Target netstandard2, Yaml support, object graph support (#328)

Author: danielgerlag

README.md

@@ -25,9 +25,9 @@ public class MyWorkflow : IWorkflow
 }
 ```
 
-## JSON Workflow Definitions
+## JSON / YAML Workflow Definitions
 
-Define your workflows in JSON
+Define your workflows in JSON or YAML
 
 ```json
 {
@@ -47,6 +47,17 @@ Define your workflows in JSON
 }
 ```
 
+```yaml
+Id: HelloWorld
+Version: 1
+Steps:
+- Id: Hello
+  StepType: MyApp.HelloWorld, MyApp
+  NextStepId: Bye
+- Id: Bye
+  StepType: MyApp.GoodbyeWorld, MyApp
+```
+
 ### Sample use cases
 
 * New user workflow

ReleaseNotes/2.0.0.md

@@ -0,0 +1,72 @@
+# Workflow Core 2.0.0
+
+### Upgrade notes
+Existing JSON definitions will be loaded as follows
+  ```c#
+  using WorkflowCore.Services.DefinitionStorage;
+  ...
+  DefinitionLoader.LoadDefinition(json, Deserializers.Json);
+  ```
+
+
+* Targets .NET Standard 2.0
+
+  The core library now targets .NET Standard 2.0, in order to leverage newer features.
+
+* Support for YAML definitions
+
+  Added support for YAML workflow definitions, which can be loaded as follows
+  ```c#
+  using WorkflowCore.Services.DefinitionStorage;
+  ...
+  DefinitionLoader.LoadDefinition(json, Deserializers.Yaml);
+  ```
+
+  Existing JSON definitions will be loaded as follows
+  ```c#
+  using WorkflowCore.Services.DefinitionStorage;
+  ...
+  DefinitionLoader.LoadDefinition(json, Deserializers.Json);
+  ```
+  
+* Object graphs and inline expressions on input properties
+
+  You can now pass object graphs to step inputs as opposed to just scalar values
+  ```
+  "inputs": 
+  {    
+    "Body": {
+        "Value1": 1,
+        "Value2": 2
+    },
+    "Headers": {
+        "Content-Type": "application/json"
+    }
+  },
+  ```
+  If you want to evaluate an expression for a given property of your object, simply prepend and `@` and pass an expression string
+  ```
+  "inputs": 
+  {    
+    "Body": {
+        "@Value1": "data.MyValue * 2",
+        "Value2": 5
+    },
+    "Headers": {
+        "Content-Type": "application/json"
+    }
+  },
+  ```
+
+* Support for enum values on input properties
+
+  If your step has an enum property, you can now just pass the string representation of the enum value and it will be automatically converted.
+
+* Environment variables available in input expressions
+
+  You can now access environment variables from within input expressions.
+  usage:
+  ```
+  environment["VARIABLE_NAME"]
+  ```
+

WorkflowCore.sln

@@ -40,8 +40,6 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.Persistence.Po
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.Persistence.Sqlite", "src\providers\WorkflowCore.Persistence.Sqlite\WorkflowCore.Persistence.Sqlite.csproj", "{86BC1E05-E9CE-4E53-B324-885A2FDBCE74}"
 EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.LockProviders.Redlock", "src\providers\WorkflowCore.LockProviders.Redlock\WorkflowCore.LockProviders.Redlock.csproj", "{05250D58-A59E-4212-8D55-E7BC0396E9F5}"
-EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.QueueProviders.RabbitMQ", "src\providers\WorkflowCore.QueueProviders.RabbitMQ\WorkflowCore.QueueProviders.RabbitMQ.csproj", "{AFAD87C7-B2EE-451E-BA7E-3F5A91358C48}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.Sample06", "src\samples\WorkflowCore.Sample06\WorkflowCore.Sample06.csproj", "{8FEAFD74-C304-4F75-BA38-4686BE55C891}"
@@ -100,6 +98,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "ReleaseNotes", "ReleaseNote
 		ReleaseNotes\1.9.0.md = ReleaseNotes\1.9.0.md
