Implement attachment query

src/app.cpp

@@ -2,7 +2,9 @@
 #include <ctime>
 #include <exception>
 #include <filesystem>
+#include <fstream>
 #include <iomanip>
+#include <iterator>
 #include <memory>
 #include <regex>
 #include <sstream>
@@ -572,6 +574,34 @@ void App::handleAttachments(const httplib::Request& req, httplib::Response& res)
     res.set_content(result, "text/html");
 }
 
+void App::handleAttachment(const httplib::Request& req, httplib::Response& res)
+{
+    ASSIGN_OR_RESPOND_ERROR(
+        std::optional<Attachment> att,
+        data->getAttachment(req.path_params.at("hash")),
+        res);
+    if(!att.has_value())
+    {
+        res.status = 404;
+        res.set_content("Attachment not found", "text/plain");
+        return;
+    }
+
+    namespace fs = std::filesystem;
+    auto path = fs::path(config.attachment_dir) / attachment_manager.path(*att);
+    if(!fs::exists(path))
+    {
+        res.status = 404;
+        res.set_content("File not found", "text/plain");
+        return;
+    }
+
+    std::ifstream file(path);
+    std::string data(std::istreambuf_iterator<char>{file}, {});
+    file.close();
+    res.set_content(data, att->content_type);
+}
+
 nlohmann::json App::postToJson(const Post& p) const
 {
     nlohmann::json result;
@@ -737,6 +767,11 @@ void App::start()
     {
         handleAttachments(req, res);
     });
+    server.Get(getPath("attachment", "hash/:_"),
+                [&](const httplib::Request& req, httplib::Response& res)
+    {
+        handleAttachment(req, res);
+    });
 
     spdlog::info("Listening at http://{}:{}/...", config.listen_address,
                  config.listen_port);

src/app.hpp

@@ -50,6 +50,7 @@ class App
     void handlePublishFromNewDraft(const httplib::Request& req,
                                    httplib::Response& res) const;
     void handleAttachments(const httplib::Request& req, httplib::Response& res);
+    void handleAttachment(const httplib::Request& req, httplib::Response& res);
 
     void start();
     void stop();

src/app_test.cpp

@@ -27,6 +27,7 @@ class UserAppTest : public testing::Test
         config.listen_address = "localhost";
         config.listen_port = 8080;
         config.data_dir = ".";
+        config.attachment_dir = "test-data";
         config.blog_title = "Test Blog";
 
         auto auth = std::make_unique<AuthMock>();
@@ -339,3 +340,25 @@ TEST_F(UserAppTest, CanHandleAttachments)
     app->stop();
     app->wait();
 }
+
+TEST_F(UserAppTest, CanHandleAttachment)
+{
+    Attachment att;
+    att.content_type = "image/png";
+    att.hash = "xyz";
+    att.original_name = "test.png";
+    att.upload_time = Clock::now();
+
+    EXPECT_CALL(*data_source, getAttachment("xyz")).WillOnce(Return(att));
+    app->start();
+    {
+        HTTPSession client;
+        ASSIGN_OR_FAIL(const HTTPResponse* res,
+                       client.get("http://localhost:8080/blog/attachment/xyz/test.png"));
+
+        EXPECT_EQ(res->status, 200) << "Response body: " << res->payloadAsStr();
+        EXPECT_EQ(res->payloadAsStr().size(), 313);
+    }
+    app->stop();
+    app->wait();
+}

src/config.cpp

@@ -52,6 +52,10 @@ E<Configuration> Configuration::fromYaml(const std::filesystem::path& path)
     {
         tree["data-dir"] >> config.data_dir;
     }
+    if(tree["attachment-dir"].has_key())
+    {
+        tree["attachment-dir"] >> config.attachment_dir;
+    }
     if(tree["listen-address"].has_key())
     {
         tree["listen-address"] >> config.listen_address;

src/config.hpp

@@ -13,6 +13,7 @@ struct Configuration
     using StringMap = std::unordered_map<std::string, std::string>;
 
     std::string data_dir;
+    std::string attachment_dir;
     std::string listen_address;
     int listen_port;
     std::string client_id;