open-nomad/vendor/github.com/gophercloud/gophercloud/util.go
Seth Hoenig 435c0d9fc8 deps: Switch to Go modules for dependency management
This PR switches the Nomad repository from using govendor to Go modules
for managing dependencies. Aspects of the Nomad workflow remain pretty
much the same. The usual Makefile targets should continue to work as
they always did. The API submodule simply defers to the parent Nomad
version on the repository, keeping the semantics of API versioning that
currently exists.
2020-06-02 14:30:36 -05:00

103 lines
2.7 KiB
Go

package gophercloud
import (
"fmt"
"net/url"
"path/filepath"
"strings"
"time"
)
// WaitFor polls a predicate function, once per second, up to a timeout limit.
// This is useful to wait for a resource to transition to a certain state.
// To handle situations when the predicate might hang indefinitely, the
// predicate will be prematurely cancelled after the timeout.
// Resource packages will wrap this in a more convenient function that's
// specific to a certain resource, but it can also be useful on its own.
func WaitFor(timeout int, predicate func() (bool, error)) error {
type WaitForResult struct {
Success bool
Error error
}
start := time.Now().Unix()
for {
// If a timeout is set, and that's been exceeded, shut it down.
if timeout >= 0 && time.Now().Unix()-start >= int64(timeout) {
return fmt.Errorf("A timeout occurred")
}
time.Sleep(1 * time.Second)
var result WaitForResult
ch := make(chan bool, 1)
go func() {
defer close(ch)
satisfied, err := predicate()
result.Success = satisfied
result.Error = err
}()
select {
case <-ch:
if result.Error != nil {
return result.Error
}
if result.Success {
return nil
}
// If the predicate has not finished by the timeout, cancel it.
case <-time.After(time.Duration(timeout) * time.Second):
return fmt.Errorf("A timeout occurred")
}
}
}
// NormalizeURL is an internal function to be used by provider clients.
//
// It ensures that each endpoint URL has a closing `/`, as expected by
// ServiceClient's methods.
func NormalizeURL(url string) string {
if !strings.HasSuffix(url, "/") {
return url + "/"
}
return url
}
// NormalizePathURL is used to convert rawPath to a fqdn, using basePath as
// a reference in the filesystem, if necessary. basePath is assumed to contain
// either '.' when first used, or the file:// type fqdn of the parent resource.
// e.g. myFavScript.yaml => file://opt/lib/myFavScript.yaml
func NormalizePathURL(basePath, rawPath string) (string, error) {
u, err := url.Parse(rawPath)
if err != nil {
return "", err
}
// if a scheme is defined, it must be a fqdn already
if u.Scheme != "" {
return u.String(), nil
}
// if basePath is a url, then child resources are assumed to be relative to it
bu, err := url.Parse(basePath)
if err != nil {
return "", err
}
var basePathSys, absPathSys string
if bu.Scheme != "" {
basePathSys = filepath.FromSlash(bu.Path)
absPathSys = filepath.Join(basePathSys, rawPath)
bu.Path = filepath.ToSlash(absPathSys)
return bu.String(), nil
}
absPathSys = filepath.Join(basePath, rawPath)
u.Path = filepath.ToSlash(absPathSys)
if err != nil {
return "", err
}
u.Scheme = "file"
return u.String(), nil
}