From caf5cf80fa84f57708b3eadec9cc35a63b448dd6 Mon Sep 17 00:00:00 2001
From: jlukawska <jolanta.lukawska@gmail.com>
Date: Mon, 16 Dec 2019 21:19:31 +0100
Subject: [PATCH] #683 validate if there are duplicated placeholders in
 UpstreamPathTemplate

---
 .../FileConfigurationFluentValidator.cs       | 13 ++++++++++
 .../FileConfigurationFluentValidatorTests.cs  | 26 +++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/src/Ocelot/Configuration/Validator/FileConfigurationFluentValidator.cs b/src/Ocelot/Configuration/Validator/FileConfigurationFluentValidator.cs
index add4fe0bb..e2f7f24d1 100644
--- a/src/Ocelot/Configuration/Validator/FileConfigurationFluentValidator.cs
+++ b/src/Ocelot/Configuration/Validator/FileConfigurationFluentValidator.cs
@@ -9,6 +9,7 @@
     using System;
     using System.Collections.Generic;
     using System.Linq;
+    using System.Text.RegularExpressions;
     using System.Threading.Tasks;
 
     public class FileConfigurationFluentValidator : AbstractValidator<FileConfiguration>, IConfigurationValidator
@@ -35,6 +36,10 @@ public FileConfigurationFluentValidator(IServiceProvider provider, ReRouteFluent
                 .Must((config, reRoute) => HaveServiceDiscoveryProviderRegistered(reRoute, config.GlobalConfiguration.ServiceDiscoveryProvider))
                 .WithMessage((config, reRoute) => $"Unable to start Ocelot, errors are: Unable to start Ocelot because either a ReRoute or GlobalConfiguration are using ServiceDiscoveryOptions but no ServiceDiscoveryFinderDelegate has been registered in dependency injection container. Are you missing a package like Ocelot.Provider.Consul and services.AddConsul() or Ocelot.Provider.Eureka and services.AddEureka()?");
 
+            RuleForEach(configuration => configuration.ReRoutes)
+                .Must((config, reRoute) => IsPlaceholderNotDuplicatedIn(reRoute.UpstreamPathTemplate))
+                .WithMessage((config, reRoute) => $"{nameof(reRoute)} {reRoute.UpstreamPathTemplate} has duplicated placeholder");
+
             RuleFor(configuration => configuration.GlobalConfiguration.ServiceDiscoveryProvider)
                 .Must(HaveServiceDiscoveryProviderRegistered)
                 .WithMessage((config, reRoute) => $"Unable to start Ocelot, errors are: Unable to start Ocelot because either a ReRoute or GlobalConfiguration are using ServiceDiscoveryOptions but no ServiceDiscoveryFinderDelegate has been registered in dependency injection container. Are you missing a package like Ocelot.Provider.Consul and services.AddConsul() or Ocelot.Provider.Eureka and services.AddEureka()?");
@@ -109,6 +114,14 @@ private bool AllReRoutesForAggregateExist(FileAggregateReRoute fileAggregateReRo
             return reRoutesForAggregate.Count() == fileAggregateReRoute.ReRouteKeys.Count;
         }
 
+        private bool IsPlaceholderNotDuplicatedIn(string upstreamPathTemplate)
+        {
+            Regex regExPlaceholder = new Regex("{[^}]+}");
+            var matches = regExPlaceholder.Matches(upstreamPathTemplate);
+            var upstreamPathPlaceholders = matches.Select(m => m.Value);
+            return upstreamPathPlaceholders.Count() == upstreamPathPlaceholders.Distinct().Count();
+        }
+
         private static bool DoesNotContainReRoutesWithSpecificRequestIdKeys(FileAggregateReRoute fileAggregateReRoute,
             List<FileReRoute> reRoutes)
         {
diff --git a/test/Ocelot.UnitTests/Configuration/Validation/FileConfigurationFluentValidatorTests.cs b/test/Ocelot.UnitTests/Configuration/Validation/FileConfigurationFluentValidatorTests.cs
index 943001fc6..7055c1ad6 100644
--- a/test/Ocelot.UnitTests/Configuration/Validation/FileConfigurationFluentValidatorTests.cs
+++ b/test/Ocelot.UnitTests/Configuration/Validation/FileConfigurationFluentValidatorTests.cs
@@ -1341,6 +1341,32 @@ public void configuration_is_not_valid_when_host_and_port_is_empty()
                 .BDDfy();
         }
 
+        [Fact]
+        public void configuration_is_invalid_when_placeholder_is_used_twice_in_upstream_path_template()
+        {
+            this.Given(x => x.GivenAConfiguration(new FileConfiguration
+            {
+                ReRoutes = new List<FileReRoute>
+                {
+                    new FileReRoute
+                    {
+                        DownstreamPathTemplate = "/bar/{everything}",
+                        DownstreamScheme = "http",
+                        DownstreamHostAndPorts = new List<FileHostAndPort> 
+                        { 
+                            new FileHostAndPort() { Host = "a.b.cd" },
+                        },
+                        UpstreamPathTemplate = "/foo/bar/{everything}/{everything}",
+                        UpstreamHttpMethod = new List<string> { "Get" },
+                    },
+                },
+            }))
+                .When(x => x.WhenIValidateTheConfiguration())
+                .Then(x => x.ThenTheResultIsNotValid())
+                .And(x => x.ThenTheErrorMessageAtPositionIs(0, "reRoute /foo/bar/{everything}/{everything} has duplicated placeholder"))
+                .BDDfy();
+        }
+
         private void GivenAConfiguration(FileConfiguration fileConfiguration)
         {
             _fileConfiguration = fileConfiguration;