Stop Malformed Network Responses from Crashing the App

Duet, MKS and UltiMaker parsed print host replies with boost read_json
inside the HTTP completion callback with no try, so an HTML or truncated
reply threw out of the Physical Printer Test button and terminated the app,
or killed the upload queue thread. The five identical copies of the parser
(ESP3D's and Flashforge's were unused) are replaced by one shared
PrintHost::get_err_code_from_body that reports a non-JSON reply as an error.
The upload queue now catches a failing job per job, so one bad upload no
longer leaves later jobs queued forever.

Flashforge read material station slots with nlohmann value(), which throws
on off-type fields or non-object entries. The parsing moves into
Flashforge::parse_material_slots, which reads fields leniently with the
existing try_parse_json_int and skips bad entries.

UserManager::parse_json parsed the payload before its try block; the parse
now happens inside it.

src/libslic3r/Format/3mf.cpp

@@ -307,17 +307,14 @@ bool PrusaFileParser::check_3mf_from_prusa(const std::string filename)
 
             mz_zip_archive_file_stat stat;
             if (!mz_zip_reader_file_stat(&archive, model_file_index, &stat)) goto EXIT;
-            // expat sizes its buffer with an int, so a larger entry cannot be parsed in one piece.
-            if (stat.m_uncomp_size > static_cast<mz_uint64>(std::numeric_limits<int>::max())) goto EXIT;
 
-            const int xml_size = static_cast<int>(stat.m_uncomp_size);
-            void *parser_buffer = XML_GetBuffer(m_parser, xml_size);
+            void *parser_buffer = XML_GetBuffer(m_parser, (int) stat.m_uncomp_size);
             if (parser_buffer == nullptr) goto EXIT;
 
-            mz_bool res = mz_zip_reader_extract_file_to_mem(&archive, stat.m_filename, parser_buffer, static_cast<size_t>(xml_size), 0);
+            mz_bool res = mz_zip_reader_extract_file_to_mem(&archive, stat.m_filename, parser_buffer, (size_t) stat.m_uncomp_size, 0);
             if (res == 0) goto EXIT;
 
-            XML_ParseBuffer(m_parser, xml_size, 1);
+            XML_ParseBuffer(m_parser, (int) stat.m_uncomp_size, 1);
         }
     }
 
@@ -1349,26 +1346,19 @@ ModelVolumeType type_from_string(const std::string &s)
         XML_SetUserData(m_xml_parser, (void*)this);
         XML_SetElementHandler(m_xml_parser, _3MF_Importer::_handle_start_config_xml_element, _3MF_Importer::_handle_end_config_xml_element);
 
-        // expat sizes its buffer with an int, so a larger entry cannot be parsed in one piece.
-        if (stat.m_uncomp_size > static_cast<mz_uint64>(std::numeric_limits<int>::max())) {
-            add_error("Found invalid size");
-            return false;
-        }
-        const int xml_size = static_cast<int>(stat.m_uncomp_size);
-
-        void* parser_buffer = XML_GetBuffer(m_xml_parser, xml_size);
+        void* parser_buffer = XML_GetBuffer(m_xml_parser, (int)stat.m_uncomp_size);
         if (parser_buffer == nullptr) {
             add_error("Unable to create buffer");
             return false;
         }
 
-        mz_bool res = mz_zip_reader_extract_file_to_mem(&archive, stat.m_filename, parser_buffer, static_cast<size_t>(xml_size), 0);
+        mz_bool res = mz_zip_reader_extract_file_to_mem(&archive, stat.m_filename, parser_buffer, (size_t)stat.m_uncomp_size, 0);
         if (res == 0) {
             add_error("Error while reading config data to buffer");
             return false;
         }
 
-        if (!XML_ParseBuffer(m_xml_parser, xml_size, 1)) {
+        if (!XML_ParseBuffer(m_xml_parser, (int)stat.m_uncomp_size, 1)) {
             char error_buf[1024];
             ::sprintf(error_buf, "Error (%s) while parsing xml file at line %d", XML_ErrorString(XML_GetErrorCode(m_xml_parser)), (int)XML_GetCurrentLineNumber(m_xml_parser));
             add_error(error_buf);

src/libslic3r/Format/bbs_3mf.cpp

@@ -2508,26 +2508,19 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
         XML_SetEntityDeclHandler(m_xml_parser, nullptr);
         XML_SetExternalEntityRefHandler(m_xml_parser, nullptr);
 
-        // expat sizes its buffer with an int, so a larger entry cannot be parsed in one piece.
-        if (stat.m_uncomp_size > static_cast<mz_uint64>(std::numeric_limits<int>::max())) {
-            add_error("Found invalid size");
-            return false;
-        }
-        const int xml_size = static_cast<int>(stat.m_uncomp_size);
-
-        void* parser_buffer = XML_GetBuffer(m_xml_parser, xml_size);
+        void* parser_buffer = XML_GetBuffer(m_xml_parser, (int)stat.m_uncomp_size);
         if (parser_buffer == nullptr) {
             add_error("Unable to create buffer");
             return false;
         }
 
-        mz_bool res = mz_zip_reader_extract_file_to_mem(&archive, stat.m_filename, parser_buffer, static_cast<size_t>(xml_size), 0);
+        mz_bool res = mz_zip_reader_extract_file_to_mem(&archive, stat.m_filename, parser_buffer, (size_t)stat.m_uncomp_size, 0);
         if (res == 0) {
             add_error("Error while reading config data to buffer");
             return false;
         }
 
-        if (!XML_ParseBuffer(m_xml_parser, xml_size, 1)) {
+        if (!XML_ParseBuffer(m_xml_parser, (int)stat.m_uncomp_size, 1)) {
             char error_buf[1024];
             ::snprintf(error_buf, 1024, "Error (%s) while parsing xml file at line %d", XML_ErrorString(XML_GetErrorCode(m_xml_parser)), (int)XML_GetCurrentLineNumber(m_xml_parser));
             add_error(error_buf);

