Modelist

CLI and API to test and analyze ActiveRecord models.

Setup

In your Rails 3+ project, add this to your Gemfile:

gem 'modelist'

Then run:

bundle install

API Configuration

Not needed for CLI. Just used if you are using as an API:

Modelist::quiet = true

Usage

CLI

Modelist has a command-line interface with options to test for required circular dependencies, models that the specified models require due to nullable or validation constraints, or to test attributes and associations.

Circular

Check ActiveRecord circular dependencies. Find circular chains of dependencies where foreign keys that are not primary keys of the models are all not nullable in the schema or not nullable because of ActiveRecord presence validation with:

bundle exec modelist circular

or:

bundle exec modelist circular my_model_1 my_model_2 --output-file=/path/to/errors.log

Example output:

The following non-nullable foreign keys used in ActiveRecord model associations are involved in circular dependencies:

beers.waitress_id -> waitresses.bartender_id -> bartenders.beer_id -> beers.waitress_id

beers.waitress_id -> waitresses.bartender_id -> bartenders.order_id -> order.beer_id -> beers.waitress_id


Distinct foreign keys involved in a circular dependency:

beers.waitress_id
order.beer_id
bartenders.beer_id
bartenders.order_id
waitresses.bartender_id


Foreign keys by number of circular dependency chains involved with:

2 (out of 2): beers.waitress_id -> waitresses
2 (out of 2): waitresses.bartender_id -> bartenders
1 (out of 2): order.beer_id -> beers
1 (out of 2): bartenders.order_id -> order
1 (out of 2): bartenders.beer_id -> beers

Specify --output-file to provide an pathname of an errors file.

Required

Find the models that the specified models have non-nullable or presence validations for directly and indirectly. You can use this to determine which models are really required with:

bundle exec modelist required my_model_1 my_model_2

Example output:

Required models:

Bartender
Beer
Order
Waitress

Test

Test ActiveRecord models, their attributes, and associations with:

bundle exec modelist test

or:

bundle exec modelist test my_model_1 my_model_2 --output-file=/path/to/errors.log

Example output:

(...example data from models and attributes...)
---


FAILED: MyModel

---
MyModel.last.some_associations: PG::Error: ERROR:  operator does not exist: character varying = integer
LINE 1: ...oobars"  WHERE "foobars"."my_model_id" = 7
                                    ^
(...continued and backtrace...)
---
(...more errors...)


Passed (258):
---
AnotherGoodModel
GoodModel
...

Warnings (123):
---
Foo.first was nil. Assuming there is no data in the associated table, but please verify.
Bar's belongs_to :waitresses may need to be singularized to waitress?
...

Failed (85):
---
Bar
Foobar
MyModel

Specify --output-file to provide an pathname of an errors file.

Search

Given a (partial) model/tablename/column/association name, finds all matching models/associations:

bundle exec modelist search partial_search_string

Example output:

Models:
  Foo (table: foos)
  Foobar (table: foobars)
Associations:
  Bar (table: bars), association: foo (macro: belongs_to, options: {})
  Loo (table: loos), association: f_users (macro: has_one, options: {:foreign_key=>:foo_id})

Path Finder

Given two model names will find known paths:

bundle exec modelist paths my_model_1 my_model_2 

Example output:

checking for path from foobar to barfoo...
+++++++-+-++--+------

Paths from foobar to barfoo (2):

foobar.foo -> foo.barfoos -> barfoo

foobar.barfoo -> barfoo

API

Modelist::Analyst.find_required_models(:model1, :model2)
Modelist::CircularRefChecker.test_models(:model1, :model2, output_file: true)
Modelist::Tester.test_models(:model1, :model2, output_file: true)
Modelist::Searcher.find_all('foo')
Modelist::PathFinder.find_all(:model1, :model2)

License

Copyright (c) 2012-2013 Gary S. Weaver, released under the MIT license.