Add specs for the new StaticAssetsHandler

spec/http_server/handlers/static_assets_handler/test.txt

@@ -0,0 +1 @@
+Hello world

spec/http_server/handlers/static_assets_handler_spec.cr

@@ -0,0 +1,205 @@
+{% skip_file if compare_versions(Crystal::VERSION, "1.17.0-dev") < 0 %}
+
+require "http"
+require "spectator"
+require "../../../src/invidious/http_server/static_assets_handler.cr"
+
+private def get_static_assets_handler
+  return Invidious::HttpServer::StaticAssetsHandler.new "spec/http_server/handlers/static_assets_handler", directory_listing: false
+end
+
+# Slightly modified version of `handle` function from
+#
+# https://github.com/crystal-lang/crystal/blob/3f369d2c721e9462d9f6126cb0bcd4c6992f0225/spec/std/http/server/handlers/static_file_handler_spec.cr#L5
+
+private def handle(request, handler : HTTP::Handler? = nil, decompress : Bool = false)
+  io = IO::Memory.new
+  response = HTTP::Server::Response.new(io)
+  context = HTTP::Server::Context.new(request, response)
+
+  if !handler
+    handler = get_static_assets_handler
+    get_static_assets_handler.call context
+  else
+    handler.call(context)
+  end
+
+  response.close
+  io.rewind
+
+  HTTP::Client::Response.from_io(io, decompress: decompress)
+end
+
+# Makes and yields a temporary file with the given prefix
+private def make_temporary_file(prefix, contents = nil, &)
+  tempfile = File.tempfile(prefix, "static_assets_handler_spec", dir: "spec/http_server/handlers/static_assets_handler")
+  yield tempfile
+ensure
+  tempfile.try &.delete
+end
+
+# Get relative file path to a file within the static_assets_handler folder
+macro get_file_path(basename)
+  "spec/http_server/handlers/static_assets_handler/#{ {{basename}} }"
+end
+
+Spectator.describe StaticAssetsHandler do
+  it "Can serve a file" do
+    response = handle HTTP::Request.new("GET", "/test.txt")
+    expect(response.status_code).to eq(200)
+    expect(response.body).to eq(File.read(get_file_path("test.txt")))
+  end
+
+  it "Can serve cached file" do
+    make_temporary_file("cache_test") do |temporary_file|
+      temporary_file.rewind << "foo"
+      temporary_file.flush
+      expect(temporary_file.rewind.gets_to_end).to eq("foo")
+
+      file_link = "/#{File.basename(temporary_file.path)}"
+
+      # Should get cached by the first run
+      response = handle HTTP::Request.new("GET", file_link)
+      expect(response.status_code).to eq(200)
+      expect(response.body).to eq("foo")
+
+      # Update temporary file to "bar"
+      temporary_file.rewind << "bar"
+      temporary_file.flush
+      expect(temporary_file.rewind.gets_to_end).to eq("bar")
+
+      # Second request should still return "foo"
+      response = handle HTTP::Request.new("GET", file_link)
+      expect(response.status_code).to eq(200)
+      expect(response.body).to eq("foo")
+    end
+  end
+
+  it "Adds cache headers" do
+    response = handle HTTP::Request.new("GET", "/test.txt")
+    expect(response.headers["cache_control"]).to eq("max-age=2629800")
+  end
+
+  context "Can handle range requests" do
+    it "Can serve range request" do
+      headers = HTTP::Headers{"Range" => "bytes=0-2"}
+      response = handle HTTP::Request.new("GET", "/test.txt", headers)
+
+      expect(response.status_code).to eq(206)
+      expect(response.headers["Content-Range"]?).to eq "bytes 0-2/11"
+      expect(response.body).to eq "Hel"
+    end
+
+    it "Will cache entire file even if doing partial requests" do
+      make_temporary_file("range_cache") do |temporary_file|
+        temporary_file << "Hello world"
+        temporary_file.flush.rewind
+        file_link = "/#{File.basename(temporary_file.path)}"
+
+        # Make request
+        headers = HTTP::Headers{"Range" => "bytes=0-2"}
+        response = handle HTTP::Request.new("GET", file_link, headers)
+
+        # Mutate file on disk
+        temporary_file << "Something else"
+        temporary_file.flush.rewind
+
+        # Second request shouldn't have changed
+        headers = HTTP::Headers{"Range" => "bytes=3-8"}
+        response = handle HTTP::Request.new("GET", file_link, headers)
+        expect(response.status_code).to eq(206)
