func TestRtt_sortNodesByDistanceFrom(t *testing.T) {
dir, server := testServer(t)
defer os.RemoveAll(dir)
defer server.Shutdown()
codec := rpcClient(t, server)
defer codec.Close()
testutil.WaitForLeader(t, server.RPC, "dc1")
seedCoordinates(t, codec, server)
nodes := structs.Nodes{
&structs.Node{Node: "apple"},
&structs.Node{Node: "node1"},
&structs.Node{Node: "node2"},
&structs.Node{Node: "node3"},
&structs.Node{Node: "node4"},
&structs.Node{Node: "node5"},
}
// The zero value for the source should not trigger any sorting.
var source structs.QuerySource
if err := server.sortNodesByDistanceFrom(source, nodes); err != nil {
t.Fatalf("err: %v", err)
}
verifyNodeSort(t, nodes, "apple,node1,node2,node3,node4,node5")
// Same for a source in some other DC.
source.Node = "node1"
source.Datacenter = "dc2"
if err := server.sortNodesByDistanceFrom(source, nodes); err != nil {
t.Fatalf("err: %v", err)
}
verifyNodeSort(t, nodes, "apple,node1,node2,node3,node4,node5")
// Same for a source node in our DC that we have no coordinate for.
source.Node = "apple"
source.Datacenter = "dc1"
if err := server.sortNodesByDistanceFrom(source, nodes); err != nil {
t.Fatalf("err: %v", err)
}
verifyNodeSort(t, nodes, "apple,node1,node2,node3,node4,node5")
// Set source to legit values relative to node1 but disable coordinates.
source.Node = "node1"
source.Datacenter = "dc1"
server.config.DisableCoordinates = true
if err := server.sortNodesByDistanceFrom(source, nodes); err != nil {
t.Fatalf("err: %v", err)
}
verifyNodeSort(t, nodes, "apple,node1,node2,node3,node4,node5")
// Now enable coordinates and sort relative to node1, note that apple
// doesn't have any seeded coordinate info so it should end up at the
// end, despite its lexical hegemony.
server.config.DisableCoordinates = false
if err := server.sortNodesByDistanceFrom(source, nodes); err != nil {
t.Fatalf("err: %v", err)
}
verifyNodeSort(t, nodes, "node1,node4,node5,node2,node3,apple")
}
// parseSource is used to parse the ?near=<node> query parameter, used for
// sorting by RTT based on a source node. We set the source's DC to the target
// DC in the request, if given, or else the agent's DC.
func (s *HTTPServer) parseSource(req *http.Request, source *structs.QuerySource) {
s.parseDC(req, &source.Datacenter)
if node := req.URL.Query().Get("near"); node != "" {
if node == "_agent" {
source.Node = s.agent.config.NodeName
} else {
source.Node = node
}
}
}
func TestRtt_sortNodesByDistanceFrom_CheckServiceNodes(t *testing.T) {
dir, server := testServer(t)
defer os.RemoveAll(dir)
defer server.Shutdown()
codec := rpcClient(t, server)
defer codec.Close()
testutil.WaitForLeader(t, server.RPC, "dc1")
seedCoordinates(t, codec, server)
nodes := structs.CheckServiceNodes{
structs.CheckServiceNode{Node: &structs.Node{Node: "apple"}},
structs.CheckServiceNode{Node: &structs.Node{Node: "node1"}},
structs.CheckServiceNode{Node: &structs.Node{Node: "node2"}},
structs.CheckServiceNode{Node: &structs.Node{Node: "node3"}},
structs.CheckServiceNode{Node: &structs.Node{Node: "node4"}},
structs.CheckServiceNode{Node: &structs.Node{Node: "node5"}},
}
// Now sort relative to node1, note that apple doesn't have any
// seeded coordinate info so it should end up at the end, despite
// its lexical hegemony.
var source structs.QuerySource
source.Node = "node1"
source.Datacenter = "dc1"
if err := server.sortNodesByDistanceFrom(source, nodes); err != nil {
t.Fatalf("err: %v", err)
}
verifyCheckServiceNodeSort(t, nodes, "node1,node4,node5,node2,node3,apple")
// Try another sort from node2. Note that node5 and node3 are the
// same distance away so the stable sort should preserve the order
// they were in from the previous sort.
source.Node = "node2"
source.Datacenter = "dc1"
if err := server.sortNodesByDistanceFrom(source, nodes); err != nil {
t.Fatalf("err: %v", err)
}
verifyCheckServiceNodeSort(t, nodes, "node2,node5,node3,node4,node1,apple")
// Let's exercise the stable sort explicitly to make sure we didn't
// just get lucky.
nodes[1], nodes[2] = nodes[2], nodes[1]
if err := server.sortNodesByDistanceFrom(source, nodes); err != nil {
t.Fatalf("err: %v", err)
}
verifyCheckServiceNodeSort(t, nodes, "node2,node3,node5,node4,node1,apple")
}