open-consul/connect/proxy/proxy.go

135 lines
3.2 KiB
Go

package proxy
import (
"log"
"github.com/hashicorp/consul/api"
"github.com/hashicorp/consul/connect"
)
// Proxy implements the built-in connect proxy.
type Proxy struct {
proxyID string
client *api.Client
cfgWatcher ConfigWatcher
stopChan chan struct{}
logger *log.Logger
}
// NewFromConfigFile returns a Proxy instance configured just from a local file.
// This is intended mostly for development and bypasses the normal mechanisms
// for fetching config and certificates from the local agent.
func NewFromConfigFile(client *api.Client, filename string,
logger *log.Logger) (*Proxy, error) {
cfg, err := ParseConfigFile(filename)
if err != nil {
return nil, err
}
service, err := connect.NewDevServiceFromCertFiles(cfg.ProxiedServiceID,
client, logger, cfg.DevCAFile, cfg.DevServiceCertFile,
cfg.DevServiceKeyFile)
if err != nil {
return nil, err
}
cfg.service = service
p := &Proxy{
proxyID: cfg.ProxyID,
client: client,
cfgWatcher: NewStaticConfigWatcher(cfg),
stopChan: make(chan struct{}),
logger: logger,
}
return p, nil
}
// New returns a Proxy with the given id, consuming the provided (configured)
// agent. It is ready to Run().
func New(client *api.Client, proxyID string, logger *log.Logger) (*Proxy, error) {
p := &Proxy{
proxyID: proxyID,
client: client,
cfgWatcher: &AgentConfigWatcher{
client: client,
proxyID: proxyID,
logger: logger,
},
stopChan: make(chan struct{}),
logger: logger,
}
return p, nil
}
// Serve the proxy instance until a fatal error occurs or proxy is closed.
func (p *Proxy) Serve() error {
var cfg *Config
// Watch for config changes (initial setup happens on first "change")
for {
select {
case newCfg := <-p.cfgWatcher.Watch():
p.logger.Printf("[DEBUG] got new config")
if newCfg.service == nil {
p.logger.Printf("[ERR] new config has nil service")
continue
}
if cfg == nil {
// Initial setup
newCfg.PublicListener.applyDefaults()
l := NewPublicListener(newCfg.service, newCfg.PublicListener, p.logger)
err := p.startListener("public listener", l)
if err != nil {
return err
}
}
// TODO(banks) update/remove upstreams properly based on a diff with current. Can
// store a map of uc.String() to Listener here and then use it to only
// start one of each and stop/modify if changes occur.
for _, uc := range newCfg.Upstreams {
uc.applyDefaults()
uc.resolver = UpstreamResolverFromClient(p.client, uc)
l := NewUpstreamListener(newCfg.service, uc, p.logger)
err := p.startListener(uc.String(), l)
if err != nil {
p.logger.Printf("[ERR] failed to start upstream %s: %s", uc.String(),
err)
}
}
cfg = newCfg
case <-p.stopChan:
return nil
}
}
}
// startPublicListener is run from the internal state machine loop
func (p *Proxy) startListener(name string, l *Listener) error {
go func() {
err := l.Serve()
if err != nil {
p.logger.Printf("[ERR] %s stopped with error: %s", name, err)
return
}
p.logger.Printf("[INFO] %s stopped", name)
}()
go func() {
<-p.stopChan
l.Close()
}()
return nil
}
// Close stops the proxy and terminates all active connections. It must be
// called only once.
func (p *Proxy) Close() {
close(p.stopChan)
}