Post/upload files support.

examples/http_client.cc

@@ -91,7 +91,7 @@ void ExampleCompression() {
 }
 
 // Get an image from HttpBin.org and save to the given file path.
-// E.g., ExampleImage("E:\\example.jpeg")
+// E.g., ExampleImage("E:\\example.jpg")
 void ExampleImage(const std::string& path) {
   HttpClientSession session;
 
@@ -105,6 +105,35 @@ void ExampleImage(const std::string& path) {
   ofs << r->content();
 }
 
+// Post/upload files.
+void ExamplePostFiles() {
+  HttpClientSession session;
+
+  auto r = session.Request(HttpRequestBuilder{}
+                               .Post()
+                               .url("http://httpbin.org/post")
+                               .file_data("file1", "report.xls", "<xls report data>", "application/vnd.ms-excel")
+                               .file_data("file2", "report.xml", "<xml report data>", "text/xml")());
+
+  std::cout << r->content() << std::endl;
+}
+
+// Post/upload files by file path.
+void ExamplePostFiles(const std::string& name,
+                      const std::string& file_name,
+                      const std::string& file_path,
+                      const std::string& content_type) {
+  HttpClientSession session;
+
+  auto r =
+      session.Request(HttpRequestBuilder{}
+                          .Post()
+                          .url("http://httpbin.org/post")
+                          .file(name, file_name, file_path, content_type)());
+
+  std::cout << r->content() << std::endl;
+}
+
 int main() {
   WEBCC_LOG_INIT("", LOG_CONSOLE);
 

webcc/globals.cc

@@ -31,6 +31,8 @@ const char* DescribeError(Error error) {
       return "HTTP error";
     case kServerError:
       return "Server error";
+    case kFileIOError:
+      return "File IO error";
     case kXmlError:
       return "XML error";
     default:
@@ -38,14 +40,14 @@ const char* DescribeError(Error error) {
   }
 }
 
-Exception::Exception(Error error, bool timeout, const std::string& details)
-    : error_(error), timeout_(timeout), msg_(DescribeError(error)) {
-  if (timeout) {
-    msg_ += " (timeout)";
-  }
+Exception::Exception(Error error, const std::string& details, bool timeout)
+    : error_(error), msg_(DescribeError(error)), timeout_(timeout) {
   if (!details.empty()) {
     msg_ += " (" + details + ")";
   }
+  if (timeout) {
+    msg_ += " (timeout)";
+  }
 }
 
 }  // namespace webcc

webcc/globals.h

@@ -145,6 +145,9 @@ enum Error {
   // E.g., HTTP status 500 + SOAP Fault element.
   kServerError,
 
+  // File read/write error.
+  kFileIOError,
+
   // XML parsing error.
   kXmlError,
 };
@@ -154,25 +157,25 @@ const char* DescribeError(Error error);
 
 class Exception : public std::exception {
 public:
-  explicit Exception(Error error = kNoError, bool timeout = false,
-                     const std::string& details = "");
+  explicit Exception(Error error, const std::string& details = "",
+                     bool timeout = false);
+
+  Error error() const { return error_; }
 
   // Note that `noexcept` is required by GCC.
   const char* what() const noexcept override {
     return msg_.c_str();
   }
 
-  Error error() const { return error_; }
-
   bool timeout() const { return timeout_; }
 
 private:
   Error error_;
 
+  std::string msg_;
+
   // If the error was caused by timeout or not.
   bool timeout_;
-
-  std::string msg_;
 };
 
 }  // namespace webcc

webcc/http_client_session.cc

@@ -172,7 +172,7 @@ HttpResponsePtr HttpClientSession::Send(HttpRequestPtr request) {
       // Remove the failed connection from pool.
       pool_.Remove(key);
     }
-    throw Exception(client->error(), client->timed_out());
+    throw Exception(client->error(), "", client->timed_out());
   }
 
   // Update connection pool.

webcc/http_message.cc

@@ -179,7 +179,7 @@ void HttpMessage::Dump(std::ostream& os, std::size_t indent,
     } else {
       // Split by EOL to achieve more readability.
       std::vector<std::string> splitted;
-      boost::split(splitted, content_, boost::is_any_of(kCRLF));
+      boost::split(splitted, content_, boost::is_any_of("\n"));
 
       std::size_t size = 0;
 

webcc/http_message.h

@@ -108,6 +108,10 @@ public:
   // Return true if header Accept-Encoding contains "gzip".
   bool AcceptEncodingGzip() const;
 