src/libslic3r/GCode.cpp

@@ -2504,7 +2504,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(print->model().id().id);
+        ctx.id = std::to_string(print->model().id().id);
+        ctx.name = print->get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.msg  = path;
         ctx.cancellation_check = [print]() { return print->canceled(); };
@@ -2556,7 +2557,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
         }
         {
             LifecycleEventContext ctx;
-            ctx.name = std::to_string(print->model().id().id);
+            ctx.id = std::to_string(print->model().id().id);
+            ctx.name = print->get_model_name();
             ctx.code = LifecycleEvtCode::Error;
             ctx.msg  = std::string(path) + "\n" + err_msg;
             ctx.cancellation_check = [print]() { return print->canceled(); };
@@ -2580,7 +2582,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
         boost::nowide::remove(path_tmp.c_str());
         {
             LifecycleEventContext ctx;
-            ctx.name = std::to_string(print->model().id().id);
+            ctx.id = std::to_string(print->model().id().id);
+            ctx.name = print->get_model_name();
             ctx.code = LifecycleEvtCode::Error;
             ctx.msg  = std::string(path) + "\n" + ex.what();
             ctx.cancellation_check = [print]() { return print->canceled(); };
@@ -2693,7 +2696,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
     if (ret) {
         {
             LifecycleEventContext ctx;
-            ctx.name = std::to_string(print->model().id().id);
+            ctx.id = std::to_string(print->model().id().id);
+            ctx.name = print->get_model_name();
             ctx.code = LifecycleEvtCode::Error;
             ctx.msg  = std::string(path) + "\nFailed to rename the output G-code file: " + ret.message();
             ctx.cancellation_check = [print]() { return print->canceled(); };
@@ -2712,7 +2716,8 @@ void GCode::do_export(Print* print, const char* path, GCodeProcessorResult* resu
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(print->model().id().id);
+        ctx.id = std::to_string(print->model().id().id);
+        ctx.name = print->get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.msg  = path;
         ctx.cancellation_check = [print]() { return print->canceled(); };

src/libslic3r/Print.cpp

@@ -2717,7 +2717,8 @@ void Print::process(long long *time_cost_with_cache, bool use_cache)
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(m_model.id().id);
+        ctx.id = std::to_string(m_model.id().id);
+        ctx.name = get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.cancellation_check = [this]() { return canceled(); };
         fire_lifecycle_event(LifecycleEvent::SliceStarted, ctx);
@@ -3344,7 +3345,8 @@ void Print::process(long long *time_cost_with_cache, bool use_cache)
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(m_model.id().id);
+        ctx.id = std::to_string(m_model.id().id);
+        ctx.name = get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.cancellation_check = [this]() { return canceled(); };
         fire_lifecycle_event(LifecycleEvent::SliceGeometryFinished, ctx);
@@ -4950,7 +4952,8 @@ void Print::export_gcode_from_previous_file(const std::string& file, GCodeProces
 {
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(m_model.id().id);
+        ctx.id = std::to_string(m_model.id().id);
+        ctx.name = get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.msg  = file;
         ctx.cancellation_check = [this]() { return canceled(); };
@@ -4980,7 +4983,8 @@ void Print::export_gcode_from_previous_file(const std::string& file, GCodeProces
         BOOST_LOG_TRIVIAL(error) << __FUNCTION__ <<  boost::format(": found errors when process gcode file %1%") %file.c_str();
         {
             LifecycleEventContext ctx;
-            ctx.name = std::to_string(m_model.id().id);
+            ctx.id = std::to_string(m_model.id().id);
+            ctx.name = get_model_name();
             ctx.code = LifecycleEvtCode::Error;
             ctx.msg  = file + "\n" + ex.what();
             ctx.cancellation_check = [this]() { return canceled(); };
@@ -4994,7 +4998,8 @@ void Print::export_gcode_from_previous_file(const std::string& file, GCodeProces
 
     {
         LifecycleEventContext ctx;
-        ctx.name = std::to_string(m_model.id().id);
+        ctx.id = std::to_string(m_model.id().id);
+        ctx.name = get_model_name();
         ctx.code = LifecycleEvtCode::Ok;
         ctx.msg  = file;
         ctx.cancellation_check = [this]() { return canceled(); };

src/slic3r/GUI/Plater.cpp

@@ -12800,8 +12800,6 @@ void Plater::priv::on_process_completed(SlicingProcessCompletedEvent &evt)
     notification_manager->set_slicing_progress_export_possible();
 
     // Reset the "export G-code path" name, so that the automatic background processing will be enabled again.
-    const std::string lifecycle_job_name = this->background_process.fff_print() ?
-        this->background_process.fff_print()->output_filename() : std::string();
     this->background_process.reset_export();
     // This bool stops showing export finished notification even when process_completed_with_error is false
     bool has_error = false;
@@ -12848,8 +12846,18 @@ void Plater::priv::on_process_completed(SlicingProcessCompletedEvent &evt)
 
     {
         Slic3r::LifecycleEventContext ctx;
-        ctx.name = lifecycle_job_name;
-        ctx.code = evt.cancelled() ? Slic3r::LifecycleEvtCode::Warn : (has_error ? Slic3r::LifecycleEvtCode::Error : Slic3r::LifecycleEvtCode::Ok);
+        if (const PrintBase* print = this->background_process.current_print()) {
+            const Model& model = print->model();
+            ctx.id             = std::to_string(model.id().id);
+            if (model.model_info)
+                ctx.name = model.model_info->model_name;
+        } else {
+            // Realistically Printbase* print will never be null because select_technology already asserts an active print
+            // and the worker thread asserts it before processing.
+            BOOST_LOG_TRIVIAL(warning) << __FUNCTION__ << ": slicing completed without an active print; lifecycle event has no model ID";
+        }
+        ctx.code = evt.cancelled() ? Slic3r::LifecycleEvtCode::Warn :
+                                     (has_error ? Slic3r::LifecycleEvtCode::Error : Slic3r::LifecycleEvtCode::Ok);
         ctx.msg  = evt.cancelled() ? "cancelled" : (has_error ? lifecycle_error_msg : std::string());
         Slic3r::fire_lifecycle_event(Slic3r::LifecycleEvent::SlicingJobComplete, ctx);
     }

src/slic3r/GUI/UserManager.cpp

@@ -31,14 +31,15 @@ int UserManager::parse_json(std::string payload)
 {
     bool restored_json = false;
     json j;
-    json j_pre = json::parse(payload);
-    if (j_pre.empty()) {
-        return -1;
-    }
 
     //bind/unbind
 
     try {
+        json j_pre = json::parse(payload);
+        if (j_pre.empty()) {
+            return -1;
+        }
+
         if (j_pre.contains("bind")) {
             if (j_pre["bind"].contains("command")) {
 

src/slic3r/Utils/Duet.cpp

@@ -274,13 +274,4 @@ bool Duet::start_print(wxString &msg, const std::string &filename, ConnectionTyp
 	return res;
 }
 
