/ 
DBIO-0.900000
/ DBIO::Deploy::Base

NAME

DBIO::Deploy::Base - Base class for DBIO driver deploy orchestrators

VERSION

version 0.900000

DESCRIPTION

Base class for the per-driver Deploy orchestrators (DBIO::PostgreSQL::Deploy, DBIO::MySQL::Deploy, DBIO::DuckDB::Deploy, DBIO::SQLite::Deploy). Those classes implement the same test-deploy-and-compare strategy and their install/apply/upgrade methods were byte-near-identical; only the way diff obtains the target model (deploy the desired schema into a throwaway database and introspect it) is genuinely engine-specific.

This base hosts the shared orchestration:

  • "install" -- generate install DDL and run it against the live db.

  • "apply" -- run a diff's SQL against the live db.

  • "upgrade" -- "diff" then "apply".

  • "diff" -- introspect the live db (source), build the target model, and hand both to the driver's diff class.

against a handful of hooks. A subclass must provide the three class-name hooks ("_ddl_class", "_introspect_class", "_diff_class") and "_build_target_model" -- the "make a throwaway, deploy the desired schema, introspect it" step that is the real engine seam. Drivers that use a temporary database (PostgreSQL, MySQL) get a ready-made "_build_target_model" by subclassing DBIO::Deploy::Base::TempDatabase instead; in-memory drivers (DuckDB, SQLite) override "_build_target_model" directly with a :memory: connection.

ATTRIBUTES

schema

A connected DBIO::Schema instance using the driver's component. Required.

METHODS

new

my $deploy = $class->new(schema => $connected_schema, %extra);

Blesses the argument hash. schema is required.

_ddl_class

Class name whose install_ddl($schema) returns the install DDL. Abstract.

_introspect_class

Class name whose new(dbh => $dbh)->model returns an introspected model. Abstract.

_diff_class

Class name whose new(source => $m, target => $m) returns a diff object (responding to has_changes and as_sql). Abstract.

_new_introspect

my $intro = $self->_new_introspect($dbh);

Factory for an introspector over $dbh. Default: _introspect_class->new(dbh => $dbh). Override to pass extra construction args (e.g. PostgreSQL's schema_filter).

_introspect_current

The introspected model of the live (source) database. Default: $self->_new_introspect($self->_dbh)->model.

_install_ddl

The install DDL string for the connected schema. Default: _ddl_class->install_ddl($self->schema).

_execute_ddl

$self->_execute_ddl($dbh, $sql);

Splits $sql into statements ("_split_statements" in DBIO::SQL::Util) and runs each via $dbh->do, skipping comment-only statements.

_build_target_model

The desired-state model: deploy the install DDL into a throwaway database and introspect it. Abstract here -- provided by DBIO::Deploy::Base::TempDatabase for temp-database drivers, or overridden directly by in-memory drivers.

install

$deploy->install;

Generates the install DDL and executes it against the connected database. Suitable for a fresh install on an empty database. Returns true.

diff

my $diff = $deploy->diff;

Introspects the live database (source), builds the target model via "_build_target_model", and returns _diff_class->new(source => ..., target => ...).

apply

$deploy->apply($diff);

Executes each statement of $diff->as_sql against the connected database. No-op (returns false) when $diff->has_changes is false.

upgrade

my $diff = $deploy->upgrade;

Convenience: "diff" then "apply". Returns the diff object if changes were applied, or undef if the database was already up to date.

AUTHOR

DBIO & DBIx::Class Authors

COPYRIGHT AND LICENSE

Copyright (C) 2026 DBIO Authors Portions Copyright (C) 2005-2025 DBIx::Class Authors Based on DBIx::Class, heavily modified.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.