GH-3798: Add HTTP prepared query near=_ip test

Also fixed an issue where we need to have the X-Forwarded-For header processed before the RemoteAddr. This shouldn’t have any functional difference for prod code but for mocked request objects it allows them to work.

agent/http.go

@@ -499,22 +499,22 @@ func (s *HTTPServer) parseToken(req *http.Request, token *string) {
 }
 
 func sourceAddrFromRequest(req *http.Request) (string, error) {
+	forwardHost := req.Header.Get("X-Forwarded-For")
+	forwardIp := net.ParseIP(forwardHost)
+	if forwardIp != nil {
+		return forwardIp.String(), nil
+	} 
+	
 	host, _, err := net.SplitHostPort(req.RemoteAddr)
 	if err != nil {
 		return "", err
 	}
 
 	ip := net.ParseIP(host)
-	if ip == nil {
-		return "", fmt.Errorf("Could not get IP from request")
-	}
-
-	forwardHost := req.Header.Get("X-Forwarded-For")
-	forwardIp := net.ParseIP(forwardHost)
-	if forwardIp != nil {
-		return forwardIp.String(), nil
-	} else {
+	if ip != nil {
 		return ip.String(), nil
+	} else {
+		return "", fmt.Errorf("Could not get remote IP from HTTP Request")
 	}
 }
 

agent/prepared_query_endpoint_test.go

@@ -324,6 +324,63 @@ func TestPreparedQuery_Execute(t *testing.T) {
 			t.Fatalf("bad: %v", r)
 		}
 	})
+	
+	t.Run("", func(t *testing.T) {
+		a := NewTestAgent(t.Name(), "")
+		defer a.Shutdown()
+
+		m := MockPreparedQuery{
+			executeFn: func(args *structs.PreparedQueryExecuteRequest, reply *structs.PreparedQueryExecuteResponse) error {
+				expected := &structs.PreparedQueryExecuteRequest{
+					Datacenter:    "dc1",
+					QueryIDOrName: "my-id",
+					Limit:         5,
+					Source: structs.QuerySource{
+						Datacenter: "dc1",
+						Node: "_ip",
+						Ip:         "127.0.0.1",
+					},
+					Agent: structs.QuerySource{
+						Datacenter: a.Config.Datacenter,
+						Node:       a.Config.NodeName,
+					},
+					QueryOptions: structs.QueryOptions{
+						Token:             "my-token",
+						RequireConsistent: true,
+					},
+				}
+				if !reflect.DeepEqual(args, expected) {
+					t.Fatalf("bad: %v", args)
+				}
+
+				// Just set something so we can tell this is returned.
+				reply.Failovers = 99
+				return nil
+			},
+		}
+		if err := a.registerEndpoint("PreparedQuery", &m); err != nil {
+			t.Fatalf("err: %v", err)
+		}
+
+		body := bytes.NewBuffer(nil)
+		req, _ := http.NewRequest("GET", "/v1/query/my-id/execute?token=my-token&consistent=true&near=_ip&limit=5", body)
+		req.Header.Add("X-Forwarded-For", "127.0.0.1")
+		resp := httptest.NewRecorder()
+		obj, err := a.srv.PreparedQuerySpecific(resp, req)
+		if err != nil {
+			t.Fatalf("err: %v", err)
+		}
+		if resp.Code != 200 {
+			t.Fatalf("bad code: %d", resp.Code)
+		}
+		r, ok := obj.(structs.PreparedQueryExecuteResponse)
+		if !ok {
+			t.Fatalf("unexpected: %T", obj)
+		}
+		if r.Failovers != 99 {
+			t.Fatalf("bad: %v", r)
+		}
+	})
 
 	// Ensure the proper params are set when no special args are passed
 	t.Run("", func(t *testing.T) {