 		ReleaseNotes\1.9.2.md = ReleaseNotes\1.9.2.md
 		ReleaseNotes\1.9.3.md = ReleaseNotes\1.9.3.md
+		ReleaseNotes\2.0.0.md = ReleaseNotes\2.0.0.md
 	EndProjectSection
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.Sample14", "src\samples\WorkflowCore.Sample14\WorkflowCore.Sample14.csproj", "{6BC66637-B42A-4334-ADFB-DBEC9F29D293}"
@@ -114,8 +113,6 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.Sample15", "sr
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.Sample16", "src\samples\WorkflowCore.Sample16\WorkflowCore.Sample16.csproj", "{0C9617A9-C8B7-45F6-A54A-261A23AC881B}"
 EndProject
-Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ScratchPad", "test\ScratchPad\ScratchPad.csproj", "{6396453F-4D0E-4CD4-BC89-87E8970F2A80}"
-EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.Sample17", "src\samples\WorkflowCore.Sample17\WorkflowCore.Sample17.csproj", "{42F475BC-95F4-42E1-8CCD-7B9C27487E33}"
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WorkflowCore.QueueProviders.SqlServer", "src\providers\WorkflowCore.QueueProviders.SqlServer\WorkflowCore.QueueProviders.SqlServer.csproj", "{7EDD9353-F5C2-414C-AE51-4B0F1C5E105A}"
@@ -186,10 +183,6 @@ Global
 		{86BC1E05-E9CE-4E53-B324-885A2FDBCE74}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{86BC1E05-E9CE-4E53-B324-885A2FDBCE74}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{86BC1E05-E9CE-4E53-B324-885A2FDBCE74}.Release|Any CPU.Build.0 = Release|Any CPU
-		{05250D58-A59E-4212-8D55-E7BC0396E9F5}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{05250D58-A59E-4212-8D55-E7BC0396E9F5}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{05250D58-A59E-4212-8D55-E7BC0396E9F5}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{05250D58-A59E-4212-8D55-E7BC0396E9F5}.Release|Any CPU.Build.0 = Release|Any CPU
 		{AFAD87C7-B2EE-451E-BA7E-3F5A91358C48}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{AFAD87C7-B2EE-451E-BA7E-3F5A91358C48}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{AFAD87C7-B2EE-451E-BA7E-3F5A91358C48}.Release|Any CPU.ActiveCfg = Release|Any CPU
@@ -294,10 +287,6 @@ Global
 		{0C9617A9-C8B7-45F6-A54A-261A23AC881B}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{0C9617A9-C8B7-45F6-A54A-261A23AC881B}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{0C9617A9-C8B7-45F6-A54A-261A23AC881B}.Release|Any CPU.Build.0 = Release|Any CPU
-		{6396453F-4D0E-4CD4-BC89-87E8970F2A80}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{6396453F-4D0E-4CD4-BC89-87E8970F2A80}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{6396453F-4D0E-4CD4-BC89-87E8970F2A80}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{6396453F-4D0E-4CD4-BC89-87E8970F2A80}.Release|Any CPU.Build.0 = Release|Any CPU
 		{42F475BC-95F4-42E1-8CCD-7B9C27487E33}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{42F475BC-95F4-42E1-8CCD-7B9C27487E33}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{42F475BC-95F4-42E1-8CCD-7B9C27487E33}.Release|Any CPU.ActiveCfg = Release|Any CPU
@@ -357,7 +346,6 @@ Global
 		{1DE96D4F-F2CA-4740-8764-BADD1000040A} = {2EEE6ABD-EE9B-473F-AF2D-6DABB85D7BA2}
 		{9274B938-3996-4FBA-AE2F-0C82009B1116} = {2EEE6ABD-EE9B-473F-AF2D-6DABB85D7BA2}
 		{86BC1E05-E9CE-4E53-B324-885A2FDBCE74} = {2EEE6ABD-EE9B-473F-AF2D-6DABB85D7BA2}
-		{05250D58-A59E-4212-8D55-E7BC0396E9F5} = {2EEE6ABD-EE9B-473F-AF2D-6DABB85D7BA2}
 		{AFAD87C7-B2EE-451E-BA7E-3F5A91358C48} = {2EEE6ABD-EE9B-473F-AF2D-6DABB85D7BA2}
 		{8FEAFD74-C304-4F75-BA38-4686BE55C891} = {5080DB09-CBE8-4C45-9957-C3BB7651755E}
