Add missing files in exception message (#5360)

CHANGELOG.md

@@ -4,6 +4,7 @@
       - FIXED: Use Boost.Beast to parse HTTP request. [#6294](https://github.com/Project-OSRM/osrm-backend/pull/6294)
       - FIXED: Fix inefficient osrm-routed connection handling [#6113](https://github.com/Project-OSRM/osrm-backend/pull/6113)
     - Misc:
+      - CHANGED: missing files list is included in exception message. [#5360](https://github.com/Project-OSRM/osrm-backend/pull/5360)
       - CHANGED: Do not use deprecated Callback::Call overload in Node bindings. [#6318](https://github.com/Project-OSRM/osrm-backend/pull/6318)
       - FIXED: Fix distance calculation consistency. [#6315](https://github.com/Project-OSRM/osrm-backend/pull/6315)
       - FIXED: Fix performance issue after migration to sol2 3.3.0. [#6304](https://github.com/Project-OSRM/osrm-backend/pull/6304)

include/storage/io_config.hpp

@@ -25,6 +25,7 @@ struct IOConfig
     }
 
     bool IsValid() const;
+    std::vector<std::string> GetMissingFiles() const;
     boost::filesystem::path GetPath(const std::string &fileName) const
     {
         if (!IsConfigured(fileName, required_input_files) &&

src/osrm/osrm.cpp

@@ -10,6 +10,8 @@
 #include "engine/engine_config.hpp"
 #include "engine/status.hpp"
 
+#include <boost/algorithm/string/join.hpp>
+
 #include <memory>
 
 namespace osrm
@@ -25,8 +27,11 @@ OSRM::OSRM(engine::EngineConfig &config)
     // First, check that necessary core data is available
     if (!config.use_shared_memory && !config.storage_config.IsValid())
     {
-        throw util::exception("Required files are missing, cannot continue.  Have all the "
+        const auto &missingFiles = config.storage_config.GetMissingFiles();
-                              "pre-processing steps been run?");
+        throw util::exception("Required files are missing, cannot continue. Have all the "
+                              "pre-processing steps been run? "
+                              "Missing files: " +
+                              boost::algorithm::join(missingFiles, ", "));
     }
 
     // Now, check that the algorithm requested can be used with the data

src/storage/io_config.cpp

@@ -10,10 +10,11 @@ namespace osrm
 {
 namespace storage
 {
+
+namespace fs = boost::filesystem;
+
 bool IOConfig::IsValid() const
 {
-    namespace fs = boost::filesystem;
-
     bool success = true;
     for (auto &fileName : required_input_files)
     {
@@ -26,5 +27,18 @@ bool IOConfig::IsValid() const
     }
     return success;
 }
+
+std::vector<std::string> IOConfig::GetMissingFiles() const
+{
+    std::vector<std::string> missingFiles;
+    for (auto &fileName : required_input_files)
+    {
+        if (!fs::is_regular_file(fs::path(base_path.string() + fileName.string())))
+        {
+            missingFiles.push_back(base_path.string() + fileName.string());
+        }
+    }
+    return missingFiles;
+}
 } // namespace storage
 } // namespace osrm