feat: Enable configuration of ignored and expected HTTP status code errors with environment variables (#2487)

* Environment override for expected error status codes

* Ignored status codes from env var

* Improve unit tests

* List->Enumerable, save on ToList() calls

* Add a test for range setting via env var

Author: nr-ahemsath

src/Agent/NewRelic/Agent/Core/Configuration/DefaultConfiguration.cs

@@ -2382,7 +2382,7 @@ private static T ServerOverrides<T>(T server, T local) where T : class
             return server ?? local;
         }
 
-        private List<string> EnvironmentOverrides(List<string> local, params string[] environmentVariableNames)
+        private IEnumerable<string> EnvironmentOverrides(IEnumerable<string> local, params string[] environmentVariableNames)
         {
             var envValue = (environmentVariableNames ?? Enumerable.Empty<string>())
                 .Select(_environment.GetEnvironmentVariable)
@@ -2628,10 +2628,10 @@ private void ParseExpectedErrorConfigurations()
             var expectedStatusCodesArrayLocal = _localConfiguration.errorCollector.expectedStatusCodes?.Split(StringSeparators.Comma, StringSplitOptions.RemoveEmptyEntries);
             var expectedStatusCodesArrayServer = _serverConfiguration.RpmConfig.ErrorCollectorExpectedStatusCodes;
 
-            var expectedStatusCodesArray = ServerOverrides(expectedStatusCodesArrayServer, expectedStatusCodesArrayLocal);
+            var expectedStatusCodesArray = EnvironmentOverrides(ServerOverrides(expectedStatusCodesArrayServer, expectedStatusCodesArrayLocal), "NEW_RELIC_ERROR_COLLECTOR_EXPECTED_ERROR_CODES");
 
             ExpectedStatusCodes = ParseExpectedStatusCodesArray(expectedStatusCodesArray);
-            ExpectedErrorStatusCodesForAgentSettings = expectedStatusCodesArray ?? new string[0];
+            ExpectedErrorStatusCodesForAgentSettings = expectedStatusCodesArray ?? new List<string>();
 
             ExpectedErrorsConfiguration = new ReadOnlyDictionary<string, IEnumerable<string>>(expectedErrorInfo);
             ExpectedErrorMessagesForAgentSettings = new ReadOnlyDictionary<string, IEnumerable<string>>(expectedMessages);
@@ -2677,7 +2677,7 @@ private void ParseIgnoreErrorConfigurations()
                 }
             }
 
-            var ignoreStatusCodes = _serverConfiguration.RpmConfig.ErrorCollectorStatusCodesToIgnore;
+            IEnumerable<string> ignoreStatusCodes = EnvironmentOverrides(_serverConfiguration.RpmConfig.ErrorCollectorStatusCodesToIgnore, "NEW_RELIC_ERROR_COLLECTOR_IGNORE_ERROR_CODES");
             if (ignoreStatusCodes == null)
             {
                 ignoreStatusCodes = _localConfiguration.errorCollector.ignoreStatusCodes.code

tests/Agent/UnitTests/Core.UnitTest/Configuration/DefaultConfigurationTests.cs

@@ -999,19 +999,44 @@ public string IgnoreErrorsAndIgnoreClassesCombineTests(string[] ignoreClasses, s
             return string.Join(",", _defaultConfig.IgnoreErrorsConfiguration.Keys);
         }
 
-        [TestCase("401", new[] { "405" }, ExpectedResult = new[] { "405" })]
-        [TestCase("401", new string[0], ExpectedResult = new string[0])]
-        [TestCase("401", null, ExpectedResult = new[] { "401" })]
-        public string[] ExpectedStatusCodesSetFromLocalAndServerOverrides(string local, string[] server)
+        [TestCase("401", new[] { "405" }, null,           ExpectedResult = new[] { "405" })]
+        [TestCase("401", new string[0],   null,           ExpectedResult = new string[0])]
+        [TestCase("401", null,            null,           ExpectedResult = new[] { "401" })]
+        [TestCase(null,  null,            "401",          ExpectedResult = new[] { "401" })]
+        [TestCase(null,  new[] { "405" }, "401",          ExpectedResult = new[] { "401" })]
+        [TestCase("402", new string[0],   "401",          ExpectedResult = new[] { "401" })]
+        [TestCase("402", new string[0],   "401, 503",     ExpectedResult = new[] { "401", "503" })]
+        [TestCase("402", new string[0],   "401, 500-505", ExpectedResult = new[] { "401", "500-505" })]
+        public string[] ExpectedStatusCodesSetFromLocalServerAndEnvironmentOverrides(string local, string[] server, string env)
         {
             _serverConfig.RpmConfig.ErrorCollectorExpectedStatusCodes = server;
             _localConfig.errorCollector.expectedStatusCodes = (local);
+            Mock.Arrange(() => _environment.GetEnvironmentVariable("NEW_RELIC_ERROR_COLLECTOR_EXPECTED_ERROR_CODES")).Returns(env);
 
             CreateDefaultConfiguration();
 
             return _defaultConfig.ExpectedErrorStatusCodesForAgentSettings.ToArray();
         }
 
+        [TestCase(new[] { 401f },   new[] { "405" }, null,         ExpectedResult = new[] { "405" })]
+        [TestCase(new[] { 401f },   new string[0],   null,         ExpectedResult = new string[0])]
+        [TestCase(new[] { 401f },   null,            null,         ExpectedResult = new[] { "401" })]
+        [TestCase(new[] { 401.5f }, null,            null,         ExpectedResult = new[] { "401.5" })]
+        [TestCase(new float[0],     null,            "401",        ExpectedResult = new[] { "401" })]
+        [TestCase(new float[0],     new[] { "405" }, "401",        ExpectedResult = new[] { "401" })]
+        [TestCase(new[] { 401f },   new string[0],   "402",        ExpectedResult = new[] { "402" })]
+        [TestCase(new[] { 401f },   new string[0],   "401.5, 503", ExpectedResult = new[] { "401.5", "503" })]
+        public string[] IgnoredStatusCodesSetFromLocalServerAndEnvironmentOverrides(float[] local, string[] server, string env)
+        {
+            _serverConfig.RpmConfig.ErrorCollectorStatusCodesToIgnore = server;
+            _localConfig.errorCollector.ignoreStatusCodes.code = (local.ToList());
+            Mock.Arrange(() => _environment.GetEnvironmentVariable("NEW_RELIC_ERROR_COLLECTOR_IGNORE_ERROR_CODES")).Returns(env);
+
+            CreateDefaultConfiguration();
+
+            return _defaultConfig.HttpStatusCodesToIgnore.ToArray();
+        }
+
         [TestCase("401-404", new string[] { "401.5", "402.3" }, new bool[] { false, false })] //does not support full status codes
         [TestCase("400,401,404", new string[] { "400", "401", "402", "403", "404" }, new bool[] { true, true, false, false, true })]
         [TestCase("400, 401 ,404", new string[] { "400", "401", "402", "403", "404" }, new bool[] { true, true, false, false, true })]