[]string	tld	Tld	5
Is bot	bool	bot	Bot	6
Is tor user	bool	tor	Tor	7
Is proxy user	bool	proxy	Proxy	8
Proxy type	string	proxy_type	ProxyType	9	Available proxy types
Last seen in days	integer	last_seen	LastSeen	10
Usage type	string	usage_type	UsageType	11	Available usage types

Location

Name	Value type	JSON	XML	CSV	Comment
Region code	string	region_code	RegionCode	12
Region name	string	region_name	RegionName	13
City name	string	city	City	14
Zip code	string	zip_code	ZipCode	15
Time zone	string	time_zone	TimeZone	16
Latitude	float	latitude	Latitude	17
Longitude	float	longitude	Longitude	18
Accuracy radius	integer	accuracy_radius	AccuracyRadius	19
Metro code	integer	metro_code	MetroCode	20
Country code	string	country.code	Country.Code	21
CIOC	string	country.cioc	Country.CIOC	22
CCN3	string	country.ccn3	Country.CCN3	23
Call codes	[]string	country.call_code	Country.CallCode	24
International call prefix	string	country.international_prefix	Country.InternationalPrefix	25
Country capital	string	country.capital	Country.Capital	26
Country name	string	country.name	Country.Name	27
Full country name	string	country.full_name	Country.FullName	28
Country Area km²	integer	country.area	Country.Area	29
Country borders	[]string	country.borders	Country.Borders	30
Latitude	float	country.latitude	Country.Latitude	31
Longitude	float	country.longitude	Country.Longitude	32
Max. Latitude	float	country.max_latitude	Country.MaxLatitude	33
Max. Longitude	float	country.max_longitude	Country.MaxLongitude	34
Min. Latitude	float	country.min_latitude	Country.MinLatitude	35
Min. Longitude	float	country.min_longitude	Country.MinLongitude	36
Currencies	[]{code,name}	country.currency	Country.Currency	37
Continent code	string	country.content.code	Country.Continent.Code	38
Continent name	string	country.content.name	Country.Continent.Name	39
Continent sub region	string	country.content.sub_region	Country.Continent.SubRegion	40

System

Name	Value type	JSON	XML	CSV	Comment
Operating System	string	os	OS	41
System architecture	string	os_version	OSVersion	42
Browser	string	browser	Browser	43
Browser Version	string	version	Version	44
Device name	string	device	Device	45
Is mobile user	bool	mobile	Mobile	46
Is tablet user	bool	tablet	Tablet	47
Is desktop user	bool	desktop	Desktop	48

User

Name	Value type	JSON	XML	CSV	Comment
Language	string	language.language	Language.Language	49
Language region	string	language.region	Language.Region	50
Language tag	string	language.tag	Language.Tag	51

CSV

curl :8080/csv/208.13.138.36

208.13.138.36,209,"CenturyLink Communications, LLC",,,.us,0,0,0,,0,,NV,,Las Vegas,839,89129,America/Los_Angeles,-115.2821,36.2473,20,US,USA,840,1,011,Washington D.C.,United States,United States of America,9372610.0000,CAN/MEX,39.4433,-98.9573,71.4411,-66.8854,17.8315,-179.2311,USD/USN/USS,,

curl :8080/csv/208.13.138.36?user

208.13.138.36,209,"CenturyLink Communications, LLC",,,.us,0,0,0,,0,,NV,,Las Vegas,839,89129,America/Los_Angeles,-115.2821,36.2473,20,US,USA,840,1,011,Washington D.C.,United States,United States of America,9372610.0000,CAN/MEX,39.4433,-98.9573,71.4411,-66.8854,17.8315,-179.2311,USD/USN/USS,,,Linux,Ubuntu Chromium,79.0.3945.79,x86_64,,0,0,1,en,US,en-US