 		{37B598A8-B054-4ABA-884D-96AEF2511600} = {E6CEAD8D-F565-471E-A0DC-676F54EAEDEB}
@@ -384,7 +372,6 @@ Global
 		{EC497168-5347-4E70-9D9E-9C2F826C1CDF} = {E6CEAD8D-F565-471E-A0DC-676F54EAEDEB}
 		{9B7811AC-68D6-4D19-B1E9-65423393ED83} = {5080DB09-CBE8-4C45-9957-C3BB7651755E}
 		{0C9617A9-C8B7-45F6-A54A-261A23AC881B} = {5080DB09-CBE8-4C45-9957-C3BB7651755E}
-		{6396453F-4D0E-4CD4-BC89-87E8970F2A80} = {E6CEAD8D-F565-471E-A0DC-676F54EAEDEB}
 		{42F475BC-95F4-42E1-8CCD-7B9C27487E33} = {5080DB09-CBE8-4C45-9957-C3BB7651755E}
 		{7EDD9353-F5C2-414C-AE51-4B0F1C5E105A} = {2EEE6ABD-EE9B-473F-AF2D-6DABB85D7BA2}
 		{5E82A137-0954-46A1-8C46-13C00F0E4842} = {2EEE6ABD-EE9B-473F-AF2D-6DABB85D7BA2}

src/WorkflowCore/Interface/IDefinitionLoader.cs

@@ -1,9 +1,11 @@
-using WorkflowCore.Models;
+using System;
+using WorkflowCore.Models;
+using WorkflowCore.Models.DefinitionStorage.v1;
 
 namespace WorkflowCore.Interface
 {
     public interface IDefinitionLoader
     {
-        WorkflowDefinition LoadDefinition(string json);
+        WorkflowDefinition LoadDefinition(string source, Func<string, DefinitionSourceV1> deserializer);
     }
 }

src/WorkflowCore/Models/DefinitionStorage/v1/StepSourceV1.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Dynamic;
 using System.Text;
 
 namespace WorkflowCore.Models.DefinitionStorage.v1
@@ -26,7 +27,7 @@ public class StepSourceV1
 
         public string NextStepId { get; set; }
 
-        public Dictionary<string, string> Inputs { get; set; } = new Dictionary<string, string>();
+        public ExpandoObject Inputs { get; set; } = new ExpandoObject();
 
         public Dictionary<string, string> Outputs { get; set; } = new Dictionary<string, string>();
 

src/WorkflowCore/Services/DefinitionStorage/DefinitionLoader.cs

@@ -1,11 +1,13 @@
 using Newtonsoft.Json;
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
 using System.Linq.Dynamic.Core;
 using System.Linq.Expressions;
 using System.Reflection;
 using System.Text;
+using Newtonsoft.Json.Linq;
 using WorkflowCore.Interface;
 using WorkflowCore.Models;
 using WorkflowCore.Primitives;
@@ -24,10 +26,10 @@ public DefinitionLoader(IWorkflowRegistry registry)
             _registry = registry;
         }
 
-        public WorkflowDefinition LoadDefinition(string json)
+        public WorkflowDefinition LoadDefinition(string source, Func<string, DefinitionSourceV1> deserializer)
         {
-            var source = JsonConvert.DeserializeObject<DefinitionSourceV1>(json);
-            var def = Convert(source);
+            var sourceObj = deserializer(source);
+            var def = Convert(sourceObj);
             _registry.RegisterWorkflow(def);
             return def;
         }
@@ -171,13 +173,24 @@ private void AttachInputs(StepSourceV1 source, Type dataType, Type stepType, Wor
             {
                 var dataParameter = Expression.Parameter(dataType, "data");
                 var contextParameter = Expression.Parameter(typeof(IStepExecutionContext), "context");
-                var sourceExpr = DynamicExpressionParser.ParseLambda(new [] { dataParameter, contextParameter }, typeof(object), input.Value);
+                var environmentVarsParameter = Expression.Parameter(typeof(IDictionary), "environment");
+                var stepProperty = stepType.GetProperty(input.Key);
 
-                var stepParameter = Expression.Parameter(stepType, "step");
-                var targetProperty = Expression.Property(stepParameter, input.Key);
