RichMedia refactor

Rich Media parsing was previously handled on-demand with a 2 second HTTP request timeout and retained only in Cachex. Every time a Pleroma instance is restarted it will have to request and parse the data for each status with a URL detected. When fetching a batch of statuses they were processed in parallel to attempt to keep the maximum latency at 2 seconds, but often resulted in a timeline appearing to hang during loading due to a URL that could not be successfully reached. URLs which had images links that expire (Amazon AWS) were parsed and inserted with a TTL to ensure the image link would not break.

Rich Media data is now cached in the database and fetched asynchronously. Cachex is used as a read-through cache. When the data becomes available we stream an update to the clients. If the result is returned quickly the experience is almost seamless. Activities were already processed for their Rich Media data during ingestion to warm the cache, so users should not normally encounter the asynchronous loading of the Rich Media data.

Implementation notes:

- The async worker is a Task with a globally unique process name to prevent duplicate processing of the same URL
- The Task will attempt to fetch the data 3 times with increasing sleep time between attempts
- The HTTP request obeys the default HTTP request timeout value instead of 2 seconds
- URLs that cannot be successfully parsed due to an unexpected error receives a negative cache entry for 15 minutes
- URLs that fail with an expected error will receive a negative cache with no TTL
- Activities that have no detected URLs insert a nil value in the Cachex :scrubber_cache so we do not repeat parsing the object content with Floki every time the activity is rendered
- Expiring image URLs are handled with an Oban job
- There is no automatic cleanup of the Rich Media data in the database, but it is safe to delete at any time
- The post draft/preview feature makes the URL processing synchronous so the rendered post preview will have an accurate rendering

Overall performance of timelines and creating new posts which contain URLs is greatly improved.
This commit is contained in:
Mark Felder 2024-02-11 16:11:52 -05:00
parent b42963a52c
commit ede414094f
17 changed files with 355 additions and 212 deletions

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@ -0,0 +1 @@
Refactored Rich Media to cache the content in the database. Fetching operations that could block status rendering have been eliminated.

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@ -575,7 +575,8 @@
attachments_cleanup: 1,
new_users_digest: 1,
mute_expire: 5,
search_indexing: 10
search_indexing: 10,
rich_media_expiration: 2
],
plugins: [Oban.Plugins.Pruner],
crontab: [

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@ -174,6 +174,8 @@
config :pleroma, Pleroma.Emoji.Loader, test_emoji: true
config :pleroma, Pleroma.Web.RichMedia.Backfill, provider: Pleroma.Web.RichMedia.Backfill
if File.exists?("./config/test.secret.exs") do
import_config "test.secret.exs"
else

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@ -65,20 +65,16 @@ def ensure_scrubbed_html(
end
end
@spec extract_first_external_url_from_object(Pleroma.Object.t()) ::
{:ok, String.t()} | {:error, :no_content}
@spec extract_first_external_url_from_object(Pleroma.Object.t()) :: String.t() | nil
def extract_first_external_url_from_object(%{data: %{"content" => content}})
when is_binary(content) do
url =
content
|> Floki.parse_fragment!()
|> Floki.find("a:not(.mention,.hashtag,.attachment,[rel~=\"tag\"])")
|> Enum.take(1)
|> Floki.attribute("href")
|> Enum.at(0)
{:ok, url}
content
|> Floki.parse_fragment!()
|> Floki.find("a:not(.mention,.hashtag,.attachment,[rel~=\"tag\"])")
|> Enum.take(1)
|> Floki.attribute("href")
|> Enum.at(0)
end
def extract_first_external_url_from_object(_), do: {:error, :no_content}
def extract_first_external_url_from_object(_), do: nil
end

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@ -147,9 +147,7 @@ def insert(map, local \\ true, fake \\ false, bypass_actor_check \\ false) when
# Splice in the child object if we have one.
activity = Maps.put_if_present(activity, :object, object)
ConcurrentLimiter.limit(Pleroma.Web.RichMedia.Helpers, fn ->
Task.start(fn -> Pleroma.Web.RichMedia.Helpers.fetch_data_for_activity(activity) end)
end)
Pleroma.Web.RichMedia.Card.get_by_activity(activity)
# Add local posts to search index
if local, do: Pleroma.Search.add_to_index(activity)
@ -177,7 +175,7 @@ def insert(map, local \\ true, fake \\ false, bypass_actor_check \\ false) when
id: "pleroma:fakeid"
}
Pleroma.Web.RichMedia.Helpers.fetch_data_for_activity(activity)
Pleroma.Web.RichMedia.Card.get_by_activity(activity)
{:ok, activity}
{:remote_limit_pass, _} ->

