feat(tax): add endpoints to manage tax rate rules (#6557)

**What**
Adds endpoints to manage tax rules on a tax rate:
- Create a tax rule: POST /admin/tax-rates/:id/rules 
- Delete a tax rule: DELETE /admin/tax-rates/:id/rules/:rule_id
- Replace tax rules: POST /admin/tax-rates/:id -- with { rules: [...] } in body.

### Noteworthy things I bumped into

**Updating nested relationships**
A TaxRate can have multiple TaxRules and in this PR we enable users to replace all TaxRules associated with a TaxRate in one operation. If working with the module directly this can be done with:

```javascript
taxModuleService.update(rateId, { rules: [{ ... }] })
```

Internally in the `update` function the TaxModule first soft deletes any TaxRules that exist on the TaxRate and then creates new TaxRules for the passed rules ([see test](https://github.com/medusajs/medusa/pull/6557/files#diff-cdcbab80ac7928b80648088ec57a3ab09dddd4409d6afce034f2caff08ee022bR78)).

A challenge arises when doing this in a compensatable way in a workflow. To see this imagine the following:
1. `updateTaxRatesWorkflow` gets the current data for the tax rates to update. This includes the tax rates' rules.
2. `updateTaxRatesWorkflow` calls `taxModuleService.update` with new rules. 
3. Internally, the tax module deletes the rules in 1. and creates new rules.
4. Imagine an error happens in a following step and the workflow has to compensate.
5. The workflow uses the data from 1. and calls upsert. The tax module may correctly update the previous tax rules so they are no longer soft deleted. However, upsert (at least not by default) doesn't delete the new rules that were created in 2.

As illustrated by 5. compensating the update is not pretty. To get around this I instead opted to let the workflow handle setting the rules for a rate that makes the compensation more straightforward to handle. [See workflow here](https://github.com/medusajs/medusa/pull/6557/files#diff-ff19e1f2fa32289aefff90d33c05c154f9605a3c5da6a62683071a1fcaedfd7bR89).

**Using nested workflows**
Initially, I wanted to use the `setTaxRateRulesWorkflow` within the `updateTaxRatesWorkflow`. And this worked great for the invoke phase. However, when I needed to compensate the update workflow (and hence also had to compensate the set rules workflow), I found that the workflow engine no longer had the set rules transaction in memory and therefore could not roll it back. ([This is where I try to rollback](https://github.com/medusajs/medusa/pull/6557/files#diff-ff19e1f2fa32289aefff90d33c05c154f9605a3c5da6a62683071a1fcaedfd7bR62), but the transaction id can't be found).

I therefore opted to copy the steps from the set tax rate rules workflow into the update tax rates workflow; however, once we figure out a good way to ensure we can compensate nested workflows we should move to the nested workflow instead. 

This also made me realize that the current implementation of workflows that use `refreshCartPromotions` may create inconsistencies in case of failures (cc: @riqwan).

