ooni-probe-cli/internal/errorsx/resolver.go
Simone Basso 83440cf110
refactor: split errorsx in good and legacy (#477)
The legacy part for now is internal/errorsx. It will stay there until
I figure out whether it also needs some extra bug fixing.

The good part is now in internal/netxlite/errorsx and contains all the
logic for mapping errors. We need to further improve upon this logic
by writing more thorough integration tests for QUIC.

We also need to copy the various dialer, conn, etc adapters that set
errors. We will put them inside netxlite and we will generate errors in
a way that is less crazy with respect to the major operation. (The
idea is to always wrap, given that now we measure in an incremental way
and we don't measure every operation together.)

Part of https://github.com/ooni/probe/issues/1591
2021-09-07 17:09:30 +02:00

57 lines
1.4 KiB
Go

package errorsx
import (
"context"
"github.com/ooni/probe-cli/v3/internal/netxlite/errorsx"
)
// Resolver is a DNS resolver. The *net.Resolver used by Go implements
// this interface, but other implementations are possible.
type Resolver interface {
// LookupHost resolves a hostname to a list of IP addresses.
LookupHost(ctx context.Context, hostname string) (addrs []string, err error)
}
// ErrorWrapperResolver is a Resolver that knows about wrapping errors.
type ErrorWrapperResolver struct {
Resolver
}
var _ Resolver = &ErrorWrapperResolver{}
// LookupHost implements Resolver.LookupHost
func (r *ErrorWrapperResolver) LookupHost(ctx context.Context, hostname string) ([]string, error) {
addrs, err := r.Resolver.LookupHost(ctx, hostname)
err = SafeErrWrapperBuilder{
Classifier: errorsx.ClassifyResolverError,
Error: err,
Operation: errorsx.ResolveOperation,
}.MaybeBuild()
return addrs, err
}
type resolverNetworker interface {
Network() string
}
// Network implements Resolver.Network.
func (r *ErrorWrapperResolver) Network() string {
if rn, ok := r.Resolver.(resolverNetworker); ok {
return rn.Network()
}
return "errorWrapper"
}
type resolverAddresser interface {
Address() string
}
// Address implements Resolver.Address.
func (r *ErrorWrapperResolver) Address() string {
if ra, ok := r.Resolver.(resolverAddresser); ok {
return ra.Address()
}
return ""
}