PG Dump API Reference

The PG Dump API is an admin-only endpoint that can be used to execute pg_dump on the Postgres instance that Hasura is configured with.

The primary motive of this API is to provide convenience methods to initialise migrations from an existing Hasura instance. But the functionality can be later expanded to do other things such as taking data dump etc.

Endpoint

All requests are POST requests to the /v1alpha1/pg_dump endpoint.

API Spec

Request

POST /v1alpha1/pg_dump HTTP/1.1
Content-Type: application/json
X-Hasura-Role: admin

{
  "opts": ["-O", "-x", "--schema-only", "--schema", "public"],
  "clean_output": true
}
  • opts: Arguments to be passed to the pg_dump tool. Represented as array of strings. The underlying command that is executed is:

    pg_dump $DATABASE_URL $OPTS -f $FILENAME
    
  • clean_output: When this optional argument is set to true, the output SQL from the command is cleaned to remove the following:

    • SQL front matter, like SET statements.
    • CREATE SCHEMA public.
    • COMMENT ON SCHMEA public is 'standard public schema';
    • Comments (--) and empty newlines.
    • Postgres triggers created by Hasura for event triggers.

Source code for the script that is executed can be found here.

Sample response

HTTP/1.1 200 OK
Content-Type: application/sql

CREATE TABLE public.author (
    id integer NOT NULL,
    name text NOT NULL
);
CREATE SEQUENCE public.author_id_seq
    AS integer
    START WITH 1
    INCREMENT BY 1
    NO MINVALUE
    NO MAXVALUE
    CACHE 1;
ALTER SEQUENCE public.author_id_seq OWNED BY public.author.id;
ALTER TABLE ONLY public.author ALTER COLUMN id SET DEFAULT nextval('public.author_id_seq'::regclass);

Disabling PG Dump API

Since this API can be used to dump all the Postgres data and schema, it can be disabled, especially in production deployments.

The enabled-apis flag or the HASURA_GRAPHQL_ENABLED_APIS env var can be used to enable/disable this API. By default, The PG DumpAPI is enabled. To disable it, you need to explicitly state that this API is not enabled. i.e. remove it from the list of enabled APIs.

# enable only graphql & metadata apis, disable pgdump
--enabled-apis="graphql,metadata"
HASURA_GRAPHQL_ENABLED_APIS="graphql,metadata"

See GraphQL engine server flags reference for info on setting the above flag/env var