# Pleroma: A lightweight social networking server
# Copyright © 2017-2021 Pleroma Authors
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Upload do
@moduledoc """
Manage user uploads
Options:
* `:type`: presets for activity type (defaults to Document) and size limits from app configuration
* `:description`: upload alternative text
* `:base_url`: override base url
* `:uploader`: override uploader
* `:filters`: override filters
* `:size_limit`: override size limit
* `:activity_type`: override activity type
The `%Pleroma.Upload{}` struct: all documented fields are meant to be overwritten in filters:
* `:id` - the upload id.
* `:name` - the upload file name.
* `:path` - the upload path: set at first to `id/name` but can be changed. Keep in mind that the path
is once created permanent and changing it (especially in uploaders) is probably a bad idea!
* `:tempfile` - path to the temporary file. Prefer in-place changes on the file rather than changing the
path as the temporary file is also tracked by `Plug.Upload{}` and automatically deleted once the request is over.
* `:width` - width of the media in pixels
* `:height` - height of the media in pixels
* `:blurhash` - string hash of the image encoded with the blurhash algorithm (https://blurha.sh/)
Related behaviors:
* `Pleroma.Uploaders.Uploader`
* `Pleroma.Upload.Filter`
"""
alias Ecto.UUID
alias Pleroma.Config
alias Pleroma.Maps
alias Pleroma.Web.ActivityPub.Utils
require Logger
@type source ::
Plug.Upload.t()
| (data_uri_string :: String.t())
| {:from_local, name :: String.t(), id :: String.t(), path :: String.t()}
| map()
@type option ::
{:type, :avatar | :banner | :background}
| {:description, String.t()}
| {:activity_type, String.t()}
| {:size_limit, nil | non_neg_integer()}
| {:uploader, module()}
| {:filters, [module()]}
@type t :: %__MODULE__{
id: String.t(),
name: String.t(),
tempfile: String.t(),
content_type: String.t(),
width: integer(),
height: integer(),
blurhash: String.t(),
description: String.t(),
path: String.t()
}
defstruct [
:id,
:name,
:tempfile,
:content_type,
:width,
:height,
:blurhash,
:description,
:path
]
defp get_description(upload) do
case {upload.description, Pleroma.Config.get([Pleroma.Upload, :default_description])} do
{description, _} when is_binary(description) -> description
{_, :filename} -> upload.name
{_, str} when is_binary(str) -> str
_ -> ""
end
end
@spec store(source, options :: [option()]) :: {:ok, Map.t()} | {:error, any()}
@doc "Store a file. If using a `Plug.Upload{}` as the source, be sure to use `Majic.Plug` to ensure its content_type and filename is correct."
def store(upload, opts \\ []) do
opts = get_opts(opts)
with {:ok, upload} <- prepare_upload(upload, opts),
upload = %__MODULE__{upload | path: upload.path || "#{upload.id}/#{upload.name}"},
{:ok, upload} <- Pleroma.Upload.Filter.filter(opts.filters, upload),
description = get_description(upload),
{_, true} <-
{:description_limit,
String.length(description) <= Pleroma.Config.get([:instance, :description_limit])},
{:ok, url_spec} <- Pleroma.Uploaders.Uploader.put_file(opts.uploader, upload) do
{:ok,
%{
"id" => Utils.generate_object_id(),
"type" => opts.activity_type,
"mediaType" => upload.content_type,
"url" => [
%{
"type" => "Link",
"mediaType" => upload.content_type,
"href" => url_from_spec(upload, opts.base_url, url_spec)
}
|> Maps.put_if_present("width", upload.width)
|> Maps.put_if_present("height", upload.height)
],
"name" => description
}
|> Maps.put_if_present("blurhash", upload.blurhash)}
else
{:description_limit, _} ->
{:error, :description_too_long}
{:error, error} ->
Logger.error(
"#{__MODULE__} store (using #{inspect(opts.uploader)}) failed: #{inspect(error)}"
)
{:error, error}
end
end
def char_unescaped?(char) do
URI.char_unreserved?(char) or char == ?/
end
defp get_opts(opts) do
{size_limit, activity_type} =
