change the structure of image ttl parsar

docs/config/howto_set_richmedia_cache_ttl_based_on_image.md

@@ -4,7 +4,7 @@
 Richmedia are cached without the ttl but the rich media may have image which can expire, like aws signed url.
 In such cases the old image url (expired) is returned from the media cache.
 
-So to avoid such situation we can define a moddule that will set ttl based no image.
+So to avoid such situation we can define a moddule that will set ttl based on image.
 
 The module must have a `run` function and it should be registered in the config.
 

lib/pleroma/web/rich_media/parser.ex

@@ -35,17 +35,17 @@ defmodule Pleroma.Web.RichMedia.Parser do
   @doc """
   Set the rich media cache based on the expiration time of image.
 
-  Define a module that has `run` function
+  Adopt behaviour `Pleroma.Web.RichMedia.Parser.TTL`
 
   ## Example
 
       defmodule MyModule do
-        def run(data, url) do
+        @behaviour Pleroma.Web.RichMedia.Parser.TTL
+        def ttl(data, url) do
           image_url = Map.get(data, :image)
           # do some parsing in the url and get the ttl of the image
-          # ttl is unix time
-          ttl = parse_ttl_from_url(image_url)  
-          Cachex.expire_at(:rich_media_cache, url, ttl * 1000)
+          # and return ttl is unix time
+          parse_ttl_from_url(image_url)
         end
       end
 
@@ -55,22 +55,26 @@ defmodule Pleroma.Web.RichMedia.Parser do
         ttl_setters: [MyModule]
   """
   def set_ttl_based_on_image({:ok, data}, url) do
-    case Cachex.ttl(:rich_media_cache, url) do
-      {:ok, nil} ->
-        modules = Pleroma.Config.get([:rich_media, :ttl_setters])
-
-        if Enum.count(modules) > 0 do
-          Enum.each(modules, & &1.run(data, url))
-        end
-
+    with {:ok, nil} <- Cachex.ttl(:rich_media_cache, url) do
+      ttl = get_ttl_from_image(data, url)
+      Cachex.expire_at(:rich_media_cache, url, ttl * 1000)
       {:ok, data}
-
+    else
       _ ->
         {:ok, data}
     end
   end
 
-  def set_ttl_based_on_image(data, _url), do: data
+  defp get_ttl_from_image(data, url) do
+    Pleroma.Config.get([:rich_media, :ttl_setters])
+    |> Enum.reduce({:ok, nil}, fn
+      module, {:ok, _ttl} ->
+        module.ttl(data, url)
+
+      _, error ->
+        error
+    end)
+  end
 
   defp parse_url(url) do
     try do

lib/pleroma/web/rich_media/parsers/ttl/aws_signed_url.ex

@@ -1,5 +1,8 @@
 defmodule Pleroma.Web.RichMedia.Parser.TTL.AwsSignedUrl do
-  def run(data, url) do
+  @behaviour Pleroma.Web.RichMedia.Parser.TTL
+
+  @impl Pleroma.Web.RichMedia.Parser.TTL
+  def ttl(data, _url) do
     image = Map.get(data, :image)
 
     if is_aws_signed_url(image) do
@@ -7,7 +10,6 @@ defmodule Pleroma.Web.RichMedia.Parser.TTL.AwsSignedUrl do
       |> parse_query_params()
       |> format_query_params()
       |> get_expiration_timestamp()
-      |> set_ttl(url)
     end
   end
 
@@ -47,8 +49,4 @@ defmodule Pleroma.Web.RichMedia.Parser.TTL.AwsSignedUrl do
 
     Timex.to_unix(date) + String.to_integer(Map.get(params, "X-Amz-Expires"))
   end
-
-  defp set_ttl(ttl, url) do
-    Cachex.expire_at(:rich_media_cache, url, ttl * 1000)
-  end
 end

lib/pleroma/web/rich_media/parsers/ttl/ttl.ex

@@ -0,0 +1,3 @@
+defmodule Pleroma.Web.RichMedia.Parser.TTL do
+  @callback ttl(Map.t(), String.t()) :: {:ok, Integer.t()} | {:error, String.t()}
+end

test/web/rich_media/aws_signed_url_test.exs

@@ -5,7 +5,7 @@
 defmodule Pleroma.Web.RichMedia.TTL.AwsSignedUrlTest do
   use ExUnit.Case, async: true
 
