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416:\n/***/ (function(module, exports) {\n\n\tmodule.exports = {\"data\":{\"allPostTitles\":{\"edges\":[{\"node\":{\"frontmatter\":{\"title\":\"Getting Started\",\"lesson\":1,\"category\":\"akkatecture\",\"chapter\":1,\"type\":\"docs\"},\"fields\":{\"slug\":\"/getting-started\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Primitives\",\"lesson\":1,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/primitives\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Walkthrough Introduction\",\"lesson\":1,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/walkthrough-introduction\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Sagas\",\"lesson\":1,\"category\":\"akkatecture\",\"chapter\":4,\"type\":\"docs\"},\"fields\":{\"slug\":\"/sagas\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Tips and 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Test\",\"lesson\":6,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-aggregate-test\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Testing Aggregates\",\"lesson\":6,\"category\":\"akkatecture\",\"chapter\":4,\"type\":\"docs\"},\"fields\":{\"slug\":\"/testing-aggregates\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Scheduled Jobs\",\"lesson\":7,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/scheduled-jobs\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Aggregate Saga\",\"lesson\":7,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-aggregate-saga\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Akka\",\"lesson\":8,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/akka\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Subscribers\",\"lesson\":8,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-subscribers\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Configuration\",\"lesson\":9,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/configuration\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Projections\",\"lesson\":9,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-projections\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Walkthrough Ending\",\"lesson\":10,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/walkthrough-ending\"}}}]},\"postBySlug\":{\"html\":\"<p>Also sometimes known as event upcasting. At some point you might find the need to replace a event with zero or more events. Some use cases might be:</p>\\n<ul>\\n<li>A previous application version introduced a domain error in the form of a wrong event being emitted from the aggregate.</li>\\n<li>The domain has changed, either from a change in requirements or simply from a better understanding of the domain.</li>\\n</ul>\\n<p>In the above cases, Akkatecture suggests that you implement an <code class=\\\"language-text\\\">AggregateEventUpcaster&lt;,&gt;</code> and then you can add your own upcast implementation by implementing <code class=\\\"language-text\\\">IUpcast&lt;,&gt;</code> on the upcaster. Lets do this with an example.</p>\\n<p>Imagine we have an OrderAggregate that emits <code class=\\\"language-text\\\">ProductAddedEvent</code>s, due to new domain improvements or required it has been deemed necessary to have a new version of that event called <code class=\\\"language-text\\\">ProductAddedEventV2</code>. We make changes to the aggregate to emit the new version of the event, but we have a problem in that the old event is persisted in the event journal. To remedy this we will implement a suitable <code class=\\\"language-text\\\">AggregateEventUpcaster&lt;,&gt;</code>.