case Keyword.get(opts, :type) do
:banner ->
{Pleroma.Config.get!([:instance, :banner_upload_limit]), "Image"}
:avatar ->
{Pleroma.Config.get!([:instance, :avatar_upload_limit]), "Image"}
:background ->
{Pleroma.Config.get!([:instance, :background_upload_limit]), "Image"}
_ ->
{Pleroma.Config.get!([:instance, :upload_limit]), "Document"}
end
%{
activity_type: Keyword.get(opts, :activity_type, activity_type),
size_limit: Keyword.get(opts, :size_limit, size_limit),
uploader: Keyword.get(opts, :uploader, Pleroma.Config.get([__MODULE__, :uploader])),
filters: Keyword.get(opts, :filters, Pleroma.Config.get([__MODULE__, :filters])),
description: Keyword.get(opts, :description),
base_url: base_url()
}
end
defp prepare_upload(%Plug.Upload{} = file, opts) do
with :ok <- check_file_size(file.path, opts.size_limit) do
{:ok,
%__MODULE__{
id: UUID.generate(),
name: file.filename,
tempfile: file.path,
content_type: file.content_type,
description: opts.description
}}
end
end
defp prepare_upload(%{img: "data:image/" <> image_data}, opts) do
parsed = Regex.named_captures(~r/(?jpeg|png|gif);base64,(?.*)/, image_data)
data = Base.decode64!(parsed["data"], ignore: :whitespace)
hash = Base.encode16(:crypto.hash(:sha256, data), lower: true)
with :ok <- check_binary_size(data, opts.size_limit),
tmp_path <- tempfile_for_image(data),
{:ok, %{mime_type: content_type}} <-
Majic.perform({:bytes, data}, pool: Pleroma.MajicPool),
[ext | _] <- MIME.extensions(content_type) do
{:ok,
%__MODULE__{
id: UUID.generate(),
name: hash <> "." <> ext,
tempfile: tmp_path,
content_type: content_type,
description: opts.description
}}
end
end
# For Mix.Tasks.MigrateLocalUploads
defp prepare_upload(%__MODULE__{tempfile: path} = upload, _opts) do
with {:ok, %{mime_type: content_type}} <- Majic.perform(path, pool: Pleroma.MajicPool) do
{:ok, %__MODULE__{upload | content_type: content_type}}
end
end
defp check_binary_size(binary, size_limit)
when is_integer(size_limit) and size_limit > 0 and byte_size(binary) >= size_limit do
{:error, :file_too_large}
end
defp check_binary_size(_, _), do: :ok
defp check_file_size(path, size_limit) when is_integer(size_limit) and size_limit > 0 do
with {:ok, %{size: size}} <- File.stat(path),
true <- size <= size_limit do
:ok
else
false -> {:error, :file_too_large}
error -> error
end
end
defp check_file_size(_, _), do: :ok
# Creates a tempfile using the Plug.Upload Genserver which cleans them up
# automatically.
defp tempfile_for_image(data) do
{:ok, tmp_path} = Plug.Upload.random_file("profile_pics")
{:ok, tmp_file} = File.open(tmp_path, [:write, :raw, :binary])
IO.binwrite(tmp_file, data)
tmp_path
end
defp url_from_spec(%__MODULE__{name: name}, base_url, {:file, path}) do
path =
URI.encode(path, &char_unescaped?/1) <>
if Pleroma.Config.get([__MODULE__, :link_name], false) do
"?name=#{URI.encode(name, &char_unescaped?/1)}"
else
""
end
[base_url, path]
|> Path.join()
end
defp url_from_spec(_upload, _base_url, {:url, url}), do: url
def base_url do
uploader = Config.get([Pleroma.Upload, :uploader])
upload_base_url = Config.get([Pleroma.Upload, :base_url])
public_endpoint = Config.get([uploader, :public_endpoint])
case uploader do
Pleroma.Uploaders.Local ->
upload_base_url || Pleroma.Web.Endpoint.url() <> "/media/"
Pleroma.Uploaders.S3 ->
bucket = Config.get([Pleroma.Uploaders.S3, :bucket])
truncated_namespace = Config.get([Pleroma.Uploaders.S3, :truncated_namespace])
namespace = Config.get([Pleroma.Uploaders.S3, :bucket_namespace])
bucket_with_namespace =
cond do
!is_nil(truncated_namespace) ->
truncated_namespace
!is_nil(namespace) ->
namespace <> ":" <> bucket
true ->
bucket
end
if public_endpoint do
Path.join([public_endpoint, bucket_with_namespace])
else
Path.join([upload_base_url, bucket_with_namespace])
end
_ ->
public_endpoint || upload_base_url || Pleroma.Web.Endpoint.url() <> "/media/"
end
end
end