+  void SetContentType(const std::string& content_type) {
+    SetHeader(http::headers::kContentType, content_type);
+  }
+
   // E.g., "text/html", "application/json; charset=utf-8", etc.
   void SetContentType(const std::string& media_type,
                       const std::string& charset);

webcc/http_request_builder.cc

@@ -1,10 +1,32 @@
 #include "webcc/http_request_builder.h"
 
+#include <fstream>
+
 #include "webcc/logger.h"
+#include "webcc/utility.h"
 #include "webcc/zlib_wrapper.h"
 
 namespace webcc {
 
+// -----------------------------------------------------------------------------
+
+// Read entire file into string.
+static bool ReadFile(const std::string& path, std::string* output) {
+  std::ifstream ifs{path, std::ios::binary | std::ios::ate};
+  if (!ifs) {
+    return false;
+  }
+
+  auto size = ifs.tellg();
+  output->resize(size, '\0');
+  ifs.seekg(0);
+  ifs.read(&(*output)[0], size);  // TODO: Error handling
+
+  return true;
+}
+
+// -----------------------------------------------------------------------------
+
 HttpRequestPtr HttpRequestBuilder::operator()() {
   assert(parameters_.size() % 2 == 0);
   assert(headers_.size() % 2 == 0);
@@ -25,26 +47,90 @@ HttpRequestPtr HttpRequestBuilder::operator()() {
   }
 
   if (!data_.empty()) {
-    if (gzip_ && data_.size() > kGzipThreshold) {
-      std::string compressed;
-      if (Compress(data_, &compressed)) {
-        request->SetContent(std::move(compressed), true);
-        request->SetHeader(http::headers::kContentEncoding, "gzip");
-      } else {
-        LOG_WARN("Cannot compress the content data!");
-        request->SetContent(std::move(data_), true);
-      }
-    } else {
-      request->SetContent(std::move(data_), true);
-    }
+    SetContent(request, std::move(data_));
 
     // TODO: Request-level charset.
     if (json_) {
       request->SetContentType(http::media_types::kApplicationJson, "");
     }
+  } else if (!files_.empty()) {
+    // Another choice to generate the boundary is what Apache does, see:
+    //   https://stackoverflow.com/a/5686863
+    const std::string boundary = RandomUuid();
+
+    request->SetContentType("multipart/form-data; boundary=" + boundary);
+
+    std::string data;
+    CreateFormData(&data, boundary);
+
+    // Ingore gzip since most servers don't support it. 
+    request->SetContent(std::move(data), true);
   }
 
   return request;
 }
 
+HttpRequestBuilder& HttpRequestBuilder::file(const std::string& name,
+                                             const std::string& file_name,
+                                             const std::string& file_path,
+                                             const std::string& content_type) {
+  std::string file_data;
+  if (!ReadFile(file_path, &file_data)) {
+    throw Exception(kFileIOError, "Cannot read the file.");
+  }
+
+  files_.push_back({name, file_name, std::move(file_data), content_type});
+
+  return *this;
+}
+
+void HttpRequestBuilder::SetContent(HttpRequestPtr request,
+                                    std::string&& data) {
+  if (gzip_ && data.size() > kGzipThreshold) {
+    std::string compressed;
+    if (Compress(data, &compressed)) {
+      request->SetContent(std::move(compressed), true);
+      request->SetHeader(http::headers::kContentEncoding, "gzip");
+      return;
+    }
+
+    LOG_WARN("Cannot compress the content data!");
+  }
+
+  request->SetContent(std::move(data), true);
+}
+
+void HttpRequestBuilder::CreateFormData(std::string* data,
+                                        const std::string& boundary) {
+  for (File& file : files_) {
+    data->append("--" + boundary + kCRLF);
+
+    // Content-Disposition header
+    data->append("Content-Disposition: form-data");
+    if (!file.name.empty()) {
+      data->append("; name=\"" + file.name + "\"");
+    }
+    if (!file.file_name.empty()) {
+      data->append("; filename=\"" + file.file_name + "\"");
+    }
+    data->append(kCRLF);
+
+    // Content-Type header
+    if (!file.content_type.empty()) {
+      data->append("Content-Type: " + file.content_type);
+      data->append(kCRLF);
+    }
+
+    data->append(kCRLF);
+
+    // Payload
+    data->append(file.file_data);
+
+    data->append(kCRLF);
+  }
+
+  data->append("--" + boundary + "--");
+  data->append(kCRLF);
+}
+
 }  // namespace webcc

webcc/http_request_builder.h

@@ -51,12 +51,27 @@ public:
     return *this;
   }
 
-  HttpRequestBuilder& json(bool json) {
+  HttpRequestBuilder& json(bool json = true) {
     json_ = json;
     return *this;
   }
 
