Add make target python-requirements to install Python requirements of project

.travis.yml

@@ -19,6 +19,7 @@ jobs:
         - python3-sphinx
         - python3-pip
         - python3-setuptools
+        - python3-cairocffi
         - graphviz-dev
         - xmlstarlet
         - jq

.travis/build.sh

@@ -75,6 +75,7 @@ if [ "$TRAVIS_BUILD_STAGE_NAME" == "Test" ]; then
 	unset SMING_PROJECTS_DIR
 	make docs V=1
 else
+	make -C "$SMING_PROJECTS_DIR/samples/HttpServer_FirmwareUpload" python-requirements PIP_ARGS=--user
 	$MAKE_PARALLEL samples
 	make clean samples-clean
 	$MAKE_PARALLEL Basic_Blink ENABLE_CUSTOM_HEAP=1 DEBUG_VERBOSE_LEVEL=3

.travis/install.sh

@@ -1,11 +1,10 @@
 #!/bin/bash
 set -ex # exit with nonzero exit code if anything fails
 
-pip install --user -r $TRAVIS_BUILD_DIR/samples/HttpServer_FirmwareUpload/requirements.txt
-
 if [ "$TRAVIS_BUILD_STAGE_NAME" == "Test" ]; then
 	sudo update-alternatives --install /usr/bin/clang-format clang-format /usr/bin/clang-format-6.0 100
-	pip3 install -r $TRAVIS_BUILD_DIR/docs/requirements.txt
+	python3 -m pip install --upgrade pip
+	python3 -m pip install -r $TRAVIS_BUILD_DIR/docs/requirements.txt
 fi
 
 if [ "$SMING_ARCH" == "Esp8266" ]; then

Sming/Components/terminal/README.rst

@@ -9,9 +9,9 @@ Introduction
 This Component provides make targets to support a serial terminal for communicating with devices.
 
 The default serial terminal is `miniterm <https://pyserial.readthedocs.io/en/latest/tools.html#module-serial.tools.miniterm>`__.
-If you don't have it installed already, do this::
+If you don't have it installed already, you can install it via pip using the following command::
 
-   pip install pyserial
+   make python-requirements
 
 (You'll need `python <https://www.python.org/>`__, of course.)
 

Sming/Components/terminal/requirements.txt

@@ -0,0 +1 @@
+pyserial

Sming/building.rst

@@ -562,6 +562,22 @@ changed as required.
 
    Set to any additional flags to be used when linking.
 
+.. envvar:: COMPONENT_PYTHON_REQUIREMENTS
+
+   If the component requires uncommon Python modules (e. g. as part of a custom
+   build step), set this variable to one or more `requirements.txt <https://pip.readthedocs.io/en/latest/reference/pip_install/#requirements-file-format>`_
+   files. This allows installation of all python requirements of the project by
+   invoking::
+
+      make python-requirements [PIP_ARGS=...]
+
+   .. note::
+
+      A `requirements.txt` file in the root directory of the Component is
+      detected automatically without setting this variable. To prevent
+      autodetection (e.g. if the python requirements depend on another
+      configuration variable) you must set this variable to an empty value.
+
 These values are global so must only be appended to (with ``+=``) ,
 never overwritten.
 

Sming/project.mk

@@ -137,6 +137,9 @@ COMPONENTS_EXTRA_INCDIR	:=
 # Components may specify directories containing source code to be compiled with application
 APPCODE				:=
 
