https://github.com/williamthome/changeset

An OTP library to validate data based on Ecto changeset library (Elixir).
https://github.com/williamthome/changeset

changeset erlang erlang-library rebar3 validate validation-library

Last synced: about 1 month ago
JSON representation

An OTP library to validate data based on Ecto changeset library (Elixir).

• Host: GitHub
• URL: https://github.com/williamthome/changeset
• Owner: williamthome
• License: apache-2.0
• Created: 2023-05-18T05:16:17.000Z (over 1 year ago)
• Default Branch: main
• Last Pushed: 2023-10-13T22:01:08.000Z (about 1 year ago)
• Last Synced: 2024-05-01T17:21:39.697Z (8 months ago)
• Topics: changeset, erlang, erlang-library, rebar3, validate, validation-library
• Language: Erlang
• Homepage:
• Size: 109 KB
• Stars: 3
• Watchers: 1
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Funding: .github/FUNDING.yml
  • License: LICENSE

Awesome Lists containing this project

README

        
# changeset

An OTP library to validate data based on Ecto changeset library (Elixir).

## Disclaimer

This is a WIP library. The code may change at any time without notice.

## Example

Take this simple module:

```erlang

-module(movie).

-export([changeset/1, changeset/2]).

-define(TYPES,     #{name => binary, starring => binary}).

-define(PERMITTED, maps:keys(?TYPES)).

-define(REQUIRED,  [name]).

changeset(Params) ->

    changeset(#{}, Params).

changeset(Data, Params) ->

    Changeset = changeset:cast({Data, ?TYPES}, Params, ?PERMITTED),

    changeset:pipe(Changeset, [

        changeset:validate_required(?REQUIRED)

        % More validators here, e.g.:

        % changeset:validate_change(name, fun(_Name) -> [] end)

        % changeset:validate_format(name, "^[A-Z]")

        % changeset:validate_member(starring, [<<"Mike">>, <<"Joe">>, <<"Robert">>])

        % changeset:validate_not_member(starring, [<<"Me">])

    ]).

```

Now running

```shell

rebar3 shell

```

we can type the following:

```erlang

% The name is missing, the changeset will be invalid

1> movie:changeset(#{}).

{changeset,[],

           #{name => binary,starring => binary},

           [name],

           #{},#{},

           [{name,{<<"is required">>,#{validation => is_required}}}],

           [undefined,<<>>]}

% The name is not a binary, the changeset will be invalid

2> movie:changeset(#{name => foo}).

{changeset,[],

           #{name => binary,starring => binary},

           [name],

           #{},

           #{name => foo},

           [{name,{<<"must be a binary">>,#{validation => is_binary}}}],

           [undefined,<<>>]}

% The name is present and it's a binary, then the changeset will be valid

3> movie:changeset(#{name => <<"Erlang: The Movie">>}).

{changeset,[],

           #{name => binary,starring => binary},

           [name],

           #{},

           #{name => <<"Erlang: The Movie">>},

           [],

           [undefined,<<>>]}

% Get the valid changes

4> changeset:get_changes(v(3)).

#{name => <<"Erlang: The Movie">>}

```

## Struct

Currently, this is the changeset record

```erlang

-record(changeset,

    { fields       = []                :: [field()]

    , types        = #{}               :: #{field() := type()}

    , required     = []                :: [field()]

    , data         = #{}               :: #{field() => term()}

    , changes      = #{}               :: #{field() => term()}

    , errors       = []                :: [error()]

    , empty_values = [undefined, <<>>] :: nonempty_list()

    }).

```

and this are the available field types:

```erlang

-type type() :: atom

              | binary

              | bitstring

              | boolean

              | float

              | function

              | {function, arity()}

              | integer

              | list

              | map

              | pid

              | port

              | record

              | {record, Name :: atom()}

              | {record, Name :: atom(), Size :: non_neg_integer()}

              | reference

              | tuple

              .

```

The types are auto validated by the cast function.