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@ -227,9 +227,7 @@ def handle(%{data: %{"type" => "Create"}} = activity, meta) do
end
end
ConcurrentLimiter.limit(Pleroma.Web.RichMedia.Helpers, fn ->
Task.start(fn -> Pleroma.Web.RichMedia.Helpers.fetch_data_for_activity(activity) end)
end)
Pleroma.Web.RichMedia.Card.get_by_activity(activity)
Pleroma.Search.add_to_index(Map.put(activity, :object, object))

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@ -25,6 +25,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusController do
alias Pleroma.Web.OAuth.Token
alias Pleroma.Web.Plugs.OAuthScopesPlug
alias Pleroma.Web.Plugs.RateLimiter
alias Pleroma.Web.RichMedia.Card
plug(Pleroma.Web.ApiSpec.CastAndValidate, replace_params: false)
@ -480,9 +481,9 @@ def card(
_
) do
with %Activity{} = activity <- Activity.get_by_id(status_id),
true <- Visibility.visible_for_user?(activity, user) do
data = Pleroma.Web.RichMedia.Helpers.fetch_data_for_activity(activity)
render(conn, "card.json", data)
true <- Visibility.visible_for_user?(activity, user),
%Card{} = card_data <- Card.get_by_activity(activity) do
render(conn, "card.json", card_data)
else
_ -> render_error(conn, :not_found, "Record not found")
end

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@ -21,6 +21,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
alias Pleroma.Web.MastodonAPI.StatusView
alias Pleroma.Web.MediaProxy
alias Pleroma.Web.PleromaAPI.EmojiReactionController
alias Pleroma.Web.RichMedia.Card
import Pleroma.Web.ActivityPub.Visibility, only: [get_visibility: 1, visible_for_user?: 2]
@ -29,9 +30,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
# pagination is restricted to 40 activities at a time
defp fetch_rich_media_for_activities(activities) do
Enum.each(activities, fn activity ->
spawn(fn ->
Pleroma.Web.RichMedia.Helpers.fetch_data_for_activity(activity)
end)
spawn(fn -> Card.get_by_activity(activity) end)
end)
end
@ -113,9 +112,7 @@ def render("index.json", opts) do
# To do: check AdminAPIControllerTest on the reasons behind nil activities in the list
activities = Enum.filter(opts.activities, & &1)
# Start fetching rich media before doing anything else, so that later calls to get the cards
# only block for timeout in the worst case, as opposed to
# length(activities_with_links) * timeout
# Start prefetching rich media before doing anything else
fetch_rich_media_for_activities(activities)
replied_to_activities = get_replied_to_activities(activities)
quoted_activities = get_quoted_activities(activities)
@ -364,7 +361,11 @@ def render("show.json", %{activity: %{data: %{"object" => _object}} = activity}
summary = object.data["summary"] || ""
card = render("card.json", Pleroma.Web.RichMedia.Helpers.fetch_data_for_activity(activity))
card =
case Card.get_by_activity(activity) do
%Card{} = result -> render("card.json", result)
_ -> nil
end
url =
if user.local do
@ -567,15 +568,8 @@ def render("source.json", %{activity: %{data: %{"object" => _object}} = activity
}
end
def render("card.json", %{rich_media: rich_media, page_url: page_url}) do
page_url_data = URI.parse(page_url)
page_url_data =
if is_binary(rich_media["url"]) do
URI.merge(page_url_data, URI.parse(rich_media["url"]))
else
page_url_data
end
def render("card.json", %Card{fields: rich_media}) do
page_url_data = URI.parse(rich_media["url"])
page_url = page_url_data |> to_string

