Image Overview: wait-for-it

Overview: wait-for-it Chainguard Image

Container image for testing whether a service is listening on an address/port combination.

Get It!

The image is available on cgr.dev:

docker pull cgr.dev/chainguard/wait-for-it:latest

Usage

Simple Example

Test that a service is available!

$ docker run cgr.dev/chainguard/wait-for-it:latest -h google.com -p 80
wait-for-it: waiting 15 seconds for google.com:80
wait-for-it: google.com:80 is available after 0 seconds

Timeout

You can optionally specify a timeout using the -t flag (in seconds):

$  docker run cgr.dev/chainguard/wait-for-it:latest -h fake.doesnotexist -p 80 -t 5
wait-for-it: waiting 5 seconds for fake.doesnotexist:80
wait-for-it: timeout occurred after waiting 5 seconds for fake.doesnotexist:80

Subcommand

You can then run a command after the execution, using the -- syntax.

$ docker run cgr.dev/chainguard/wait-for-it:latest -h fake.doesnotexist -p 80 -t 5 -- echo hello
wait-for-it: waiting 5 seconds for fake.doesnotexist:80
wait-for-it: timeout occurred after waiting 5 seconds for fake.doesnotexist:80
hello

Adding -s will only run the command if wait-for-it succeeds:

$ docker run cgr.dev/chainguard/wait-for-it:latest -h fake.doesnotexist -p 80 -t 5 -s -- echo hello
wait-for-it: waiting 5 seconds for fake.doesnotexist:80
wait-for-it: timeout occurred after waiting 5 seconds for fake.doesnotexist:80
wait-for-it: strict mode, refusing to execute subprocess