# Jsonpatch
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A implementation of [RFC 6902](https://tools.ietf.org/html/rfc6902) in pure Elixir.


Features:

1. Creating a patch by comparing to maps and structs
2. Apply patches to maps and structs - supports operations:
    - add
    - replace
    - remove
    - copy
    - move
    - test
3. De/Encoding and mapping 


## Usage

### Create a diff

```elixir
iex> source = %{"name" => "Bob", "married" => false, "hobbies" => ["Sport", "Elixir", "Football"]}
iex> destination = %{"name" => "Bob", "married" => true, "hobbies" => ["Elixir!"], "age" => 33}
iex> Jsonpatch.diff(source, destination)
{:ok, [
  %Jsonpatch.Operation.Add{path: "/age", value: 33},
  %Jsonpatch.Operation.Replace{path: "/hobbies/0", value: "Elixir!"},
  %Jsonpatch.Operation.Replace{path: "/married", value: true},
  %Jsonpatch.Operation.Remove{path: "/hobbies/1"},
  %Jsonpatch.Operation.Remove{path: "/hobbies/2"}
]}
```

### Mapping for de and encoding

Map a JSON patch struct to a regular map.

```elixir
iex> add_patch_map = %Jsonpatch.Operation.Add{path: "/name", value: "Alice"}
iex> Jsonpatch.Mapper.to_map(add_patch_map)
%{op: "add", path: "/name", value: "Alice"}
```

Map a regular map to a JSON patch struct.

```elixir
iex> add_patch_map = %{"op" => "add", "path" => "/name", "value" => "Alice"}
iex> Jsonpatch.Mapper.from_map(add_patch_map)
%Jsonpatch.Operation.Add{path: "/name", value: "Alice"}
```

### Apply patches

```elixir
iex> patch = [
  %Jsonpatch.Operation.Add{path: "/age", value: 33},
  %Jsonpatch.Operation.Replace{path: "/hobbies/0", value: "Elixir!"},
  %Jsonpatch.Operation.Replace{path: "/married", value: true},
  %Jsonpatch.Operation.Remove{path: "/hobbies/1"},
  %Jsonpatch.Operation.Remove{path: "/hobbies/2"}
]
iex> target = %{"name" => "Bob", "married" => false, "hobbies" => ["Sport", "Elixir", "Football"]}
iex> Jsonpatch.apply_patch(patch, target)
%{"name" => "Bob", "married" => true, "hobbies" => ["Elixir!"], "age" => 33}
```


## Installation

If [available in Hex](https://hex.pm/docs/publish), the package can be installed
by adding `jsonpatch` to your list of dependencies in `mix.exs`:

```elixir
def deps do
  [
    {:jsonpatch, "~> 0.9.1"}
  ]
end
```

Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
be found at [https://hexdocs.pm/jsonpatch](https://hexdocs.pm/jsonpatch).

## Important sources
- [Official RFC 6902](https://tools.ietf.org/html/rfc6902)
- [Inspiration: python-json-patch](https://github.com/stefankoegl/python-json-patch)