distribution/health/checks/checks.go
Sebastiaan van Stijn 1d33874951
go.mod: change imports to github.com/distribution/distribution/v3
Go 1.13 and up enforce import paths to be versioned if a project
contains a go.mod and has released v2 or up.

The current v2.x branches (and releases) do not yet have a go.mod,
and therefore are still allowed to be imported with a non-versioned
import path (go modules add a `+incompatible` annotation in that case).

However, now that this project has a `go.mod` file, incompatible
import paths will not be accepted by go modules, and attempting
to use code from this repository will fail.

This patch uses `v3` for the import-paths (not `v2`), because changing
import paths itself is a breaking change, which means that  the
next release should increment the "major" version to comply with
SemVer (as go modules dictate).

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2021-02-08 18:30:46 +01:00

74 lines
1.8 KiB
Go

package checks
import (
"errors"
"fmt"
"net"
"net/http"
"os"
"path/filepath"
"strconv"
"time"
"github.com/distribution/distribution/v3/health"
)
// FileChecker checks the existence of a file and returns an error
// if the file exists.
func FileChecker(f string) health.Checker {
return health.CheckFunc(func() error {
absoluteFilePath, err := filepath.Abs(f)
if err != nil {
return fmt.Errorf("failed to get absolute path for %q: %v", f, err)
}
_, err = os.Stat(absoluteFilePath)
if err == nil {
return errors.New("file exists")
} else if os.IsNotExist(err) {
return nil
}
return err
})
}
// HTTPChecker does a HEAD request and verifies that the HTTP status code
// returned matches statusCode.
func HTTPChecker(r string, statusCode int, timeout time.Duration, headers http.Header) health.Checker {
return health.CheckFunc(func() error {
client := http.Client{
Timeout: timeout,
}
req, err := http.NewRequest("HEAD", r, nil)
if err != nil {
return errors.New("error creating request: " + r)
}
for headerName, headerValues := range headers {
for _, headerValue := range headerValues {
req.Header.Add(headerName, headerValue)
}
}
response, err := client.Do(req)
if err != nil {
return errors.New("error while checking: " + r)
}
if response.StatusCode != statusCode {
return errors.New("downstream service returned unexpected status: " + strconv.Itoa(response.StatusCode))
}
return nil
})
}
// TCPChecker attempts to open a TCP connection.
func TCPChecker(addr string, timeout time.Duration) health.Checker {
return health.CheckFunc(func() error {
conn, err := net.DialTimeout("tcp", addr, timeout)
if err != nil {
return errors.New("connection to " + addr + " failed")
}
conn.Close()
return nil
})
}