0.5.4

Marten 0.5.4 fixes a couple of bugs.

Bug fixes

• Fix possible undefined constant compilation error when using file schema fields.
• Fix CSRF token request data parameter not being used when the method of POST requests is overridden with the Method Override middleware.

0.5.3

Marten 0.5.3 fixes a couple of bugs.

Bug fixes

• Fix query prefetcher not systematically using unscoped queries when prefetching relation records.
• Fix possible case sensitivity issue when specifying HTTP method names supported by specific handlers.
• Fix inconsistent callback name in the password update handler generated for the authentication application.

0.5.2

Marten 0.5.2 fixes a couple of bugs.

Bug fixes

• Fix text template name of emails generated through the use of the email generator.
• Fix non-existing error when the new management command was used to generate an app structure with the --with-auth option.
• Fix missing "emails" folder requirement in projects generated with the new management command.
• Fix how nested routes are displayed when invoking the routes management command.
• Fix settings namespace generation for top-level Settings settings classes.

0.5.1

Marten 0.5.1 fixes a couple of bugs.

Bug fixes

• Fix duplicated #create_user spec helper method in projects generated with the authentication application.
• Fix excessive verbosity when running management commands.
• Fix non-working hash/array methods in templates.
• Fix an issue where unknown variable exceptions are not raised when accessing unsupported attributes on custom template objects.
• Make sure the cookie session store always defines an expiry when signing the session data.

0.5.0

Marten 0.5 is here! This major version adds substantial enhancements to the framework like the ability to leverage pre-fetched relations in query sets, model scopes, enum fields for models and schemas, raw SQL predicates, and more!

Requirements and compatibility

• Crystal: 1.11, 1.12, and 1.13.
• Databases:
  • MariaDB 10.4 and higher.
  • MySQL 8.0.11 and higher.
  • PostgreSQL 12 and higher.
  • SQLite 3.27.0 and higher.

New features

Relations pre-fetching

Marten now provides the ability to prefetch relations when using query sets through the use of the new #prefetch method. When using #prefetch, the records corresponding to the specified relationships will be prefetched in single batches and each record returned by the original query set will have the corresponding related objects already selected and populated.

For example:

posts_1 = Post.all.to_a
# hits the database to retrieve the related "tags" (many-to-many relation)
puts posts_1[0].tags.to_a

posts_2 = Post.all.prefetch(:tags).to_a
# doesn't hit the database since the related "tags" relation was already prefetched
puts posts_2[0].tags.to_a

Like the existing #join method, this allows to alleviate N+1 issues commonly encountered when accessing related objects. However, unlike #join (which can only be used with single-valued relationships), #prefetch can be used with both single-valued relationships and multi-valued relationships (such as many-to-many relationships, reverse many-to-many relationships, and reverse many-to-one relationships).

Please refer to Pre-fetching relations to learn more about this new capability.

Model scopes

It is now possible to define scopes in model classes. Scopes allow to pre-define specific filtered query sets, which can be easily applied to model classes and model query sets.

Such scopes can be defined through the use of the #scope macro, which expects a scope name (string literal or symbol) as first argument and requires a block where the query set filtering logic is defined:

class Post < Marten::Model
  field :id, :big_int, primary_key: true, auto: true
  field :title, :string, max_size: 255
  field :is_published, :bool, default: false
  field :created_at, :date_time

  scope :published { filter(is_published: true) }
  scope :unpublished { filter(is_published: false) }
  scope :recent { filter(created_at__gt: 1.year.ago) }
end

Post.published # => Post::QuerySet [...]>

It is also possible to override the default scope through the use of the #default_scope macro. This macro requires a block where the query set filtering logic is defined:

class Post < Marten::Model
  field :id, :big_int, primary_key: true, auto: true
  field :title, :string, max_size: 255
  field :is_published, :bool, default: false
  field :created_at, :date_time

  default_scope { filter(is_published: true) }
end

Please refer to Scopes for more details on how to define scopes.

Enum field for models and schemas

It is now possible to define enum fields in models and schemas. For models, such fields allow you to store valid enum values, with validation enforced at the database level. When validating data with schemas, they allow you to expect valid string values that match those of the configured enum.

For example:

enum Category
  NEWS
  BLOG
end

class Article < Marten::Model
  field :id, :big_int, primary_key: true, auto: true
  field :category, :enum, values: Category
end

article = Article.last!
article.category # => Category::BLOG

Raw SQL predicate filtering

Marten now provides the ability to filter query sets using raw SQL predicates through the use of the #filter method. This is useful when you want to leverage the flexibility of SQL for specific conditions, but still want Marten to handle the column selection and query building for the rest of the query.

For example:

Author.filter("first_name = :first_name", first_name: "John")
Author.filter("first_name = ?", "John")
Author.filter { q("first_name = :first_name", first_name: "John") }

Please refer to Filtering with raw SQL predicates to learn more about this new capability.

Minor features

Models and databases

• A new #pks method was introduced for query sets to make it easy to retrieve the primary key values of the model records targeted by a given current query set.
• A #count method is now available on model classes and provides the same functionality as the #count query set method.
• A new #bulk_create method was introduced to make it easy to insert multiple model instances into the database in a single query (which can be useful when dealing with large amounts of data that need to be inserted into the database).
• A new #average method was introduced to allow computing the average values of a specific model field at the database level for the records targeted by a specific query set.
• A new #sum method was introduced to allow computing the sum of the values of a specific model field at the database level for the records targeted by a specific query set.
• It is now possible to compute the minimum and maximum values of a specific field at the database level for the records targeted by a query set through the use of the #minimum and #maximum methods.
• The in query set predicate now supports filtering on arrays of model records directly.
• Query sets now provide a #to_sql method allowing to retrieve the corresponding SQL representation.
• Query sets can now be combined using the AND and OR binary operators. This can be achieved through the use of the & and | query set methods.
• Invalid record exceptions (instances of Marten::DB::Errors::InvalidRecord) now provide more details regarding the actual errors of the associated record.
• Creations of records from many-to-one reverse relation query sets are now scoped to the related record. See Many-to-one relationships for more details.
• A new #build method was introduced to make it possible to initialize new model instances from query sets.

Handlers and HTTP

• The #render helper method and the generic handlers that involve template renderings now automatically insert the request object in the template context.
• The Marten::Handlers::RecordDetail, Marten::Handlers::RecordUpdate, and Marten::Handlers::RecordDelete generic handle...

0.4.5

Marten 0.4.5 fixes a couple of bugs.

Bug fixes

• Fix a possible compilation error with custom settings namespace generation.
• Ensure that the serve management command recompiles projects upon translation file changes.
• Fix the order of asset finders to ensure that those associated with configured asset directories (via the assets.dirs setting) have priority over those associated with application directories.

0.4.4

Marten 0.4.4 fixes a couple of bugs.

Bug fixes

• Fix possible SQL syntax errors occurring when using in predicates with empty arrays.

0.4.3

Marten 0.4.3 fixes a couple of bugs.

Bug fixes

• Ensure that request query parameters can be accessed from templates.
• Fix hidden folders being ignored by the collectassets management command.
• Fix some ameba warnings in generated projects and applications.
• Fix inconsistency of #using method definitions between model classes and query sets.
• Fix missing DB-specific requirements in generated projects.

0.4.2

Marten 0.4.2 fixes a couple of bugs.

Bug fixes

• Fix a possible syntax error in the SQL queries generated for SQLite databases when running migrations.

0.4.1

Marten 0.4.1 fixes a couple of bugs.

Bug fixes

• Fix the position of the config/routes.cr file requirement in the src/project.cr file of generated projects.