Parse requirements.txt in CMake

Author: multiplemonomials

tools/cmake/app.cmake

@@ -20,15 +20,39 @@ include(${MBED_PATH}/tools/cmake/profile.cmake)
 
 enable_language(C CXX ASM)
 
-# Find Python and needed packages
-find_package(Python3)
+# Find Python
+find_package(Python3 COMPONENTS Interpreter)
 include(${CMAKE_CURRENT_LIST_DIR}/CheckPythonPackage.cmake)
-check_python_package(intelhex HAVE_INTELHEX)
-check_python_package(prettytable HAVE_PRETTYTABLE)
 
-if(Python3_FOUND AND HAVE_INTELHEX AND HAVE_PRETTYTABLE)
+# Check python packages from requirements.txt
+file(STRINGS ${CMAKE_CURRENT_LIST_DIR}/requirements.txt PYTHON_REQUIREMENTS)
+foreach(REQUIREMENT ${PYTHON_REQUIREMENTS})
+	
+	# Look for a string from the start of each line that does not contain "<", ">", "=", or " ".
+	if(REQUIREMENT MATCHES "^([^<>= ]+)")
+
+		set(PACKAGE_NAME ${CMAKE_MATCH_1})
+		string(TOUPPER ${PACKAGE_NAME} PACKAGE_NAME_UCASE) # Ucase name needed for CMake variable
+		string(TOLOWER ${PACKAGE_NAME} PACKAGE_NAME_LCASE) # Lcase name needed for import statement
+
+		check_python_package(${PACKAGE_NAME_LCASE} HAVE_PYTHON_${PACKAGE_NAME_UCASE})
+		if(NOT HAVE_PYTHON_${PACKAGE_NAME_UCASE})
+			message(WARNING "Missing Python dependency ${PACKAGE_NAME}")
+		endif()
+
+	else()
+
+		message(FATAL_ERROR "Cannot parse line \"${REQUIREMENT}\" in requirements.txt")
+
+	endif()
+
+endforeach()
+
+# Check deps for memap
+if(Python3_FOUND AND HAVE_PYTHON_INTELHEX AND HAVE_PYTHON_PRETTYTABLE)
 	set(HAVE_MEMAP_DEPS TRUE)
 else()
 	set(HAVE_MEMAP_DEPS FALSE)
 	message(STATUS "Missing Python dependencies (python3, intelhex, prettytable) so the memory map cannot be printed")
-endif()
+endif()
+