Phoenix
Phoenix v1.7.0-rc.3

View Source mix phx.gen.context (Phoenix v1.7.0-rc.3)

Generates a context with functions around an Ecto schema.

$ mix phx.gen.context Accounts User users name:string age:integer

The first argument is the context module followed by the schema module and its plural name (used as the schema table name).

The context is an Elixir module that serves as an API boundary for the given resource. A context often holds many related resources. Therefore, if the context already exists, it will be augmented with functions for the given resource.

Note: A resource may also be split over distinct contexts (such as Accounts.User and Payments.User).

The schema is responsible for mapping the database fields into an Elixir struct.

Overall, this generator will add the following files to lib/your_app:

  • a context module in accounts.ex, serving as the API boundary
  • a schema in accounts/user.ex, with a users table

A migration file for the repository and test files for the context will also be generated.

generating-without-a-schema

 Generating without a schema

In some cases, you may wish to bootstrap the context module and tests, but leave internal implementation of the context and schema to yourself. Use the --no-schema flags to accomplish this.

table

 table

By default, the table name for the migration and schema will be the plural name provided for the resource. To customize this value, a --table option may be provided. For example:

$ mix phx.gen.context Accounts User users --table cms_users

binary_id

 binary_id

Generated migration can use binary_id for schema's primary key and its references with option --binary-id.

default-options

 Default options

This generator uses default options provided in the :generators configuration of your application. These are the defaults:

config :your_app, :generators,
  migration: true,
  binary_id: false,
  sample_binary_id: "11111111-1111-1111-1111-111111111111"

You can override those options per invocation by providing corresponding switches, e.g. --no-binary-id to use normal ids despite the default configuration or --migration to force generation of the migration.

Read the documentation for phx.gen.schema for more information on attributes.

skipping-prompts

 Skipping prompts

This generator will prompt you if there is an existing context with the same name, in order to provide more instructions on how to correctly use phoenix contexts. You can skip this prompt and automatically merge the new schema access functions and tests into the existing context using --merge-with-existing-context. To prevent changes to the existing context and exit the generator, use --no-merge-with-existing-context.