Express.js在Docker容器内找不到模块'opencv'

Question

I am trying to install the OpenCV bindings for NODE so that I can use AI with my express server. I am using the Peter Braden Library - https://github.com/peterbraden/node-opencv .

However, I keep getting a repeated issue when spinning up the docker container which states:

express_1  | Error: Cannot find module 'opencv'
express_1  |     at Function.Module._resolveFilename (module.js:485:15)
express_1  |     at Function.Module._load (module.js:437:25)
express_1  |     at Module.require (module.js:513:17)
express_1  |     at require (internal/module.js:11:18)
express_1  |     at Object.<anonymous> (/myapp/routes/OpenCV.js:3:10)
express_1  |     at Module._compile (module.js:569:30)
express_1  |     at Object.Module._extensions..js (module.js:580:10)
express_1  |     at Module.load (module.js:503:32)
express_1  |     at tryModuleLoad (module.js:466:12)
express_1  |     at Function.Module._load (module.js:458:3)
express_1  |     at Module.require (module.js:513:17)
express_1  |     at require (internal/module.js:11:18)
express_1  |     at Object.<anonymous> (/myapp/app.js:69:16)
express_1  |     at Module._compile (module.js:569:30)
express_1  |     at Object.Module._extensions..js (module.js:580:10)
express_1  |     at Module.load (module.js:503:32)
express_1  | npm info lifecycle backend@0.0.0~start: Failed to exec     start script
express_1  | npm ERR! code ELIFECYCLE
express_1  | npm ERR! errno 1
express_1  | npm ERR! backend@0.0.0 start: `node ./bin/www`
express_1  | npm ERR! Exit status 1
express_1  | npm ERR! 
express_1  | npm ERR! Failed at the backend@0.0.0 start script.
express_1  | npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
express_1  | 
express_1  | npm ERR! A complete log of this run can be found in:
express_1  | npm ERR!     /root/.npm/_logs/2017-10-25T15_32_12_258Z-debug.log
maya_express_1 exited with code 1

I have tried accessing the container and using bash within to install open cv but this does not work either.

I am running on Sierra 10.12.6

If I delete node_modules and then run -

docker run -v $(pwd):/myapp express-dev:1.0.0 npm install

it throws me a completely different error

 gyp info spawn args   '-Goutput_dir=.' ]
 /myapp/node_modules/opencv/utils/find-opencv.js:21
                 throw new Error("ERROR: failed to run: pkg-config", opencv, flag);
            ^

 Error: ERROR: failed to run: pkg-config
     at /myapp/node_modules/opencv/utils/find-opencv.js:21:23
     at ChildProcess.exithandler (child_process.js:277:5)
     at emitTwo (events.js:125:13)
     at ChildProcess.emit (events.js:213:7)
     at maybeClose (internal/child_process.js:921:16)
     at Socket.stream.socket.on (internal/child_process.js:348:11)
     at emitOne (events.js:115:13)
     at Socket.emit (events.js:210:7)
     at Pipe._handle.close [as _onclose] (net.js:549:12)
 gyp: Call to 'node utils/find-opencv.js --cflags' returned exit status 1 while in binding.gyp. while trying to load binding.gyp

I have tried relinking opencv and using opencv@2 as well with no luck.

My Dockerfile:

# Based off: https://hub.docker.com/r/danlynn/ember-cli/
# See ./provisioning/containers for more.

FROM node:8.2.1
MAINTAINER thestartupfactory.tech <hello@thestartupfactory.tech>
ENV WORKDIR=/opt NODE_ENV=production

# express server on 3000
# ember will be compiled and served via express
EXPOSE 3000
# Use /opt for building container
WORKDIR $WORKDIR

# See WORKDIR command at end of file
CMD ["npm", "start"]

# Update the image
# Install ember dev dependencies
# Install ember-cli and express-generator
RUN \
    apt-get update -y && \
    npm install -g bower@1.8.0 &&\
    npm install -g ember-cli@2.14.2 &&\
    npm install -g express-generator@4.15.0

# Import the code
RUN \
    mkdir -p /opt/ember && \
    mkdir -p /opt/express

COPY ./frontend/ /opt/ember/
COPY ./backend/ /opt/express/

# Run npm install
# Compile ember, insert to express && delete ember source
# Cleanup caches
RUN \
    cd /opt/ember && npm install &&\
    ember build --environment production && mv dist/ ../express/ &&\
    cd .. && rm -rf ember &&\
    cd /opt/express && npm install && cd .. &&\
    apt-get clean &&\
    apt-get autoremove --purge

# Move the WORKDIR ready for entrypoint
WORKDIR $WORKDIR/express

Any help would be greatly appreciated! Thanks in advance

Answer 1

Looks like you did not even set up node-opencv in your docker image. There is a difference between setting up node-opencv on your local machine and in your docker image. In your Dockerfile you have to include the commands to setup opencv and node-opencv. You can refer to the OpenCV travis.yml if you are unsure how to setup OpenCV in a Linux environment.

Alternatively you can have a look at opencv-express . It is an example of how to use opencv with nodejs and express. It uses opencv4nodejs however. You can also just pull one of the provided base images, depending on the OpenCV version you want to use and install your node environment with node-opencv on top.