Feat: @medusajs/workflows (#4553)

feat: medusa workflows

packages/workflows/src/helper/pipe.ts

@@ -0,0 +1,98 @@
+import { Context, MedusaContainer, SharedContext } from "@medusajs/types"
+import {
+  TransactionMetadata,
+  WorkflowStepHandler,
+} from "@medusajs/orchestration"
+
+import { InputAlias } from "../definitions"
+
+type WorkflowStepReturn = {
+  alias: string
+  value: any
+}
+
+type WorkflowStepInput = {
+  from: string
+  alias: string
+}
+
+interface PipelineInput {
+  inputAlias?: InputAlias | string
+  invoke?: WorkflowStepInput | WorkflowStepInput[]
+  compensate?: WorkflowStepInput | WorkflowStepInput[]
+}
+
+export type WorkflowArguments = {
+  container: MedusaContainer
+  payload: unknown
+  data: any
+  metadata: TransactionMetadata
+  context: Context | SharedContext
+}
+
+export type PipelineHandler = (
+  args: WorkflowArguments
+) => Promise<WorkflowStepReturn | WorkflowStepReturn[]>
+
+export function pipe(
+  input: PipelineInput,
+  ...functions: PipelineHandler[]
+): WorkflowStepHandler {
+  return async ({
+    container,
+    payload,
+    invoke,
+    compensate,
+    metadata,
+    context,
+  }) => {
+    const data = {}
+
+    const original = {
+      invoke: invoke ?? {},
+      compensate: compensate ?? {},
+    }
+
+    if (input.inputAlias) {
+      Object.assign(original.invoke, { [input.inputAlias]: payload })
+    }
+
+    for (const key in input) {
+      if (!input[key]) {
+        continue
+      }
+
+      if (!Array.isArray(input[key])) {
+        input[key] = [input[key]]
+      }
+
+      for (const action of input[key]) {
+        if (action?.alias) {
+          data[action.alias] = original[key][action.from]
+        }
+      }
+    }
+
+    return functions.reduce(async (_, fn) => {
+      let result = await fn({
+        container,
+        payload,
+        data,
+        metadata,
+        context: context as Context,
+      })
+
+      if (Array.isArray(result)) {
+        for (const action of result) {
+          if (action?.alias) {
+            data[action.alias] = action.value
+          }
+        }
+      } else if (result?.alias) {
+        data[result.alias] = result.value
+      }
+
+      return result
+    }, {})
+  }
+}