feat(kno-3079): idempotency keys for workflow triggers

CHANGELOG.md

@@ -0,0 +1,3 @@
+## v0.4.7
+
+* Add support for `idempotency_key` on workflow triggers

lib/knock.ex

@@ -88,5 +88,5 @@ defmodule Knock do
   @doc """
   Issues a notify call, triggering a workflow with the given key.
   """
-  defdelegate notify(client, key, properties), to: Knock.Workflows, as: :trigger
+  defdelegate notify(client, key, properties, options), to: Knock.Workflows, as: :trigger
 end

lib/knock/api.ex

@@ -34,7 +34,7 @@ defmodule Knock.Api do
   @spec put(Client.t(), String.t(), map(), options()) :: response()
   def put(client, path, body, opts \\ []) do
     client
-    |> http_client()
+    |> http_client(opts)
     |> Tesla.put(path, body, opts)
     |> handle_response()
   end
@@ -45,7 +45,7 @@ defmodule Knock.Api do
   @spec post(Client.t(), String.t(), map(), options()) :: response()
   def post(client, path, body, opts \\ []) do
     client
-    |> http_client()
+    |> http_client(opts)
     |> Tesla.post(path, body, opts)
     |> handle_response()
   end
@@ -77,17 +77,22 @@ defmodule Knock.Api do
   """
   def library_version, do: @lib_version
 
-  defp http_client(config) do
+  defp http_client(config, opts \\ []) do
     middleware = [
       {Tesla.Middleware.BaseUrl, config.host <> "/v1"},
       {Tesla.Middleware.JSON, engine: config.json_client},
       {Tesla.Middleware.Headers,
        [
          {"Authorization", "Bearer " <> config.api_key},
          {"User-Agent", "knocklabs/knock-elixir@#{library_version()}"}
-       ]}
+       ] ++ maybe_idempotency_key_header(Map.new(opts))}
     ]
 
     Tesla.client(middleware, config.adapter)
   end
+
+  defp maybe_idempotency_key_header(%{idempotency_key: key}) when is_binary(key),
+    do: [{"Idempotency-Key", key}]
+
+  defp maybe_idempotency_key_header(_), do: []
 end

lib/knock/resources/workflows.ex

@@ -8,10 +8,13 @@ defmodule Knock.Workflows do
   Executes a notify call for the workflow with the given key.
 
   Note: properties must contain at least `recipents` for the call to be valid.
+
+  Options can include:
+  * `idempotency_key`: A unique key to prevent duplicate requests
   """
-  @spec trigger(Knock.Client.t(), String.t(), map()) :: Api.response()
-  def trigger(client, key, properties) do
-    Api.post(client, "/workflows/#{key}/trigger", properties)
+  @spec trigger(Knock.Client.t(), String.t(), map(), keyword()) :: Api.response()
+  def trigger(client, key, properties, options \\ []) do
+    Api.post(client, "/workflows/#{key}/trigger", properties, options)
   end
 
   @doc """

mix.exs

@@ -2,7 +2,7 @@ defmodule Knock.MixProject do
   use Mix.Project
 
   @source_url "https://github.com/knocklabs/knock-elixir"
-  @version "0.4.6"
+  @version "0.4.7"
 
   def project do
     [