mjpitz/service-precheck
Init container used to quickly check your service dependencies
Image
0
8.5K
mjpitz/service-precheck repository overview
service-precheck
Simple init container that ensures upstream services are ready before starting the primary container of a pod. This implementation is largely based on Alibaba's blog post on how to solve service dependencies in Kubernetes.
In order to use this container to precheck services, your upstream systems should have liveness and readiness probes configured.
Status
Getting Started
Try out the container using a quick docker run command:
$ docker run -it --rm mjpitz/service-precheck google.com amazon.com
[google.com] checking for a dns entry
Server: 192.168.65.1
Address: 192.168.65.1#53
Non-authoritative answer:
Name: google.com
Address: 172.217.9.142
[amazon.com] checking for a dns entry
Server: 192.168.65.1
Address: 192.168.65.1#53
Non-authoritative answer:
Name: amazon.com
Address: 176.32.103.205
Name: amazon.com
Address: 176.32.98.166
Name: amazon.com
Address: 205.251.242.103
Or try it within a Kubernetes cluster:
$ kubectl run -it --restart=Never --image mjpitz/service-precheck precheck -- kubernetes google.com amazon.com
$ kubectl logs -f precheck
[kubernetes] checking for a dns entry
Server: 10.43.0.10
Address: 10.43.0.10#53
Name: kubernetes.default.svc.cluster.local
Address: 10.43.0.1
[google.com] checking for a dns entry
Server: 10.43.0.10
Address: 10.43.0.10#53
Non-authoritative answer:
Name: google.com
Address: 216.58.194.78
[amazon.com] checking for a dns entry
Server: 10.43.0.10
Address: 10.43.0.10#53
Non-authoritative answer:
Name: amazon.com
Address: 205.251.242.103
Name: amazon.com
Address: 176.32.103.205
Name: amazon.com
Address: 176.32.98.166
$ kubectl delete pod precheck
Once you've tried it out, you can add it to your deployment configuration:
spec:
initContainers:
- name: service-precheck
image: mjpitz/service-precheck:latest
imagePullPolicy: IfNotPresent
args:
- "kubernetes"
- "google.com"
- "amazon.com"
Tag summary
Content type
Image
Digest
Size
54.6 MB
Last updated
about 7 years ago
docker pull mjpitz/service-precheck