+# Python requirements.txt collected from components
+PYTHON_REQUIREMENTS := 
+
 #
 # This macro sets the default component variables before including the (optional) component.mk file.
 #
@@ -160,6 +163,7 @@ COMPONENT_VARS			:=
 COMPONENT_RELINK_VARS	:=
 COMPONENT_TARGETS		:=
 COMPONENT_DEPENDS		:=
+COMPONENT_PYTHON_REQUIREMENTS		:= $$(wildcard $2/requirements.txt)
 EXTRA_LIBS				:=
 EXTRA_LDFLAGS			:=
 # Process any component.mk file (optional)
@@ -184,6 +188,7 @@ CMP_$1_LIBNAME			:= $$(COMPONENT_LIBNAME)
 CMP_$1_INCDIRS			:= $$(COMPONENT_INCDIRS)
 CMP_$1_DEPENDS			:= $$(COMPONENT_DEPENDS)
 CMP_$1_RELINK_VARS		:= $$(COMPONENT_RELINK_VARS)
+PYTHON_REQUIREMENTS		+= $$(call AbsoluteSourcePath,$2,$$(COMPONENT_PYTHON_REQUIREMENTS))
 APPCODE					+= $$(call AbsoluteSourcePath,$2,$$(CMP_$1_APPCODE))
 COMPONENTS				+= $$(filter-out $$(COMPONENTS),$$(CMP_$1_DEPENDS))
 ifneq (App,$1)
@@ -450,6 +455,17 @@ decode-stacktrace: ##Open the stack trace decoder ready to paste dump text. Alte
 	$(Q) $(PYTHON) $(ARCH_TOOLS)/decode-stacktrace.py $(TARGET_OUT_0) $(TRACE)
 
 
+CACHE_VARS += PIP_ARGS
+PIP_ARGS ?=
+.PHONY: python-requirements
+python-requirements: ##Install Python requirements of project via pip (use PIP_ARGS=... for additional options)
+ifeq (,$(PYTHON_REQUIREMENTS))
+	@echo No Python requirements to install for this project.
+else
+	@echo Installing Python requirements...
+	$(Q) $(PYTHON) -m pip install $(PIP_ARGS) $(foreach reqfile,$(PYTHON_REQUIREMENTS),-r $(reqfile))
+endif
+
 ##@Testing
 
 # OTA Server
@@ -505,6 +521,21 @@ list-components: ##Print details of all Components for this project
 	$(info Components:)
 	$(foreach c,$(sort $(COMPONENTS)),$(eval $(call PrintComponentInfo,$c)))
 
+# Dump content of requirements.txt file
+# $1 -> absolute path to file
+define DumpRequirementsTxt
+	@echo \# From $1:
+	@cat $1
+
+endef
+.PHONY: list-python-requirements
+list-python-requirements: ##List Python requirements for this project
+ifeq (,$(PYTHON_REQUIREMENTS))
+	@echo \# No Python requirements for this project.
+else
+	$(foreach reqfile,$(PYTHON_REQUIREMENTS),$(call DumpRequirementsTxt,$(reqfile)))
+endif
+
 # => Help
 .PHONY: help
 help: ##Show this help summary
@@ -516,7 +547,7 @@ ifneq (,$V)
 	@echo '  cmp-rebuild'
 endif
 
-	
+
 # Update build type cache
 $(shell	mkdir -p $(dir $(BUILD_TYPE_FILE)); \
 		echo '# Automatically generated file. Do not edit.' > $(BUILD_TYPE_FILE); \

samples/HttpServer_FirmwareUpload/component.mk

@@ -9,10 +9,6 @@ web-pack:
 web-upload: web-pack spiffs-image-update
 	$(call WriteFlash,$(RBOOT_SPIFFS_0)=$(SPIFF_BIN_OUT))
 
-.PHONY: python-requirements
-python-requirements:
-	$(PYTHON) -m pip install --user -r requirements.txt
-
 SIGNTOOL := $(PYTHON) $(COMPONENT_PATH)/signtool.py
 SIGNING_KEY := $(COMPONENT_PATH)/signing.key
 VERIFICATION_HEADER := $(COMPONENT_PATH)/app/FirmwareVerificationKey.h

samples/HttpServer_FirmwareUpload/requirements.txt

@@ -1,3 +1 @@
-# Requirements file for pip
-# list of Python packages used in documentation build
 PyNaCl