feat(peers): fix limit/offset bugs, add sending output to less when…

… listing peer cache

While working on offset and limit for `qri peers list`, I realized that paginating through the list of peers doesn't really make sense, because to generate the peers list we range through a map, not a slice, we get a different order each time.

We can talk about whether we want to make this list ordered, but for now, I thought it might be a good place to try to stdout to `less`, rather then return the output to the terminal.

So, if you look for your cached peers, qri will send you to `less` that displays your cached peers.

actions/peers.go

@@ -34,11 +34,15 @@ func ListPeers(node *p2p.QriNode, limit, offset int, onlineOnly bool) ([]*config
 		return nil, fmt.Errorf("error listing peers: %s", err.Error())
 	}
 
-	if len(ps) == 0 {
+	if len(ps) == 0 || offset >= len(ps) {
 		return []*config.ProfilePod{}, nil
 	}
 
 	for _, pro := range ps {
+		if offset > 0 {
+			offset--
+			continue
+		}
 		if len(peers) >= limit {
 			break
 		}

cmd/peers.go

@@ -1,8 +1,10 @@
 package cmd
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
+	"os/exec"
 
 	"github.com/ghodss/yaml"
 	"github.com/qri-io/ioes"
@@ -218,9 +220,8 @@ func (o *PeersOptions) List() (err error) {
 			printSuccess(o.Out, "%d.\t%s", i+1, p)
 		}
 	} else {
-
 		// if we don't have an RPC client, assume we're not connected
-		if o.UsingRPC && !o.Cached {
+		if !o.UsingRPC && !o.Cached {
 			printInfo(o.Out, "qri not connected, listing cached peers")
 			o.Cached = true
 		}
@@ -235,10 +236,31 @@ func (o *PeersOptions) List() (err error) {
 			return err
 		}
 
+		if o.Cached {
+			// if cached, print to less
+			// because the list of peers is non deterministic
+			// it make sense to try out printing to less here
+			// where limit and offset don't mean as much
+			buf := bytes.Buffer{}
+			fmt.Fprintln(&buf, "Cached Qri Peers List:\n")
+			for i, peer := range res {
+				printPeerInfoNoColor(&buf, i, peer)
+			}
+			less := exec.Command("less")
+			less.Stdin = &buf
+			less.Stdout = o.Out
+
+			if err := less.Run(); err != nil {
+				return err
+			}
+			return nil
+		}
+
 		fmt.Fprintln(o.Out, "")
 		for i, peer := range res {
 			printPeerInfo(o.Out, i, peer)
 		}
+
 	}
 	return nil
 }

cmd/print.go

@@ -181,6 +181,19 @@ func printPeerInfo(w io.Writer, i int, p *config.ProfilePod) {
 	fmt.Fprintln(w, "")
 }
 
+func printPeerInfoNoColor(w io.Writer, i int, p *config.ProfilePod) {
+	if p.Online {
+		fmt.Fprintf(w, "%s | %s\n", p.Peername, "online")
+	} else {
+		fmt.Fprintf(w, "%s\n", p.Peername)
+	}
+	fmt.Fprintf(w, "profile ID: %s\n", p.ID)
+	if len(p.NetworkAddrs) > 0 {
+		fmt.Fprintf(w, "address:    %s\n", p.NetworkAddrs[0])
+	}
+	fmt.Fprintln(w, "")
+}
+
 func printResults(w io.Writer, r *dataset.Structure, data []byte, format dataset.DataFormat) {
 	switch format {
 	case dataset.JSONDataFormat: