# `Tink.HTTPBehaviour`
[🔗](https://github.com/iamkanishka/tink.ex/blob/v0.1.1/lib/tink/http_behaviour.ex#L1)

Behaviour specification for HTTP client adapters.

This module defines the contract that HTTP adapters must implement to work
with Tink. By using a behaviour, we allow for easy swapping of HTTP
clients and simplified testing with mocks.

## Implementing a Custom Adapter

To create a custom HTTP adapter:

    defmodule MyApp.CustomHTTPAdapter do
      @behaviour Tink.HTTPBehaviour

      @impl true
      def request(method, url, body, headers, opts) do
        # Your implementation
      end

      @impl true
      def get(url, headers, opts), do: request(:get, url, nil, headers, opts)

      @impl true
      def post(url, body, headers, opts), do: request(:post, url, body, headers, opts)

      @impl true
      def put(url, body, headers, opts), do: request(:put, url, body, headers, opts)

      @impl true
      def patch(url, body, headers, opts), do: request(:patch, url, body, headers, opts)

      @impl true
      def delete(url, headers, opts), do: request(:delete, url, nil, headers, opts)
    end

Then configure Tink to use it:

    config :tink,
      http_adapter: MyApp.CustomHTTPAdapter

## Testing

For testing, you can use a mock adapter:

    defmodule MyApp.MockHTTPAdapter do
      @behaviour Tink.HTTPBehaviour

      @impl true
      def request(_method, _url, _body, _headers, _opts) do
        {:ok, %{status: 200, headers: [], body: %{"data" => "test"}}}
      end

      # Implement other callbacks...
    end

# `body`

```elixir
@type body() :: map() | String.t() | nil
```

# `error`

```elixir
@type error() :: %{type: atom(), reason: term()}
```

# `headers`

```elixir
@type headers() :: [{String.t(), String.t()}]
```

# `method`

```elixir
@type method() :: :get | :post | :put | :patch | :delete | :head | :options
```

# `opts`

```elixir
@type opts() :: keyword()
```

# `response`

```elixir
@type response() :: %{status: non_neg_integer(), headers: headers(), body: term()}
```

# `url`

```elixir
@type url() :: String.t()
```

# `delete`

```elixir
@callback delete(url(), headers(), opts()) :: {:ok, response()} | {:error, error()}
```

Performs an HTTP DELETE request.

## Parameters

  * `url` - Full URL to request
  * `headers` - List of header tuples
  * `opts` - Options including timeout, retries, etc.

## Returns

  * `{:ok, response}` - Successful response
  * `{:error, error}` - Request failed

## Examples

    {:ok, response} = adapter.delete(
      "https://api.tink.com/api/v1/credentials/cred123",
      [{"authorization", "Bearer token"}],
      timeout: 5000
    )

# `get`

```elixir
@callback get(url(), headers(), opts()) :: {:ok, response()} | {:error, error()}
```

Performs an HTTP GET request.

## Parameters

  * `url` - Full URL to request
  * `headers` - List of header tuples
  * `opts` - Options including timeout, retries, etc.

## Returns

  * `{:ok, response}` - Successful response
  * `{:error, error}` - Request failed

## Examples

    {:ok, response} = adapter.get(
      "https://api.tink.com/api/v1/providers",
      [{"authorization", "Bearer token"}],
      timeout: 5000
    )

# `patch`

```elixir
@callback patch(url(), body(), headers(), opts()) :: {:ok, response()} | {:error, error()}
```

Performs an HTTP PATCH request.

## Parameters

  * `url` - Full URL to request
  * `body` - Request body (map or string)
  * `headers` - List of header tuples
  * `opts` - Options including timeout, retries, etc.

## Returns

  * `{:ok, response}` - Successful response
  * `{:error, error}` - Request failed

# `post`

```elixir
@callback post(url(), body(), headers(), opts()) :: {:ok, response()} | {:error, error()}
```

Performs an HTTP POST request.

## Parameters

  * `url` - Full URL to request
  * `body` - Request body (map or string)
  * `headers` - List of header tuples
  * `opts` - Options including timeout, retries, etc.

## Returns

  * `{:ok, response}` - Successful response
  * `{:error, error}` - Request failed

## Examples

    {:ok, response} = adapter.post(
      "https://api.tink.com/api/v1/user/create",
      %{external_user_id: "user123"},
      [{"content-type", "application/json"}],
      timeout: 5000
    )

# `put`

```elixir
@callback put(url(), body(), headers(), opts()) :: {:ok, response()} | {:error, error()}
```

Performs an HTTP PUT request.

## Parameters

  * `url` - Full URL to request
  * `body` - Request body (map or string)
  * `headers` - List of header tuples
  * `opts` - Options including timeout, retries, etc.

## Returns

  * `{:ok, response}` - Successful response
  * `{:error, error}` - Request failed

# `request`

```elixir
@callback request(method(), url(), body(), headers(), opts()) ::
  {:ok, response()} | {:error, error()}
```

Performs an HTTP request with the specified method.

## Parameters

  * `method` - HTTP method (:get, :post, :put, :patch, :delete)
  * `url` - Full URL to request
  * `body` - Request body (map, string, or nil)
  * `headers` - List of header tuples
  * `opts` - Options including timeout, retries, etc.

## Returns

  * `{:ok, response}` - Successful response with status, headers, and body
  * `{:error, error}` - Request failed with error details

## Examples

    {:ok, response} = adapter.request(
      :get,
      "https://api.tink.com/api/v1/providers",
      nil,
      [{"authorization", "Bearer token"}],
      timeout: 5000
    )

---

*Consult [api-reference.md](api-reference.md) for complete listing*