integration-tests/modules/__tests__/tax/admin/tax.spec.ts

@@ -373,4 +373,139 @@ describe("Taxes - Admin", () => {
     expect(rates.length).toEqual(1)
     expect(rates[0].deleted_at).not.toBeNull()
   })
+
+  it("can create a tax rate add rules and remove them", async () => {
+    const api = useApi() as any
+    const regionRes = await api.post(
+      `/admin/tax-regions`,
+      {
+        country_code: "us",
+        default_tax_rate: { code: "default", rate: 2, name: "default rate" },
+      },
+      adminHeaders
+    )
+
+    const usRegionId = regionRes.data.tax_region.id
+    const rateRes = await api.post(
+      `/admin/tax-rates`,
+      {
+        tax_region_id: usRegionId,
+        code: "RATE2",
+        name: "another rate",
+        rate: 10,
+        rules: [{ reference: "product", reference_id: "prod_1234" }],
+      },
+      adminHeaders
+    )
+    const rateId = rateRes.data.tax_rate.id
+    let rules = await service.listTaxRateRules({ tax_rate_id: rateId })
+
+    expect(rules).toEqual([
+      {
+        id: expect.any(String),
+        tax_rate_id: rateId,
+        reference: "product",
+        reference_id: "prod_1234",
+        created_by: "admin_user",
+        created_at: expect.any(Date),
+        updated_at: expect.any(Date),
+        deleted_at: null,
+        tax_rate: { id: rateId },
+        metadata: null,
+      },
+    ])
+
+    await api.post(
+      `/admin/tax-rates/${rateId}/rules`,
+      {
+        reference: "product",
+        reference_id: "prod_1111",
+      },
+      adminHeaders
+    )
+
+    await api.post(
+      `/admin/tax-rates/${rateId}/rules`,
+      {
+        reference: "product",
+        reference_id: "prod_2222",
+      },
+      adminHeaders
+    )
+    rules = await service.listTaxRateRules({ tax_rate_id: rateId })
+    expect(rules).toEqual(
+      expect.arrayContaining([
+        expect.objectContaining({
+          tax_rate_id: rateId,
+          reference: "product",
+          reference_id: "prod_1234",
+          created_by: "admin_user",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateId,
+          reference: "product",
+          reference_id: "prod_1111",
+          created_by: "admin_user",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateId,
+          reference: "product",
+          reference_id: "prod_2222",
+          created_by: "admin_user",
+        }),
+      ])
+    )
+
+    const toDeleteId = rules.find((r) => r.reference_id === "prod_1111")!.id
+    await api.delete(
+      `/admin/tax-rates/${rateId}/rules/${toDeleteId}`,
+      adminHeaders
+    )
+
+    rules = await service.listTaxRateRules({ tax_rate_id: rateId })
+    expect(rules.length).toEqual(2)
+
+    await api.post(
+      `/admin/tax-rates/${rateId}`,
+      {
+        rules: [
+          { reference: "product", reference_id: "prod_3333" },
+          { reference: "product", reference_id: "prod_4444" },
+          { reference: "product", reference_id: "prod_5555" },
+          { reference: "product", reference_id: "prod_6666" },
+        ],
+      },
+      adminHeaders
+    )
+    rules = await service.listTaxRateRules({ tax_rate_id: rateId })
+    expect(rules.length).toEqual(4)
+    expect(rules).toEqual(
+      expect.arrayContaining([
+        expect.objectContaining({
+          tax_rate_id: rateId,
+          reference: "product",
+          reference_id: "prod_3333",
+          created_by: "admin_user",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateId,
+          reference: "product",
+          reference_id: "prod_4444",
+          created_by: "admin_user",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateId,
+          reference: "product",
+          reference_id: "prod_5555",
+          created_by: "admin_user",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateId,
+          reference: "product",
+          reference_id: "prod_6666",
+          created_by: "admin_user",
+        }),
+      ])
+    )
+  })
 })