-int Duet::get_err_code_from_body(const std::string &body) const
-{
-	pt::ptree root;
-	std::istringstream iss (body); // wrap returned json to istringstream
-	pt::read_json(iss, root);
-
-	return root.get<int>("err", 0);
-}
-
 }

src/slic3r/Utils/Duet.hpp

@@ -40,7 +40,6 @@ private:
 	ConnectionType connect(wxString &msg) const;
 	void disconnect(ConnectionType connectionType) const;
 	bool start_print(wxString &msg, const std::string &filename, ConnectionType connectionType, bool simulationMode) const;
-	int get_err_code_from_body(const std::string &body) const;
 };
 
 }

src/slic3r/Utils/ESP3D.cpp

@@ -146,15 +146,6 @@ bool ESP3D::start_print(wxString& msg, const std::string& filename) const
     return ret;
 }
 
-int ESP3D::get_err_code_from_body(const std::string& body) const
-{
-    pt::ptree          root;
-    std::istringstream iss(body); // wrap returned json to istringstream
-    pt::read_json(iss, root);
-
-    return root.get<int>("err", 0);
-}
-
 // ESP3D only accepts 8.3 filenames else it crashes marlin and other undefined behaviour
 std::string ESP3D::get_short_name(const std::string& filename) const
 {

src/slic3r/Utils/ESP3D.hpp

@@ -33,7 +33,6 @@ private:
     std::string m_console_port;
 
     bool        start_print(wxString& msg, const std::string& filename) const;
-    int         get_err_code_from_body(const std::string& body) const;
     std::string get_short_name(const std::string& filename) const;
     std::string format_command(const std::string& path, const std::string& arg, const std::string& val) const;
 };

src/slic3r/Utils/Flashforge.cpp

@@ -510,12 +510,22 @@ bool Flashforge::fetch_material_slots(std::vector<FlashforgeMaterialSlot>& slots
     if (!request_local_api_json("detail", json{{"serialNumber", m_serial_number}, {"checkCode", m_check_code}}.dump(), body, msg))
         return false;
 
-    const auto parsed = json::parse(body, nullptr, false, true);
-    if (parsed.is_discarded()) {
+    if (!parse_material_slots(body, slots, supports_material_station)) {
         msg = _(L("Flashforge returned an invalid JSON response."));
         return false;
     }
 
+    return true;
+}
+
+bool Flashforge::parse_material_slots(const std::string& body, std::vector<FlashforgeMaterialSlot>& slots, bool* supports_material_station)
+{
+    slots.clear();
+
+    const auto parsed = json::parse(body, nullptr, false, true);
+    if (parsed.is_discarded())
+        return false;
+
     const auto& detail = parsed.contains("detail") ? parsed["detail"] : parsed;
     const auto& station = detail.contains("matlStationInfo") ? detail["matlStationInfo"] :
                           detail.contains("MatlStationInfo") ? detail["MatlStationInfo"] : json();
@@ -542,12 +552,21 @@ bool Flashforge::fetch_material_slots(std::vector<FlashforgeMaterialSlot>& slots
     if (supports_material_station != nullptr)
         *supports_material_station = reports_material_station;
 
+    // Fields are read leniently: firmware may send numbers as strings or flags as numbers.
     for (const auto& slot : slot_infos) {
+        if (!slot.is_object())
+            continue;
         FlashforgeMaterialSlot info;
-        info.slot_id        = slot.value("slotId", static_cast<int>(slots.size()) + 1);
-        info.has_filament   = slot.value("hasFilament", false);
-        info.material_name  = slot.value("materialName", std::string());
-        info.material_color = slot.value("materialColor", std::string());
+        info.slot_id = static_cast<int>(slots.size()) + 1;
+        if (const auto it = slot.find("slotId"); it != slot.end())
+            try_parse_json_int(*it, info.slot_id);
+        int has_filament = 0;
+        if (const auto it = slot.find("hasFilament"); it != slot.end() && try_parse_json_int(*it, has_filament))
+            info.has_filament = has_filament != 0;
+        if (const auto it = slot.find("materialName"); it != slot.end() && it->is_string())
+            info.material_name = it->get<std::string>();
+        if (const auto it = slot.find("materialColor"); it != slot.end() && it->is_string())
+            info.material_color = it->get<std::string>();
         slots.emplace_back(std::move(info));
     }
 
@@ -670,13 +689,4 @@ std::string Flashforge::extract_host_name() const
     return out;
 }
 
-int Flashforge::get_err_code_from_body(const std::string& body) const
-{
-    pt::ptree          root;
-    std::istringstream iss(body); // wrap returned json to istringstream
-    pt::read_json(iss, root);
-
-    return root.get<int>("err", 0);
-}
-
 } // namespace Slic3r

src/slic3r/Utils/Flashforge.hpp

@@ -45,6 +45,8 @@ public:
     PrintHostPostUploadActions get_post_upload_actions() const override { return PrintHostPostUploadAction::StartPrint; }
     std::string                get_host() const override { return m_host; }
     bool                       fetch_material_slots(std::vector<FlashforgeMaterialSlot>& slots, bool* supports_material_station, wxString& msg) const;
+    // Parses a local API "detail" reply. Returns false when the body is not valid JSON.
+    static bool                parse_material_slots(const std::string& body, std::vector<FlashforgeMaterialSlot>& slots, bool* supports_material_station);
     static bool                discover_printers(std::vector<FlashforgeDiscoveredPrinter>& printers, wxString& msg, int timeout_ms = 10000, int idle_timeout_ms = 1500, int max_retries = 3);
 
 private:
@@ -68,7 +70,6 @@ private:
     bool request_local_api_json(const std::string& path, const std::string& body, std::string& response_body, wxString& error_msg) const;
     std::string make_http_url(const std::string& path) const;
     std::string extract_host_name() const;
-    int  get_err_code_from_body(const std::string &body) const;
     bool connect(wxString& msg) const;
     bool start_print(wxString& msg, const std::string& filename) const;
 };

src/slic3r/Utils/MKS.cpp

@@ -141,13 +141,4 @@ bool MKS::start_print(wxString& msg, const std::string& filename) const
 	return ret;
 }
 
-int MKS::get_err_code_from_body(const std::string& body) const
-{
-	pt::ptree root;
-	std::istringstream iss(body); // wrap returned json to istringstream
-	pt::read_json(iss, root);
-
-	return root.get<int>("err", 0);
-}
-
 } // Slic3r

src/slic3r/Utils/MKS.hpp

@@ -34,7 +34,6 @@ private:
 
 	std::string get_upload_url(const std::string& filename) const;
 	bool start_print(wxString& msg, const std::string& filename) const;
-	int get_err_code_from_body(const std::string& body) const;
 };
 
