Zero Bundle

runs a mini env flist on linux.

Operation

zbundle, uses 0-fs to mount an flist then automatically chroot, and run the start point of the env

• once the flist is mounted, zbundle reads the /etc/env file
• next, zbundle runs /etc/start inside the chroot with the env variables loaded from /etc/env
• zbundle shows all the output of the start process on stdout, and stderr and exits once the start process exits

env file format

since NOT all flists will have a shell (bash, sh, or others) it will not be possible to initialize the env vars of the start process. A special (optional) env file is used to setup the env vars of the start process.

Note: all env vars from the env file can be overridedn from the zbundle command line with the -e flag

example env file

# set up the path
PATH=/bin:/usr/bin

# set up the version
VERSION=1.0

start file

After loading the env from the /etc/env file, next zbundle will execute the /etc/start script. All the env variables from the env file, plus the ones defined from the command line are gonna be available to the start excutable.

• /etc/start MUST have excute permission (chmod a+x /etc/start)
• if start is a shell script, the excuting shebang must actually be part of the flist otherwise it will not work, because the flist runs in a chroot, there is noway to access the binaries from the host.

Note: you can always override the entry point by using --entry-point flag

Note: all command line arguments provided after the flist, are passed to the entry point as arguments

Notes

• the env file is NOT a shell script
• empty lines and lines starting with # are ignored

Example

zbundle --id test https://hub.gig.tech/azmy/bundle-test.flist

Error reporting upstream

If the sandboxed exited with an error, the last 32KB of both stdout, and stderr and collected along with the exit error, and then reported to ALL provided report flag

report is a url to the required report endpoint. We only currently support redis and redis+tls

• for redis, the url formated like redis://host:port
• for redis+tls, the url is formated like redis+tls://host:port

Help

~ zbundle --help
NAME:
   zbundle - run mini environments from flist

USAGE:
   zbundle [options] <flist> <args>

VERSION:
   1.0

COMMANDS:
     help, h  Shows a list of commands or help for one command

GLOBAL OPTIONS:
   --id value, -i value       [required] ID of the sandbox
   --entry-point value        sandbox entry point (default: "/etc/start")
   --env value, -e value      custom environemt variables
   --report value, -r value   report error back on failures to the given url
   --storage value, -s value  storage url to use (default: "ardb://hub.gig.tech:16379")
   --debug, -d                run in debug mode
   --no-exit                  do not terminate (unmount the sandbox) after /etc/start exits
   --help, -h                 show help
   --version, -v              print the version

Owner

muhamadazmy