# Pinglish
A simple Rack middleware for checking application health. Pinglish
exposes a `/_ping` resource via HTTP `GET`, returning JSON that
conforms to the spec below.
## The Spec
0. The application __must__ respond to `GET /_ping` as an HTTP request.
0. The request handler __should__ check the health of all services the
application depends on, answering questions like, "Can I query
against my MySQL database," "Can I create/read keys in Redis," or "How
many docs are in my ElasticSearch index?"
0. The response __must__ return within 29 seconds. This is one second
less than the default timeout for many monitoring services.
0. The response __must__ return an `HTTP 200 OK` status code if all
health checks pass.
0. The response __must__ return an `HTTP 503 SERVICE UNAVAILABLE`
status code if any health checks fail.
0. The response __must__ be of Content-Type `application/json;
charset=UTF-8`.
0. The response __must__ be valid JSON no matter what, even if JSON
serialization or other fundamental code fails.
0. The response __must__ contain a `"status"` key set either to `"ok"`
or `"failures"`.
0. The response __must__ contain a `"now"` key set to the current
server's time in seconds since epoch as a string.
0. If the `"status"` key is set to `"failures"`, the response __may__
contain a `"failures"` key set to an Array of string names
representing failed checks.
0. If the `"status"` key is set to `"failures"`, the response __may__
contain a `"timeouts"` key set to an Array of string names
representing checks that exceeded an implementation-specific
individual timeout.
0. The response body __may__ contain any other top-level keys to
supply additional data about services the application consumes, but
all values must be strings, arrays of strings, or hashes where both
keys and values are strings.
### An Example Response
```javascript
{
// These two keys will always exist.
"now": "1359055102",
"status": "failures",
// This key may only exist when a named check has failed.
"failures": ["db"],
// This key may only exist when a named check exceeds its timeout.
"timeouts": ["really-long-check"],
// Keys like this may exist to provide extra information about
// healthy services, like the number of objects in an S3 bucket.
"s3": "127"
}
```
## The Middleware
```ruby
require "pinglish"
use Pinglish do |ping|
# A single unnamed check is the simplest possible way to use
# Pinglish, and you'll probably never want combine it with other
# named checks. An unnamed check contributes to overall success or
# failure, but never adds additional data to the response.
ping.check do
App.healthy?
end
# A named check like this can provide useful summary information
# when it succeeds. In this case, a top-level "db" key will appear
# in the response containing the number of items in the database. If
# a check returns nil, no key will be added to the response.
ping.check :db do
App.db.items.size
end
# By default, checks time out after one second. You can override
# this with the :timeout option, but be aware that no combination of
# checks is ever allowed to exceed the overall 29 second limit.
ping.check :long, :timeout => 5 do
App.dawdle
end
# Signal check failure by raising an exception. Any exception will do.
ping.check :fails do
raise "Everything's ruined."
end
# Additionally, any check that returns false is counted as a failure.
ping.check :false_fails do
false
end
end
```
用于检查应用程序健康状况的简单Rack中间件 -Ruby-Shell-下载
需积分: 1 199 浏览量
2023-01-09
13:57:52
上传
评论
收藏 9KB ZIP 举报
用于检查应用程序健康状况的简单Rack中间件。.zip （13个子文件） 
pinglish-master lib 
pinglish.rb 4KB pinglish check.rb 448B LICENSE 1KB Gemfile 38B pinglish.gemspec 700B test pinglish_test.rb 6KB helper.rb 46B check_test.rb 546B .gitignore 30B script bootstrap 193B release 723B test 193B README.md 3KB资源评论