 }

src/slic3r/Utils/PrintHost.cpp

@@ -3,9 +3,13 @@
 #include <vector>
 #include <thread>
 #include <exception>
+#include <sstream>
 #include <boost/optional.hpp>
 #include <boost/log/trivial.hpp>
 #include <boost/filesystem.hpp>
+#include <nlohmann/json.hpp>
+#include <boost/property_tree/ptree.hpp>
+#include <boost/property_tree/json_parser.hpp>
 
 #include <wx/string.h>
 #include <wx/app.h>
@@ -115,10 +119,81 @@ std::string PrintHost::get_print_host_webui(DynamicPrintConfig* config)
     return webui_url;
 }
 
+namespace {
+
+// Moonraker (Klipper's API server) reports a raised exception as { "error": { "code", "message", "traceback" } }
+// under every host type that connects to it, often with the cause only in the traceback. Returns the reason to show,
+// or empty for any other body.
+std::string moonraker_error_reason(const std::string &body)
+{
+    const auto root = nlohmann::json::parse(body, nullptr, false);
+    const auto err  = root.find("error");
+    if (err == root.end())
+        return {};
+    const auto message   = err->find("message");
+    const auto traceback = err->find("traceback");
+    if (message == err->end() || traceback == err->end() || !message->is_string() || !traceback->is_string())
+        return {};
+
+    const auto &msg = message->get_ref<const std::string &>();
+    const auto &tb  = traceback->get_ref<const std::string &>();
+    if (msg.empty())
+        return {};
+    const auto end = tb.find_last_not_of(" \t\r\n");
+    if (end == std::string::npos)
+        return msg;
+
+    // Chained exceptions each start a new traceback; the one that failed the request is the last.
+    const auto header = tb.rfind("Traceback (most recent call last):", end);
+
+    // Tornado renders a raised HTTPError as "HTTP <code>: <reason>[ (<detail>)]", and the detail may span lines.
+    const auto code = err->find("code");
+    if (code != err->end() && code->is_number_integer()) {
+        const std::string marker = "HTTP " + std::to_string(code->get<int>()) + ": ";
+        const auto        pos    = tb.rfind(marker, end);
+        if (pos != std::string::npos && (header == std::string::npos || pos > header) && pos + marker.size() <= end) {
+            const std::string reason = tb.substr(pos + marker.size(), end + 1 - pos - marker.size());
+            // An HTTPError whose detail equals its reason, like HTTPError(401, "Unauthorized"), renders the phrase twice.
+            return reason == msg + " (" + msg + ")" ? msg : reason;
+        }
+    }
+
+    // Any other exception's type and message are everything from the first unindented line after its frames.
+    auto begin = (header == std::string::npos) ? std::string::npos : tb.find('\n', header);
+    while (begin != std::string::npos && begin < end) {
+        ++begin;
+        if (tb[begin] != ' ' && tb[begin] != '\r' && tb[begin] != '\n')
+            break;
+        begin = tb.find('\n', begin);
+    }
+    if (begin == std::string::npos || begin > end) {
+        const auto nl = tb.rfind('\n', end);
+        begin         = (nl == std::string::npos) ? 0 : nl + 1;
+    }
+    return msg + " (" + tb.substr(begin, end + 1 - begin) + ")";
+}
+
+} // namespace
+
+int PrintHost::get_err_code_from_body(const std::string &body)
+{
+    boost::property_tree::ptree root;
+    std::istringstream iss(body);
+    try {
+        boost::property_tree::read_json(iss, root);
+    } catch (const std::exception &ex) {
+        BOOST_LOG_TRIVIAL(error) << "PrintHost: response is not valid JSON: " << ex.what();
+        return -1;
+    }
+
+    return root.get<int>("err", 0);
+}
+
 wxString PrintHost::format_error(const std::string &body, const std::string &error, unsigned status) const
 {
     if (status != 0) {
-        auto wxbody = wxString::FromUTF8(body.data());
+        const std::string reason = moonraker_error_reason(body);
+        auto wxbody = wxString::FromUTF8(reason.empty() ? body : reason);
         return wxString::Format("HTTP %u: %s", status, wxbody);
     } else {
         if (error.find("curl:Timeout was reached") != std::string::npos) {
@@ -245,7 +320,12 @@ void PrintHostJobQueue::priv::bg_thread_main()
                 % job.cancelled;
 
             if (! job.cancelled) {
-                perform_job(std::move(job));
+                // A failing job must not stop the worker, or later jobs would stay queued forever.
+                try {
+                    perform_job(std::move(job));
+                } catch (const std::exception &e) {
+                    emit_error(e.what());
+                }
             }
 
             remove_source();

src/slic3r/Utils/PrintHost.hpp

@@ -87,6 +87,8 @@ public:
 
     static PrintHost* get_print_host(DynamicPrintConfig *config);
     static std::string get_print_host_webui(DynamicPrintConfig *config);
+    // Reads the "err" field of a JSON reply, 0 when absent. Returns -1 when the body is not valid JSON.
+    static int get_err_code_from_body(const std::string &body);
 
     //Support for cloud webui login
     virtual bool is_cloud() const { return false; }

src/slic3r/Utils/UltiMaker.cpp

@@ -654,13 +654,4 @@ bool UltiMaker::start_print(wxString &msg, const std::string &filename, Connecti
 	return res;
 }
 
-int UltiMaker::get_err_code_from_body(const std::string &body) const
-{
-	pt::ptree root;
-	std::istringstream iss (body); // wrap returned json to istringstream
-	pt::read_json(iss, root);
-
-	return root.get<int>("err", 0);
-}
-
 }

src/slic3r/Utils/UltiMaker.hpp

@@ -64,7 +64,6 @@ private:
 	void set_auth(Http& http) const;
 	void disconnect(ConnectionType connectionType) const;
 	bool start_print(wxString &msg, const std::string &filename, ConnectionType connectionType) const;
-	int get_err_code_from_body(const std::string &body) const;
 };
 
 }

tests/fff_print/test_print.cpp

@@ -15,6 +15,9 @@
 #include "libslic3r/Layer.hpp"
 #include "libslic3r/Model.hpp"
 #include "libslic3r/GCodeReader.hpp"
+#include "libslic3r/GCode/GCodeProcessor.hpp"
+#include "libslic3r/Exception.hpp"
+#include "libslic3r/LifecycleEvents.hpp"
 