integration-tests/modules/__tests__/tax/workflow/tax.spec.ts

@@ -0,0 +1,209 @@
+import path from "path"
+import { ITaxModuleService } from "@medusajs/types"
+import { ModuleRegistrationName } from "@medusajs/modules-sdk"
+
+import { createAdminUser } from "../../../helpers/create-admin-user"
+import { initDb, useDb } from "../../../../environment-helpers/use-db"
+import { getContainer } from "../../../../environment-helpers/use-container"
+import { startBootstrapApp } from "../../../../environment-helpers/bootstrap-app"
+import { useApi } from "../../../../environment-helpers/use-api"
+import {
+  createTaxRateRulesStepId,
+  maybeSetTaxRateRulesStepId,
+  updateTaxRatesStepId,
+  updateTaxRatesWorkflow,
+} from "@medusajs/core-flows"
+
+jest.setTimeout(50000)
+
+const env = { MEDUSA_FF_MEDUSA_V2: true }
+const adminHeaders = {
+  headers: { "x-medusa-access-token": "test_token" },
+}
+
+describe("Taxes - Workflow", () => {
+  let dbConnection
+  let appContainer
+  let shutdownServer
+  let service: ITaxModuleService
+
+  beforeAll(async () => {
+    const cwd = path.resolve(path.join(__dirname, "..", "..", ".."))
+    dbConnection = await initDb({ cwd, env } as any)
+    shutdownServer = await startBootstrapApp({ cwd, env })
+    appContainer = getContainer()
+    service = appContainer.resolve(ModuleRegistrationName.TAX)
+  })
+
+  beforeEach(async () => {
+    await createAdminUser(dbConnection, adminHeaders)
+  })
+
+  afterAll(async () => {
+    const db = useDb()
+    await db.shutdown()
+    await shutdownServer()
+  })
+
+  afterEach(async () => {
+    const db = useDb()
+    await db.teardown()
+  })
+
+  it("compensates rules correctly", async () => {
+    const taxRegion = await service.createTaxRegions({
+      country_code: "us",
+    })
+
+    const [rateOne, rateTwo] = await service.create([
+      {
+        tax_region_id: taxRegion.id,
+        rate: 10,
+        code: "standard",
+        name: "Standard",
+        rules: [
+          { reference: "shipping", reference_id: "shipping_12354" },
+          { reference: "shipping", reference_id: "shipping_11111" },
+          { reference: "shipping", reference_id: "shipping_22222" },
+        ],
+      },
+      {
+        tax_region_id: taxRegion.id,
+        rate: 2,
+        code: "reduced",
+        name: "Reduced",
+        rules: [
+          { reference: "product", reference_id: "product_12354" },
+          { reference: "product", reference_id: "product_11111" },
+          { reference: "product", reference_id: "product_22222" },
+        ],
+      },
+    ])
+
+    const workflow = updateTaxRatesWorkflow(appContainer)
+
+    workflow.appendAction("throw", createTaxRateRulesStepId, {
+      invoke: async function failStep() {
+        throw new Error(`Failed to update`)
+      },
+    })
+
+    await workflow.run({
+      input: {
+        selector: { tax_region_id: taxRegion.id },
+        update: {
+          rate: 2,
+          rules: [
+            { reference: "product", reference_id: "product_12354" },
+            { reference: "shipping", reference_id: "shipping_12354" },
+          ],
+        },
+      },
+      throwOnError: false,
+    })
+
+    const taxRateRules = await service.listTaxRateRules({
+      tax_rate: { tax_region_id: taxRegion.id },
+    })
+
+    expect(taxRateRules.length).toEqual(6)
+    expect(taxRateRules).toEqual(
+      expect.arrayContaining([
+        expect.objectContaining({
+          tax_rate_id: rateOne.id,
+          reference_id: "shipping_12354",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateOne.id,
+          reference_id: "shipping_11111",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateOne.id,
+          reference_id: "shipping_22222",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateTwo.id,
+          reference_id: "product_12354",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateTwo.id,
+          reference_id: "product_11111",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateTwo.id,
+          reference_id: "product_22222",
+        }),
+      ])
+    )
+  })
+
+  it("creates rules correctly", async () => {
+    const taxRegion = await service.createTaxRegions({
+      country_code: "us",
+    })
+
+    const [rateOne, rateTwo] = await service.create([
+      {
+        tax_region_id: taxRegion.id,
+        rate: 10,
+        code: "standard",
+        name: "Standard",
+        rules: [
+          { reference: "shipping", reference_id: "shipping_12354" },
+          { reference: "shipping", reference_id: "shipping_11111" },
+          { reference: "shipping", reference_id: "shipping_22222" },
+        ],
+      },
+      {
+        tax_region_id: taxRegion.id,
+        rate: 2,
+        code: "reduced",
+        name: "Reduced",
+        rules: [
+          { reference: "product", reference_id: "product_12354" },
+          { reference: "product", reference_id: "product_11111" },
+          { reference: "product", reference_id: "product_22222" },
+        ],
+      },
+    ])
+
+    await updateTaxRatesWorkflow(appContainer).run({
+      input: {
+        selector: { tax_region_id: taxRegion.id },
+        update: {
+          rate: 2,
+          rules: [
+            { reference: "product", reference_id: "product_12354" },
+            { reference: "shipping", reference_id: "shipping_12354" },
+          ],
+        },
+      },
+    })
+
+    const taxRateRules = await service.listTaxRateRules({
+      tax_rate: { tax_region_id: taxRegion.id },
+    })
+
+    expect(taxRateRules.length).toEqual(4)
+    expect(taxRateRules).toEqual(
+      expect.arrayContaining([
+        expect.objectContaining({
+          tax_rate_id: rateOne.id,
+          reference_id: "shipping_12354",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateTwo.id,
+          reference_id: "shipping_12354",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateOne.id,
+          reference_id: "product_12354",
+        }),
+        expect.objectContaining({
+          tax_rate_id: rateTwo.id,
+          reference_id: "product_12354",
+        }),
+      ])
+    )
+  })
+})

