Merge pull request #32 from datalust/dev

2.1.0 Release

Author: nblumhardt

README.md

@@ -6,7 +6,7 @@ Periodically GET an HTTP resource and write response metrics to Seq. These can t
 
 ### Getting started
 
-1. The app requires Seq 5.1 or newer
+1. The app requires Seq 2020.4 or newer
 2. Navigate to _Settings_ > _Apps_ and select _Install from NuGet_
 3. Install the app with package id _Seq.Input.HealthCheck_
 4. Back on the _Apps_ screen, choose _Add Instance_
@@ -16,4 +16,3 @@ Periodically GET an HTTP resource and write response metrics to Seq. These can t
    - if the URL is an HTTPS URL, the Seq server must trust the SSL certificate used by the server
    - the response will be fully downloaded on every check, so ideally the resource won't be more than a few kB
 7. Enter a probing interval in seconds; each event is stored internally in Seq, so be aware that shorter intervals will consume more space
-

appveyor.yml

@@ -9,7 +9,7 @@ artifacts:
 deploy:
 - provider: NuGet
   api_key:
-    secure: bkES4Ho0Cs/3Ws1PP7fYfSZop6K8VfqAAEFUR25eQRCJXVDPa+atx3alsaMhzVdo
+    secure: 8a7m6Xbn2SER7teqWvpYqff2MMeeFKVgU1UertfVosvlz3vhmrLZKOB9mtEmcnIL
   skip_symbols: true
   on:
     branch: /^(main|dev)$/
@@ -19,4 +19,4 @@ deploy:
   artifact: /Seq.Input.HealthCheck.*\.nupkg/
   tag: v$(appveyor_build_version)
   on:
-    branch: master
+    branch: main

src/Seq.Input.HealthCheck/Data/JsonDataExtractor.cs

@@ -16,59 +16,58 @@
 using System.IO;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
-using Serilog.Expressions;
+using Seq.Syntax.Expressions;
 using Serilog.Formatting.Compact.Reader;
 using Serilog.Formatting.Json;
 
-namespace Seq.Input.HealthCheck.Data
+namespace Seq.Input.HealthCheck.Data;
+
+public class JsonDataExtractor
 {
-    public class JsonDataExtractor
+    static readonly JsonValueFormatter ValueFormatter = new("$type");
+    static readonly JsonSerializer Serializer = JsonSerializer.Create(new JsonSerializerSettings
     {
-        static readonly JsonValueFormatter ValueFormatter = new("$type");
-        static readonly JsonSerializer Serializer = JsonSerializer.Create(new JsonSerializerSettings
-        {
-            DateParseHandling = DateParseHandling.None
-        });
+        DateParseHandling = DateParseHandling.None
+    });
 
-        readonly Func<JToken?, JToken> _extract;
+    readonly Func<JToken?, JToken> _extract;
 
-        public JsonDataExtractor(string expression)
+    public JsonDataExtractor(string expression)
+    {
+        if (expression == "@Properties")
+        {
+            _extract = v => v ?? JValue.CreateNull();
+        }
+        else
         {
-            if (expression == "@Properties")
-            {
-                _extract = v => v ?? JValue.CreateNull();
-            }
-            else
-            {
-                var expr = SerilogExpression.Compile(expression, nameResolver: new SeqSyntaxNameResolver());
-                _extract = v => {
-                    if (v is not JObject obj)
-                        throw new ArgumentException("Data value extraction requires a JSON object response.");
+            var expr = SerilogExpression.Compile(expression, nameResolver: new SeqSyntaxNameResolver());
+            _extract = v => {
+                if (v is not JObject obj)
+                    throw new ArgumentException("Data value extraction requires a JSON object response.");
 
-                    if (!obj.ContainsKey("@t"))
-                        obj["@t"] = DateTime.UtcNow.ToString("o");
+                if (!obj.ContainsKey("@t"))
+                    obj["@t"] = DateTime.UtcNow.ToString("o");
 
-                    var le = LogEventReader.ReadFromJObject(obj);
+                var le = LogEventReader.ReadFromJObject(obj);
 