</p>\\n<div class=\\\"gatsby-highlight\\\">\\n      <pre class=\\\"language-csharp\\\"><code class=\\\"language-csharp\\\"><span class=\\\"token keyword\\\">public</span> <span class=\\\"token keyword\\\">class</span> <span class=\\\"token class-name\\\">OrderAggregateEventUpcaster</span> <span class=\\\"token punctuation\\\">:</span> <span class=\\\"token class-name\\\">AggregateEventUpcaster</span><span class=\\\"token operator\\\">&lt;</span>OrderAggregate<span class=\\\"token punctuation\\\">,</span> OrderId<span class=\\\"token operator\\\">></span><span class=\\\"token punctuation\\\">,</span>\\n        IUpcast<span class=\\\"token operator\\\">&lt;</span>ProductAddedEvent<span class=\\\"token punctuation\\\">,</span> ProductAddedEventV2<span class=\\\"token operator\\\">></span>\\n    <span class=\\\"token punctuation\\\">{</span>\\n        <span class=\\\"token keyword\\\">public</span> <span class=\\\"token class-name\\\">ProductAddedEventV2</span> <span class=\\\"token function\\\">Upcast</span><span class=\\\"token punctuation\\\">(</span><span class=\\\"token class-name\\\">ProductAddedEvent</span> aggregateEvent<span class=\\\"token punctuation\\\">)</span>\\n        <span class=\\\"token punctuation\\\">{</span>\\n            <span class=\\\"token keyword\\\">return</span> <span class=\\\"token keyword\\\">new</span> <span class=\\\"token class-name\\\">ProductAddedEventV2</span><span class=\\\"token punctuation\\\">(</span>\\n                aggregateEvent<span class=\\\"token punctuation\\\">.</span>AggregateId<span class=\\\"token punctuation\\\">,</span>\\n                <span class=\\\"token comment\\\">/* other things to enrich the event */</span>\\n                <span class=\\\"token keyword\\\">string</span><span class=\\\"token punctuation\\\">.</span>Empty<span class=\\\"token punctuation\\\">)</span><span class=\\\"token punctuation\\\">;</span>\\n        <span class=\\\"token punctuation\\\">}</span>\\n    <span class=\\\"token punctuation\\\">}</span></code></pre>\\n      </div>\\n<p>and then our read journal hocon configuration requires the following to be added to it</p>\\n<div class=\\\"gatsby-highlight\\\">\\n      <pre class=\\\"language-json\\\"><code class=\\\"language-json\\\">akka.persistence <span class=\\\"token punctuation\\\">{</span>\\n    journal <span class=\\\"token punctuation\\\">{</span>\\n        plugin = <span class=\\\"token string\\\">\\\"\\\"</span>akka.persistence.journal.some-plugin<span class=\\\"token string\\\">\\\"\\\"</span>\\n        some-plugin <span class=\\\"token punctuation\\\">{</span>\\n\\t\\t\\tevent-adapters <span class=\\\"token punctuation\\\">{</span>\\n                ##fully qualified class name and assembly of the upcaster\\n\\t\\t\\t\\taggregate-event-upcaster  = <span class=\\\"token string\\\">\\\"\\\"</span>YourDomain.OrderAggregateEventUpcaster<span class=\\\"token punctuation\\\">,</span> YourDomain<span class=\\\"token string\\\">\\\"\\\"</span>\\n\\t\\t\\t<span class=\\\"token punctuation\\\">}</span>\\n\\t\\t\\tevent-adapter-bindings = <span class=\\\"token punctuation\\\">{</span>\\n\\t\\t\\t\\t<span class=\\\"token string\\\">\\\"\\\"</span>Akkatecture.Aggregates.ICommittedEvent<span class=\\\"token punctuation\\\">,</span> Akkatecture<span class=\\\"token string\\\">\\\"\\\"</span> = aggregate-event-upcaster\\n\\t\\t\\t<span class=\\\"token punctuation\\\">}</span>\\n        <span class=\\\"token punctuation\\\">}</span>\\n    <span class=\\\"token punctuation\\\">}</span>\\n<span class=\\\"token punctuation\\\">}</span></code></pre>\\n      </div>\\n<p>Now in our order aggrege state, we only need to implement the apply method of the new aggregate event</p>\\n<div class=\\\"gatsby-highlight\\\">\\n      <pre class=\\\"language-csharp\\\"><code class=\\\"language-csharp\\\"><span class=\\\"token keyword\\\">public</span> <span class=\\\"token keyword\\\">class</span> <span class=\\\"token class-name\\\">OrderState</span> <span class=\\\"token punctuation\\\">:</span> <span class=\\\"token class-name\\\">AggregateState</span><span class=\\\"token operator\\\">&lt;</span>OrderState<span class=\\\"token punctuation\\\">,</span> OrderId<span class=\\\"token operator\\\">></span><span class=\\\"token