package finder import ( "fmt" "strings" "sync" "github.com/hashicorp/consul/api" ) // Finder finds intentions by a src/dst exact match. There is currently // no direct API to do this so this struct downloads all intentions and // caches them once, and searches in-memory for this. For now this works since // even with a very large number of intentions, the size of the data gzipped // over HTTP will be relatively small. // // The Finder will only download the intentions one time. This struct is // not expected to be used over a long period of time. Though it may be // reused multile times, the intentions list is only downloaded once. type Finder struct { // Client is the API client to use for any requests. Client *api.Client lock sync.Mutex ixns []*api.Intention // cached list of intentions } // ID returns the intention ID for the given CLI args. An error is returned // if args is not 1 or 2 elements. func (f *Finder) IDFromArgs(args []string) (string, error) { switch len(args) { case 1: return args[0], nil case 2: ixn, err := f.Find(args[0], args[1]) if err != nil { return "", err } if ixn == nil { return "", fmt.Errorf( "Intention with source %q and destination %q not found.", args[0], args[1]) } return ixn.ID, nil default: return "", fmt.Errorf("command requires exactly 1 or 2 arguments") } } // Find finds the intention that matches the given src and dst. This will // return nil when the result is not found. func (f *Finder) Find(src, dst string) (*api.Intention, error) { src = StripDefaultNS(src) dst = StripDefaultNS(dst) f.lock.Lock() defer f.lock.Unlock() // If the list of ixns is nil, then we haven't fetched yet, so fetch if f.ixns == nil { ixns, _, err := f.Client.Connect().Intentions(nil) if err != nil { return nil, err } f.ixns = ixns } // Go through the intentions and find an exact match for _, ixn := range f.ixns { if ixn.SourceString() == src && ixn.DestinationString() == dst { return ixn, nil } } return nil, nil } // StripDefaultNS strips the default namespace from an argument. For now, // the API and lookups strip this value from string output so we strip it. func StripDefaultNS(v string) string { if idx := strings.IndexByte(v, '/'); idx > 0 { if v[:idx] == api.IntentionDefaultNamespace { return v[idx+1:] } } return v }