-                    var value = expr(le);
+                var value = expr(le);
 
-                    // `null` here means "undefined", but for most purposes this substitution is convenient.
-                    if (value == null)
-                        return JValue.CreateNull();
+                // `null` here means "undefined", but for most purposes this substitution is convenient.
+                if (value == null)
+                    return JValue.CreateNull();
 
-                    var sw = new StringWriter();
-                    ValueFormatter.Format(value, sw);
-                    return Serializer.Deserialize<JToken>(
-                        new JsonTextReader(new StringReader(sw.ToString())))!;
-                };
-            }
+                var sw = new StringWriter();
+                ValueFormatter.Format(value, sw);
+                return Serializer.Deserialize<JToken>(
+                    new JsonTextReader(new StringReader(sw.ToString())))!;
+            };
         }
+    }
 
-        public JToken ExtractData(TextReader json)
-        {
-            if (json == null) throw new ArgumentNullException(nameof(json));
-            var document = Serializer.Deserialize<JToken>(new JsonTextReader(json));
-            return _extract(document);
-        }
+    public JToken ExtractData(TextReader json)
+    {
+        if (json == null) throw new ArgumentNullException(nameof(json));
+        var document = Serializer.Deserialize<JToken>(new JsonTextReader(json));
+        return _extract(document);
     }
-}
+}

src/Seq.Input.HealthCheck/Data/SeqSyntaxNameResolver.cs

@@ -2,45 +2,28 @@
 using System.Diagnostics.CodeAnalysis;
 using System.Reflection;
 using Serilog.Events;
-using Serilog.Expressions;
+using Seq.Syntax.Expressions;
 
-namespace Seq.Input.HealthCheck.Data
+namespace Seq.Input.HealthCheck.Data;
+
+public class SeqSyntaxNameResolver: NameResolver
 {
-    public class SeqSyntaxNameResolver: NameResolver
+    // ReSharper disable once UnusedMember.Global
+    // ReSharper disable once ReturnTypeCanBeNotNullable
+    public static LogEventPropertyValue? Has(LogEventPropertyValue? value)
     {
-        // ReSharper disable once UnusedMember.Global
-        // ReSharper disable once ReturnTypeCanBeNotNullable
-        public static LogEventPropertyValue? Has(LogEventPropertyValue? value)
-        {
-            return new ScalarValue(value != null);
-        }
+        return new ScalarValue(value != null);
+    }
 
-        public override bool TryResolveFunctionName(string name, [NotNullWhen(true)] out MethodInfo? implementation)
+    public override bool TryResolveFunctionName(string name, [NotNullWhen(true)] out MethodInfo? implementation)
+    {
+        if ("Has".Equals(name, StringComparison.OrdinalIgnoreCase))
         {
-            if ("Has".Equals(name, StringComparison.OrdinalIgnoreCase))
-            {
-                implementation = GetType().GetMethod("Has", BindingFlags.Static | BindingFlags.Public)!;
-                return true;
-            }
-
-            implementation = null;
-            return false;
+            implementation = GetType().GetMethod("Has", BindingFlags.Static | BindingFlags.Public)!;
+            return true;
         }
 
-        public override bool TryResolveBuiltInPropertyName(string alias, [NotNullWhen(true)] out string? target)
-        {
-            target = alias switch
-            {
-                "Exception" => "x",
-                "Level" => "l",
-                "Message" => "m",
-                "MessageTemplate" => "mt",
-                "Properties" => "p",
-                "Timestamp" => "t",
-                _ => null
-            };
-        
-            return target != null;
-        }
+        implementation = null;
+        return false;
     }
 }

src/Seq.Input.HealthCheck/HealthCheckInput.cs

@@ -19,97 +19,105 @@
 using Seq.Apps;
 using Seq.Input.HealthCheck.Data;
 using Seq.Input.HealthCheck.Util;
+// ReSharper disable UnusedType.Global
 // ReSharper disable MemberCanBePrivate.Global
 // ReSharper disable UnusedAutoPropertyAccessor.Global
 // ReSharper disable AutoPropertyCanBeMadeGetOnly.Global
 
