fb67d90b64
- Split Module and Module Links to their own chapters - Add new docs on db operations and transactions in modules, multiple services, links with custom columns, etc... - Added a list of registered dependencies in a module container
41 lines
1.1 KiB
Plaintext
41 lines
1.1 KiB
Plaintext
export const metadata = {
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title: `${pageNumber} Service Constraints`,
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}
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# {metadata.title}
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This chapter lists constraints to keep in mind when creating a service.
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## Use Async Methods
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Medusa wraps service method executions to inject useful context or transactions. However, since Medusa can't detect whether the method is asynchronus, it always executes methods in the wrapper with the `await` keyword.
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For example, if you have a synchronous `getMessage` method, and you use it other resources like workflows, Medusa executes it as an async method:
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```ts
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await helloModuleService.getMessage()
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```
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So, make sure your service's methods are always async to avoid unexpected errors or behavior.
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```ts highlights={[["8", "", "Method must be async."], ["13", "async", "Correct way of defining the method."]]}
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import { MedusaService } from "@medusajs/framework/utils"
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import MyCustom from "./models/my-custom"
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class HelloModuleService extends MedusaService({
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MyCustom,
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}){
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// Don't
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getMessage(): string {
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return "Hello, World!"
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}
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// Do
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async getMessage(): Promise<string> {
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return "Hello, World!"
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}
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}
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export default HelloModuleService
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```
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