Documentation
¶
Overview ¶
Package selector
`selector` a generic server-side selector middleware for gRPC.
# Server Side Selector Middleware It allows to set check rules to allowlist or blocklist middleware such as Auth interceptors to toggle behavior on or off based on the request path.
Please see examples for simple examples of use.
Example (Login) ¶
package main
import (
"context"
"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors"
"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors/auth"
"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors/logging"
"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors/selector"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/status"
)
var tokenInfoKey struct{}
func parseToken(token string) (struct{}, error) {
return struct{}{}, nil
}
func userClaimFromToken(struct{}) string {
return "foobar"
}
// exampleAuthFunc is used by a middleware to authenticate requests
func exampleAuthFunc(ctx context.Context) (context.Context, error) {
token, err := auth.AuthFromMD(ctx, "bearer")
if err != nil {
return nil, err
}
tokenInfo, err := parseToken(token)
if err != nil {
return nil, status.Errorf(codes.Unauthenticated, "invalid auth token: %v", err)
}
ctx = logging.InjectFields(ctx, logging.Fields{"auth.sub", userClaimFromToken(tokenInfo)})
return context.WithValue(ctx, tokenInfoKey, tokenInfo), nil
}
func loginSkip(_ context.Context, c interceptors.CallMeta) bool {
return c.FullMethod() != "/auth.v1.AuthService/Login"
}
func main() {
_ = grpc.NewServer(
grpc.ChainUnaryInterceptor(
selector.UnaryServerInterceptor(auth.UnaryServerInterceptor(exampleAuthFunc), selector.MatchFunc(loginSkip)),
),
grpc.ChainStreamInterceptor(
selector.StreamServerInterceptor(auth.StreamServerInterceptor(exampleAuthFunc), selector.MatchFunc(loginSkip)),
),
)
}
Output:
Example (Ratelimit) ¶
package main
import (
"context"
"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors"
"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors/ratelimit"
"github.com/grpc-ecosystem/go-grpc-middleware/v2/interceptors/selector"
"google.golang.org/grpc"
)
// alwaysPassLimiter is an example limiter which implements Limiter interface.
// It does not limit any request because Limit function always returns false.
type alwaysPassLimiter struct{}
func (*alwaysPassLimiter) Limit(_ context.Context) error {
return nil
}
func healthSkip(_ context.Context, c interceptors.CallMeta) bool {
return c.FullMethod() != "/ping.v1.PingService/Health"
}
func main() {
limiter := &alwaysPassLimiter{}
_ = grpc.NewServer(
grpc.ChainUnaryInterceptor(
selector.UnaryServerInterceptor(ratelimit.UnaryServerInterceptor(limiter), selector.MatchFunc(healthSkip)),
),
grpc.ChainStreamInterceptor(
selector.StreamServerInterceptor(ratelimit.StreamServerInterceptor(limiter), selector.MatchFunc(healthSkip)),
),
)
}
Output:
Index ¶
- func StreamClientInterceptor(i grpc.StreamClientInterceptor, matcher Matcher) grpc.StreamClientInterceptor
- func StreamServerInterceptor(i grpc.StreamServerInterceptor, matcher Matcher) grpc.StreamServerInterceptor
- func UnaryClientInterceptor(i grpc.UnaryClientInterceptor, matcher Matcher) grpc.UnaryClientInterceptor
- func UnaryServerInterceptor(i grpc.UnaryServerInterceptor, matcher Matcher) grpc.UnaryServerInterceptor
- type Matcher
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func StreamClientInterceptor ¶
func StreamClientInterceptor(i grpc.StreamClientInterceptor, matcher Matcher) grpc.StreamClientInterceptor
StreamClientInterceptor returns a new stream client interceptor that will decide whether to call the interceptor based on the return argument from the Matcher. TODO(bwplotka): Write unit test.
func StreamServerInterceptor ¶
func StreamServerInterceptor(i grpc.StreamServerInterceptor, matcher Matcher) grpc.StreamServerInterceptor
StreamServerInterceptor returns a new stream server interceptor that will decide whether to call the interceptor based on the return argument from the Matcher.
func UnaryClientInterceptor ¶
func UnaryClientInterceptor(i grpc.UnaryClientInterceptor, matcher Matcher) grpc.UnaryClientInterceptor
UnaryClientInterceptor returns a new unary client interceptor that will decide whether to call the interceptor based on the return argument from the Matcher. TODO(bwplotka): Write unit test.
func UnaryServerInterceptor ¶
func UnaryServerInterceptor(i grpc.UnaryServerInterceptor, matcher Matcher) grpc.UnaryServerInterceptor
UnaryServerInterceptor returns a new unary server interceptor that will decide whether to call the interceptor based on the return argument from the Matcher.
Source Files