gatus

A service health dashboard in Go that is meant to be used as a docker image with a custom configuration file.

I personally deploy it in my Kubernetes cluster and have it monitor the status of my core applications: https://status.twinnation.org/

Usage

By default, the configuration file is expected to be at config/config.yaml.

You can specify a custom path by setting the GATUS_CONFIG_FILE environment variable.

Here's a simple example:

metrics: true         # Whether to expose metrics at /metrics
services:
  - name: twinnation  # Name of your service, can be anything
    url: https://twinnation.org/health
    interval: 15s     # Duration to wait between every status check (default: 10s)
    conditions:
      - "[STATUS] == 200"         # Status must be 200
      - "[BODY].status == UP"     # The json path "$.status" must be equal to UP
      - "[RESPONSE_TIME] < 300"   # Response time must be under 300ms
  - name: example
    url: https://example.org/
    interval: 30s
    conditions:
      - "[STATUS] == 200"

Note that you can also add environment variables in the your configuration file (i.e. $DOMAIN, ${DOMAIN})

Configuration

Parameter	Description	Default
metrics	Whether to expose metrics at /metrics	false
services[].name	Name of the service. Can be anything.	Required ""
services[].url	URL to send the request to	Required ""
services[].conditions	Conditions used to determine the health of the service	[]
services[].interval	Duration to wait between every status check	10s
services[].method	Request method	GET
services[].graphql	Whether to wrap the body in a query param ({"query":"$body"})	false
services[].body	Request body	""
services[].headers	Request headers	{}

Conditions

Here are some examples of conditions you can use:

Condition	Description	Passing values	Failing values
[STATUS] == 200	Status must be equal to 200	200	201, 404, 500
[STATUS] < 300	Status must lower than 300	200, 201, 299	301, 302, 400, 500
[STATUS] <= 299	Status must be less than or equal to 299	200, 201, 299	301, 302, 400, 500
[STATUS] > 400	Status must be greater than 400	401, 402, 403, 404	200, 201, 300, 400
[RESPONSE_TIME] < 500	Response time must be below 500ms	100ms, 200ms, 300ms	500ms, 1500ms
[BODY] == 1	The body must be equal to 1	1	literally anything else
[BODY].data.id == 1	The jsonpath $.data.id is equal to 1	{"data":{"id":1}}	literally anything else
[BODY].data[0].id == 1	The jsonpath $.data[0].id is equal to 1	{"data":[{"id":1}]}	literally anything else
len([BODY].data) > 0	Array at jsonpath $.data has less than 5 elements	{"data":[{"id":1}]}	{"data":[{"id":1}]}
len([BODY].name) == 8	String at jsonpath $.name has a length of 8	{"name":"john.doe"}	{"name":"bob"}

NOTE: [BODY] with JSON path (i.e. [BODY].id == 1) is currently in BETA. For the most part, the only thing that doesn't work is arrays.

Docker

Building the Docker image is done as following:

docker build . -t gatus

You can then run the container with the following command:

docker run -p 8080:8080 --name gatus gatus

Running the tests

go test ./... -mod vendor

Using in Production

See the example folder.

FAQ

Sending a GraphQL request

By setting services[].graphql to true, the body will automatically be wrapped by the standard GraphQL query parameter.

For instance, the following configuration:

services:
  - name: filter users by gender
    url: http://localhost:8080/playground
    method: POST
    graphql: true
    body: |
      {
        user(gender: "female") {
          id
          name
          gender
          avatar
        }
      }      
    headers:
      Content-Type: application/json
    conditions:
      - "[STATUS] == 200"
      - "[BODY].data.user[0].gender == female"

will send a POST request to http://localhost:8080/playground with the following body:

{"query":"      {\n        user(gender: \"female\") {\n          id\n          name\n          gender\n          avatar\n        }\n      }"}