-namespace Seq.Input.HealthCheck
+namespace Seq.Input.HealthCheck;
+
+[SeqApp("Health Check Input",
+    Description = "Periodically GET an HTTP resource and publish response metrics to Seq.")]
+public class HealthCheckInput : SeqApp, IPublishJson, IDisposable
 {
-    [SeqApp("Health Check Input",
-        Description = "Periodically GET an HTTP resource and publish response metrics to Seq.")]
-    public class HealthCheckInput : SeqApp, IPublishJson, IDisposable
+    readonly List<HealthCheckTask> _healthCheckTasks = [];
+    HttpClient? _httpClient;
+
+    [SeqAppSetting(
+        DisplayName = "Target URLs",
+        HelpText = "The HTTP or HTTPS URL that the health check will periodically GET. Multiple URLs " +
+                   "can be checked; enter one per line.",
+        InputType = SettingInputType.LongText)]
+    public string TargetUrl { get; set; } = null!;
+
+    [SeqAppSetting(
+        DisplayName = "Follow Redirects",
+        IsOptional = true,
+        HelpText = "If selected, the HTTP request will follow redirects. By default, health checks that trigger redirects will fail.",
+        InputType = SettingInputType.Checkbox)]
+    public bool FollowRedirects { get; set; } = false;
+
+    [SeqAppSetting(InputType = SettingInputType.Password, IsOptional = true, DisplayName = "Authentication Header",
+        HelpText = "An optional `Name: Value` header, stored as sensitive data, for authentication purposes.")]
+    public string? AuthenticationHeader { get; set; }
+
+    [SeqAppSetting(InputType = SettingInputType.LongText, IsOptional = true, DisplayName = "Other Headers",
+        HelpText = "Additional headers to send with the request, one per line in `Name: Value` format.")]
+    public string? OtherHeaders { get; set; }
+
+    [SeqAppSetting(
+        DisplayName = "Bypass HTTP caching",
+        IsOptional = true,
+        HelpText = "If selected, the unique probe id will be appended to the target URL query string as " +
+                   "`" + HttpHealthCheck.ProbeIdParameterName + "`, in order to disable any " +
+                   "intermediary HTTP caching. The `Cache-Control: no-store` header will also be sent.")]
+    public bool BypassHttpCaching { get; set; }
+
+    [SeqAppSetting(
+        DisplayName = "Interval (seconds)",
+        IsOptional = true,
+        HelpText = "The time between checks; the default is 60.")]
+    public int IntervalSeconds { get; set; } = 60;
+
+    [SeqAppSetting(
+        DisplayName = "Data extraction expression",
+        IsOptional = true,
+        HelpText = "A Seq query language expression used to extract information from JSON responses. " +
+                   "The expression will be evaluated against the response to produce a `Data` property" +
+                   " on the resulting event. Use the special value `@Properties` to capture the whole " +
+                   "response. The response must be UTF-8 `application/json` for this to be applied.")]
+    public string? DataExtractionExpression { get; set; }
+
+    public void Start(TextWriter inputWriter)
     {
-        readonly List<HealthCheckTask> _healthCheckTasks = new List<HealthCheckTask>();
-        HttpClient? _httpClient;
-
-        [SeqAppSetting(
-            DisplayName = "Target URLs",
-            HelpText = "The HTTP or HTTPS URL that the health check will periodically GET. Multiple URLs " +
-                       "can be checked; enter one per line.",
-            InputType = SettingInputType.LongText)]
-        public string TargetUrl { get; set; } = null!;
-
-        [SeqAppSetting(InputType = SettingInputType.Password, IsOptional = true, DisplayName = "Authentication Header",
-            HelpText = "An optional `Name: Value` header, stored as sensitive data, for authentication purposes.")]
-        public string? AuthenticationHeader { get; set; }
-        
-        [SeqAppSetting(InputType = SettingInputType.LongText, IsOptional = true, DisplayName = "Other Headers",
-            HelpText = "Additional headers to send with the request, one per line in `Name: Value` format.")]
-        public string? OtherHeaders { get; set; }
-        
-        [SeqAppSetting(
-            DisplayName = "Bypass HTTP caching",
-            IsOptional = true,
-            HelpText = "If selected, the unique probe id will be appended to the target URL query string as " +
-                "`" + HttpHealthCheck.ProbeIdParameterName  + "`, in order to disable any " +
-                "intermediary HTTP caching. The `Cache-Control: no-store` header will also be sent.")]
-        public bool BypassHttpCaching { get; set; }
-
-        [SeqAppSetting(
-            DisplayName = "Interval (seconds)",
-            IsOptional = true,
-            HelpText = "The time between checks; the default is 60.")]
-        public int IntervalSeconds { get; set; } = 60;
-
-        [SeqAppSetting(
-            DisplayName = "Data extraction expression",
-            IsOptional = true,
-            HelpText = "A Seq query language expression used to extract information from JSON responses. " +
-                       "The expression will be evaluated against the response to produce a `Data` property" +
-                       " on the resulting event. Use the special value `@Properties` to capture the whole " +
-                       "response. The response must be UTF-8 `application/json` for this to be applied.")]
-        public string? DataExtractionExpression { get; set; }
-        
-        public void Start(TextWriter inputWriter)
-        {
-            _httpClient = HttpHealthCheckClient.Create();
-            var reporter = new HealthCheckReporter(inputWriter);
-
-            JsonDataExtractor? extractor = null;
-            if (!string.IsNullOrWhiteSpace(DataExtractionExpression))
-                extractor = new JsonDataExtractor(DataExtractionExpression);
-
-            var targetUrls = TargetUrl.Split(new[] {'\r', '\n'}, StringSplitOptions.RemoveEmptyEntries);
-            foreach (var targetUrl in targetUrls)
-            {
-                var healthCheck = new HttpHealthCheck(
-                    _httpClient,
-                    App.Title,
-                    targetUrl,
-                    HeaderSettingFormat.FromSettings(AuthenticationHeader, OtherHeaders),
-                    extractor,
-                    BypassHttpCaching);
-
-                _healthCheckTasks.Add(new HealthCheckTask(
-                    healthCheck,
-                    TimeSpan.FromSeconds(IntervalSeconds),
-                    reporter,
-                    Log));
-            }
-        }
+        _httpClient = HttpHealthCheckClient.Create();
+        var reporter = new HealthCheckReporter(inputWriter);
 