punctuation\\\">,</span>\\n    IApply<span class=\\\"token operator\\\">&lt;</span>ProductAddedEventV2<span class=\\\"token operator\\\">></span><span class=\\\"token punctuation\\\">,</span>\\n    IApply<span class=\\\"token operator\\\">&lt;</span>ProductRemovedEvent<span class=\\\"token operator\\\">></span><span class=\\\"token punctuation\\\">,</span>\\n<span class=\\\"token punctuation\\\">{</span>\\n    <span class=\\\"token keyword\\\">public</span> <span class=\\\"token class-name\\\">Products</span> Products <span class=\\\"token punctuation\\\">{</span> <span class=\\\"token keyword\\\">get</span><span class=\\\"token punctuation\\\">;</span> <span class=\\\"token keyword\\\">private</span> <span class=\\\"token keyword\\\">set</span><span class=\\\"token punctuation\\\">;</span> <span class=\\\"token punctuation\\\">}</span>\\n\\n    <span class=\\\"token keyword\\\">public</span> <span class=\\\"token keyword\\\">void</span> <span class=\\\"token function\\\">Apply</span><span class=\\\"token punctuation\\\">(</span><span class=\\\"token class-name\\\">ProductRemovedEvent</span> aggregateEvent<span class=\\\"token punctuation\\\">)</span>\\n    <span class=\\\"token punctuation\\\">{</span>\\n        Products<span class=\\\"token punctuation\\\">.</span><span class=\\\"token function\\\">Remove</span><span class=\\\"token punctuation\\\">(</span>aggregateEvent<span class=\\\"token punctuation\\\">.</span>Product<span class=\\\"token punctuation\\\">)</span><span class=\\\"token punctuation\\\">;</span>\\n    <span class=\\\"token punctuation\\\">}</span>\\n\\n    <span class=\\\"token keyword\\\">public</span> <span class=\\\"token keyword\\\">void</span> <span class=\\\"token function\\\">Apply</span><span class=\\\"token punctuation\\\">(</span><span class=\\\"token class-name\\\">ProductAddedEventV2</span> aggregateEvent<span class=\\\"token punctuation\\\">)</span>\\n    <span class=\\\"token punctuation\\\">{</span>\\n        Products<span class=\\\"token punctuation\\\">.</span><span class=\\\"token function\\\">Add</span><span class=\\\"token punctuation\\\">(</span>aggregateEvent<span class=\\\"token punctuation\\\">.</span>Product<span class=\\\"token punctuation\\\">)</span><span class=\\\"token punctuation\\\">;</span>\\n    <span class=\\\"token punctuation\\\">}</span>\\n<span class=\\\"token punctuation\\\">}</span></code></pre>\\n      </div>\\n<blockquote>\\n<p>The event upcaster works as a normal <code class=\\\"language-text\\\">IReadEventAdapter</code> from <a href=\\\"https://getakka.net/articles/persistence/event-adapters.html\\\">akka.net</a>.</p>\\n</blockquote>\",\"timeToRead\":2,\"excerpt\":\"Also sometimes known as event upcasting. At some point you might find the need to replace a event with zero or more events. Some use cases…\",\"frontmatter\":{\"title\":\"Event Upgrading\",\"cover\":\"https://unsplash.it/400/300/?random?BoldMage\",\"date\":\"01/07/2018\",\"category\":\"akkatecture\",\"tags\":[\"advanced-concepts\",\"akkatecture\",\"csharp\",\"dotnet\"]},\"fields\":{\"slug\":\"/event-upgrading\"}}},\"pathContext\":{\"slug\":\"/event-upgrading\",\"category\":\"akkatecture\"}}\n\n/***/ })\n\n});\n\n\n// WEBPACK FOOTER //\n// path---docs-event-upgrading-7bfbf10e95737176089f.js","module.exports = {\"data\":{\"allPostTitles\":{\"edges\":[{\"node\":{\"frontmatter\":{\"title\":\"Getting Started\",\"lesson\":1,\"category\":\"akkatecture\",\"chapter\":1,\"type\":\"docs\"},\"fields\":{\"slug\":\"/getting-started\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Primitives\",\"lesson\":1,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/primitives\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Walkthrough 