Travel3: Simple image and video display site

Reads the images and videos from filesystem and builds a site in
memroy.

1 files changed, 147 insertions, 0 deletions

diff --git a/src/transport.hh b/src/transport.hh
new file mode 100644
index 0000000..5e6733f
--- /dev/null
+++ b/src/transport.hh
@@ -0,0 +1,147 @@
+#ifndef TRANSPORT_HH
+#define TRANSPORT_HH
+
+#include "unique_fd.hh"
+
+#include <filesystem>
+#include <functional>
+#include <memory>
+#include <optional>
+#include <string_view>
+#include <utility>
+#include <vector>
+
+class Buffer;
+class Config;
+class Logger;
+class Looper;
+class TaskRunner;
+
+class Transport {
+public:
+  class Request {
+  public:
+    virtual ~Request() = default;
+
+    virtual std::string_view method() const = 0;
+    virtual std::string_view path() const = 0;
+    virtual std::string_view query(std::string_view name) const = 0;
+    virtual std::optional<std::string> header_one(
+        std::string_view name) const = 0;
+    virtual std::vector<std::string> header_all(
+        std::string_view name) const = 0;
+  };
+
+  class Input {
+  public:
+    virtual ~Input() = default;
+
+    enum class Return {
+      OK,  // At least one byte was added to buffer.
+      FULL,  // Zero bytes added to buffer as it is full.
+      END, // Zero or more bytes added to buffer but there are no more bytes
+           // available because input has ended.
+      ERR, // No bytes added to buffer and there was an fatal error reading
+           // any more bytes.
+      WAIT,  // Zero or more bytes added to buffer but wait before calling
+             // fill again (see wait_once).
+    };
+
+    virtual Return fill(Buffer* buffer, size_t buf_request_size = 1) = 0;
+
+    // Setup callback to be called when Input is ready to be read again using
+    // looper. Callback will only be called once. Callback might be called
+    // before wait returns if Input is already ready. If Input is destroyed
+    // before getting ready the callback will never be called.
+    virtual void wait_once(std::shared_ptr<Looper> looper,
+                           std::function<void()> callback) = 0;
+
+  protected:
+    Input() = default;
+  };
+
+  class Response {
+  public:
+    virtual ~Response() = default;
+
+    virtual uint16_t code() const = 0;
+    virtual std::vector<std::pair<std::string, std::string>> const&
+        headers() const = 0;
+    // Only call this once. If it returns null, call open_content_async instead.
+    virtual std::unique_ptr<Input> open_content() = 0;
+    // Only call this once and only if open_content() first returned nullptr.
+    // If response is destroyed before callback is posted the callback will
+    // never be posted. But if callback is already posted then it will run,
+    // and the input will still be valid.
+    virtual void open_content_async(
+        std::shared_ptr<TaskRunner> runner,
+        std::function<void(std::unique_ptr<Input>)> callback);
+
+    virtual void add_header(std::string name, std::string value) = 0;
+
+  protected:
+    Response() = default;
+  };
+
+  std::unique_ptr<Response> create_ok_data(std::string data);
+  std::unique_ptr<Response> create_ok_file(std::filesystem::path path);
+  std::unique_ptr<Response> create_ok_exif_thumbnail(
+      std::filesystem::path path);
+  std::unique_ptr<Response> create_not_found();
+  std::unique_ptr<Response> create_redirect(std::string target,
+                                            bool temporary = true);
+  virtual std::unique_ptr<Response> create_data(
+      uint16_t code, std::string data) = 0;
+  virtual std::unique_ptr<Response> create_file(
+      uint16_t code, std::filesystem::path data) = 0;
+  virtual std::unique_ptr<Response> create_exif_thumbnail(
+      uint16_t code, std::filesystem::path data) = 0;
+
+  class Handler {
+  public:
+    virtual ~Handler() = default;
+
+    virtual std::unique_ptr<Response> request(Transport* transport,
+                                              Request const* request) = 0;
+
+  protected:
+    Handler() = default;
+  };
+
+  // Takes care of GET/HEAD, optional cache headers and general housekeeping.
+  // Also removes // and similar from paths.
+  static std::unique_ptr<Handler> create_default_handler(
+      std::shared_ptr<Logger> logger,
+      Handler* handler);
+
+  class Factory {
+  public:
+    virtual ~Factory() = default;
+
+    virtual std::unique_ptr<Transport> create(
+        std::shared_ptr<Logger> logger,
+        std::shared_ptr<Looper> looper,
+        std::shared_ptr<TaskRunner> runner,
+        // config_logger is used to write any errors during create
+        // when reading the config. No reference kept as with logger.
+        Logger* config_logger,
+        Config const* config,
+        Handler* handler) = 0;
+
+  protected:
+    Factory() = default;
+    Factory(Factory const&) = delete;
+    Factory& operator=(Factory const&) = delete;
+  };
+
+  virtual ~Transport() = default;
+
+  virtual void add_client(unique_fd&& fd) = 0;
+
+protected:
+  Transport() = default;
+  Transport(Transport const&) = delete;
+  Transport& operator=(Transport const&) = delete;
+};
+
+#endif  // TRANSPORT_HH