packages/core-flows/src/tax/steps/create-tax-rate-rules.ts

@@ -0,0 +1,31 @@
+import { ModuleRegistrationName } from "@medusajs/modules-sdk"
+import { CreateTaxRateRuleDTO, ITaxModuleService } from "@medusajs/types"
+import { StepResponse, createStep } from "@medusajs/workflows-sdk"
+
+export const createTaxRateRulesStepId = "create-tax-rate-rules"
+export const createTaxRateRulesStep = createStep(
+  createTaxRateRulesStepId,
+  async (data: CreateTaxRateRuleDTO[], { container }) => {
+    const service = container.resolve<ITaxModuleService>(
+      ModuleRegistrationName.TAX
+    )
+
+    const created = await service.createTaxRateRules(data)
+
+    return new StepResponse(
+      created,
+      created.map((rule) => rule.id)
+    )
+  },
+  async (createdIds, { container }) => {
+    if (!createdIds?.length) {
+      return
+    }
+
+    const service = container.resolve<ITaxModuleService>(
+      ModuleRegistrationName.TAX
+    )
+
+    await service.deleteTaxRateRules(createdIds)
+  }
+)

packages/core-flows/src/tax/steps/delete-tax-rate-rules.ts

@@ -0,0 +1,32 @@
+import { ModuleRegistrationName } from "@medusajs/modules-sdk"
+import { ITaxModuleService } from "@medusajs/types"
+import { StepResponse, createStep } from "@medusajs/workflows-sdk"
+
+export const deleteTaxRateRulesStepId = "delete-tax-rate-rules"
+export const deleteTaxRateRulesStep = createStep(
+  deleteTaxRateRulesStepId,
+  async (ids: string[], { container }) => {
+    if (!ids?.length) {
+      return new StepResponse(void 0, [])
+    }
+
+    const service = container.resolve<ITaxModuleService>(
+      ModuleRegistrationName.TAX
+    )
+
+    await service.softDeleteTaxRateRules(ids)
+
+    return new StepResponse(void 0, ids)
+  },
+  async (prevIds, { container }) => {
+    if (!prevIds?.length) {
+      return
+    }
+
+    const service = container.resolve<ITaxModuleService>(
+      ModuleRegistrationName.TAX
+    )
+
+    await service.restoreTaxRateRules(prevIds)
+  }
+)

packages/core-flows/src/tax/steps/index.ts

@@ -3,3 +3,7 @@ export * from "./delete-tax-regions"
 export * from "./create-tax-rates"
 export * from "./update-tax-rates"
 export * from "./delete-tax-rates"
+export * from "./delete-tax-rate-rules"
+export * from "./create-tax-rate-rules"
+export * from "./list-tax-rate-rule-ids"
+export * from "./list-tax-rate-ids"

packages/core-flows/src/tax/steps/list-tax-rate-ids.ts

@@ -0,0 +1,23 @@
+import { createStep, StepResponse } from "@medusajs/workflows-sdk"
+import { FilterableTaxRateProps, ITaxModuleService } from "@medusajs/types"
+import { ModuleRegistrationName } from "@medusajs/modules-sdk"
+
+type StepInput = {
+  selector: FilterableTaxRateProps
+}
+
+export const listTaxRateIdsStepId = "list-tax-rate-ids"
+export const listTaxRateIdsStep = createStep(
+  listTaxRateIdsStepId,
+  async (input: StepInput, { container }) => {
+    const service = container.resolve<ITaxModuleService>(
+      ModuleRegistrationName.TAX
+    )
+
+    const rates = await service.list(input.selector, {
+      select: ["id"],
+    })
+
+    return new StepResponse(rates.map((r) => r.id))
+  }
+)

packages/core-flows/src/tax/steps/list-tax-rate-rule-ids.ts

@@ -0,0 +1,22 @@
+import { createStep, StepResponse } from "@medusajs/workflows-sdk"
+import { FilterableTaxRateRuleProps, ITaxModuleService } from "@medusajs/types"
+import { ModuleRegistrationName } from "@medusajs/modules-sdk"
+
+type StepInput = {
+  selector: FilterableTaxRateRuleProps
+}
+
+export const listTaxRateRuleIdsStepId = "list-tax-rate-rule-ids"
+export const listTaxRateRuleIdsStep = createStep(
+  listTaxRateRuleIdsStepId,
+  async (input: StepInput, { container }) => {
+    const service = container.resolve<ITaxModuleService>(
+      ModuleRegistrationName.TAX
+    )
+
+    const rules = await service.listTaxRateRules(input.selector, {
+      select: ["id"],
+    })
+    return new StepResponse(rules.map((r) => r.id))
+  }
+)