-                var targetExpr = Expression.Lambda(targetProperty, stepParameter);
+                if (input.Value is string)
+                {
+                    var acn = BuildScalarInputAction(input, dataParameter, contextParameter, environmentVarsParameter, stepProperty);
+                    step.Inputs.Add(new ActionParameter<IStepBody, object>(acn));
+                    continue;
+                }
 
-                step.Inputs.Add(new MemberMapParameter(sourceExpr, targetExpr));
+                if ((input.Value is IDictionary<string, object>) || (input.Value is IDictionary<object, object>))
+                {
+                    var acn = BuildObjectInputAction(input, dataParameter, contextParameter, environmentVarsParameter, stepProperty);
+                    step.Inputs.Add(new ActionParameter<IStepBody, object>(acn));
+                    continue;
+                }
+
+                throw new ArgumentException($"Unknown type for input {input.Key} on {source.Id}");
             }
         }
 
@@ -221,5 +234,52 @@ private Type FindType(string name)
             return Type.GetType(name, true, true);
         }
 
+        private static Action<IStepBody, object, IStepExecutionContext> BuildScalarInputAction(KeyValuePair<string, object> input, ParameterExpression dataParameter, ParameterExpression contextParameter, ParameterExpression environmentVarsParameter, PropertyInfo stepProperty)
+        {
+            var expr = System.Convert.ToString(input.Value);
+            var sourceExpr = DynamicExpressionParser.ParseLambda(new[] { dataParameter, contextParameter, environmentVarsParameter }, typeof(object), expr);
+
+            void acn(IStepBody pStep, object pData, IStepExecutionContext pContext)
+            {
+                object resolvedValue = sourceExpr.Compile().DynamicInvoke(pData, pContext, Environment.GetEnvironmentVariables());
+                if (stepProperty.PropertyType.IsEnum)
+                    stepProperty.SetValue(pStep, Enum.Parse(stepProperty.PropertyType, (string)resolvedValue, true));
+                else
+                    stepProperty.SetValue(pStep, System.Convert.ChangeType(resolvedValue, stepProperty.PropertyType));
+            }
+            return acn;
+        }
+
+        private static Action<IStepBody, object, IStepExecutionContext> BuildObjectInputAction(KeyValuePair<string, object> input, ParameterExpression dataParameter, ParameterExpression contextParameter, ParameterExpression environmentVarsParameter, PropertyInfo stepProperty)
+        {
+            void acn(IStepBody pStep, object pData, IStepExecutionContext pContext)
+            {
+                var stack = new Stack<JObject>();
+                var destObj = JObject.FromObject(input.Value);
+                stack.Push(destObj);
+
+                while (stack.Count > 0)
+                {
+                    var subobj = stack.Pop();
+                    foreach (var prop in subobj.Properties().ToList())
+                    {
+                        if (prop.Name.StartsWith("@"))
+                        {
+                            var sourceExpr = DynamicExpressionParser.ParseLambda(new[] { dataParameter, contextParameter, environmentVarsParameter }, typeof(object), prop.Value.ToString());
+                            object resolvedValue = sourceExpr.Compile().DynamicInvoke(pData, pContext, Environment.GetEnvironmentVariables());
+                            subobj.Remove(prop.Name);
+                            subobj.Add(prop.Name.TrimStart('@'), JToken.FromObject(resolvedValue));