-  test "amazon signed url is parsed and correct ttl is set for rich media" do
+  test "s3 signed url is parsed correct for expiration time" do
     url = "https://pleroma.social/amz"
 
     {:ok, timestamp} =
@@ -16,22 +16,66 @@ defmodule Pleroma.Web.RichMedia.TTL.AwsSignedUrlTest do
     # in seconds
     valid_till = 30
 
-    data = %{
-      image:
-        "https://pleroma.s3.ap-southeast-1.amazonaws.com/sachin%20%281%29%20_a%20-%25%2Aasdasd%20BNN%20bnnn%20.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIBLWWK6RGDQXDLJQ%2F20190716%2Fap-southeast-1%2Fs3%2Faws4_request&X-Amz-Date=#{
-          timestamp
-        }&X-Amz-Expires=#{valid_till}&X-Amz-Signature=04ffd6b98634f4b1bbabc62e0fac4879093cd54a6eed24fe8eb38e8369526bbf&X-Amz-SignedHeaders=host",
-      locale: "en_US",
-      site_name: "Pleroma",
-      title: "PLeroma",
-      url: url
-    }
+    metadata = construct_metadata(timestamp, valid_till, url)
+
+    expire_time =
+      Timex.parse!(timestamp, "{ISO:Basic:Z}") |> Timex.to_unix() |> Kernel.+(valid_till)
+
+    assert expire_time == Pleroma.Web.RichMedia.Parser.TTL.AwsSignedUrl.ttl(metadata, url)
+  end
+
+  test "s3 signed url is parsed and correct ttl is set for rich media" do
+    url = "https://pleroma.social/amz"
+
+    {:ok, timestamp} =
+      Timex.now()
+      |> DateTime.truncate(:second)
+      |> Timex.format("{ISO:Basic:Z}")
+
+    # in seconds
+    valid_till = 30
+
+    metadata = construct_metadata(timestamp, valid_till, url)
+
+    body = """
+    <meta name="twitter:card" content="Pleroma" />
+    <meta name="twitter:site" content="Pleroma" />
+    <meta name="twitter:title" content="Pleroma" />
+    <meta name="twitter:description" content="Pleroma" />
+    <meta name="twitter:image" content="#{Map.get(metadata, :image)}" />
+    """
+
+    Tesla.Mock.mock(fn
+      %{
+        method: :get,
+        url: "https://pleroma.social/amz"
+      } ->
+        %Tesla.Env{status: 200, body: body}
+    end)
+
+    Cachex.put(:rich_media_cache, url, metadata)
+
+    Pleroma.Web.RichMedia.Parser.set_ttl_based_on_image({:ok, metadata}, url)
 
-    Cachex.put(:rich_media_cache, url, data)
-    assert {:ok, _} = Pleroma.Web.RichMedia.Parser.TTL.AwsSignedUrl.run(data, url)
     {:ok, cache_ttl} = Cachex.ttl(:rich_media_cache, url)
 
     # as there is delay in setting and pulling the data from cache we ignore 1 second
     assert_in_delta(valid_till * 1000, cache_ttl, 1000)
   end
+
+  defp construct_s3_url(timestamp, valid_till) do
+    "https://pleroma.s3.ap-southeast-1.amazonaws.com/sachin%20%281%29%20_a%20-%25%2Aasdasd%20BNN%20bnnn%20.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIBLWWK6RGDQXDLJQ%2F20190716%2Fap-southeast-1%2Fs3%2Faws4_request&X-Amz-Date=#{
+      timestamp
+    }&X-Amz-Expires=#{valid_till}&X-Amz-Signature=04ffd6b98634f4b1bbabc62e0fac4879093cd54a6eed24fe8eb38e8369526bbf&X-Amz-SignedHeaders=host"
+  end
+
+  defp construct_metadata(timestamp, valid_till, url) do
+    %{
+      image: construct_s3_url(timestamp, valid_till),
+      site: "Pleroma",
+      title: "Pleroma",
+      description: "Pleroma",
+      url: url
+    }
+  end
 end