-        public void Stop()
-        {
-            foreach (var task in _healthCheckTasks)
-                task.Stop();
-        }
+        JsonDataExtractor? extractor = null;
+        if (!string.IsNullOrWhiteSpace(DataExtractionExpression))
+            extractor = new JsonDataExtractor(DataExtractionExpression);
 
-        public void Dispose()
+        var targetUrls = TargetUrl.Split(new[] {'\r', '\n'}, StringSplitOptions.RemoveEmptyEntries);
+        foreach (var targetUrl in targetUrls)
         {
-            foreach (var task in _healthCheckTasks)
-                task.Dispose();
+            var healthCheck = new HttpHealthCheck(
+                _httpClient,
+                App.Title,
+                targetUrl,
+                HeaderSettingFormat.FromSettings(AuthenticationHeader, OtherHeaders),
+                extractor,
+                BypassHttpCaching,
+                FollowRedirects);
 
-            _httpClient?.Dispose();
+            _healthCheckTasks.Add(new HealthCheckTask(
+                healthCheck,
+                TimeSpan.FromSeconds(IntervalSeconds),
+                reporter,
+                Log));
         }
     }
-}
+
+    public void Stop()
+    {
+        foreach (var task in _healthCheckTasks)
+            task.Stop();
+    }
+
+    public void Dispose()
+    {
+        foreach (var task in _healthCheckTasks)
+            task.Dispose();
+
+        _httpClient?.Dispose();
+    }
+}