Files
argo-cd/util/grpc/useragent.go
2025-05-21 15:56:25 -04:00

94 lines
3.7 KiB
Go

package grpc
import (
"context"
"errors"
"strings"
"github.com/Masterminds/semver/v3"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/metadata"
"google.golang.org/grpc/status"
)
// parseSemVerConstraint returns a semVer Constraint instance or panic if there is a parsing error with the provided constraint.
func parseSemVerConstraint(constraintStr string) *semver.Constraints {
semVerConstraint, err := semver.NewConstraint(constraintStr)
if err != nil {
panic(err)
}
return semVerConstraint
}
// UserAgentUnaryServerInterceptor returns a UnaryServerInterceptor which enforces a minimum client
// version in the user agent
func UserAgentUnaryServerInterceptor(clientName, constraintStr string) grpc.UnaryServerInterceptor {
semVerConstraint := parseSemVerConstraint(constraintStr)
return func(ctx context.Context, req any, _ *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (any, error) {
if err := userAgentEnforcer(ctx, clientName, semVerConstraint); err != nil {
return nil, err
}
return handler(ctx, req)
}
}
// UserAgentStreamServerInterceptor returns a StreamServerInterceptor which enforces a minimum client
// version in the user agent
func UserAgentStreamServerInterceptor(clientName, constraintStr string) grpc.StreamServerInterceptor {
semVerConstraint := parseSemVerConstraint(constraintStr)
return func(srv any, stream grpc.ServerStream, _ *grpc.StreamServerInfo, handler grpc.StreamHandler) error {
if err := userAgentEnforcer(stream.Context(), clientName, semVerConstraint); err != nil {
return err
}
return handler(srv, stream)
}
}
func userAgentEnforcer(ctx context.Context, clientName string, semVerConstraint *semver.Constraints) error {
var userAgents []string
if md, ok := metadata.FromIncomingContext(ctx); ok {
for _, ua := range md["user-agent"] {
// ua is a string like "argocd-client/v0.11.0+cde040e grpc-go/1.15.0"
userAgents = append(userAgents, strings.Fields(ua)...)
break
}
}
if isLegacyClient(userAgents) {
return status.Errorf(codes.FailedPrecondition, "unsatisfied client version constraint: %s", semVerConstraint)
}
for _, userAgent := range userAgents {
uaSplit := strings.Split(userAgent, "/")
if len(uaSplit) != 2 || uaSplit[0] != clientName {
// User-agent was supplied, but client/format is not one we care about (e.g. grpc-go)
continue
}
// remove pre-release part
versionStr := strings.Split(uaSplit[1], "-")[0]
// We have matched the client name to the one we care about
uaVers, err := semver.NewVersion(versionStr)
if err != nil {
return status.Errorf(codes.InvalidArgument, "could not parse version from user-agent: %s", userAgent)
}
if ok, errs := semVerConstraint.Validate(uaVers); !ok {
return status.Errorf(codes.FailedPrecondition, "unsatisfied client version constraint: %s", errors.Join(errs...))
}
return nil
}
// If we get here, the caller either did not supply user-agent, supplied one which we don't
// care about. This implies it is a from a custom generated client, so we permit the request.
// We really only want to enforce user-agent version constraints for clients under our
// control which we know to have compatibility issues
return nil
}
// isLegacyClient checks if the request was made from a legacy Argo CD client (i.e. v0.10 CLI).
// The heuristic is that a single default 'grpc-go' user-agent was specified with one of the
// previous versions of grpc-go we used in the past (1.15.0, 1.10.0).
// Starting in v0.11, both of the gRPC clients we maintain (pkg/apiclient and grpc-gateway) started
// supplying a explicit user-agent tied to the Argo CD version.
func isLegacyClient(userAgents []string) bool {
return len(userAgents) == 1 && (userAgents[0] == "grpc-go/1.15.0" || userAgents[0] == "grpc-go/1.10.0")
}