 #include "test_helpers.hpp"
 #include "test_utils.hpp"
@@ -22,7 +25,10 @@
 #include <algorithm>
 #include <fstream>
 #include <iterator>
+#include <memory>
 #include <string_view>
+#include <utility>
+#include <vector>
 
 using namespace Slic3r;
 using namespace Slic3r::Test;
@@ -224,8 +230,88 @@ std::string resolved_output_name(Model& model, const std::string& format, const
     return print.output_filename(filename_base);
 }
 
+struct ScopedLifecycleHook
+{
+    explicit ScopedLifecycleHook(LifecycleHookFn hook) { set_lifecycle_hook_fn(std::move(hook)); }
+    ~ScopedLifecycleHook() { set_lifecycle_hook_fn(nullptr); }
+};
+
 } // namespace
 
+TEST_CASE("Slicing lifecycle events identify the model", "[Print][LifecycleEvents]")
+{
+    struct ObservedEvent {
+        LifecycleEvent event;
+        std::string id;
+        std::string name;
+    };
+    std::vector<ObservedEvent> events;
+    ScopedLifecycleHook hook([&](LifecycleEvent event, const LifecycleEventContext& ctx) {
+        events.push_back({ event, ctx.id, ctx.name });
+    });
+
+    Print print;
+    Model model;
+    ModelInfo info;
+    info.model_name = "Lifecycle test model";
+    model.model_info = std::make_shared<ModelInfo>(std::move(info));
+    init_print({cube(20)}, print, model);
+
+    print.process();
+    ScopedTemporaryFile temp(".gcode");
+    print.export_gcode(temp.string(), nullptr, nullptr);
+    GCodeProcessorResult result;
+    print.export_gcode_from_previous_file(temp.string(), &result);
+
+    const std::string expected_id = std::to_string(print.model().id().id);
+    const std::vector<LifecycleEvent> expected_events = {
+        LifecycleEvent::SliceStarted,
+        LifecycleEvent::SliceGeometryFinished,
+        LifecycleEvent::GCodeExportStarted,
+        LifecycleEvent::GCodeExportFinished,
+        LifecycleEvent::GCodeExportStarted,
+        LifecycleEvent::GCodeExportFinished,
+    };
+    REQUIRE(events.size() == expected_events.size());
+    for (size_t i = 0; i < expected_events.size(); ++i) {
+        CHECK(events[i].event == expected_events[i]);
+        CHECK(events[i].id == expected_id);
+        CHECK(events[i].name == "Lifecycle test model");
+    }
+}
+
+TEST_CASE("Slicing lifecycle event name is empty without model metadata", "[Print][LifecycleEvents]")
+{
+    std::string event_id;
+    std::string event_name = "unset";
+    ScopedLifecycleHook hook([&](LifecycleEvent event, const LifecycleEventContext& ctx) {
+        if (event == LifecycleEvent::SliceStarted) {
+            event_id = ctx.id;
+            event_name = ctx.name;
+        }
+    });
+
+    Print print;
+    Model model;
+    init_print({cube(20)}, print, model);
+    print.process();
+
+    CHECK(event_id == std::to_string(print.model().id().id));
+    CHECK(event_name.empty());
+}
+
+TEST_CASE("Output filenames with numeric statistics fail before slicing finishes", "[Print][Regression]")
+{
+    DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+    config.set_key_value("filename_format", new ConfigOptionString("{int(total_weight*10) / 10.0}"));
+
+    Print print;
+    Model model;
+    init_print({cube(20)}, print, model, config);
+
+    CHECK_THROWS_AS(print.output_filename(), PlaceholderParserError);
+}
+
 TEST_CASE("Print: {first_object_name} names the first printable object on the plate", "[Print]")
 {
     Model model;

tests/libslic3r/test_3mf.cpp

@@ -17,7 +17,6 @@
 #include <nlohmann/json.hpp>
 
 #include <boost/filesystem/operations.hpp>
-#include <boost/nowide/fstream.hpp>
 #include <boost/algorithm/string/predicate.hpp>
 #include <algorithm>
 
@@ -1462,79 +1461,3 @@ SCENARIO("bbs_3mf_is_published detects only genuinely published 3MFs", "[3mf]")
     }
 }
 
