Implement a function to calculate IANA MIME types

Signed-off-by: Juan Cruz Viotti <[email protected]>

src/http/CMakeLists.txt

@@ -1,7 +1,7 @@
 noa_library(NAMESPACE sourcemeta PROJECT hydra NAME http
   FOLDER "Hydra/HTTP"
-  PRIVATE_HEADERS method.h status.h error.h header.h time.h
-  SOURCES method.cc status.cc error.cc header.cc time.cc)
+  PRIVATE_HEADERS method.h status.h error.h header.h time.h mime.h
+  SOURCES method.cc status.cc error.cc header.cc time.cc mime.cc)
 
 if(HYDRA_INSTALL)
   noa_library_install(NAMESPACE sourcemeta PROJECT hydra NAME http)

src/http/include/sourcemeta/hydra/http.h

@@ -14,6 +14,7 @@
 #include <sourcemeta/hydra/http_error.h>
 #include <sourcemeta/hydra/http_header.h>
 #include <sourcemeta/hydra/http_method.h>
+#include <sourcemeta/hydra/http_mime.h>
 #include <sourcemeta/hydra/http_status.h>
 #include <sourcemeta/hydra/http_time.h>
 

src/http/include/sourcemeta/hydra/http_mime.h

@@ -0,0 +1,30 @@
+#ifndef SOURCEMETA_HYDRA_HTTP_MIME_H
+#define SOURCEMETA_HYDRA_HTTP_MIME_H
+
+#if defined(__Unikraft__)
+#define SOURCEMETA_HYDRA_HTTP_EXPORT
+#else
+#include "http_export.h"
+#endif
+
+#include <filesystem> // std::filesystem
+#include <string>     // std::string
+
+namespace sourcemeta::hydra::http {
+
+/// @ingroup http
+/// Find a IANA MIME type for the given file. For example:
+///
+/// ```cpp
+/// #include <sourcemeta/hydra/http.h>
+/// #include <cassert>
+///
+/// const auto result{sourcemeta::hydra::http::mime_type("image.png")};
+/// assert(result == "image/png");
+/// ```
+auto SOURCEMETA_HYDRA_HTTP_EXPORT
+mime_type(const std::filesystem::path &file_path) -> std::string;
+
+} // namespace sourcemeta::hydra::http
+
+#endif

src/http/mime.cc

@@ -0,0 +1,32 @@
+#include <sourcemeta/hydra/http_mime.h>
+
+#include <algorithm> // std::transform
+#include <cctype>    // std::tolower
+#include <map>       // std::map
+
+namespace sourcemeta::hydra::http {
+
+// See https://www.iana.org/assignments/media-types/media-types.xhtml
+auto mime_type(const std::filesystem::path &file_path) -> std::string {
+  // TODO: More exhaustively define all known types
+  static const std::map<std::string, std::string> MIME_TYPES{
+      {".css", "text/css"},
+      {".png", "image/png"},
+      {".webp", "image/webp"},
+      {".ico", "image/vnd.microsoft.icon"},
+      {".svg", "image/svg+xml"},
+      {".webmanifest", "application/manifest+json"},
+      {".json", "application/json"},
+      {".woff", "font/woff"},
+      {".woff2", "font/woff2"},
+  };
+
+  std::string extension{file_path.extension().string()};
+  std::transform(extension.begin(), extension.end(), extension.begin(),
+                 [](const auto character) { return std::tolower(character); });
+  const auto result{MIME_TYPES.find(extension)};
+  return result == MIME_TYPES.cend() ? "application/octet-stream"
+                                     : result->second;
+}
+
+} // namespace sourcemeta::hydra::http

test/unit/http/CMakeLists.txt

@@ -1,5 +1,6 @@
 add_executable(sourcemeta_hydra_http_unit
-  time_test.cc status_test.cc method_test.cc header_test.cc)
+  time_test.cc status_test.cc method_test.cc
+  header_test.cc mime_test.cc)
 noa_add_default_options(PRIVATE sourcemeta_hydra_http_unit)
 target_link_libraries(sourcemeta_hydra_http_unit
   PRIVATE GTest::gtest GTest::gtest_main)

test/unit/http/mime_test.cc

@@ -0,0 +1,72 @@
+#include <gtest/gtest.h>
+
+#include <sourcemeta/hydra/http.h>
+
+TEST(HTTP_MIME, css_lower) {
+  const std::filesystem::path file_path{"path/to/example.css"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "text/css");
+}
+
+TEST(HTTP_MIME, css_upper) {
+  const std::filesystem::path file_path{"path/to/example.CSS"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "text/css");
+}
+
+TEST(HTTP_MIME, css_mixed) {
+  const std::filesystem::path file_path{"path/to/example.cSs"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "text/css");
+}
+
+TEST(HTTP_MIME, png_lower) {
+  const std::filesystem::path file_path{"path/to/example.png"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "image/png");
+}
+
+TEST(HTTP_MIME, webp_lower) {
+  const std::filesystem::path file_path{"path/to/example.webp"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "image/webp");
+}
+
+TEST(HTTP_MIME, ico_lower) {
+  const std::filesystem::path file_path{"path/to/example.ico"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path),
+            "image/vnd.microsoft.icon");
+}
+
+TEST(HTTP_MIME, svg_lower) {
+  const std::filesystem::path file_path{"path/to/example.svg"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "image/svg+xml");
+}
+
+TEST(HTTP_MIME, webmanifest_lower) {
+  const std::filesystem::path file_path{"path/to/example.webmanifest"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path),
+            "application/manifest+json");
+}
+
+TEST(HTTP_MIME, json_lower) {
+  const std::filesystem::path file_path{"path/to/example.json"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "application/json");
+}
+
+TEST(HTTP_MIME, woff_lower) {
+  const std::filesystem::path file_path{"path/to/example.woff"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "font/woff");
+}
+
+TEST(HTTP_MIME, woff2_lower) {
+  const std::filesystem::path file_path{"path/to/example.woff2"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path), "font/woff2");
+}
+
+TEST(HTTP_MIME, unknown) {
+  const std::filesystem::path file_path{"path/to/example.foobar"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path),
+            "application/octet-stream");
+}
+
+TEST(HTTP_MIME, none) {
+  const std::filesystem::path file_path{"path/to/example"};
+  EXPECT_EQ(sourcemeta::hydra::http::mime_type(file_path),
+            "application/octet-stream");
+}