packages/core-flows/src/tax/workflows/create-tax-rate-rules.ts

@@ -0,0 +1,15 @@
+import { CreateTaxRateRuleDTO, TaxRateRuleDTO } from "@medusajs/types"
+import { WorkflowData, createWorkflow } from "@medusajs/workflows-sdk"
+import { createTaxRateRulesStep } from "../steps"
+
+type WorkflowInput = {
+  rules: CreateTaxRateRuleDTO[]
+}
+
+export const createTaxRateRulesWorkflowId = "create-tax-rate-rules"
+export const createTaxRateRulesWorkflow = createWorkflow(
+  createTaxRateRulesWorkflowId,
+  (input: WorkflowData<WorkflowInput>): WorkflowData<TaxRateRuleDTO[]> => {
+    return createTaxRateRulesStep(input.rules)
+  }
+)

packages/core-flows/src/tax/workflows/delete-tax-rate-rules.ts

@@ -0,0 +1,12 @@
+import { WorkflowData, createWorkflow } from "@medusajs/workflows-sdk"
+import { deleteTaxRateRulesStep } from "../steps"
+
+type WorkflowInput = { ids: string[] }
+
+export const deleteTaxRateRulesWorkflowId = "delete-tax-rate-rules"
+export const deleteTaxRateRulesWorkflow = createWorkflow(
+  deleteTaxRateRulesWorkflowId,
+  (input: WorkflowData<WorkflowInput>): WorkflowData<void> => {
+    return deleteTaxRateRulesStep(input.ids)
+  }
+)

packages/core-flows/src/tax/workflows/index.ts

@@ -3,3 +3,6 @@ export * from "./delete-tax-regions"
 export * from "./create-tax-rates"
 export * from "./update-tax-rates"
 export * from "./delete-tax-rates"
+export * from "./set-tax-rate-rules"
+export * from "./create-tax-rate-rules"
+export * from "./delete-tax-rate-rules"

packages/core-flows/src/tax/workflows/set-tax-rate-rules.ts

@@ -0,0 +1,46 @@
+import { CreateTaxRateRuleDTO, TaxRateRuleDTO } from "@medusajs/types"
+import {
+  WorkflowData,
+  createWorkflow,
+  transform,
+} from "@medusajs/workflows-sdk"
+import {
+  createTaxRateRulesStep,
+  deleteTaxRateRulesStep,
+  listTaxRateRuleIdsStep,
+} from "../steps"
+
+type WorkflowInput = {
+  tax_rate_ids: string[]
+  rules: Omit<CreateTaxRateRuleDTO, "tax_rate_id">[]
+}
+
+export const setTaxRateRulesWorkflowId = "set-tax-rate-rules"
+export const setTaxRateRulesWorkflow = createWorkflow(
+  setTaxRateRulesWorkflowId,
+  (input: WorkflowData<WorkflowInput>): WorkflowData<TaxRateRuleDTO[]> => {
+    const ruleIds = listTaxRateRuleIdsStep({
+      selector: { tax_rate_id: input.tax_rate_ids },
+    })
+
+    deleteTaxRateRulesStep(ruleIds)
+
+    const rulesWithRateId = transform(
+      { rules: input.rules, rateIds: input.tax_rate_ids },
+      ({ rules, rateIds }) => {
+        return rules
+          .map((r) => {
+            return rateIds.map((id) => {
+              return {
+                ...r,
+                tax_rate_id: id,
+              }
+            })
+          })
+          .flat()
+      }
+    )
+
+    return createTaxRateRulesStep(rulesWithRateId)
+  }
+)

packages/core-flows/src/tax/workflows/update-tax-rates.ts

@@ -1,10 +1,23 @@
 import {
   FilterableTaxRateProps,
+  ITaxModuleService,
   TaxRateDTO,
   UpdateTaxRateDTO,
 } from "@medusajs/types"
-import { WorkflowData, createWorkflow } from "@medusajs/workflows-sdk"
-import { updateTaxRatesStep } from "../steps"
+import {
+  StepResponse,
+  WorkflowData,
+  createStep,
+  createWorkflow,
+  transform,
+} from "@medusajs/workflows-sdk"
+import {
+  createTaxRateRulesStep,
+  deleteTaxRateRulesStep,
+  updateTaxRatesStep,
+} from "../steps"
+import { ModuleRegistrationName } from "@medusajs/modules-sdk"
+// import { setTaxRateRulesWorkflow } from "./set-tax-rate-rules"
 