XML

curl :8080/xml/208.13.138.36

<Response>
    <Network>
        <IP>208.13.138.36</IP>
        <AS>
            <Number>209</Number>
            <Name>CenturyLink Communications, LLC</Name>
        </AS>
        <Isp/>
        <Domain/>
        <Tld>.us</Tld>
        <Bot>false</Bot>
        <Tor>false</Tor>
        <Proxy>false</Proxy>
        <ProxyType/>
        <LastSeen>0</LastSeen>
        <UsageType/>
    </Network>
    <Location>
        <RegionCode>NV</RegionCode>
        <RegionName/>
        <City>Las Vegas</City>
        <ZipCode>89129</ZipCode>
        <TimeZone>America/Los_Angeles</TimeZone>
        <Longitude>-115.2821</Longitude>
        <Latitude>36.2473</Latitude>
        <AccuracyRadius>20</AccuracyRadius>
        <MetroCode>839</MetroCode>
        <Country>
            <Code>US</Code>
            <CIOC>USA</CIOC>
            <CCN3>840</CCN3>
            <CallCode>1</CallCode>
            <InternationalPrefix>011</InternationalPrefix>
            <Capital>Washington D.C.</Capital>
            <Name>United States</Name>
            <FullName>United States of America</FullName>
            <Area>9.37261e+06</Area>
            <Borders>CAN</Borders>
            <Borders>MEX</Borders>
            <Latitude>39.443256</Latitude>
            <Longitude>-98.95734</Longitude>
            <MaxLatitude>71.441055</MaxLatitude>
            <MaxLongitude>-66.885414</MaxLongitude>
            <MinLatitude>17.831509</MinLatitude>
            <MinLongitude>-179.23108</MinLongitude>
            <Currency>
                <Code>USD</Code>
                <Name/>
            </Currency>
            <Currency>
                <Code>USN</Code>
                <Name/>
            </Currency>
            <Currency>
                <Code>USS</Code>
                <Name/>
            </Currency>
            <Continent>
                <Code/>
                <Name>North America</Name>
                <SubRegion/>
            </Continent>
        </Country>
    </Location>
</Response>

curl :8080/xml/208.13.138.36?user

<Response>
    <Network>
        <IP>208.13.138.36</IP>
        <AS>
            <Number>209</Number>
            <Name>CenturyLink Communications, LLC</Name>
        </AS>
        <Isp/>
        <Domain/>
        <Tld>.us</Tld>
        <Bot>false</Bot>
        <Tor>false</Tor>
        <Proxy>false</Proxy>
        <ProxyType/>
        <LastSeen>0</LastSeen>
        <UsageType/>
    </Network>
    <Location>
        <RegionCode>NV</RegionCode>
        <RegionName/>
        <City>Las Vegas</City>
        <ZipCode>89129</ZipCode>
        <TimeZone>America/Los_Angeles</TimeZone>
        <Longitude>-115.2821</Longitude>
        <Latitude>36.2473</Latitude>
        <AccuracyRadius>20</AccuracyRadius>
        <MetroCode>839</MetroCode>
        <Country>
            <Code>US</Code>
            <CIOC>USA</CIOC>
            <CCN3>840</CCN3>
            <CallCode>1</CallCode>
            <InternationalPrefix>011</InternationalPrefix>
            <Capital>Washington D.C.</Capital>
            <Name>United States</Name>
            <FullName>United States of America</FullName>
            <Area>9.37261e+06</Area>
            <Borders>CAN</Borders>
            <Borders>MEX</Borders>
            <Latitude>39.443256</Latitude>
            <Longitude>-98.95734</Longitude>
            <MaxLatitude>71.441055</MaxLatitude>
            <MaxLongitude>-66.885414</MaxLongitude>
            <MinLatitude>17.831509</MinLatitude>
            <MinLongitude>-179.23108</MinLongitude>
            <Currency>
                <Code>USD</Code>
                <Name/>
            </Currency>
            <Currency>
                <Code>USN</Code>
                <Name/>
            </Currency>
            <Currency>
                <Code>USS</Code>
                <Name/>
            </Currency>
            <Continent>
                <Code/>
                <Name>North America</Name>
                <SubRegion/>
            </Continent>
        </Country>
    </Location>
    <System>
        <OS>Linux</OS>
        <Browser>Ubuntu Chromium</Browser>
        <Version>79.0.3945.79</Version>
        <OSVersion>x86_64</OSVersion>
        <Device/>
        <Mobile>false</Mobile>
        <Tablet>false</Tablet>
        <Desktop>true</Desktop>
    </System>
    <User>
        <Language>
            <Language>en</Language>
            <Region>US</Region>
            <Tag>en-US</Tag>
        </Language>
    </User>
</Response>

JSON

curl :8080/json/208.13.138.36

{
  "network": {
    "ip": "208.13.138.36",
    "as": {
      "number": 209,
      "name": "CenturyLink Communications, LLC"
    },
    "isp": "",
    "domain": "",
    "tld": [".us"],
    "bot": false,
    "tor": false,
    "proxy": false,
    "proxy_type": "",
    "last_seen": 0,
    "usage_type": ""
  },
  "location": {
    "region_code": "NV",
    "region_name": "",
    "city": "Las Vegas",
    "zip_code": "89129",
    "time_zone": "America/Los_Angeles",
    "longitude": -115.2821,
    "latitude": 36.2473,
    "accuracy_radius": 20,
    "metro_code": 839,
    "country": {
      "code": "US",
      "cioc": "USA",
      "ccn3": "840",
      "call_code": ["1"],
      "international_prefix": "011",
      "capital": "Washington D.C.",
      "name": "United States",
      "full_name": "United States of America",
      "area": 9372610,
      "borders": ["CAN", "MEX"],
      "latitude": 39.443256,
      "longitude": -98.95734,
      "max_latitude": 71.441055,
      "max_longitude": -66.885414,
      "min_latitude": 17.831509,
      "min_longitude": -179.23108,
      "currency": [{
          "code": "USD",
          "name": ""
       }, {
          "code": "USN",
          "name": ""
       }, {
          "code": "USS",
          "name": ""
      }],
      "continent": {
        "code": "",
        "name": "North America",
        "sub_region": ""
      }
    }
  }
}