+                        }
+                    }
+
+                    foreach (var child in subobj.Children<JObject>())
+                        stack.Push(child);
+                }
+
+                stepProperty.SetValue(pStep, destObj);
+            }
+            return acn;
+        }
+
     }
 }

src/WorkflowCore/Services/DefinitionStorage/Deserializers.cs

@@ -0,0 +1,16 @@
+using System;
+using Newtonsoft.Json;
+using SharpYaml.Serialization;
+using WorkflowCore.Models.DefinitionStorage.v1;
+
+namespace WorkflowCore.Services.DefinitionStorage
+{
+    public static class Deserializers
+    {
+        private static Serializer yamlSerializer = new Serializer();
+
+        public static Func<string, DefinitionSourceV1> Json = (source) => JsonConvert.DeserializeObject<DefinitionSourceV1>(source);
+
+        public static Func<string, DefinitionSourceV1> Yaml = (source) => yamlSerializer.DeserializeInto(source, new DefinitionSourceV1());
+    }
+}

src/WorkflowCore/WorkflowCore.csproj

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <AssemblyTitle>Workflow Core</AssemblyTitle>
     <Authors>Daniel Gerlag</Authors>
-    <TargetFramework>netstandard1.3</TargetFramework>
+    <TargetFramework>netstandard2.0</TargetFramework>
     <AssemblyName>WorkflowCore</AssemblyName>
     <PackageId>WorkflowCore</PackageId>
     <PackageTags>workflow;.NET;Core;state machine</PackageTags>
@@ -15,33 +15,26 @@
     <GenerateAssemblyCompanyAttribute>false</GenerateAssemblyCompanyAttribute>
     <GenerateAssemblyProductAttribute>false</GenerateAssemblyProductAttribute>
     <Description>Workflow Core is a light weight workflow engine targeting .NET Standard.</Description>
-    <Version>1.9.4</Version>
-    <AssemblyVersion>1.9.4.0</AssemblyVersion>
-    <FileVersion>1.9.4.0</FileVersion>
+    <Version>2.0.0</Version>
+    <AssemblyVersion>2.0.0.0</AssemblyVersion>
+    <FileVersion>2.0.0.0</FileVersion>
     <PackageReleaseNotes></PackageReleaseNotes>
     <PackageIconUrl>https://github.com/danielgerlag/workflow-core/raw/master/src/logo.png</PackageIconUrl>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="1.1.1" />
-    <PackageReference Include="Microsoft.Extensions.Logging" Version="1.1.1" />
-    <PackageReference Include="Microsoft.Extensions.ObjectPool" Version="1.1.1" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="2.1.0" />
+    <PackageReference Include="Microsoft.Extensions.Logging" Version="2.1.0" />
+    <PackageReference Include="Microsoft.Extensions.ObjectPool" Version="2.2.0" />
     <PackageReference Include="Newtonsoft.Json" Version="12.0.1" />
+    <PackageReference Include="SharpYaml" Version="1.6.5" />
     <PackageReference Include="System.Linq.Dynamic.Core" Version="1.0.7.12" />
     <PackageReference Include="System.Threading.Tasks.Parallel" Version="4.3.0" />
     <PackageReference Include="System.Threading.ThreadPool" Version="4.3.0" />
-  </ItemGroup>
-
-  <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard1.3' ">
     <PackageReference Include="System.Reflection" Version="4.3.0" />
     <PackageReference Include="System.Reflection.TypeExtensions" Version="4.3.0" />
     <PackageReference Include="System.Threading.Thread" Version="4.3.0" />
     <PackageReference Include="System.Linq.Queryable" Version="4.3.0" />
   </ItemGroup>
 
-  <ItemGroup Condition=" '$(TargetFramework)' == 'net452' ">
-    <Reference Include="System" />
-    <Reference Include="Microsoft.CSharp" />
-  </ItemGroup>
-
 </Project>