livebook/lib/livebook_web/plugs/memory_provider.ex
2023-09-21 12:28:45 +02:00

72 lines
2.4 KiB
Elixir

defmodule LivebookWeb.MemoryProvider do
@gzippable_exts ~w(.js .css .txt .text .html .json .svg .eot .ttf)
# Configurable implementation of `LivebookWeb.StaticPlug.Provider` behaviour,
# that bundles the files into the module compiled source.
#
# ## `use` options
#
# * `:from` (**required**) - where to read the static files from. See `Plug.Static` for more details.
#
# * `:gzip` - whether to bundle gzipped version of the files,
# in which case the uncompressed files are not included. Defaults to `false`.
defmacro __using__(opts) do
quote bind_quoted: [opts: opts] do
@behaviour LivebookWeb.StaticPlug.Provider
from = Keyword.fetch!(opts, :from)
static_path = LivebookWeb.StaticPlug.Provider.static_path(from)
paths = LivebookWeb.MemoryProvider.__paths__(static_path)
files = LivebookWeb.MemoryProvider.__preload_files__!(static_path, paths, opts)
for path <- paths do
abs_path = Path.join(static_path, path)
@external_resource Path.relative_to_cwd(abs_path)
end
@impl true
def get_file(segments, compression)
for {segments, compression, file} <- files do
def get_file(unquote(segments), unquote(compression)), do: unquote(Macro.escape(file))
end
def get_file(_, _), do: nil
# Force recompilation if the static files change.
def __mix_recompile__? do
current_paths = LivebookWeb.MemoryProvider.__paths__(unquote(static_path))
:erlang.md5(current_paths) != unquote(:erlang.md5(paths))
end
end
end
def __preload_files__!(static_path, paths, opts) do
gzip? = Keyword.get(opts, :gzip, false)
Enum.map(paths, fn path ->
segments = Path.split(path)
abs_path = Path.join(static_path, path)
content = File.read!(abs_path)
digest = content |> :erlang.md5() |> Base.encode16(case: :lower)
if gzip? and Path.extname(path) in @gzippable_exts do
gzipped_content = :zlib.gzip(content)
{segments, :gzip, %LivebookWeb.StaticPlug.File{content: gzipped_content, digest: digest}}
else
{segments, nil, %LivebookWeb.StaticPlug.File{content: content, digest: digest}}
end
end)
end
def __paths__(static_path) do
Path.join(static_path, "**")
|> Path.wildcard()
|> Enum.reject(&File.dir?/1)
|> Enum.map(&String.replace_leading(&1, static_path <> "/", ""))
|> Enum.sort()
end
end