Tiny (< 9MB) CLI utility to perform health checks everywhere (container, local, etc)
# via docker
$ docker run --rm gregthebunny/go-healthcheck probe '{{ .Assert.HTTPStatusCode .HTTP.Handler "GET" "https://github.com" nil 200 }}'
# ... or from source
$ make build
# check if github.com is up
$ build/bin/healthcheck probe '{{ .Assert.HTTPStatusCode .HTTP.Handler "GET" "https://github.com" nil 200 }}'
INFO [16:47:40] starting probe probe=p0 status=STARTED
INFO [16:47:40] finished probe probe=p0 status=PASS
INFO [16:47:40] 1 of 1 probes passed 👍
EXIT 0NAME:
healthcheck - HealthCheck Utility
USAGE:
healthcheck [global options] command [command options] [arguments...]
COMMANDS:
probe Performs a HTTP connection check
help, h Shows a list of commands or help for one command
GLOBAL OPTIONS:
--help, -h show help (default: false)
--log-level value Set the log output verbosity (default: "info") [$HC_DEBUG]
--no-fail If set failed checks won't cause the program to exit with an error code (default: false) [$HC_NO_FAIL]
--no-fail-affirmative If set the program won't exit with an error code as long as at least one probe passed (default: false) [$HC_NO_FAIL_AFFIRMATIVE]
--output If set rendered output will be printed to stdout (default: false) [$HC_OUTPUT]
--timeout value Maximum time in seconds after an unfinished probe will fail (default: 30) [$HC_TIMEOUT]
# docker build -t hc-echo-example .
# docker run --name hc-echo-example --rm -p 5678:5678 hc-echo-example -text='my name is earl!'
# open http://localhost:5678
FROM hashicorp/http-echo
COPY --from=gregthebunny/go-healthcheck /bin/healthcheck /bin/healthcheck
ENV PROBE='{{ .Assert.HTTPBodyContains .HTTP.Handler "GET" "http://127.0.0.1:5678" nil "my name is earl!" }}'
HEALTHCHECK --start-period=10s --retries=3 --timeout=10s --interval=10s \
CMD ["/bin/healthcheck", "probe", "$PROBE"]
Now build and run:
$ docker build -t hc-echo-example .
$ docker run --name hc-echo-example --rm -p 5678:5678 hc-echo-example -text='my name is earl!'docker inspect --format "{{json .State.Health }}" hc-echo-example | jq
{
"Status": "healthy",
"FailingStreak": 0,
"Log": [
{
"Start": "2022-06-30T16:45:01.876566358Z",
"End": "2022-06-30T16:45:01.963092081Z",
"ExitCode": 0,
"Output": "time=\"16:45:01\" level=info msg=\"starting probe\" probe=p0 status=STARTED\ntime=\"16:45:01\" level=info msg=\"finished probe\" probe=p0 status=PASS\ntime=\"16:45:01\" level=info msg=\"1 of 1 probes passed 👍\"\n"
},
{
"Start": "2022-06-30T16:45:11.970180983Z",
"End": "2022-06-30T16:45:12.036572081Z",
"ExitCode": 0,
"Output": "time=\"16:45:12\" level=info msg=\"starting probe\" probe=p0 status=STARTED\ntime=\"16:45:12\" level=info msg=\"finished probe\" probe=p0 status=PASS\ntime=\"16:45:12\" level=info msg=\"1 of 1 probes passed 👍\"\n"
}
]
}$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f73899dc2b6c hc-echo-example "/http-echo '-text=m…" 2 minutes ago Up 2 minutes (healthy) 0.0.0.0:5678->5678/tcp hc-echo-example# play with env vars
$ MY_NAME=Earl ./healthcheck probe '{{ .Assert.Equal "My name is Earl!" ("My name is $MY_NAME!"|expandenv) }}'
INFO [16:19:52] starting probe probe=p0 status=STARTED
INFO [16:19:52] finished probe probe=p0 status=PASS
INFO [16:19:52] 1 of 1 probes passed 👍
EXIT 0
# run multiple probes
$ MY_NAME=Earl ./healthcheck probe '{{ .Assert.Equal "Me llamo Earl!" ("My name is $MY_NAME!"|expandenv) }}' \
'{{ .Assert.Equal "My name is Earl!" ("My name is $MY_NAME!"|expandenv) }}'
INFO [16:41:53] starting probe probe=p0 status=STARTED
WARNING[16:41:53]
Error: Not equal:
expected: "Me llamo Earl!"
actual : "My name is Earl!"
Diff:
--- Expected
+++ Actual
@@ -1 +1 @@
-Me llamo Earl!
+My name is Earl! probe=p0
WARNING[16:41:53] finished probe probe=p0 status=FAIL
INFO [16:41:53] starting probe probe=p1 status=STARTED
INFO [16:41:53] finished probe probe=p1 status=PASS
ERROR [16:41:53] 1 of 2 probes failed 😭
FAIL
EXIT 1Probes are basically go-templates (see "https://pkg.go.dev/text/template" to learn how utilize them) where you can perform assertions on static or dynamic values
The renderer comes with the Sprig extension to add some more convenience. See "http://masterminds.github.io/sprig/" for documentation and the sources on Github (https://github.com/Masterminds/sprig)
Here are some examples on how sprig can help you:
export HTTP_PORT=8080 healthcheck probe '{{ .Assert.Equal "http://localhost:8080" ("http://localhost:$HTTP_PORT"|expandenv) }}'
export HTTP_URL=http://localhost:8080 healthcheck probe '{{ .Assert.Equal "http://localhost:8080" ("HTTP_URL"|env) }}'Most assertions available in the probes are provided by Testify (see https://github.com/stretchr/testify). Have a look at the API Doc to see detailed information about it: https://pkg.go.dev/github.com/stretchr/testify@v1.8.0/assert#Assertions
Here are some examples on how you can use assertions in probes:
{{ .Assert.True false }}
{{ .Assert.Equal 200 (.HTTP.Request "GET" "http://localhost:8080").StatusCode }}
{{ .Assert.Regexp "^start"|regexp "its not starting" }}
{{ .Assert.NotRegexp (call .Regexp "^start") "its not starting" }}
{{ .Assert.HTTPStatusCode .HTTP.Handler "GET" "http://google.com" nil }}
{{ .Assert.HTTPError .HTTP.Handler "GET" "http://localhost:8080" nil }}
{{ .Assert.HTTPSuccess .HTTP.Handler "GET" "http://localhost:8080" nil }}
{{ .Assert.HTTPBodyContains .HTTP.Handler "GET" "http://localhost:8080" nil "hello world" }}
{{ .Assert.HTTPBodyNotContains .HTTP.Handler "GET" "http://localhost:8080" nil "hello world" }}
This tool is base on multiple awesome open source libraries shout-outs to:
- https://github.com/stretchr/testify
- https://github.com/Masterminds/sprig
- https://github.com/urfave/cli
MIT License
Copyright (c) 2022 Maximilian Reichel
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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