2020-12-31 22:13:22 -05:00
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# `wait.kontain.me`
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`docker pull wait.kontain.me/some-unique-string` enqueues a background task to
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generate a random image, which will eventually be served.
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By default, the task runs after 10 seconds. You can request the delay time (up
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to one hour) using the image tag.
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After an image is generated for the unique string, it will be served until the
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image is evicted in the next 24 hours.
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## Examples
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Pull a random image available in 10 seconds:
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```
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docker pull wait.kontain.me/blah-blah
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```
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Pull a random image available in 30 seconds:
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```
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docker pull wait.kontain.me/random:30s
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```
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2021-01-02 14:30:10 -05:00
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## Demo
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This screencast requests an image that should exist in five seconds, then waits
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to see it appear and checks that it's valid.
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[](https://asciinema.org/a/JUiiq33BaGF3NGx10PP6uvETf)
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2021-04-09 12:38:33 -04:00
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## Why?
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This demonstrates being able to asynchronously produce an image, rather than
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blocking the initial pull HTTP request until the image is available.
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A container orchestrator like Kubernetes would pull this image and report
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`ImagePullBackoff` until the image was finally served, at which point it would
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pull and run it. In the meantime, the registry could be building or mirroring
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or modifying the image in the background.
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