Crudry v1.0.0 Crudry.Resolver View Source
Generates CRUD functions to DRY Absinthe Resolvers.
Requires a previously generated Context.
Usage
To generate CRUD functions for a given schema resolver, simply do
defmodule MyApp.MyResolver do
alias MyApp.Repo
alias MyApp.MyContext
alias MyApp.MySchema
require Crudry.Resolver
Crudry.Resolver.generate_functions MyContext, MySchema
end
And the resolver will become
defmodule MyApp.MyResolver do
alias MyApp.Repo
alias MyApp.MyContext
alias MyApp.MySchema
require Crudry.Resolver
def get_my_schema(%{id: id}, _info) do
MyContext.get_my_schema(id)
|> nil_to_error(fn record -> {:ok, record} end)
end
def list_my_schemas(_args, _info) do
MyContext.list_my_schemas()
end
def create_my_schema(%{params: params}, _info) do
MyContext.create_my_schema(params)
end
def update_my_schema(%{id: id, params: params}, _info) do
MyContext.get_my_schema(id)
|> nil_to_error(fn record -> MyContext.update_my_schema(record, params) end)
end
def delete_my_schema(%{id: id}, _info) do
MyContext.get_my_schema(id)
|> nil_to_error(fn record -> MyContext.delete_my_schema(record) end)
end
# If `result` is `nil`, return an error. Otherwise, apply `func` to the `result`.
def nil_to_error(result, func) do
case result do
nil -> {:error, "MySchema not found."}
%{} = record -> func.(record)
end
end
end
Now, suppose the update resolver for our schema should update not only the schema but also some of its associations.
defmodule MyApp.Resolver do
alias MyApp.Repo
alias MyApp.MyContext
alias MyApp.MySchema
require Crudry.Resolver
Crudry.Resolver.generate_functions MyContext, MySchema, except: [:update]
def update_my_schema(%{id: id, params: params}, _info) do
MyContext.get_my_schema(id)
|> nil_to_error(fn record -> MyContext.update_my_schema_with_assocs(record, params, [:assoc]) end)
end
end
By using the nil_to_error
function, we DRY the nil checking and also ensure the error message is the same as the other auto-generated functions.
Link to this section Summary
Functions
Sets default options for the resolver
Generates CRUD functions for the schema_module
resolver
Link to this section Functions
default(opts) View Source (macro)
Sets default options for the resolver.
Options
:only
- list of functions to be generated. If not empty, functions not specified in this list are not generated. Default to[]
.:except
- list of functions to not be generated. If not empty, only functions not specified in this list will be generated. Default to[]
.The accepted values for
:only
and:except
are:[:get, :list, :create, :update, :delete]
.
Examples
iex> Crudry.Resolver.default only: [:create, :list]
:ok
iex> Crudry.Resolver.default except: [:get!, :list, :delete]
:ok
generate_functions(context, schema_module, opts \\ []) View Source (macro)
Generates CRUD functions for the schema_module
resolver.
Custom options can be given. To see the available options, refer to the documenation of Crudry.Resolver.default/1
.
Examples
Suppose we want to implement basic CRUD functionality for a User resolver, assuming there is an Accounts context which already implements CRUD functions for User.
defmodule MyApp.AccountsResolver do
require Crudry.Resolver
Crudry.Resolver.generate_functions Accounts, Accounts.User
end
Now, all this functionality is available:
AccountsResolver.get_user(%{id: id}, info)
AccountsResolver.list_users(_args, info)
AccountsResolver.crete_user(%{params: params}, info)
AccountsResolver.update_user(%{id: id, params: params}, info)
AccountsResolver.delete_user(%{id: id}, info)
AccountsResolver.nil_to_error(result, func)