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@ -9,6 +9,7 @@ defmodule Pleroma.Web.PleromaAPI.Chat.MessageReferenceView do
alias Pleroma.User
alias Pleroma.Web.CommonAPI.Utils
alias Pleroma.Web.MastodonAPI.StatusView
alias Pleroma.Web.RichMedia.Card
@cachex Pleroma.Config.get([:cachex, :provider], Cachex)
@ -23,6 +24,12 @@ def render(
}
}
) do
card =
case Card.get_by_object(object) do
%Card{} = card_data -> StatusView.render("card.json", card_data)
_ -> nil
end
%{
id: id |> to_string(),
content: chat_message["content"],
@ -34,11 +41,7 @@ def render(
chat_message["attachment"] &&
StatusView.render("attachment.json", attachment: chat_message["attachment"]),
unread: unread,
card:
StatusView.render(
"card.json",
Pleroma.Web.RichMedia.Helpers.fetch_data_for_object(object)
)
card: card
}
|> put_idempotency_key()
end

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@ -0,0 +1,101 @@
# Pleroma: A lightweight social networking server
# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Web.RichMedia.Backfill.Task do
alias Pleroma.Web.RichMedia.Backfill
def run(args) do
Task.Supervisor.start_child(Pleroma.TaskSupervisor, Backfill, :run, [args],
name: {:global, {:rich_media, args.url_hash}}
)
end
end
defmodule Pleroma.Web.RichMedia.Backfill do
alias Pleroma.Web.RichMedia.Card
alias Pleroma.Web.RichMedia.Parser
alias Pleroma.Web.RichMedia.Parser.TTL
alias Pleroma.Workers.RichMediaExpirationWorker
require Logger
@backfiller Pleroma.Config.get([__MODULE__, :provider], Pleroma.Web.RichMedia.Backfill.Task)
@cachex Pleroma.Config.get([:cachex, :provider], Cachex)
@max_attempts 3
@retry 5_000
def start(%{url: url} = args) when is_binary(url) do
url_hash = Card.url_to_hash(url)
args =
args
|> Map.put(:attempt, 1)
|> Map.put(:url_hash, url_hash)
@backfiller.run(args)
end
def run(%{url: url, url_hash: url_hash, attempt: attempt} = args)
when attempt <= @max_attempts do
case Parser.parse(url) do
{:ok, fields} ->
{:ok, card} = Card.create(url, fields)
maybe_schedule_expiration(url, fields)
if Map.has_key?(args, :activity_id) do
stream_update(args)
end
warm_cache(url_hash, card)
{:error, {:invalid_metadata, fields}} ->
Logger.debug("Rich media incomplete or invalid metadata for #{url}: #{inspect(fields)}")
negative_cache(url_hash)
{:error, :body_too_large} ->
Logger.error("Rich media error for #{url}: :body_too_large")
negative_cache(url_hash)
{:error, {:content_type, type}} ->
Logger.debug("Rich media error for #{url}: :content_type is #{type}")
negative_cache(url_hash)
e ->
Logger.debug("Rich media error for #{url}: #{inspect(e)}")
:timer.sleep(@retry * attempt)
run(%{args | attempt: attempt + 1})
end
end
def run(%{url: url, url_hash: url_hash}) do
Logger.debug("Rich media failure for #{url}")
negative_cache(url_hash, :timer.minutes(15))
end
defp maybe_schedule_expiration(url, fields) do
case TTL.get_from_image(fields, url) do
ttl when is_number(ttl) ->
timestamp = DateTime.from_unix!(ttl)
RichMediaExpirationWorker.new(%{"url" => url}, scheduled_at: timestamp)
|> Oban.insert()
_ ->
:ok
end
end
defp stream_update(%{activity_id: activity_id}) do
Pleroma.Activity.get_by_id(activity_id)
|> Pleroma.Activity.normalize()
|> Pleroma.Web.ActivityPub.ActivityPub.stream_out()
end
defp warm_cache(key, val), do: @cachex.put(:rich_media_cache, key, val)
defp negative_cache(key, ttl \\ nil), do: @cachex.put(:rich_media_cache, key, nil, ttl: ttl)
end