+        expect(response.body).to eq "lo wor"
+      end
+    end
+  end
+
+  context "Is able to support compression" do
+    def decompressed(string : String)
+      decompressed = Compress::Gzip::Reader.open(IO::Memory.new(string)) do |gzip|
+        gzip.gets_to_end
+      end
+
+      return expect(decompressed)
+    end
+
+    it "For full file requests" do
+      handler = HTTP::CompressHandler.new
+      handler.next = get_static_assets_handler()
+
+      make_temporary_file("check decompression handler") do |temporary_file|
+        temporary_file << "Hello world"
+        temporary_file.flush.rewind
+        file_link = "/#{File.basename(temporary_file.path)}"
+
+        # Can send from disk?
+        response = handle HTTP::Request.new("GET", file_link, headers: HTTP::Headers{"Accept-Encoding" => "gzip"}), handler: handler
+        expect(response.headers["Content-Encoding"]).to eq("gzip")
+        decompressed(response.body).to eq("Hello world")
+
+        temporary_file << "Hello world"
+        temporary_file.flush.rewind
+        file_link = "/#{File.basename(temporary_file.path)}"
+
+        # Are cached requests working?
+        response = handle HTTP::Request.new("GET", file_link, headers: HTTP::Headers{"Accept-Encoding" => "gzip"}), handler: handler
+        expect(response.headers["Content-Encoding"]).to eq("gzip")
+        decompressed(response.body).to eq("Hello world")
+
+        # Able to retrieve non gzipped file?
+        response = handle HTTP::Request.new("GET", file_link), handler: handler
+        expect(response.body).to eq("Hello world")
+        expect(response.headers).to_not have_key("Content-Encoding")
+      end
+    end
+
+    # Inspired by the equivalent tests from upstream
+    it "For partial file requests" do
+      handler = HTTP::CompressHandler.new
+      handler.next = get_static_assets_handler()
+
+      make_temporary_file("check_decompression_handler_on_partial_requests") do |temporary_file|
+        temporary_file << "Hello world this is a very long string"
+        temporary_file.flush.rewind
+        file_link = "/#{File.basename(temporary_file.path)}"
+
+        range_response_results = {
+          "10-20/38" => "d this is a",
+          "0-0/38"   => "H",
+          "5-9/38"   => " worl",
+        }
+
+        range_request_header_value = {"10-20", "5-9", "0-0"}.join(',')
+        range_response_header_value = range_response_results.keys
+
+        response = handle HTTP::Request.new("GET", file_link, headers: HTTP::Headers{"Range" => "bytes=#{range_request_header_value}", "Accept-Encoding" => "gzip"}), handler: handler
+        expect(response.headers["Content-Encoding"]).to eq("gzip")
+
+        # Decompress response
+        response = HTTP::Client::Response.new(
+          status: response.status,
+          headers: response.headers,
+          body_io: Compress::Gzip::Reader.new(IO::Memory.new(response.body)),
+        )
+
+        count = 0
+        MIME::Multipart.parse(response) do |headers, part|
+          part_range = headers["Content-Range"][6..]
+          expect(part_range).to be_within(range_response_header_value)
+          expect(part.gets_to_end).to eq(range_response_results[part_range])
+          count += 1
+        end
+
+        expect(count).to eq(3)
+
+        # Is the file cached?
+        temporary_file << "Something else"
+        temporary_file.flush.rewind
+
+        response = handle HTTP::Request.new("GET", file_link, headers: HTTP::Headers{"Accept-Encoding" => "gzip"}), handler: handler
+        decompressed(response.body).to eq("Hello world this is a very long string")
+      end
+    end
+  end
+
+  after_each { Invidious::HttpServer::StaticAssetsHandler.clear_cache }
+end

src/invidious/http_server/static_assets_handler.cr

@@ -107,5 +107,12 @@ module Invidious::HttpServer
       # Paste in the body of inherited serve_file_range
       {{@type.superclass.methods.select(&.name.==("serve_file_range"))[0].body}}
     end
+
+    # Clear cached files.
+    #
+    # This is only used in the specs to clear the cache before each handler test
+    def self.clear_cache
+      return @@cached_files.clear
+    end
   end
 end