how to get docker container to read from stdin?

Question

I have a script that I want to use to use Sigil (based on Go's template engine) to populate template files

I'm using a dockerized sigil for this via:

docker run -v ${TEMPLATE_DIR}:/tmp/sigil mikegrass/gliderlabs_sigil-docker/sigil -f prometheus-configmap.yaml -p API_SERVER=$api_server_url > $TEMP_FILE

This seems a bit clunky with having to map a volume, so I'd rather use STDIN to pass in the file....

So what I'd like is

cat ./prometheus-configmap.yaml | docker run mikegrass/gliderlabs_sigil-docker -p API_SERVER=$api_server_url > $TEMP_FILE

Unfortunately this doesn't work, I get no output.

Googling around I see possible solutions but haven't gotten any to work...

score 35 · Accepted Answer · answered Jun 07 '17 at 19:59

35

You need to run the container in interactive mode with --interactive or -i:

cat ./prometheus-configmap.yaml | docker run -i mikegrass/gliderlabs_sigil-docker -p API_SERVER=$api_server_url > $TEMP_FILE

answered Jun 07 '17 at 19:59

Andy Shinn

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[`docker run` options](https://docs.docker.com/engine/reference/commandline/run/#options) – Matt Nov 16 '17 at 22:06

score 2 · Answer 2 · answered Mar 19 '21 at 19:19

2

Without cat:

docker run -i mikegrass/gliderlabs_sigil-docker -p API_SERVER=$api_server_url < ./prometheus-configmap.yaml

answered Mar 19 '21 at 19:19

rouble

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how to get docker container to read from stdin?

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