1
0
Fork 0
mirror of https://github.com/moby/moby.git synced 2022-11-09 12:21:53 -05:00
moby--moby/daemon/logger/plugin.go
Peter Bücker e908e1a357 Logging driver should receive same file in start/stop request
Signed-off-by: Peter Bücker <peter.buecker@gmail.com>
2017-06-08 10:05:52 +02:00

90 lines
2.2 KiB
Go

package logger
import (
"fmt"
"io"
"os"
"path/filepath"
"strings"
"github.com/docker/docker/api/types/plugins/logdriver"
getter "github.com/docker/docker/pkg/plugingetter"
"github.com/docker/docker/pkg/stringid"
"github.com/pkg/errors"
)
var pluginGetter getter.PluginGetter
const extName = "LogDriver"
// logPlugin defines the available functions that logging plugins must implement.
type logPlugin interface {
StartLogging(streamPath string, info Info) (err error)
StopLogging(streamPath string) (err error)
Capabilities() (cap Capability, err error)
ReadLogs(info Info, config ReadConfig) (stream io.ReadCloser, err error)
}
// RegisterPluginGetter sets the plugingetter
func RegisterPluginGetter(plugingetter getter.PluginGetter) {
pluginGetter = plugingetter
}
// GetDriver returns a logging driver by its name.
// If the driver is empty, it looks for the local driver.
func getPlugin(name string, mode int) (Creator, error) {
p, err := pluginGetter.Get(name, extName, mode)
if err != nil {
return nil, fmt.Errorf("error looking up logging plugin %s: %v", name, err)
}
d := &logPluginProxy{p.Client()}
return makePluginCreator(name, d, p.BasePath()), nil
}
func makePluginCreator(name string, l *logPluginProxy, basePath string) Creator {
return func(logCtx Info) (logger Logger, err error) {
defer func() {
if err != nil {
pluginGetter.Get(name, extName, getter.Release)
}
}()
root := filepath.Join(basePath, "run", "docker", "logging")
if err := os.MkdirAll(root, 0700); err != nil {
return nil, err
}
id := stringid.GenerateNonCryptoID()
a := &pluginAdapter{
driverName: name,
id: id,
plugin: l,
basePath: basePath,
fifoPath: filepath.Join(root, id),
logInfo: logCtx,
}
cap, err := a.plugin.Capabilities()
if err == nil {
a.capabilities = cap
}
stream, err := openPluginStream(a)
if err != nil {
return nil, err
}
a.stream = stream
a.enc = logdriver.NewLogEntryEncoder(a.stream)
if err := l.StartLogging(strings.TrimPrefix(a.fifoPath, basePath), logCtx); err != nil {
return nil, errors.Wrapf(err, "error creating logger")
}
if cap.ReadLogs {
return &pluginAdapterWithRead{a}, nil
}
return a, nil
}
}