SQL::Translator::Parser::OpenAPI - convert OpenAPI schema to SQL::Translator schema


  use SQL::Translator;
  use SQL::Translator::Parser::OpenAPI;

  my $translator = SQL::Translator->new;

  # or...
  $ sqlt -f OpenAPI -t MySQL <my-openapi.json >my-mysqlschema.sql


This module implements a SQL::Translator::Parser to convert a JSON::Validator::OpenAPI specification to a SQL::Translator::Schema.

It uses, from the given API spec, the given "definitions" to generate tables in an RDBMS with suitable columns and types.

To try to make the data model represent the "real" data, it applies heuristics:

  • to remove object definitions that only have one property (which the author calls "thin objects"), or that have two properties, one of whose names has the substring "count" (case-insensitive).

  • for definitions that have allOf, either merge them together if there is a discriminator, or absorb properties from referred definitions

  • to find object definitions that have all the same properties as another, and remove all but the shortest-named one

  • to remove object definitions whose properties are a strict subset of another

  • creates object definitions for any properties that are an object

  • creates object definitions for any properties that are an array of simple OpenAPI types (e.g. string)

  • creates object definitions for any objects that are additionalProperties (i.e. freeform key/value pairs), that are key/value rows

  • absorbs any definitions that are in fact not objects, into the referring property

  • injects foreign-key relationships for array-of-object properties, and creates many-to-many tables for any two-way array relationships


None at present.



Standard as per SQL::Translator::Parser. The input $data is a scalar that can be understood as a JSON::Validator specification.


Given a hashref that is a JSON pointer to an OpenAPI spec's /definitions, returns a hashref that maps each definition name to a bitmask. The bitmask is set from each property name in that definition, according to its order in the complete sorted list of all property names in the definitions. Not exported. E.g.

  # properties:
  my $defs = {
    d1 => {
      properties => {
        p1 => 'string',
        p2 => 'string',
    d2 => {
      properties => {
        p2 => 'string',
        p3 => 'string',
  my $mask = SQL::Translator::Parser::OpenAPI::defs2mask($defs);
  # all prop names, sorted: qw(p1 p2 p3)
  # $mask:
    d1 => (1 << 0) | (1 << 1),
    d2 => (1 << 1) | (1 << 2),



Under /definitions/$defname, a key of x-view-of will name another definition (NB: not a full JSON pointer). That will make $defname not be created as a table. The handling of creating the "view" of the relevant table is left to the CRUD implementation. This gives it scope to use things like the current requesting user, or web parameters, which otherwise would require a parameterised view. These are not widely available.


Under /definitions/$defname/properties/$propname, a key of x-artifact with a true value will indicate this is not to be stored, and will not cause a column to be created. The value will instead be derived by other means. The value of this key may become the definition of that derivation.


Under /definitions/$defname/properties/$propname, a key of x-input-only with a true value will indicate this is not to be stored, and will not cause a column to be created. This may end up being merged with x-artifact.


To debug, set environment variable SQLTP_OPENAPI_DEBUG to a true value.


Ed J, <etj at>


Copyright (C) Ed J

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.