 type UpdateTaxRatesStepInput = {
   selector: FilterableTaxRateProps
@@ -13,10 +26,125 @@ type UpdateTaxRatesStepInput = {
 
 type WorkflowInput = UpdateTaxRatesStepInput
 
+type StepInput = {
+  tax_rate_ids: string[]
+  update: UpdateTaxRateDTO
+}
+
+// TODO: When we figure out how to compensate nested workflows, we can use this
+//
+// export const maybeSetTaxRateRulesStepId = "maybe-set-tax-rate-rules"
+// const maybeSetTaxRateRules = createStep(
+//   maybeSetTaxRateRulesStepId,
+//   async (input: StepInput, { container }) => {
+//     const { update } = input
+//
+//     if (!update.rules) {
+//       return new StepResponse([], "")
+//     }
+//
+//     const { result, transaction } = await setTaxRateRulesWorkflow(
+//       container
+//     ).run({
+//       input: {
+//         tax_rate_ids: input.tax_rate_ids,
+//         rules: update.rules,
+//       },
+//     })
+//
+//     return new StepResponse(result, transaction.transactionId)
+//   },
+//   async (transactionId, { container }) => {
+//     if (!transactionId) {
+//       return
+//     }
+//
+//     await setTaxRateRulesWorkflow(container).cancel(transactionId)
+//   }
+// )
+
+const maybeListTaxRateRuleIdsStepId = "maybe-list-tax-rate-rule-ids"
+const maybeListTaxRateRuleIdsStep = createStep(
+  maybeListTaxRateRuleIdsStepId,
+  async (input: StepInput, { container }) => {
+    const { update, tax_rate_ids } = input
+
+    if (!update.rules) {
+      return new StepResponse([])
+    }
+
+    const service = container.resolve<ITaxModuleService>(
+      ModuleRegistrationName.TAX
+    )
+
+    const rules = await service.listTaxRateRules(
+      { tax_rate_id: tax_rate_ids },
+      { select: ["id"] }
+    )
+
+    return new StepResponse(rules.map((r) => r.id))
+  }
+)
+
 export const updateTaxRatesWorkflowId = "update-tax-rates"
 export const updateTaxRatesWorkflow = createWorkflow(
   updateTaxRatesWorkflowId,
   (input: WorkflowData<WorkflowInput>): WorkflowData<TaxRateDTO[]> => {
-    return updateTaxRatesStep(input)
+    const cleanedUpdateInput = transform(input, (data) => {
+      // Transform clones data so we can safely modify it
+      if (data.update.rules) {
+        delete data.update.rules
+      }
+
+      return {
+        selector: data.selector,
+        update: data.update,
+      }
+    })
+
+    const updatedRates = updateTaxRatesStep(cleanedUpdateInput)
+    const rateIds = transform(updatedRates, (rates) => rates.map((r) => r.id))
+
+    // TODO: Use when we figure out how to compensate nested workflows
+    // maybeSetTaxRateRules({
+    //   tax_rate_ids: rateIds,
+    //   update: input.update,
+    // })
+
+    // COPY-PASTE from set-tax-rate-rules.ts
+    const ruleIds = maybeListTaxRateRuleIdsStep({
+      tax_rate_ids: rateIds,
+      update: input.update,
+    })
+
+    deleteTaxRateRulesStep(ruleIds)
+
+    const rulesWithRateId = transform(
+      { update: input.update, rateIds },
+      ({ update, rateIds }) => {
+        if (!update.rules) {
+          return []
+        }
+
+        const updatedBy = update.updated_by
+
+        return update.rules
+          .map((r) => {
+            return rateIds.map((id) => {
+              return {
+                ...r,
+                created_by: updatedBy,
+                tax_rate_id: id,
+              }
+            })
+          })
+          .flat()
+      }
+    )
+
+    createTaxRateRulesStep(rulesWithRateId)
+    // end of COPY-PASTE from set-tax-rate-rules.ts
+
+    return updatedRates
   }
 )

packages/medusa/src/api-v2/admin/tax-rates/[id]/route.ts

@@ -18,7 +18,7 @@ export const POST = async (
   const { errors } = await updateTaxRatesWorkflow(req.scope).run({
     input: {
       selector: { id: req.params.id },
-      update: req.validatedBody,
+      update: { ...req.validatedBody, updated_by: req.auth.actor_id },
     },
     throwOnError: false,
   })

