Octoprint: Add a dialog for setting the filename/path

and a "print now" option
cf. #880, #245, #55, #87

xs/src/slic3r/Utils/Http.hpp

@@ -16,11 +16,11 @@ private:
 public:
 	struct Progress
 	{
-		size_t dltotal;
-		size_t dlnow;
-		size_t ultotal;
-		size_t ulnow;
-		
+		size_t dltotal;   // Total bytes to download
+		size_t dlnow;     // Bytes downloaded so far
+		size_t ultotal;   // Total bytes to upload
+		size_t ulnow;     // Bytes uploaded so far
+
 		Progress(size_t dltotal, size_t dlnow, size_t ultotal, size_t ulnow) :
 			dltotal(dltotal), dlnow(dlnow), ultotal(ultotal), ulnow(ulnow)
 		{}
@@ -33,6 +33,8 @@ public:
 
 	Http(Http &&other);
 
+	// These are the primary constructors that create a HTTP object
+	// for a GET and a POST request respectively.
 	static Http get(std::string url);
 	static Http post(std::string url);
 	~Http();
@@ -41,21 +43,42 @@ public:
 	Http& operator=(const Http &) = delete;
 	Http& operator=(Http &&) = delete;
 
+	// Sets a maximum size of the data that can be received. The default is 5MB.
 	Http& size_limit(size_t sizeLimit);
+	// Sets a HTTP header field.
 	Http& header(std::string name, const std::string &value);
+	// Removes a header field.
 	Http& remove_header(std::string name);
+	// Sets a CA certificate file for usage with HTTPS. This is only supported on some backends,
+	// specifically, this is supported with OpenSSL and NOT supported with Windows and OS X native certificate store.
+	// See also ca_file_supported().
 	Http& ca_file(const std::string &filename);
+	// Add a HTTP multipart form field
 	Http& form_add(const std::string &name, const std::string &contents);
-	Http& form_add_file(const std::string &name, const std::string &filename);
+	// Add a HTTP multipart form file data contents
+	Http& form_add_file(const std::string &name, const std::string &path);
+	// Same as above except also override the file's filename with a custom one
+	Http& form_add_file(const std::string &name, const std::string &path, const std::string &filename);
 
+	// Callback called on HTTP request complete
 	Http& on_complete(CompleteFn fn);
+	// Callback called on an error occuring at any stage of the requests: Url parsing, DNS lookup,
+	// TCP connection, HTTP transfer, and finally also when the response indicates an error (status >= 400).
+	// Therefore, a response body may or may not be present.
 	Http& on_error(ErrorFn fn);
+	// Callback called on data download/upload prorgess (called fairly frequently).
+	// See the `Progress` structure for description of the data passed.
+	// Writing a true-ish value into the cancel reference parameter cancels the request.
 	Http& on_progress(ProgressFn fn);
 
+	// Starts performing the request in a background thread
 	Ptr perform();
+	// Starts performing the request on the current thread
 	void perform_sync();
+	// Cancels a request in progress
 	void cancel();
 
+	// Tells whether current backend supports seting up a CA file using ca_file()
 	static bool ca_file_supported();
 private:
 	Http(const std::string &url);