Add example/docker (refs #173) (#174)

README.md

@@ -22,6 +22,10 @@ gopkg.in/gographics/imagick.v1/imagick
 
 # Install
 
+## Docker
+
+See [examples/docker](examples/docker)
+
 ## Mac OS X
 
 ### MacPorts

examples/docker/Dockerfile

@@ -0,0 +1,33 @@
+FROM golang:1.11
+
+# Ignore APT warnings about not having a TTY
+ENV DEBIAN_FRONTEND noninteractive
+
+# install build essentials
+RUN apt-get update && \
+    apt-get install -y wget build-essential pkg-config --no-install-recommends
+
+# Install ImageMagick deps
+RUN apt-get -q -y install libjpeg-dev libpng-dev libtiff-dev \
+    libgif-dev libx11-dev --no-install-recommends
+
+ENV IMAGEMAGICK_VERSION=6.9.10-11
+
+RUN cd && \
+	wget https://github.com/ImageMagick/ImageMagick6/archive/${IMAGEMAGICK_VERSION}.tar.gz && \
+	tar xvzf ${IMAGEMAGICK_VERSION}.tar.gz && \
+	cd ImageMagick* && \
+	./configure \
+	    --without-magick-plus-plus \
+	    --without-perl \
+	    --disable-openmp \
+	    --with-gvc=no \
+	    --disable-docs && \
+	make -j$(nproc) && make install && \
+	ldconfig /usr/local/lib
+
+WORKDIR /go/projects/resizer
+COPY . .
+
+RUN go install
+CMD /go/bin/resizer

examples/docker/go.mod

@@ -0,0 +1,4 @@
+module resizer
+
+require gopkg.in/gographics/imagick.v2 v2.5.0
+

examples/docker/main.go

@@ -0,0 +1,50 @@
+// Port of http://members.shaw.ca/el.supremo/MagickWand/resize.htm to Go
+package main
+
+import (
+	"fmt"
+
+	"gopkg.in/gographics/imagick.v2/imagick"
+)
+
+func main() {
+	imagick.Initialize()
+	// Schedule cleanup
+	defer imagick.Terminate()
+	var err error
+
+	mw := imagick.NewMagickWand()
+
+	err = mw.ReadImage("logo:")
+	if err != nil {
+		panic(err)
+	}
+
+	// Get original logo size
+	width := mw.GetImageWidth()
+	height := mw.GetImageHeight()
+
+	// Calculate half the size
+	hWidth := uint(width / 2)
+	hHeight := uint(height / 2)
+
+	// Resize the image using the Lanczos filter
+	// The blur factor is a float, where > 1 is blurry, < 1 is sharp
+	err = mw.ResizeImage(hWidth, hHeight, imagick.FILTER_LANCZOS, 1)
+	if err != nil {
+		panic(err)
+	}
+
+	// Set the compression quality to 95 (high quality = low compression)
+	err = mw.SetImageCompressionQuality(95)
+	if err != nil {
+		panic(err)
+	}
+
+	out := "/tmp/out.png"
+	if err = mw.WriteImage(out); err != nil {
+		panic(err)
+	}
+
+	fmt.Printf("Wrote: %s\n", out)
+}