Makefile changes for Windows and easier development (go-gitea#6103)

* Added Go Path and node_modules to PATH
* Uses npx now for generate-stylesheets
* Uses `go env GOPATH` to calculate adding GOPATH/bin to PATH
* Added note about installing Node 8.0+ to generate stylesheets
* Added preferred Node version to CONTRIBUTING.md

CONTRIBUTING.md

@@ -102,7 +102,7 @@ included in the next released version.
 Generally, the go build tools are installed as-needed in the `Makefile`.
 An exception are the tools to build the CSS and images.
 
-- To build CSS: Install [Node.js](https://nodejs.org/en/download/package-manager)
+- To build CSS: Install [Node.js](https://nodejs.org/en/download/package-manager) at version 8.0 or above
   with `npm` and then run `npm install` and `make generate-stylesheets`.
 - To build Images: ImageMagick, inkscape and zopflipng binaries must be
   available in your `PATH` to run `make generate-images`.

Makefile

@@ -4,6 +4,8 @@ IMPORT := code.gitea.io/gitea
 GO ?= go
 SED_INPLACE := sed -i
 
+export PATH := $($(GO) env GOPATH)/bin:$(PATH)
+
 ifeq ($(OS), Windows_NT)
 	EXECUTABLE := gitea.exe
 else
@@ -365,10 +367,14 @@ stylesheets-check: generate-stylesheets
 
 .PHONY: generate-stylesheets
 generate-stylesheets:
+	@hash npx > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
+		echo "Please install npm version 5.2+"; \
+		exit 1; \
+	fi;
 	$(eval BROWSERS := "> 2%, last 2 firefox versions, last 2 safari versions")
-	node_modules/.bin/lessc --clean-css public/less/index.less public/css/index.css
-	$(foreach file, $(filter-out public/less/themes/_base.less, $(wildcard public/less/themes/*)),node_modules/.bin/lessc --clean-css public/less/themes/$(notdir $(file)) > public/css/theme-$(notdir $(call strip-suffix,$(file))).css;)
-	$(foreach file, $(wildcard public/css/*),node_modules/.bin/postcss --use autoprefixer --autoprefixer.browsers $(BROWSERS) -o $(file) $(file);)
+	npx lessc --clean-css public/less/index.less public/css/index.css
+	$(foreach file, $(filter-out public/less/themes/_base.less, $(wildcard public/less/themes/*)),npx lessc --clean-css public/less/themes/$(notdir $(file)) > public/css/theme-$(notdir $(call strip-suffix,$(file))).css;)
+	$(foreach file, $(wildcard public/css/*),npx postcss --use autoprefixer --autoprefixer.browsers $(BROWSERS) -o $(file) $(file);)
 
 .PHONY: swagger-ui
 swagger-ui:

docs/content/doc/advanced/hacking-on-gitea.en-us.md

@@ -138,6 +138,8 @@ make vet lint misspell-check
 
 ### Updating the stylesheets
 
+To generate the stylsheets, you will need [Node.js](https://nodejs.org/) at version 8.0 or above.
+
 At present we use [less](http://lesscss.org/) and [postcss](https://postcss.org) to generate our stylesheets. Do
 **not** edit the files in `public/css/` directly as they are generated from
 `lessc` from the files in `public/less/`.