how to run chromedp in docker - docker

Question

I am trying to run chromedp in docker.
My main.go:
package main
import (
"context"
"log"
"time"
"github.com/chromedp/chromedp"
)
func main() {
log.SetFlags(log.LstdFlags | log.Llongfile)
ctx, cancel := chromedp.NewContext(
context.Background(),
chromedp.WithLogf(log.Printf),
)
defer cancel()
// create a timeout
ctx, cancel = context.WithTimeout(ctx, 15 * time.Second)
defer cancel()
u := `https://www.whatismybrowser.com/detect/what-is-my-user-agent`
selector := `#detected_value`
log.Println("requesting", u)
log.Println("selector", selector)
var result string
err := chromedp.Run(ctx,
chromedp.Navigate(u),
chromedp.WaitReady(selector),
chromedp.OuterHTML(selector, &result),
)
if err != nil {
log.Fatal(err)
}
log.Printf("result:\n%s", result)
}
Dockerfile:
FROM golang:latest as build-env
RUN mkdir $GOPATH/src/app
WORKDIR $GOPATH/src/app
ENV GO111MODULE=on
COPY go.mod .
COPY go.sum .
COPY main.go .
RUN go mod download
RUN go build -o /root/app
FROM chromedp/headless-shell
COPY --from=build-env /root/app /
CMD ["/app"]
When I run it:
docker-compose build
docker-compose up
It outputs:
app_1 | [1129/192523.576726:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
app_1 | [1129/192523.602779:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
app_1 |
app_1 | DevTools listening on ws://0.0.0.0:9222/devtools/browser/3fa247e0-e2fa-484e-8b5f-172b392701bb
app_1 | [1129/192523.836854:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
app_1 | [1129/192523.838804:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
app_1 | [1129/192523.845866:ERROR:egl_util.cc(60)] Failed to load GLES library: /headless-shell/swiftshader/libGLESv2.so: /headless-shell/swiftshader/libGLESv2.so: cannot open shared object file: No such file or directory
app_1 | [1129/192523.871796:ERROR:viz_main_impl.cc(176)] Exiting GPU process due to errors during initialization
app_1 | [1129/192523.897083:WARNING:gpu_process_host.cc(1220)] The GPU process has crashed 1 time(s)
app_1 | [1129/192523.926741:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
app_1 | [1129/192523.930111:ERROR:egl_util.cc(60)] Failed to load GLES library: /headless-shell/swiftshader/libGLESv2.so: /headless-shell/swiftshader/libGLESv2.so: cannot open shared object file: No such file or directory
app_1 | [1129/192523.943794:ERROR:viz_main_impl.cc(176)] Exiting GPU process due to errors during initialization
app_1 | [1129/192523.948757:WARNING:gpu_process_host.cc(1220)] The GPU process has crashed 2 time(s)
app_1 | [1129/192523.950107:ERROR:browser_gpu_channel_host_factory.cc(138)] Failed to launch GPU process.
app_1 | [1129/192524.013014:ERROR:browser_gpu_channel_host_factory.cc(138)] Failed to launch GPU process.
So it doesn't run my go app. I expect that chromedp/headless-shell contains google-chrome and my golang app would successfully use it over github.com/chromedp/chromedp
Update 1
I added missing directories:
RUN mkdir -p /headless-shell/swiftshader/ \
&& cd /headless-shell/swiftshader/ \
&& ln -s ../libEGL.so libEGL.so \
&& ln -s ../libGLESv2.so libGLESv2.so
and now have the following output, my app still not running:
app_1 | [1202/071210.095414:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
app_1 | [1202/071210.112632:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
app_1 |
app_1 | DevTools listening on ws://0.0.0.0:9222/devtools/browser/86e31db1-3a17-4da6-9e2f-696647572492
app_1 | [1202/071210.166158:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
app_1 | [1202/071210.186307:WARNING:resource_bundle.cc(426)] locale_file_path.empty() for locale
Update 2
Looks like CMD ["/app"] doesn't run my main.go file because it doesn't print any lines from it.
And when I run it manually:
$ /usr/local/bin/docker exec -ti chromedp_docker_app_1 /bin/bash
root#0c417fd159a2:/# /app
2019/12/02 07:40:34 app is running
2019/12/02 07:40:34 /go/src/app/main.go:26: requesting https://www.whatismybrowser.com/detect/what-is-my-user-agent
2019/12/02 07:40:34 /go/src/app/main.go:27: selector #detected_value
2019/12/02 07:40:34 /go/src/app/main.go:35: exec: "google-chrome": executable file not found in $PATH
I see that google-chrome app is still not there, hmmm....

Answer 1

You are missing few things here, First you need to run google-headless-chrome inside your container. you can use following Dockerfile
FROM golang:1.12.0-alpine3.9
RUN apk update && apk upgrade && apk add --no-cache bash git && apk add --no-cache chromium
# Installs latest Chromium package.
RUN echo #edge http://nl.alpinelinux.org/alpine/edge/community >> /etc/apk/repositories \
&& echo #edge http://nl.alpinelinux.org/alpine/edge/main >> /etc/apk/repositories \
&& apk add --no-cache \
harfbuzz#edge \
nss#edge \
freetype#edge \
ttf-freefont#edge \
&& rm -rf /var/cache/* \
&& mkdir /var/cache/apk
RUN go get github.com/mafredri/cdp
CMD chromium-browser --headless --disable-gpu --remote-debugging-port=9222 --disable-web-security --safebrowsing-disable-auto-update --disable-sync --disable-default-apps --hide-scrollbars --metrics-recording-only --mute-audio --no-first-run --no-sandbox
I am using CDP, More robust and fun for me!
This is the link for CDP: https://github.com/mafredri/cdp

Answer 2

Is not pretty but here is a simple docker that worked for me
FROM golang:1.16.5 AS build-env
RUN apt update && apt -y upgrade
RUN apt -y install chromium
WORKDIR /app
ADD ./ ./
RUN go mod download
RUN go build -o /docker-gs-ping
CMD [ "/docker-gs-ping" ]