66 lines
2.1 KiB
Go
66 lines
2.1 KiB
Go
package client // import "github.com/docker/docker/client"
|
|
|
|
import (
|
|
"context"
|
|
"net/http"
|
|
"path"
|
|
|
|
"github.com/docker/docker/api/types"
|
|
"github.com/docker/docker/errdefs"
|
|
)
|
|
|
|
// Ping pings the server and returns the value of the "Docker-Experimental",
|
|
// "Builder-Version", "OS-Type" & "API-Version" headers. It attempts to use
|
|
// a HEAD request on the endpoint, but falls back to GET if HEAD is not supported
|
|
// by the daemon.
|
|
func (cli *Client) Ping(ctx context.Context) (types.Ping, error) {
|
|
var ping types.Ping
|
|
|
|
// Using cli.buildRequest() + cli.doRequest() instead of cli.sendRequest()
|
|
// because ping requests are used during API version negotiation, so we want
|
|
// to hit the non-versioned /_ping endpoint, not /v1.xx/_ping
|
|
req, err := cli.buildRequest(http.MethodHead, path.Join(cli.basePath, "/_ping"), nil, nil)
|
|
if err != nil {
|
|
return ping, err
|
|
}
|
|
serverResp, err := cli.doRequest(ctx, req)
|
|
if err == nil {
|
|
defer ensureReaderClosed(serverResp)
|
|
switch serverResp.statusCode {
|
|
case http.StatusOK, http.StatusInternalServerError:
|
|
// Server handled the request, so parse the response
|
|
return parsePingResponse(cli, serverResp)
|
|
}
|
|
} else if IsErrConnectionFailed(err) {
|
|
return ping, err
|
|
}
|
|
|
|
req, err = cli.buildRequest(http.MethodGet, path.Join(cli.basePath, "/_ping"), nil, nil)
|
|
if err != nil {
|
|
return ping, err
|
|
}
|
|
serverResp, err = cli.doRequest(ctx, req)
|
|
defer ensureReaderClosed(serverResp)
|
|
if err != nil {
|
|
return ping, err
|
|
}
|
|
return parsePingResponse(cli, serverResp)
|
|
}
|
|
|
|
func parsePingResponse(cli *Client, resp serverResponse) (types.Ping, error) {
|
|
var ping types.Ping
|
|
if resp.header == nil {
|
|
err := cli.checkResponseErr(resp)
|
|
return ping, errdefs.FromStatusCode(err, resp.statusCode)
|
|
}
|
|
ping.APIVersion = resp.header.Get("API-Version")
|
|
ping.OSType = resp.header.Get("OSType")
|
|
if resp.header.Get("Docker-Experimental") == "true" {
|
|
ping.Experimental = true
|
|
}
|
|
if bv := resp.header.Get("Builder-Version"); bv != "" {
|
|
ping.BuilderVersion = types.BuilderVersion(bv)
|
|
}
|
|
err := cli.checkResponseErr(resp)
|
|
return ping, errdefs.FromStatusCode(err, resp.statusCode)
|
|
}
|