Add fileToString utility function

Author: Levi-Armstrong

tesseract_common/include/tesseract_common/utils.h

@@ -67,6 +67,13 @@ std::string strFormat(const std::string& format, Args... args)
   return std::string{ buf.get(), buf.get() + size - 1 };  // We don't want the '\0' inside
 }
 
+/**
+ * @brief Read in the contents of the file into a string
+ * @param filepath The file to read
+ * @return The contents of the file
+ */
+std::string fileToString(const tesseract_common::fs::path& filepath);
+
 /**
  * @brief Change the reference point of the provided Twist
  * @param twist The current Twist which gets modified in place

tesseract_common/src/utils.cpp

@@ -30,6 +30,7 @@ TESSERACT_COMMON_IGNORE_WARNINGS_PUSH
 #include <string>
 #include <type_traits>
 #include <console_bridge/console.h>
+#include <fstream>
 TESSERACT_COMMON_IGNORE_WARNINGS_POP
 
 #include <tesseract_common/utils.h>
@@ -68,6 +69,20 @@ std::enable_if_t<std::is_polymorphic<E>::value> my_rethrow_if_nested(const E& e)
     p->rethrow_nested();
 }
 
+std::string fileToString(const tesseract_common::fs::path& filepath)
+{
+  std::ifstream ifs(filepath.c_str());
+  std::string contents;
+
+  ifs.seekg(0, std::ios::end);
+  contents.reserve(ifs.tellg());
+  ifs.seekg(0, std::ios::beg);
+
+  contents.assign(std::istreambuf_iterator<char>(ifs), std::istreambuf_iterator<char>());
+  ifs.close();
+  return contents;
+}
+
 // LCOV_EXCL_START
 // These are tested in both tesseract_kinematics and tesseract_state_solver
 void twistChangeRefPoint(Eigen::Ref<Eigen::VectorXd> twist, const Eigen::Ref<const Eigen::Vector3d>& ref_point)