curl :8080/json/208.13.138.36?user

{
  "network": {
    "ip": "208.13.138.36",
    "as": {
      "number": 209,
      "name": "CenturyLink Communications, LLC"
    },
    "isp": "",
    "domain": "",
    "tld": [".us"],
    "bot": false,
    "tor": false,
    "proxy": false,
    "proxy_type": "",
    "last_seen": 0,
    "usage_type": ""
  },
  "location": {
    "region_code": "NV",
    "region_name": "",
    "city": "Las Vegas",
    "zip_code": "89129",
    "time_zone": "America/Los_Angeles",
    "longitude": -115.2821,
    "latitude": 36.2473,
    "accuracy_radius": 20,
    "metro_code": 839,
    "country": {
      "code": "US",
      "cioc": "USA",
      "ccn3": "840",
      "call_code": ["1"],
      "international_prefix": "011",
      "capital": "Washington D.C.",
      "name": "United States",
      "full_name": "United States of America",
      "area": 9372610,
      "borders": ["CAN", "MEX"],
      "latitude": 39.443256,
      "longitude": -98.95734,
      "max_latitude": 71.441055,
      "max_longitude": -66.885414,
      "min_latitude": 17.831509,
      "min_longitude": -179.23108,
      "currency": [{
          "code": "USD",
          "name": ""
       }, {
          "code": "USN",
          "name": ""
       }, {
          "code": "USS",
          "name": ""
      }],
      "continent": {
        "code": "",
        "name": "North America",
        "sub_region": ""
      }
    }
  },
  "system": {
    "os": "Linux",
    "browser": "Ubuntu Chromium",
    "version": "79.0.3945.79",
    "os_version": "x86_64",
    "device": "",
    "mobile": false,
    "tablet": false,
    "desktop": true
  },
  "user": {
    "language": {
      "language": "en",
      "region": "US",
      "tag": "en-US"
    }
  }
}

JSONP

curl :8080/json/208.13.138.36?callback=foobar

foobar({
 "network": {
   "ip": "208.13.138.36",
   "as": {
     "number": 209,
     "name": "CenturyLink Communications, LLC"
   },
   "isp": "",
   "domain": "",
   "tld": [".us"],
   "bot": false,
   "tor": false,
   "proxy": false,
   "proxy_type": "",
   "last_seen": 0,
   "usage_type": ""
 },
 "location": {
   "region_code": "NV",
   "region_name": "",
   "city": "Las Vegas",
   "zip_code": "89129",
   "time_zone": "America/Los_Angeles",
   "longitude": -115.2821,
   "latitude": 36.2473,
   "accuracy_radius": 20,
   "metro_code": 839,
   "country": {
     "code": "US",
     "cioc": "USA",
     "ccn3": "840",
     "call_code": ["1"],
     "international_prefix": "011",
     "capital": "Washington D.C.",
     "name": "United States",
     "full_name": "United States of America",
     "area": 9372610,
     "borders": ["CAN", "MEX"],
     "latitude": 39.443256,
     "longitude": -98.95734,
     "max_latitude": 71.441055,
     "max_longitude": -66.885414,
     "min_latitude": 17.831509,
     "min_longitude": -179.23108,
     "currency": [{
         "code": "USD",
         "name": ""
      }, {
         "code": "USN",
         "name": ""
      }, {
         "code": "USS",
         "name": ""
     }],
     "continent": {
       "code": "",
       "name": "North America",
       "sub_region": ""
     }
   }
 }
});

The callback parameter is ignored on all other endpoints.

Build

You can build your own binaries by calling build.sh

build.sh build_dir

Features & pull requests

Everyone can contribute to this project. Every pull request will be considered but it can also happen to be declined. To prevent unnecessary work, please consider to create a feature issue first, if you're planning to do bigger changes. Of course you can also create a new feature issue if you're just wishing a feature ;)

Off topic, rude or abusive issues will be deleted without any notice.

Support

If you encounter any problems or if you find a bug, please don't hesitate to create a new issue. However please be aware that it might take some time to get an answer.

If you need immediate or commercial support, feel free to send me a mail at [email protected].

Change log

Please see CHANGELOG for more information what has changed recently.

Security

If you discover any security related issues, please email [email protected] instead of using the issue tracker.

Credits

• Webklex
• All Contributors

License

The MIT License (MIT). Please see License File for more information.