Add docs on publishing messages in transactions with help of Forwarder component #261
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Probably not a docs problem, but when using example as stupid copy&paste on postgresql it produces error: Probably escaping problem as you can create table with dashes on postgres when properly escaped :) |
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| ## Publishing messages in transactions (and why we should care) | ||
| While working with an event-driven application, you may in some point need to store an application state and publish a message |
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It may be good to add tl;dr a problem statement in the first paragraph. Just to ensure that reader will instantly know what is the problem. If he will not find it in the first paragraph, it's a high chance that he will not read it further. Later we can go into the details and example 😉
It may be worth mentioning that we are avoiding two phrase commit + some diagram. (bonus point for diagram in .svg).
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I made the first paragraph focused on a problem and its solution - the Forwarder. :P svg diagram explaining how the component works added as well.
| mechanism which happens to be implemented by most of the databases in today's world. One of them is MySQL used in our | ||
| example. | ||
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| In order to commit both storing data and emitting an event in one transaction, we'd have to be able to publish our |
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IMO it would be good to put this and the next paragraph on the top: just to let know the reader what this component gives to him. If it will be here, it's a big chance that he will not read it 😉
| While working with an event-driven application, you may in some point need to store an application state and publish a message | ||
| telling the rest of the system about what just happened. As it may look trivial at a first glance, it could become | ||
| a bit tricky if we consider what can go wrong in case we won't pay enough attention to details. | ||
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it would be cool to link here to watermill.io component docs 😉
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Linked to the component source code.
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| This example presents a solution to this problem: saving events in transaction along with persisting application state. | ||
| It also compares two other approaches which lack transactional publishing therefore expose application to a risk | ||
| of inconsistency across the system. |
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Some diagram may be nice here 😉 miro works pretty well for diagrams, draw.io as well. It could be added in watermill.io as well 😉
Thanks for info. I've changed the topic name to not include dashes to make it simpler. :) |
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