-// Writes a single-entry zip whose central directory carries a zip64 record declaring an
-// uncompressed size beyond what the 32-bit expat buffer API can take, while the deflated
-// payload inflates to only ~64 KiB. Built by hand because miniz never writes a size that
-// disagrees with the data.
-static void write_zip_with_oversized_entry(const std::string& path, const std::string& entry)
-{
-    const std::string xml = "<?xml version=\"1.0\"?><!--" + std::string(65536, 'A') + "--><a/>";
-    size_t comp_len = 0;
-    void*  comp     = tdefl_compress_mem_to_heap(xml.data(), xml.size(), &comp_len, TDEFL_DEFAULT_MAX_PROBES);
-    REQUIRE(comp != nullptr);
-    const std::string deflated(static_cast<const char*>(comp), comp_len);
-    mz_free(comp);
-    const uint32_t crc = static_cast<uint32_t>(mz_crc32(MZ_CRC32_INIT, reinterpret_cast<const unsigned char*>(xml.data()), xml.size()));
-    const uint64_t claimed_size = (uint64_t(1) << 32) + 16;
-
-    std::string out;
-    auto put = [&out](uint64_t v, int bytes) {
-        for (int i = 0; i < bytes; ++i)
-            out.push_back(static_cast<char>((v >> (8 * i)) & 0xFF));
-    };
-    // local file header, with the true sizes
-    put(0x04034b50, 4); put(45, 2); put(0, 2); put(8, 2); put(0, 2); put(0, 2);
-    put(crc, 4); put(deflated.size(), 4); put(xml.size(), 4); put(entry.size(), 2); put(0, 2);
-    out += entry + deflated;
-    // central directory header, sizes deferred to the zip64 extra field
-    const size_t cd_offset = out.size();
-    put(0x02014b50, 4); put(45, 2); put(45, 2); put(0, 2); put(8, 2); put(0, 2); put(0, 2);
-    put(crc, 4); put(0xFFFFFFFF, 4); put(0xFFFFFFFF, 4); put(entry.size(), 2); put(20, 2);
-    put(0, 2); put(0, 2); put(0, 2); put(0, 4); put(0, 4);
-    out += entry;
-    put(0x0001, 2); put(16, 2); put(claimed_size, 8); put(deflated.size(), 8);
-    const size_t cd_size = out.size() - cd_offset;
-    // end of central directory
-    put(0x06054b50, 4); put(0, 2); put(0, 2); put(1, 2); put(1, 2);
-    put(cd_size, 4); put(cd_offset, 4); put(0, 2);
-
-    boost::nowide::ofstream f(path, std::ios::binary);
-    REQUIRE(f.good());
-    f.write(out.data(), static_cast<std::streamsize>(out.size()));
-    REQUIRE(f.good());
-}
-
-TEST_CASE("3MF XML entries declaring more than an int can hold fail to load", "[3mf]") {
-    ScopedTemporaryFile temp(".3mf");
-    const std::string   path = temp.string();
-
-    SECTION("BBS importer") {
-        write_zip_with_oversized_entry(path, "_rels/.rels");
-        Model                     model;
-        DynamicPrintConfig        config;
-        ConfigSubstitutionContext ctxt{ForwardCompatibilitySubstitutionRule::Enable};
-        PlateDataPtrs             plates;
-        std::vector<Preset*>      project_presets;
-        bool                      is_bbl_3mf = false, is_orca_3mf = false;
-        Semver                    file_version;
-        bool                      loaded = true;
-        REQUIRE_NOTHROW(loaded = load_bbs_3mf(path.c_str(), &config, &ctxt, &model, &plates, &project_presets, &is_bbl_3mf,
-                                              &is_orca_3mf, &file_version, nullptr, LoadStrategy::LoadModel | LoadStrategy::LoadConfig));
-        CHECK_FALSE(loaded);
-        release_PlateData_list(plates);
-    }
-    SECTION("PrusaSlicer importer") {
-        write_zip_with_oversized_entry(path, "Metadata/Slic3r_PE_model.config");
-        Model                     model;
-        DynamicPrintConfig        config;
-        ConfigSubstitutionContext ctxt{ForwardCompatibilitySubstitutionRule::Disable};
-        bool                      loaded = true;
-        REQUIRE_NOTHROW(loaded = load_3mf(path.c_str(), config, ctxt, &model, false));
-        CHECK_FALSE(loaded);
-    }
-    SECTION("PrusaSlicer fingerprint probe") {
-        write_zip_with_oversized_entry(path, "3D/3dmodel.model");
-        PrusaFileParser parser;
-        CHECK_FALSE(parser.check_3mf_from_prusa(path));
-    }
-}

tests/slic3rutils/CMakeLists.txt

@@ -18,12 +18,14 @@ add_executable(${_TEST_NAME}_tests
     test_plugin_install.cpp
     test_plugin_lifecycle.cpp
     test_plugin_printer_agent.cpp
+    test_printhost.cpp
     test_slicing_pipeline_bindings.cpp
     test_slicing_pipeline_config.cpp
     test_plugin_sort.cpp
     test_plugin_cloud_metadata.cpp
     test_plugin_audit.cpp
     test_shortcuts.cpp
+    test_user_manager.cpp
     ../fff_print/test_helpers.cpp
     )
 