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@ -0,0 +1,157 @@
defmodule Pleroma.Web.RichMedia.Card do
use Ecto.Schema
import Ecto.Changeset
import Ecto.Query
alias Pleroma.Activity
alias Pleroma.HTML
alias Pleroma.Object
alias Pleroma.Repo
alias Pleroma.Web.RichMedia.Backfill
alias Pleroma.Web.RichMedia.Parser
@cachex Pleroma.Config.get([:cachex, :provider], Cachex)
@config_impl Application.compile_env(:pleroma, [__MODULE__, :config_impl], Pleroma.Config)
@type t :: %__MODULE__{}
schema "rich_media_card" do
field(:url_hash, :binary)
field(:fields, :map)
timestamps()
end
@doc false
def changeset(card, attrs) do
card
|> cast(attrs, [:url_hash, :fields])
|> validate_required([:url_hash, :fields])
|> unique_constraint(:url_hash)
end
@spec create(String.t(), map()) :: {:ok, t()}
def create(url, fields) do
url_hash = url_to_hash(url)
fields = Map.put_new(fields, "url", url)
%__MODULE__{}
|> changeset(%{url_hash: url_hash, fields: fields})
|> Repo.insert(on_conflict: {:replace, [:fields]}, conflict_target: :url_hash)
end
@spec delete(String.t()) :: {:ok, Ecto.Schema.t()} | {:error, Ecto.Changeset.t()} | :ok
def delete(url) do
url_hash = url_to_hash(url)
@cachex.del(:rich_media_cache, url_hash)
case get_by_url(url) do
%__MODULE{} = card -> Repo.delete(card)
nil -> :ok
end
end
@spec get_by_url(String.t() | nil) :: t() | nil | :error
def get_by_url(url) when is_binary(url) do
if @config_impl.get([:rich_media, :enabled]) do
url_hash = url_to_hash(url)
@cachex.fetch!(:rich_media_cache, url_hash, fn _ ->
result =
__MODULE__
|> where(url_hash: ^url_hash)
|> Repo.one()
case result do
%__MODULE__{} = card -> {:commit, card}
_ -> {:ignore, nil}
end
end)
else
:error
end
end
def get_by_url(nil), do: nil
@spec get_or_backfill_by_url(String.t(), map()) :: t() | nil
def get_or_backfill_by_url(url, backfill_opts \\ %{}) do
case get_by_url(url) do
%__MODULE__{} = card ->
card
nil ->
backfill_opts = Map.put(backfill_opts, :url, url)
Backfill.start(backfill_opts)
nil
:error ->
nil
end
end
@spec get_by_object(Object.t()) :: t() | nil | :error
def get_by_object(object) do
case HTML.extract_first_external_url_from_object(object) do
nil -> nil
url -> get_or_backfill_by_url(url)
end
end
@spec get_by_activity(Activity.t()) :: t() | nil | :error
# Fake/Draft activity
def get_by_activity(%Activity{id: "pleroma:fakeid"} = activity) do
with %Object{} = object <- Object.normalize(activity, fetch: false),
url when not is_nil(url) <- HTML.extract_first_external_url_from_object(object) do
case get_by_url(url) do
# Cache hit
%__MODULE__{} = card ->
card
# Cache miss, but fetch for rendering the Draft
_ ->
with {:ok, fields} <- Parser.parse(url),
{:ok, card} <- create(url, fields) do
card
else
_ -> nil
end
end
else
_ ->
nil
end
end
def get_by_activity(activity) do
with %Object{} = object <- Object.normalize(activity, fetch: false),
{_, nil} <- {:cached, get_cached_url(object, activity.id)} do
nil
else
{:cached, url} ->
get_or_backfill_by_url(url, %{activity_id: activity.id})
_ ->
:error
end
end
@spec url_to_hash(String.t()) :: String.t()
def url_to_hash(url) do
:crypto.hash(:sha256, url) |> Base.encode16(case: :lower)
end
defp get_cached_url(object, activity_id) do
key = "URL|#{activity_id}"
@cachex.fetch!(:scrubber_cache, key, fn _ ->
url = HTML.extract_first_external_url_from_object(object)
Activity.HTML.add_cache_key_for(activity_id, key)
{:commit, url}
end)
end
end