packages/medusa/src/api-v2/admin/tax-rates/[id]/rules/[rule_id]/route.ts

@@ -0,0 +1,33 @@
+import { deleteTaxRateRulesWorkflow } from "@medusajs/core-flows"
+import { remoteQueryObjectFromString } from "@medusajs/utils"
+import { defaultAdminTaxRatesFields } from "../../../../../../api/routes/admin/tax-rates"
+import {
+  AuthenticatedMedusaRequest,
+  MedusaResponse,
+} from "../../../../../../types/routing"
+
+export const DELETE = async (
+  req: AuthenticatedMedusaRequest,
+  res: MedusaResponse
+) => {
+  const { errors } = await deleteTaxRateRulesWorkflow(req.scope).run({
+    input: { ids: [req.params.rule_id] },
+    throwOnError: false,
+  })
+
+  if (Array.isArray(errors) && errors[0]) {
+    throw errors[0].error
+  }
+
+  const remoteQuery = req.scope.resolve("remoteQuery")
+
+  const queryObject = remoteQueryObjectFromString({
+    entryPoint: "tax_rate",
+    variables: { id: req.params.id },
+    fields: defaultAdminTaxRatesFields,
+  })
+
+  const [taxRate] = await remoteQuery(queryObject)
+
+  res.status(200).json({ tax_rate: taxRate })
+}

packages/medusa/src/api-v2/admin/tax-rates/[id]/rules/route.ts

@@ -0,0 +1,42 @@
+import { createTaxRateRulesWorkflow } from "@medusajs/core-flows"
+import { remoteQueryObjectFromString } from "@medusajs/utils"
+import { defaultAdminTaxRatesFields } from "../../../../../api/routes/admin/tax-rates"
+import {
+  AuthenticatedMedusaRequest,
+  MedusaResponse,
+} from "../../../../../types/routing"
+import { AdminPostTaxRatesTaxRateRulesReq } from "../../validators"
+
+export const POST = async (
+  req: AuthenticatedMedusaRequest<AdminPostTaxRatesTaxRateRulesReq>,
+  res: MedusaResponse
+) => {
+  const { errors } = await createTaxRateRulesWorkflow(req.scope).run({
+    input: {
+      rules: [
+        {
+          ...req.validatedBody,
+          tax_rate_id: req.params.id,
+          created_by: req.auth.actor_id,
+        },
+      ],
+    },
+    throwOnError: false,
+  })
+
+  if (Array.isArray(errors) && errors[0]) {
+    throw errors[0].error
+  }
+
+  const remoteQuery = req.scope.resolve("remoteQuery")
+
+  const queryObject = remoteQueryObjectFromString({
+    entryPoint: "tax_rate",
+    variables: { id: req.params.id },
+    fields: defaultAdminTaxRatesFields,
+  })
+
+  const [taxRate] = await remoteQuery(queryObject)
+
+  res.status(200).json({ tax_rate: taxRate })
+}

packages/medusa/src/api-v2/admin/tax-rates/middlewares.ts

@@ -4,6 +4,7 @@ import {
   AdminGetTaxRatesTaxRateParams,
   AdminPostTaxRatesReq,
   AdminPostTaxRatesTaxRateReq,
+  AdminPostTaxRatesTaxRateRulesReq,
 } from "./validators"
 import { transformBody, transformQuery } from "../../../api/middlewares"
 
@@ -36,4 +37,9 @@ export const adminTaxRateRoutesMiddlewares: MiddlewareRoute[] = [
       ),
     ],
   },
+  {
+    method: "POST",
+    matcher: "/admin/tax-rates/:id/rules",
+    middlewares: [transformBody(AdminPostTaxRatesTaxRateRulesReq)],
+  },
 ]

packages/medusa/src/api-v2/admin/tax-rates/validators.ts

@@ -65,6 +65,10 @@ export class AdminPostTaxRatesTaxRateReq {
   @IsOptional()
   name?: string
 
