v.in.ogr does not provide any error information

Question

I am using the mundialis/grass-py3-pdal:8.2.0-alpine docker image to run GRASS. I run the following from the bash command line (inside the container):

/usr/local/grass/bin/v.in.ogr input=/path/to/nonexistent/folder/and/file.shp output=/another/nonexistent/path

... and I get back no output. The script just runs and finishes. No complaint. Nothing.

So I try it in verbose mode, with an existing output folder:

/usr/local/grass/bin/v.in.ogr --verbose input=/path/to/nonexistent/folder/and/file.shp output=/output

Still no complaint. Needless to say, there's also nothing in the output folder.

What's going on here? Is there a way I can get the script to give me more information? As I've never used this script, I'm sort of hoping to have some google-able error messages if possible.

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EDIT #1: I verified that when I do ls /usr/local/grass/bin/v.in.ogr from inside the container, I get a listing of the script, which is shown in a nice, executable green font. So the script seems to be running. It's just being very, very quiet when things go wrong.

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EDIT #2: I also verified with a touch that I have the rights to write to the output folder. So it's not that.

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EDIT #3: I simplified the situation above somewhat to make the question easier to answer. The full command for running the script with a real file is docker-compose run --rm grass-service /usr/local/grass/bin/v.in.ogr --verbose input=/input/kx-amtrak-stations-SHP/amtrak-stations.shp output=/output/grass_map. This is also failing silently, though I get a status of 0 rather than a status of 1. The output folder is set to rw in my docker-compose.yml file, which looks like this:

version: '3'
services:
  grass-service:
    image: mundialis/grass-py3-pdal:8.2.0-alpine
    volumes:
      - ./output:/output:rw # This will be the persistent store
      - ./src:/src:rw # Contains code to run analysis
      - ./input:/input # Contains some .tif images to import
    environment:
      - STAGE=dev
      - GISDBASE=/data/grassdata
      - LOCATION=2193
      - MAPSET=project
      - LC_ALL=C.UTF-8
      - LANG=C.UTF-8
      - ADDITIONAL_PATH=/usr/local/grass/bin
    network_mode: host
    stdin_open: true
    tty: true

... and the Dockerfile looks like this:

FROM mundialis/grass-py3-pdal:8.2.0-alpine
RUN export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/local/grass/bin
RUN chmod +x /src/fulltask.sh
RUN chmod +w /output

Answer 1

Before you can import a file using v.in.ogr you first have to create a GRASS environment: a database, location, and mapset. I use this same Docker container (in conjunction with some workflow software) and I precede the import statement with grass -c {file} -e {grass-database}:

GRASSDATA=/output/grassdata && \
MAPSET=PERMANENT && \
MAP=amtrak-stations && \
mkdir -p $GRASSDATA && \
(grass -c /input/kx-amtrak-stations-SHP/amtrak-stations.shp -e $GRASSDATA && \
grass $GRASSDATA/$MAPSET/ --exec v.in.ogr --verbose --overwrite input=/input/kx-amtrak-stations-SHP/amtrak-stations.shp output=$MAP snap=0.0001) 2>&1 | tee /output/logfile

The first grass command creates the environment necessary to run other GRASS commands, which is necessary to establish a region, projection, etc. In this case it's created on the basis of the input that is imported in the second grass command, which is run using --exec so that it is a standalone shell command that does not need to be run in an interactive GRASS session.

Lastly it's wrapped in brackets and stdout/stderr are piped to tee to be written in a log file. This should allow you to both see any output on the terminal, but also have it written to a file; it may be that Docker is swallowing your stderr which is why you can't see any error output.

GRASS's idioms are tricky, I recommend doing some introductory GRASS tutorials but noting that with a Docker container this idiom of using --exec is very useful.

Note especially that the output of v.in.ogr is not a path.