Chainguard Container for wait-for-it

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

Chainguard Containers are regularly-updated, secure-by-default container images.

Download this Container Image

For those with access, this container image is available on cgr.dev:

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

Be sure to replace the ORGANIZATION placeholder with the name used for your organization's private repository within the Chainguard Registry.

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

What are Chainguard Containers?

Chainguard Containers are minimal container images that are secure by default.

In many cases, the Chainguard Containers tagged as :latest contain only an open-source application and its runtime dependencies. These minimal container images typically do not contain a shell or package manager. Chainguard Containers are built with Wolfi, our Linux undistro designed to produce container images that meet the requirements of a more secure software supply chain.

The main features of Chainguard Containers include:

• Minimal design, without unnecessary software bloat
• Daily builds to ensure container images are up-to-date with available security patches
• High quality build-time SBOMs attesting to the provenance of all artifacts within the image
• Verifiable signatures provided by Sigstore
• Reproducible builds with Cosign and apko (read more about reproducibility)

For cases where you need container images with shells and package managers to build or debug, most Chainguard Containers come paired with a -dev variant.

Although the -dev container image variants have similar security features as their more minimal versions, they feature additional software that is typically not necessary in production environments. We recommend using multi-stage builds to leverage the -dev variants, copying application artifacts into a final minimal container that offers a reduced attack surface that won’t allow package installations or logins.

Learn More

To better understand how to work with Chainguard Containers, please visit Chainguard Academy and Chainguard Courses.

In addition to Containers, Chainguard offers VMs and Libraries. Contact Chainguard to access additional products.

Trademarks

This software listing is packaged by Chainguard. The trademarks set forth in this offering are owned by their respective companies, and use of them does not imply any affiliation, sponsorship, or endorsement by such companies.