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Commands\",\"lesson\":3,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-commands\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Clustering\",\"lesson\":3,\"category\":\"akkatecture\",\"chapter\":4,\"type\":\"docs\"},\"fields\":{\"slug\":\"/clustering\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Videos\",\"lesson\":3,\"category\":\"akkatecture\",\"chapter\":5,\"type\":\"docs\"},\"fields\":{\"slug\":\"/videos\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Commands\",\"lesson\":4,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/commands\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Events\",\"lesson\":4,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-events\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Production Readiness\",\"lesson\":4,\"category\":\"akkatecture\",\"chapter\":4,\"type\":\"docs\"},\"fields\":{\"slug\":\"/production-readiness\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Specifications\",\"lesson\":5,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/specifications\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Specifications\",\"lesson\":5,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-specifications\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Event Upgrading\",\"lesson\":5,\"category\":\"akkatecture\",\"chapter\":4,\"type\":\"docs\"},\"fields\":{\"slug\":\"/event-upgrading\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Subscribers\",\"lesson\":6,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/subscribers\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Aggregate Test\",\"lesson\":6,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-aggregate-test\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Testing Aggregates\",\"lesson\":6,\"category\":\"akkatecture\",\"chapter\":4,\"type\":\"docs\"},\"fields\":{\"slug\":\"/testing-aggregates\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Scheduled Jobs\",\"lesson\":7,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/scheduled-jobs\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Aggregate Saga\",\"lesson\":7,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-aggregate-saga\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Akka\",\"lesson\":8,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/akka\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Subscribers\",\"lesson\":8,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-subscribers\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Configuration\",\"lesson\":9,\"category\":\"akkatecture\",\"chapter\":2,\"type\":\"docs\"},\"fields\":{\"slug\":\"/configuration\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Your First Projections\",\"lesson\":9,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/your-first-projections\"}}},{\"node\":{\"frontmatter\":{\"title\":\"Walkthrough Ending\",\"lesson\":10,\"category\":\"akkatecture\",\"chapter\":3,\"type\":\"docs\"},\"fields\":{\"slug\":\"/walkthrough-ending\"}}}]},\"postBySlug\":{\"html\":\"<p>Also sometimes known as event upcasting. At some point you might find the need to replace a event with zero or more events. Some use cases might be:</p>\\n<ul>\\n<li>A previous application version introduced a domain error in the form of a wrong event being emitted from the aggregate.</li>\\n<li>The domain has changed, either from a change in requirements or simply from a better understanding of the domain.</li>\\n</ul>\\n<p>In the above cases, Akkatecture suggests that you implement an <code class=\\\"language-text\\\">AggregateEventUpcaster&lt;,&gt;</code> and then you can add your own upcast implementation by implementing <code class=\\\"language-text\\\">IUpcast&lt;,&gt;</code> on the upcaster. Lets do this with an example.</p>\\n<p>Imagine we have an OrderAggregate that emits <code class=\\\"language-text\\\">ProductAddedEvent</code>s, due to new domain improvements or required it has been deemed necessary to have a new version of that event called <code class=\\\"language-text\\\">ProductAddedEventV2</code>. We make changes to the aggregate to emit the new version of the event, but we have a problem in that the old event is persisted in the event journal. To remedy this we will implement a suitable <code class=\\\"language-text\\\">AggregateEventUpcaster&lt;,&gt;</code>.