-  HttpRequestBuilder& gzip(bool gzip) {
+  // Upload a file with its path.
+  HttpRequestBuilder& file(const std::string& name,
+                           const std::string& file_name,
+                           const std::string& file_path,  // TODO: UNICODE
+                           const std::string& content_type = "");
+
+  // Upload a file with its data.
+  HttpRequestBuilder& file_data(const std::string& name,
+                                const std::string& file_name,
+                                std::string&& file_data,
+                                const std::string& content_type = "") {
+    files_.push_back({name, file_name, file_data, content_type});
+    return *this;
+  }
+
+  HttpRequestBuilder& gzip(bool gzip = true) {
     gzip_ = gzip;
     return *this;
   }
@@ -73,6 +88,11 @@ public:
     return *this;
   }
 
+private:
+  void SetContent(HttpRequestPtr request, std::string&& data);
+
+  void CreateFormData(std::string* data, const std::string& boundary);
+  
 private:
   std::string method_;
 
@@ -87,6 +107,19 @@ private:
   // Is the data to send a JSON string?
   bool json_ = false;
 
+  // Examples:
+  //   { "images", "example.jpg", "BinaryData", "image/jpeg" }
+  //   { "file", "report.csv", "BinaryData", "" }
+  struct File {
+    std::string name;
+    std::string file_name;
+    std::string file_data;  // Binary file data
+    std::string content_type;
+  };
+
+  // Files to upload for a POST (or PUT?) request.
+  std::vector<File> files_;
+
   // Compress the request content.
   // NOTE: Most servers don't support compressed requests.
   // Even the requests module from Python doesn't have a built-in support.

webcc/utility.cc

@@ -6,6 +6,9 @@
 #include <ostream>
 #include <sstream>
 
+#include "boost/uuid/random_generator.hpp"
+#include "boost/uuid/uuid_io.hpp"
+
 #include "webcc/logger.h"
 
 using tcp = boost::asio::ip::tcp;
@@ -44,4 +47,11 @@ std::string GetHttpDateTimestamp() {
   return ss.str();
 }
 
+std::string RandomUuid() {
+  boost::uuids::uuid u = boost::uuids::random_generator()();
+  std::stringstream ss;
+  ss << u;
+  return ss.str();
+}
+
 }  // namespace webcc

webcc/utility.h

@@ -22,6 +22,8 @@ std::string EndpointToString(const TcpEndpoint& endpoint);
 // See: https://tools.ietf.org/html/rfc7231#section-7.1.1.2
 std::string GetHttpDateTimestamp();
 
+std::string RandomUuid();
+
 }  // namespace webcc
 
 #endif  // WEBCC_UTILITY_H_

webcc/zlib_wrapper.cc

@@ -39,9 +39,7 @@ bool Compress(const std::string& input, std::string* output) {
 
     int err = deflate(&stream, Z_FINISH);
 
-    assert(err != Z_STREAM_ERROR);
-
-    if (err != Z_OK) {
+    if (err != Z_OK && err != Z_STREAM_END) {
       deflateEnd(&stream);
       if (stream.msg != nullptr) {
         LOG_ERRO("zlib deflate error: %s", stream.msg);
@@ -51,6 +49,7 @@ bool Compress(const std::string& input, std::string* output) {
 
     std::size_t size = buf.size() - stream.avail_out;
     output->insert(output->end(), buf.data(), buf.data() + size);
+
   } while (stream.avail_out == 0);
 
   if (deflateEnd(&stream) != Z_OK) {
@@ -105,7 +104,8 @@ bool Decompress(const std::string& input, std::string* output) {
 
     if (err == Z_STREAM_END) {
       break;
-    } else if (err != Z_OK) {
+    }
+    if (err != Z_OK) {
       inflateEnd(&stream);
       if (stream.msg != nullptr) {
         LOG_ERRO("zlib inflate error: %s", stream.msg);