Files
sendico/api/pkg/discovery/client.go
2026-01-06 17:51:35 +01:00

140 lines
3.1 KiB
Go

package discovery
import (
"context"
"encoding/json"
"strings"
"sync"
"github.com/google/uuid"
msg "github.com/tech/sendico/pkg/messaging"
mb "github.com/tech/sendico/pkg/messaging/broker"
cons "github.com/tech/sendico/pkg/messaging/consumer"
me "github.com/tech/sendico/pkg/messaging/envelope"
msgproducer "github.com/tech/sendico/pkg/messaging/producer"
"github.com/tech/sendico/pkg/merrors"
"github.com/tech/sendico/pkg/mlogger"
"go.uber.org/zap"
)
type Client struct {
logger mlogger.Logger
producer msg.Producer
consumer msg.Consumer
sender string
mu sync.Mutex
pending map[string]chan LookupResponse
}
func NewClient(logger mlogger.Logger, msgBroker mb.Broker, producer msg.Producer, sender string) (*Client, error) {
if msgBroker == nil {
return nil, merrors.InvalidArgument("discovery client: broker is nil")
}
if logger == nil {
logger = zap.NewNop()
}
logger = logger.Named("discovery_client")
if producer == nil {
producer = msgproducer.NewProducer(logger, msgBroker)
}
sender = strings.TrimSpace(sender)
if sender == "" {
sender = "discovery_client"
}
consumer, err := cons.NewConsumer(logger, msgBroker, LookupResponseEvent())
if err != nil {
return nil, err
}
client := &Client{
logger: logger,
producer: producer,
consumer: consumer,
sender: sender,
pending: map[string]chan LookupResponse{},
}
go func() {
if err := consumer.ConsumeMessages(client.handleLookupResponse); err != nil {
client.logger.Warn("Discovery lookup consumer stopped", zap.String("event", LookupResponseEvent().ToString()), zap.Error(err))
}
}()
return client, nil
}
func (c *Client) Close() {
if c == nil {
return
}
if c.consumer != nil {
c.consumer.Close()
}
c.mu.Lock()
for key, ch := range c.pending {
close(ch)
delete(c.pending, key)
}
c.mu.Unlock()
}
func (c *Client) Lookup(ctx context.Context) (LookupResponse, error) {
if c == nil || c.producer == nil {
return LookupResponse{}, merrors.Internal("discovery client: producer not configured")
}
requestID := uuid.NewString()
ch := make(chan LookupResponse, 1)
c.mu.Lock()
c.pending[requestID] = ch
c.mu.Unlock()
defer func() {
c.mu.Lock()
delete(c.pending, requestID)
c.mu.Unlock()
}()
req := LookupRequest{RequestID: requestID}
if err := c.producer.SendMessage(NewLookupRequestEnvelope(c.sender, req)); err != nil {
return LookupResponse{}, err
}
select {
case <-ctx.Done():
return LookupResponse{}, ctx.Err()
case resp := <-ch:
return resp, nil
}
}
func (c *Client) handleLookupResponse(_ context.Context, env me.Envelope) error {
var payload LookupResponse
if err := json.Unmarshal(env.GetData(), &payload); err != nil {
fields := append(envelopeFields(env), zap.Int("data_len", len(env.GetData())), zap.Error(err))
c.logWarn("Failed to decode discovery lookup response", fields...)
return err
}
requestID := strings.TrimSpace(payload.RequestID)
if requestID == "" {
return nil
}
c.mu.Lock()
ch := c.pending[requestID]
c.mu.Unlock()
if ch != nil {
ch <- payload
}
return nil
}
func (c *Client) logWarn(message string, fields ...zap.Field) {
if c == nil {
return
}
c.logger.Warn(message, fields...)
}