</p>\\n<div class=\\\"gatsby-highlight\\\">\\n      <pre class=\\\"language-csharp\\\"><code class=\\\"language-csharp\\\"><span class=\\\"token keyword\\\">public</span> <span class=\\\"token keyword\\\">class</span> <span class=\\\"token class-name\\\">OrderAggregateEventUpcaster</span> <span class=\\\"token punctuation\\\">:</span> <span class=\\\"token class-name\\\">AggregateEventUpcaster</span><span class=\\\"token operator\\\">&lt;</span>OrderAggregate<span class=\\\"token punctuation\\\">,</span> OrderId<span class=\\\"token operator\\\">></span><span class=\\\"token punctuation\\\">,</span>\\n        IUpcast<span class=\\\"token operator\\\">&lt;</span>ProductAddedEvent<span class=\\\"token punctuation\\\">,</span> ProductAddedEventV2<span class=\\\"token operator\\\">></span>\\n    <span class=\\\"token punctuation\\\">{</span>\\n        <span class=\\\"token keyword\\\">public</span> <span class=\\\"token class-name\\\">ProductAddedEventV2</span> <span class=\\\"token function\\\">Upcast</span><span class=\\\"token punctuation\\\">(</span><span class=\\\"token class-name\\\">ProductAddedEvent</span> aggregateEvent<span class=\\\"token punctuation\\\">)</span>\\n        <span class=\\\"token punctuation\\\">{</span>\\n            <span class=\\\"token keyword\\\">return</span> <span class=\\\"token keyword\\\">new</span> <span class=\\\"token class-name\\\">ProductAddedEventV2</span><span class=\\\"token punctuation\\\">(</span>\\n                aggregateEvent<span class=\\\"token punctuation\\\">.</span>AggregateId<span class=\\\"token punctuation\\\">,</span>\\n                <span class=\\\"token comment\\\">/* other things to enrich the event */</span>\\n                <span class=\\\"token keyword\\\">string</span><span class=\\\"token punctuation\\\">.</span>Empty<span class=\\\"token punctuation\\\">)</span><span class=\\\"token punctuation\\\">;</span>\\n        <span class=\\\"token punctuation\\\">}</span>\\n    <span class=\\\"token punctuation\\\">}</span></code></pre>\\n      </div>\\n<p>and then our read journal hocon configuration requires the following to be added to it</p>\\n<div class=\\\"gatsby-highlight\\\">\\n      <pre class=\\\"language-json\\\"><code class=\\\"language-json\\\">akka.persistence <span class=\\\"token punctuation\\\">{</span>\\n    journal <span class=\\\"token punctuation\\\">{</span>\\n        plugin = <span class=\\\"token string\\\">\\\"\\\"</span>akka.persistence.journal.some-plugin<span class=\\\"token string\\\">\\\"\\\"</span>\\n        some-plugin <span class=\\\"token punctuation\\\">{</span>\\n\\t\\t\\tevent-adapters <span class=\\\"token punctuation\\\">{</span>\\n                ##fully qualified class name and assembly of the upcaster\\n\\t\\t\\t\\taggregate-event-upcaster  = <span class=\\\"token string\\\">\\\"\\\"</span>YourDomain.OrderAggregateEventUpcaster<span class=\\\"token punctuation\\\">,</span> YourDomain<span class=\\\"token string\\\">\\\"\\\"</span>\\n\\t\\t\\t<span class=\\\"token punctuation\\\">}</span>\\n\\t\\t\\tevent-adapter-bindings = <span class=\\\"token punctuation\\\">{</span>\\n\\t\\t\\t\\t<span class=\\\"token string\\\">\\\"\\\"</span>Akkatecture.Aggregates.ICommittedEvent<span class=\\\"token punctuation\\\">,</span> Akkatecture<span class=\\\"token string\\\">\\\"\\\"</span> = aggregate-event-upcaster\\n\\t\\t\\t<span class=\\\"token punctuation\\\">}</span>\\n        <span class=\\\"token punctuation\\\">}</span>\\n    <span class=\\\"token punctuation\\\">}</span>\\n<span class=\\\"token punctuation\\\">}</span></code></pre>\\n      </div>\\n<p>Now in our order aggrege state, we only need to implement the apply method of