tests/slic3rutils/test_printhost.cpp

@@ -0,0 +1,316 @@
+#include <catch2/catch_all.hpp>
+
+#include <string>
+#include <vector>
+
+#include <nlohmann/json.hpp>
+
+#include "slic3r/Utils/PrintHost.hpp"
+#include "slic3r/Utils/Flashforge.hpp"
+
+using namespace Slic3r;
+
+namespace {
+
+class TestPrintHost : public PrintHost
+{
+public:
+    using PrintHost::format_error;
+
+    const char* get_name() const override { return "Test"; }
+    bool test(wxString&) const override { return true; }
+    wxString get_test_ok_msg() const override { return {}; }
+    wxString get_test_failed_msg(wxString&) const override { return {}; }
+    bool upload(PrintHostUpload, ProgressFn, ErrorFn, InfoFn) const override { return true; }
+    bool has_auto_discovery() const override { return false; }
+    bool can_test() const override { return false; }
+    PrintHostPostUploadActions get_post_upload_actions() const override { return {}; }
+    std::string get_host() const override { return {}; }
+};
+
+std::string format_error(const std::string& body, const std::string& error, unsigned status)
+{
+    return TestPrintHost().format_error(body, error, status).ToStdString();
+}
+
+std::string envelope(int code, const std::string& message, const std::string& traceback)
+{
+    return nlohmann::json{{"error", {{"code", code}, {"message", message}, {"traceback", traceback}}}}.dump();
+}
+
+std::string moonraker_error(int code, const std::string& message, const std::string& detail = {})
+{
+    std::string line = "tornado.web.HTTPError: HTTP " + std::to_string(code) + ": " + message;
+    if (!detail.empty())
+        line += " (" + detail + ")";
+    return envelope(code, message, "Traceback (most recent call last):\n  ...\n" + line + "\n");
+}
+
+// A real Moonraker body for uploading a file that is being printed.
+constexpr const char* k_busy_file_403 =
+    R"JSON({"error": {"code": 403, "message": "Forbidden", "traceback": "Traceback (most recent call last):\n\n  File \"/home/lava/moonraker/moonraker/components/file_manager/file_manager.py\", line 1017, in _finish_gcode_upload\n    can_start = self._handle_operation_check(check_path)\n                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n\nmoonraker.utils.exceptions.ServerError: File currently in use\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n\n  File \"/home/lava/moonraker/moonraker/components/application.py\", line 1069, in post\n    raise tornado.web.HTTPError(\ntornado.web.HTTPError: HTTP 403: Forbidden (File is loaded, upload not permitted)\n"}})JSON";
+
+// Replies a print host can send instead of JSON: a proxy or login page, nothing, a cut-off body.
+const std::vector<std::string> non_json_replies = {
+    "<html><body>proxy login required</body></html>",
+    "",
+    "{\"err\":",
+    "{\"detail\":{\"matlStationInfo\":{\"slotInfos\":[{\"slotId\":1,",
+};
+
+} // namespace
+
+TEST_CASE("A Klipper upload error shows its reason instead of a Python traceback", "[PrintHost][Regression]")
+{
+    const std::string msg = format_error(k_busy_file_403, "", 403);
+    INFO("actual: " << msg);
+
+    CHECK(msg == "HTTP 403: Forbidden (File is loaded, upload not permitted)");
+    CHECK_THAT(msg, !Catch::Matchers::ContainsSubstring("Traceback"));
+    CHECK_THAT(msg, !Catch::Matchers::ContainsSubstring("file_manager.py"));
+}
+
+TEST_CASE("The specific cause is recovered from a file endpoint's traceback", "[PrintHost]")
+{
+    SECTION("a plain detail")
+    {
+        const std::string body = moonraker_error(403, "Forbidden", "File is loaded, upload not permitted");
+        CHECK(format_error(body, "", 403) == "HTTP 403: Forbidden (File is loaded, upload not permitted)");
+    }
+
+    SECTION("a detail whose own parentheses nest (a filename)")
+    {
+        const std::string detail = "Directory does not exist (/home/pi/gcodes/plate (1).gcode)";
+        const std::string body   = moonraker_error(400, "Bad Request", detail);
+        CHECK(format_error(body, "", 400) == "HTTP 400: Bad Request (" + detail + ")");
+    }
+
+    SECTION("a detail that contains the reason phrase")
+    {
+        const std::string body = moonraker_error(403, "Forbidden", "Forbidden zone: access denied");
+        CHECK(format_error(body, "", 403) == "HTTP 403: Forbidden (Forbidden zone: access denied)");
+    }
+
+    SECTION("a detail that spans lines")
+    {
+        const std::string detail = "Move out of range\nX=250.000 Y=10.000";
+        const std::string body   = moonraker_error(400, "Bad Request", detail);
+        CHECK(format_error(body, "", 400) == "HTTP 400: Bad Request (" + detail + ")");
+    }
+
+    SECTION("a detail that only repeats the reason phrase is dropped")
+    {
+        const std::string body = moonraker_error(401, "Unauthorized", "Unauthorized");
+        CHECK(format_error(body, "", 401) == "HTTP 401: Unauthorized");
+    }
+}
+
+TEST_CASE("An unhandled exception shows its type and message", "[PrintHost]")
+{
+    const std::string frame = "Traceback (most recent call last):\n"
+                              "  File \"/home/pi/moonraker/moonraker/components/file_manager/file_manager.py\", line 1, in write\n"
+                              "    self._write(data)\n";
+
+    SECTION("a one-line message")
+    {
+        const std::string body = envelope(500, "Internal Server Error", frame + "OSError: [Errno 28] No space left on device\n");
+        CHECK(format_error(body, "", 500) == "HTTP 500: Internal Server Error (OSError: [Errno 28] No space left on device)");
+    }
+
+    SECTION("a message that spans lines")
+    {
+        const std::string body = envelope(500, "Internal Server Error", frame + "ServerError: Klippy request failed\n  see klippy.log\n");
+        CHECK(format_error(body, "", 500) == "HTTP 500: Internal Server Error (ServerError: Klippy request failed\n  see klippy.log)");
+    }
+
+    SECTION("raised while handling an HTTPError with the same code")
+    {
+        const std::string traceback = frame + "tornado.web.HTTPError: HTTP 500: Internal Server Error (Database locked)\n\n"
+                                              "During handling of the above exception, another exception occurred:\n\n" +
+                                      frame + "OSError: [Errno 5] Input/output error\n";
+        const std::string body      = envelope(500, "Internal Server Error", traceback);
+        CHECK(format_error(body, "", 500) == "HTTP 500: Internal Server Error (OSError: [Errno 5] Input/output error)");
+    }
+
+    SECTION("a traceback with no header")
+    {
+        const std::string body = envelope(500, "Internal Server Error", "OSError: [Errno 5] Input/output error");
+        CHECK(format_error(body, "", 500) == "HTTP 500: Internal Server Error (OSError: [Errno 5] Input/output error)");
+    }
+}
+
+TEST_CASE("A reason already complete in message is shown unchanged", "[PrintHost]")
+{
+    SECTION("message is the whole reason, no trailing detail")
+    {
+        const std::string body = moonraker_error(503, "Klippy is not ready");
+        CHECK(format_error(body, "", 503) == "HTTP 503: Klippy is not ready");
+    }
+
+    SECTION("a message that itself contains parentheses is not duplicated")
+    {
+        const std::string reason = "Requested blocks (0-5) are unavailable";
+        const std::string body   = moonraker_error(400, reason);
+        CHECK(format_error(body, "", 400) == "HTTP 400: " + reason);
+    }
+}
+