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@ -3,65 +3,13 @@
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Web.RichMedia.Helpers do
alias Pleroma.Activity
alias Pleroma.HTML
alias Pleroma.Object
alias Pleroma.Web.RichMedia.Parser
@cachex Pleroma.Config.get([:cachex, :provider], Cachex)
@config_impl Application.compile_env(:pleroma, [__MODULE__, :config_impl], Pleroma.Config)
@options [
pool: :media,
max_body: 2_000_000,
recv_timeout: 2_000
]
def fetch_data_for_object(object) do
with true <- @config_impl.get([:rich_media, :enabled]),
{:ok, page_url} <-
HTML.extract_first_external_url_from_object(object),
{:ok, rich_media} <- Parser.parse(page_url) do
%{page_url: page_url, rich_media: rich_media}
else
_ -> %{}
end
end
def fetch_data_for_activity(%Activity{data: %{"type" => "Create"}} = activity) do
with true <- @config_impl.get([:rich_media, :enabled]),
%Object{} = object <- Object.normalize(activity, fetch: false) do
if object.data["fake"] do
fetch_data_for_object(object)
else
key = "URL|#{activity.id}"
@cachex.fetch!(:scrubber_cache, key, fn _ ->
result = fetch_data_for_object(object)
cond do
match?(%{page_url: _, rich_media: _}, result) ->
Activity.HTML.add_cache_key_for(activity.id, key)
{:commit, result}
true ->
{:ignore, %{}}
end
end)
end
else
_ -> %{}
end
end
def fetch_data_for_activity(_), do: %{}
alias Pleroma.Config
def rich_media_get(url) do
headers = [{"user-agent", Pleroma.Application.user_agent() <> "; Bot"}]
head_check =
case Pleroma.HTTP.head(url, headers, @options) do
case Pleroma.HTTP.head(url, headers, http_options()) do
# If the HEAD request didn't reach the server for whatever reason,
# we assume the GET that comes right after won't either
{:error, _} = e ->
@ -76,7 +24,7 @@ def rich_media_get(url) do
:ok
end
with :ok <- head_check, do: Pleroma.HTTP.get(url, headers, @options)
with :ok <- head_check, do: Pleroma.HTTP.get(url, headers, http_options())
end
defp check_content_type(headers) do
@ -92,12 +40,13 @@ defp check_content_type(headers) do
end
end
@max_body @options[:max_body]
defp check_content_length(headers) do
max_body = Keyword.get(http_options(), :max_body)
case List.keyfind(headers, "content-length", 0) do
{_, maybe_content_length} ->
case Integer.parse(maybe_content_length) do
{content_length, ""} when content_length <= @max_body -> :ok
{content_length, ""} when content_length <= max_body -> :ok
{_, ""} -> {:error, :body_too_large}
_ -> :ok
end
@ -106,4 +55,11 @@ defp check_content_length(headers) do
:ok
end
end
defp http_options() do
[
pool: :media,
max_body: Config.get([:rich_media, :max_body], 2_000_000)
]
end
end

