dashboard, p2p, vendor: visualize peers (#19247)

* dashboard, p2p: visualize peers

* dashboard: change scale to green to red

vendor/github.com/oschwald/maxminddb-golang/traverse.go

@@ -0,0 +1,108 @@
+package maxminddb
+
+import "net"
+
+// Internal structure used to keep track of nodes we still need to visit.
+type netNode struct {
+	ip      net.IP
+	bit     uint
+	pointer uint
+}
+
+// Networks represents a set of subnets that we are iterating over.
+type Networks struct {
+	reader   *Reader
+	nodes    []netNode // Nodes we still have to visit.
+	lastNode netNode
+	err      error
+}
+
+// Networks returns an iterator that can be used to traverse all networks in
+// the database.
+//
+// Please note that a MaxMind DB may map IPv4 networks into several locations
+// in in an IPv6 database. This iterator will iterate over all of these
+// locations separately.
+func (r *Reader) Networks() *Networks {
+	s := 4
+	if r.Metadata.IPVersion == 6 {
+		s = 16
+	}
+	return &Networks{
+		reader: r,
+		nodes: []netNode{
+			{
+				ip: make(net.IP, s),
+			},
+		},
+	}
+}
+
+// Next prepares the next network for reading with the Network method. It
+// returns true if there is another network to be processed and false if there
+// are no more networks or if there is an error.
+func (n *Networks) Next() bool {
+	for len(n.nodes) > 0 {
+		node := n.nodes[len(n.nodes)-1]
+		n.nodes = n.nodes[:len(n.nodes)-1]
+
+		for {
+			if node.pointer < n.reader.Metadata.NodeCount {
+				ipRight := make(net.IP, len(node.ip))
+				copy(ipRight, node.ip)
+				if len(ipRight) <= int(node.bit>>3) {
+					n.err = newInvalidDatabaseError(
+						"invalid search tree at %v/%v", ipRight, node.bit)
+					return false
+				}
+				ipRight[node.bit>>3] |= 1 << (7 - (node.bit % 8))
+
+				rightPointer, err := n.reader.readNode(node.pointer, 1)
+				if err != nil {
+					n.err = err
+					return false
+				}
+
+				node.bit++
+				n.nodes = append(n.nodes, netNode{
+					pointer: rightPointer,
+					ip:      ipRight,
+					bit:     node.bit,
+				})
+
+				node.pointer, err = n.reader.readNode(node.pointer, 0)
+				if err != nil {
+					n.err = err
+					return false
+				}
+
+			} else if node.pointer > n.reader.Metadata.NodeCount {
+				n.lastNode = node
+				return true
+			} else {
+				break
+			}
+		}
+	}
+
+	return false
+}
+
+// Network returns the current network or an error if there is a problem
+// decoding the data for the network. It takes a pointer to a result value to
+// decode the network's data into.
+func (n *Networks) Network(result interface{}) (*net.IPNet, error) {
+	if err := n.reader.retrieveData(n.lastNode.pointer, result); err != nil {
+		return nil, err
+	}
+
+	return &net.IPNet{
+		IP:   n.lastNode.ip,
+		Mask: net.CIDRMask(int(n.lastNode.bit), len(n.lastNode.ip)*8),
+	}, nil
+}
+
+// Err returns an error, if any, that was encountered during iteration.
+func (n *Networks) Err() error {
+	return n.err
+}