An implementation of RFC 6902 in pure Elixir.
Features:
- Creating a patch by comparing to maps and lists
- Apply patches to maps and lists - supports operations:
- add
- replace
- remove
- copy
- move
- test
- Escaping of "
/" (by "~1") and "~" (by "~0") - Allow usage of
-for appending things to list (Add and Copy operation) - Smart list diffing with
object_hashfor efficient patches on collections with unique identifiers
The package can be installed by adding jsonpatch to your list of dependencies in mix.exs:
def deps do
[
{:jsonpatch, "~> 2.2"}
]
endThe docs can be found at https://hexdocs.pm/jsonpatch.
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)
[
%{path: "/married", value: true, op: "replace"},
%{path: "/hobbies/2", op: "remove"},
%{path: "/hobbies/1", op: "remove"},
%{path: "/hobbies/0", value: "Elixir!", op: "replace"},
%{path: "/age", value: 33, op: "add"}
]Use object_hash to generate efficient patches for lists of objects with unique identifiers, producing minimal operations instead of cascading replacements.
iex> original = [
%{id: 1, name: "Alice"},
%{id: 2, name: "Bob"}
]
iex> updated = [
%{id: 99, name: "New"},
%{id: 1, name: "Alice"},
%{id: 2, name: "Bob"}
]
# Traditional pairwise diff - multiple replace operations
# >> Jsonpatch.diff(original, updated)
[
%{op: "add", path: "/2", value: %{id: 2, name: "Bob"}}
%{op: "replace", path: "/0", value: %{id: 99, name: "New"}},
%{op: "replace", path: "/1", value: %{id: 1, name: "Alice"}},
]
# With object_hash - single add operation
iex> Jsonpatch.diff(original, updated, object_hash: fn %{id: id} -> id end)
[
%{op: "add", path: "/0", value: %{id: 99, name: "New"}}
]iex> patch = [
%{op: "add", path: "/age", value: 33},
%{op: "replace", path: "/hobbies/0", value: "Elixir!"},
%{op: "replace", path: "/married", value: true},
%{op: "remove", path: "/hobbies/1"},
%{op: "remove", path: "/hobbies/2"}
]
iex> target = %{"name" => "Bob", "married" => false, "hobbies" => ["Sport", "Elixir", "Football"]}
iex> Jsonpatch.apply_patch(patch, target)
{:ok, %{"name" => "Bob", "married" => true, "hobbies" => ["Elixir!"], "age" => 33}}