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@ -5,134 +5,28 @@
defmodule Pleroma.Web.RichMedia.Parser do
require Logger
@cachex Pleroma.Config.get([:cachex, :provider], Cachex)
@config_impl Application.compile_env(:pleroma, [__MODULE__, :config_impl], Pleroma.Config)
defp parsers do
Pleroma.Config.get([:rich_media, :parsers])
end
def parse(nil), do: {:error, "No URL provided"}
def parse(nil), do: nil
@spec parse(String.t()) :: {:ok, map()} | {:error, any()}
def parse(url) do
with :ok <- validate_page_url(url),
{:ok, data} <- get_cached_or_parse(url),
{:ok, _} <- set_ttl_based_on_image(data, url) do
{:ok, data} <- parse_url(url) do
data = Map.put(data, "url", url)
{:ok, data}
end
end
defp get_cached_or_parse(url) do
case @cachex.fetch(:rich_media_cache, url, fn ->
case parse_url(url) do
{:ok, _} = res ->
{:commit, res}
{:error, reason} = e ->
# Unfortunately we have to log errors here, instead of doing that
# along with ttl setting at the bottom. Otherwise we can get log spam
# if more than one process was waiting for the rich media card
# while it was generated. Ideally we would set ttl here as well,
# so we don't override it number_of_waiters_on_generation
# times, but one, obviously, can't set ttl for not-yet-created entry
# and Cachex doesn't support returning ttl from the fetch callback.
log_error(url, reason)
{:commit, e}
end
end) do
{action, res} when action in [:commit, :ok] ->
case res do
{:ok, _data} = res ->
res
{:error, reason} = e ->
if action == :commit, do: set_error_ttl(url, reason)
e
end
{:error, e} ->
{:error, {:cachex_error, e}}
end
end
defp set_error_ttl(_url, :body_too_large), do: :ok
defp set_error_ttl(_url, {:content_type, _}), do: :ok
# The TTL is not set for the errors above, since they are unlikely to change
# with time
defp set_error_ttl(url, _reason) do
ttl = Pleroma.Config.get([:rich_media, :failure_backoff], 60_000)
@cachex.expire(:rich_media_cache, url, ttl)
:ok
end
defp log_error(url, {:invalid_metadata, data}) do
Logger.debug(fn -> "Incomplete or invalid metadata for #{url}: #{inspect(data)}" end)
end
defp log_error(url, reason) do
Logger.warning(fn -> "Rich media error for #{url}: #{inspect(reason)}" end)
end
@doc """
Set the rich media cache based on the expiration time of image.
Adopt behaviour `Pleroma.Web.RichMedia.Parser.TTL`
## Example
defmodule MyModule 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
# and return ttl is unix time
parse_ttl_from_url(image_url)
end
end
Define the module in the config
config :pleroma, :rich_media,
ttl_setters: [MyModule]
"""
@spec set_ttl_based_on_image(map(), String.t()) ::
{:ok, integer() | :noop} | {:error, :no_key}
def set_ttl_based_on_image(data, url) do
case get_ttl_from_image(data, url) do
ttl when is_number(ttl) ->
ttl = ttl * 1000
case @cachex.expire_at(:rich_media_cache, url, ttl) do
{:ok, true} -> {:ok, ttl}
{:ok, false} -> {:error, :no_key}
end
_ ->
{:ok, :noop}
end
end
defp get_ttl_from_image(data, url) do
[:rich_media, :ttl_setters]
|> Pleroma.Config.get()
|> Enum.reduce({:ok, nil}, fn
module, {:ok, _ttl} ->
module.ttl(data, url)
_, error ->
error
end)
end
def parse_url(url) do
defp parse_url(url) do
with {:ok, %Tesla.Env{body: html}} <- Pleroma.Web.RichMedia.Helpers.rich_media_get(url),
{:ok, html} <- Floki.parse_document(html) do
html
|> maybe_parse()
|> Map.put("url", url)
|> clean_parsed_data()
|> check_parsed_data()
end

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@ -4,4 +4,16 @@
defmodule Pleroma.Web.RichMedia.Parser.TTL do
@callback ttl(map(), String.t()) :: integer() | nil
def get_from_image(data, url) do
[:rich_media, :ttl_setters]
|> Pleroma.Config.get()
|> Enum.reduce({:ok, nil}, fn
module, {:ok, _ttl} ->
module.ttl(data, url)
_, error ->
error
end)
end
end

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@ -7,7 +7,7 @@ defmodule Pleroma.Web.RichMedia.Parser.TTL.AwsSignedUrl do
@impl true
def ttl(data, _url) do
image = Map.get(data, :image)
image = Map.get(data, "image")
if aws_signed_url?(image) do
image

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@ -0,0 +1,15 @@
# Pleroma: A lightweight social networking server
# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Workers.RichMediaExpirationWorker do
alias Pleroma.Web.RichMedia.Card
use Oban.Worker,
queue: :rich_media_expiration
@impl Oban.Worker
def perform(%Job{args: %{"url" => url} = _args}) do
Card.delete(url)
end
end

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@ -0,0 +1,14 @@
defmodule Pleroma.Repo.Migrations.CreateRichMediaCard do
use Ecto.Migration
def change do
create table(:rich_media_card) do
add(:url_hash, :bytea)
add(:fields, :map)
timestamps()
end
create(unique_index(:rich_media_card, [:url_hash]))
end
end