pg_headerkit: PostgREST Header Kit

A set of functions for adding special features to your application that use PostgREST API calls to your PostgreSQL database. These functions can be used inside PostgreSQL functions that can give your application the following capabilities at the database level:

• rate limiting
• IP allowlisting
• IP denylisting
• request logging
• request filtering
• request routing
• user allowlisting by uid or email (Supabase-specific)
• user denylisting by uid or email (Supabase-specific)

Article

See: PostgREST Header Hacking

Function Reference

function	description	parameters	returns
hdr.headers()	get all header values as a json object	none	json object
hdr.header(item text)	get a header value	item (text)	text
hdr.ip()	get the ip address of the current user	none	text
hdr.allow_list()	get the allow list of ip addresses	none	inet[] (array of ip addresses)
hdr.deny_list()	get the deny list of ip addresses	none	inet[] (array of ip addresses)
hdr.in_deny_list(ip inet)	determine if the given ip is in the deny list	ip (inet)	boolean
hdr.in_allow_list(ip inet)	determine if the given ip is in the allow list	ip (inet)	boolean
hdr.in_deny_list()	determine if the current user's ip is in the deny list	none	boolean
hdr.in_allow_list()	determine if the current user's ip is in the allow list	none	boolean
hdr.host()	get host, i.e. "localhost:3000"	none	text
hdr.origin()	get origin, i.e. "http://localhost:8100"	none	text
hdr.referer()	get referer, i.e. "http://localhost:8100/"	none	text
hdr.agent()	get user-agent string	none	text
hdr.client()	get x-client-info, i.e. "supabase-js/1.35.7"	none	text
hdr.role()<br>hdr.consumer()	get role (consumer), i.e. "anon-key"	none	text
hdr.api_host()<br>hdr.domain()	get api server, i.e. "xxxxxxxxxxxxxxxx.supabase.co"	none	text
hdr.projectref()<br>hdr.ref()	get project ref #, i.e. "xxxxxxxxxxxxxxxx"	none	text
hdr.is_mobile()	is mobile?	none	boolean
hdr.is_iphone()	is iphone?	none	boolean
hdr.is_ipad()	is ipad?	none	boolean
hdr.is_android()	is android?	none	boolean