debug-generatefile

Overview

Generates a random binary file with the given size.

Running

Choose this gear from the Utility Gear menu, set the size of the output in the configuration and press the "Run Gear" button.

Inputs

None.

Config

size

Size of the output file in MB. The default is 1000.

Gear Testing and Development

To build, run build.sh

To test, run test.sh. This will drop you into a shell in the running container as if you are in the running gear. Run the gear with

cd /flywheel/v0/ ; ./run

Because gear/config.json is mounted in the container as config.json, you can edit it in another terminal window outside the container and then re-run the gear.

If you want to edit the run script outside the container and run it inside the container without stopping to re-build the container, just cd /src inside the container and then ./run.

How does this work? The current directory is mounted as /src and the gear/ directory is mounted inside the container to look like a running gear:

docker run -it --rm \
    --volume "$(pwd):/src" \
    --volume "$(pwd)/gear/config.json:/flywheel/v0/config.json" \
    --volume "$(pwd)/gear/input:/flywheel/v0/input" \
    --volume "$(pwd)/gear/output:/flywheel/v0/output" \
    --entrypoint=/bin/bash "${BASE}"

If you do run the gear inside /src, you probably should run ./cleanup.sh to remove the large useless output file.

Why would you want to do this? Because you can quickly test the gear as you create it. Since you are testing from inside the container, you can see exactly what is in the container (what packages are installed or missing) and can see the gear output. You can do this without having to upload the gear to see what happens and without waiting to re-build the gear after each change.

One major difference between this simulated gear and a real gear is the environment. The real gear executed on a Flywheel platform is run using runc and not docker run so it does not have the environment variables set as they are in the simulated gear. To fix this, type env inside the container and add any necessary environment variables to the manifest "environment" attribute. Also, be sure to set the PATH correctly so the desired executable can be found inside the container.

To upload your gear, log in to your flywheel site using the CLI, and then run ./upload.sh