+TEST_CASE("A Moonraker error with no usable detail shows just the reason phrase", "[PrintHost]")
+{
+    struct Case
+    {
+        const char* name;
+        const char* body;
+        unsigned status;
+        const char* expected;
+    };
+
+    const auto c = GENERATE(
+        Case{"an empty traceback", R"JSON({"error": {"code": 500, "message": "Internal Server Error", "traceback": ""}})JSON", 500,
+             "HTTP 500: Internal Server Error"},
+        Case{"a traceback of only whitespace", R"JSON({"error": {"code": 500, "message": "Internal Server Error", "traceback": "\n \n"}})JSON",
+             500, "HTTP 500: Internal Server Error"});
+
+    DYNAMIC_SECTION(c.name) { CHECK(format_error(c.body, "", c.status) == c.expected); }
+}
+
+TEST_CASE("A percent sign in the reason is not a format specifier", "[PrintHost]")
+{
+    const std::string body = moonraker_error(507, "Insufficient Storage", "disk 100% full");
+    CHECK(format_error(body, "", 507) == "HTTP 507: Insufficient Storage (disk 100% full)");
+}
+
+TEST_CASE("Error bodies that are not a Moonraker envelope are left unchanged", "[PrintHost]")
+{
+    SECTION("OctoPrint's string-valued error member")
+    {
+        const std::string body = R"JSON({"error": "File not found"})JSON";
+        CHECK(format_error(body, "", 404) == "HTTP 404: " + body);
+    }
+
+    SECTION("PrusaLink's top-level message, not under error")
+    {
+        const std::string body = R"JSON({"title": "Conflict", "message": "Printer is printing"})JSON";
+        CHECK(format_error(body, "", 409) == "HTTP 409: " + body);
+    }
+
+    SECTION("a body that is not JSON")
+    {
+        const std::string html = "<html><head><title>502 Bad Gateway</title></head></html>";
+        CHECK(format_error(html, "", 502) == "HTTP 502: " + html);
+    }
+
+    SECTION("an error object with no traceback")
+    {
+        const std::string body = R"JSON({"error": {"code": 500, "message": "Internal Server Error"}})JSON";
+        CHECK(format_error(body, "", 500) == "HTTP 500: " + body);
+    }
+
+    SECTION("an error object whose traceback is null")
+    {
+        const std::string body = R"JSON({"error": {"code": 500, "message": "Internal Server Error", "traceback": null}})JSON";
+        CHECK(format_error(body, "", 500) == "HTTP 500: " + body);
+    }
+
+    SECTION("an envelope whose reason phrase is empty")
+    {
+        const std::string body = envelope(403, "", "Traceback (most recent call last):\nOSError: denied\n");
+        CHECK(format_error(body, "", 403) == "HTTP 403: " + body);
+    }
+
+    SECTION("a transport error with no HTTP status")
+    {
+        CHECK(format_error("", "curl:Could not connect", 0) == "curl:Could not connect");
+    }
+}
+
+TEST_CASE("Print host error code is read from a JSON reply", "[PrintHost]")
+{
+    CHECK(PrintHost::get_err_code_from_body(R"({"err":0})") == 0);
+    CHECK(PrintHost::get_err_code_from_body(R"({"err":2})") == 2);
+    CHECK(PrintHost::get_err_code_from_body(R"({"status":"ok"})") == 0);
+}
+
+TEST_CASE("Print host error code reports a reply that is not JSON as an error", "[PrintHost]")
+{
+    const std::string body = GENERATE(from_range(non_json_replies));
+    int err = 0;
+    REQUIRE_NOTHROW(err = PrintHost::get_err_code_from_body(body));
+    CHECK(err != 0);
+}
+
+TEST_CASE("Print host error code tolerates a wrongly typed err field", "[PrintHost]")
+{
+    const std::string body = GENERATE(as<std::string>{}, R"({"err":"busy"})", R"({"err":{"code":1}})", R"([1,2])");
+    CHECK_NOTHROW(PrintHost::get_err_code_from_body(body));
+}
+
+TEST_CASE("Flashforge material slots are read from a well-formed reply", "[PrintHost][Flashforge]")
+{
+    const std::string body = R"({"code":0,"detail":{"hasMatlStation":true,"matlStationInfo":{"slotCnt":2,"slotInfos":[
+        {"slotId":1,"hasFilament":true,"materialName":"PLA","materialColor":"#FFFFFF"},
+        {"slotId":2,"hasFilament":false,"materialName":"","materialColor":""}]}}})";
+
+    std::vector<FlashforgeMaterialSlot> slots;
+    bool supports_station = false;
+    REQUIRE(Flashforge::parse_material_slots(body, slots, &supports_station));
+    CHECK(supports_station);
+    REQUIRE(slots.size() == 2);
+    CHECK(slots[0].slot_id == 1);
+    CHECK(slots[0].has_filament);
+    CHECK(slots[0].material_name == "PLA");
+    CHECK(slots[0].material_color == "#FFFFFF");
+    CHECK(slots[1].slot_id == 2);
+    CHECK_FALSE(slots[1].has_filament);
+}
+
+TEST_CASE("Flashforge material slots accept numbers as strings and flags as numbers", "[PrintHost][Flashforge]")
+{
+    const std::string body = R"({"detail":{"matlStationInfo":{"slotInfos":[
+        {"slotId":"3","hasFilament":1,"materialName":null,"materialColor":7}]}}})";
+
+    std::vector<FlashforgeMaterialSlot> slots;
+    REQUIRE_NOTHROW(Flashforge::parse_material_slots(body, slots, nullptr));
+    REQUIRE(slots.size() == 1);
+    CHECK(slots[0].slot_id == 3);
+    CHECK(slots[0].has_filament);
+    CHECK(slots[0].material_name.empty());
+    CHECK(slots[0].material_color.empty());
+}
+
+TEST_CASE("Flashforge material slots skip entries that are not objects", "[PrintHost][Flashforge]")
+{
+    const std::string body = R"({"detail":{"matlStationInfo":{"slotInfos":[5,"slot",null,[],
+        {"slotId":4,"hasFilament":true,"materialName":"PETG"}]}}})";
+
+    std::vector<FlashforgeMaterialSlot> slots;
+    REQUIRE_NOTHROW(Flashforge::parse_material_slots(body, slots, nullptr));
+    REQUIRE(slots.size() == 1);
+    CHECK(slots[0].slot_id == 4);
+    CHECK(slots[0].material_name == "PETG");
+}
+
+TEST_CASE("Flashforge material slots tolerate slot info that is not a list", "[PrintHost][Flashforge]")
+{
+    const std::string body = GENERATE(as<std::string>{},
+                                      R"({"detail":{"matlStationInfo":{"slotInfos":5}}})",
+                                      R"({"detail":{"matlStationInfo":{"slotInfos":"none"}}})",
+                                      R"({"detail":{"matlStationInfo":7}})",
+                                      R"({"detail":"offline"})");
+
+    std::vector<FlashforgeMaterialSlot> slots;
+    bool ok = false;
+    REQUIRE_NOTHROW(ok = Flashforge::parse_material_slots(body, slots, nullptr));
+    CHECK(ok);
+    CHECK(slots.empty());
+}
+
+TEST_CASE("Flashforge material slots reject a reply that is not JSON", "[PrintHost][Flashforge]")
+{
+    const std::string body = GENERATE(from_range(non_json_replies));
+    std::vector<FlashforgeMaterialSlot> slots;
+    bool ok = true;
+    REQUIRE_NOTHROW(ok = Flashforge::parse_material_slots(body, slots, nullptr));
+    CHECK_FALSE(ok);
+    CHECK(slots.empty());
+}

tests/slic3rutils/test_user_manager.cpp

@@ -0,0 +1,23 @@
+#include <catch2/catch_all.hpp>
+
+#include <string>
+
+#include "slic3r/GUI/UserManager.hpp"
+
+using namespace Slic3r;
+
+TEST_CASE("User message that is not JSON is rejected without throwing", "[UserManager]")
+{
+    const std::string payload = GENERATE(as<std::string>{}, "not json", "", "<html></html>", "{\"bind\":");
+    UserManager manager;
+    int result = 0;
+    REQUIRE_NOTHROW(result = manager.parse_json(payload));
+    CHECK(result == -1);
+}
+
+TEST_CASE("User message without a successful bind is ignored", "[UserManager]")
+{
+    const std::string payload = GENERATE(as<std::string>{}, "{}", R"({"bind":{"command":"unbind"}})", R"({"bind":"bind"})", "[1]");
+    UserManager manager;
+    CHECK(manager.parse_json(payload) == -1);
+}