the new aggregate event</p>\\n<div class=\\\"gatsby-highlight\\\">\\n      <pre class=\\\"language-csharp\\\"><code class=\\\"language-csharp\\\"><span class=\\\"token keyword\\\">public</span> <span class=\\\"token keyword\\\">class</span> <span class=\\\"token class-name\\\">OrderState</span> <span class=\\\"token punctuation\\\">:</span> <span class=\\\"token class-name\\\">AggregateState</span><span class=\\\"token operator\\\">&lt;</span>OrderState<span class=\\\"token punctuation\\\">,</span> OrderId<span class=\\\"token operator\\\">></span><span class=\\\"token punctuation\\\">,</span>\\n    IApply<span class=\\\"token operator\\\">&lt;</span>ProductAddedEventV2<span class=\\\"token operator\\\">></span><span class=\\\"token punctuation\\\">,</span>\\n    IApply<span class=\\\"token operator\\\">&lt;</span>ProductRemovedEvent<span class=\\\"token operator\\\">></span><span class=\\\"token punctuation\\\">,</span>\\n<span class=\\\"token punctuation\\\">{</span>\\n    <span class=\\\"token keyword\\\">public</span> <span class=\\\"token class-name\\\">Products</span> Products <span class=\\\"token punctuation\\\">{</span> <span class=\\\"token keyword\\\">get</span><span class=\\\"token punctuation\\\">;</span> <span class=\\\"token keyword\\\">private</span> <span class=\\\"token keyword\\\">set</span><span class=\\\"token punctuation\\\">;</span> <span class=\\\"token punctuation\\\">}</span>\\n\\n    <span class=\\\"token keyword\\\">public</span> <span class=\\\"token keyword\\\">void</span> <span class=\\\"token function\\\">Apply</span><span class=\\\"token punctuation\\\">(</span><span class=\\\"token class-name\\\">ProductRemovedEvent</span> aggregateEvent<span class=\\\"token punctuation\\\">)</span>\\n    <span class=\\\"token punctuation\\\">{</span>\\n        Products<span class=\\\"token punctuation\\\">.</span><span class=\\\"token function\\\">Remove</span><span class=\\\"token punctuation\\\">(</span>aggregateEvent<span class=\\\"token punctuation\\\">.</span>Product<span class=\\\"token punctuation\\\">)</span><span class=\\\"token punctuation\\\">;</span>\\n    <span class=\\\"token punctuation\\\">}</span>\\n\\n    <span class=\\\"token keyword\\\">public</span> <span class=\\\"token keyword\\\">void</span> <span class=\\\"token function\\\">Apply</span><span class=\\\"token punctuation\\\">(</span><span class=\\\"token class-name\\\">ProductAddedEventV2</span> aggregateEvent<span class=\\\"token punctuation\\\">)</span>\\n    <span class=\\\"token punctuation\\\">{</span>\\n        Products<span class=\\\"token punctuation\\\">.</span><span class=\\\"token function\\\">Add</span><span class=\\\"token punctuation\\\">(</span>aggregateEvent<span class=\\\"token punctuation\\\">.</span>Product<span class=\\\"token punctuation\\\">)</span><span class=\\\"token punctuation\\\">;</span>\\n    <span class=\\\"token punctuation\\\">}</span>\\n<span class=\\\"token punctuation\\\">}</span></code></pre>\\n      </div>\\n<blockquote>\\n<p>The event upcaster works as a normal <code class=\\\"language-text\\\">IReadEventAdapter</code> from <a href=\\\"https://getakka.net/articles/persistence/event-adapters.html\\\">akka.net</a>.</p>\\n</blockquote>\",\"timeToRead\":2,\"excerpt\":\"Also sometimes known as event upcasting. At some point you might find the need to replace a event with zero or more events. Some use cases…\",\"frontmatter\":{\"title\":\"Event Upgrading\",\"cover\":\"https://unsplash.it/400/300/?random?BoldMage\",\"date\":\"01/07/2018\",\"category\":\"akkatecture\",\"tags\":[\"advanced-concepts\",\"akkatecture\",\"csharp\",\"dotnet\"]},\"fields\":{\"slug\":\"/event-upgrading\"}}},\"pathContext\":{\"slug\":\"/event-upgrading\",\"category\":\"akkatecture\"}}\n\n\n//////////////////\n// WEBPACK FOOTER\n// ./~/json-loader!./.cache/json/docs-event-upgrading.json\n// module id = 416\n// module chunks = 79135866311530"],"sourceRoot":""}