+  @ValidateNested({ each: true })
+  @Type(() => CreateTaxRateRule)
+  rules: CreateTaxRateRule[]
+
   @IsBoolean()
   @IsOptional()
   is_default?: boolean
@@ -77,3 +81,5 @@ export class AdminPostTaxRatesTaxRateReq {
   @IsOptional()
   metadata?: Record<string, unknown>
 }
+
+export class AdminPostTaxRatesTaxRateRulesReq extends CreateTaxRateRule {}

packages/medusa/src/loaders/api.ts

@@ -47,7 +47,9 @@ export default async ({
         configModule,
       }).load()
     } catch (err) {
-      throw Error("An error occurred while registering Medusa Core API Routes")
+      throw Error(
+        "An error occurred while registering Medusa Core API Routes. See error in logs for more details."
+      )
     }
   } else {
     app.use(bodyParser.json())

packages/tax/integration-tests/__tests__/index.spec.ts

@@ -75,6 +75,89 @@ moduleIntegrationTestRunner({
         )
       })
 
+      it("should update tax rates with rules", async () => {
+        const region = await service.createTaxRegions({
+          country_code: "US",
+          default_tax_rate: {
+            name: "Test Rate",
+            rate: 0.2,
+          },
+        })
+
+        const rate = await service.create({
+          tax_region_id: region.id,
+          name: "Shipping Rate",
+          code: "test",
+          rate: 8.23,
+        })
+
+        await service.update(rate.id, {
+          name: "Updated Rate",
+          code: "TEST",
+          rate: 8.25,
+          rules: [
+            { reference: "product", reference_id: "product_id_1" },
+            { reference: "product_type", reference_id: "product_type_id" },
+          ],
+        })
+
+        const rules = await service.listTaxRateRules({ tax_rate_id: rate.id })
+
+        expect(rules).toEqual(
+          expect.arrayContaining([
+            expect.objectContaining({
+              reference: "product",
+              reference_id: "product_id_1",
+            }),
+            expect.objectContaining({
+              reference: "product_type",
+              reference_id: "product_type_id",
+            }),
+          ])
+        )
+
+        await service.update(rate.id, {
+          rules: [
+            { reference: "product", reference_id: "product_id_1" },
+            { reference: "product", reference_id: "product_id_2" },
+            { reference: "product_type", reference_id: "product_type_id_2" },
+            { reference: "product_type", reference_id: "product_type_id_3" },
+          ],
+        })
+
+        const rulesWithDeletes = await service.listTaxRateRules(
+          { tax_rate_id: rate.id },
+          { withDeleted: true }
+        )
+
+        expect(rulesWithDeletes).toEqual(
+          expect.arrayContaining([
+            expect.objectContaining({
+              reference: "product",
+              reference_id: "product_id_2",
+            }),
+            expect.objectContaining({
+              reference: "product_type",
+              reference_id: "product_type_id_2",
+            }),
+            expect.objectContaining({
+              reference: "product_type",
+              reference_id: "product_type_id_3",
+            }),
+            expect.objectContaining({
+              reference: "product",
+              reference_id: "product_id_1",
+              deleted_at: expect.any(Date),
+            }),
+            expect.objectContaining({
+              reference: "product_type",
+              reference_id: "product_type_id",
+              deleted_at: expect.any(Date),
+            }),
+          ])
+        )
+      })
+
       it("should create a tax region", async () => {
         const region = await service.createTaxRegions({
           country_code: "US",

packages/tax/src/models/tax-rate-rule.ts

@@ -105,11 +105,11 @@ export default class TaxRateRule {
 
   @BeforeCreate()
   onCreate() {
-    this.id = generateEntityId(this.id, "txr")
+    this.id = generateEntityId(this.id, "txrule")
   }
 
   @OnInit()
   onInit() {
-    this.id = generateEntityId(this.id, "txr")
+    this.id = generateEntityId(this.id, "txrule")
   }
 }

packages/tax/src/models/tax-rate.ts

@@ -79,6 +79,7 @@ export default class TaxRate {
 
   @OneToMany(() => TaxRateRule, (rule) => rule.tax_rate, {
     cascade: ["soft-remove" as Cascade],
+    persist: false,
   })
   rules = new Collection<TaxRateRule>(this)
 

packages/tax/src/services/tax-module-service.ts

@@ -22,6 +22,7 @@ import {
 import { TaxProvider, TaxRate, TaxRegion, TaxRateRule } from "@models"
 import { entityNameToLinkableKeysMap, joinerConfig } from "../joiner-config"
 import { TaxRegionDTO } from "@medusajs/types"
+import { EntityManager } from "@mikro-orm/postgresql"
 
 type InjectedDependencies = {
   baseRepository: DAL.RepositoryService
@@ -135,6 +136,7 @@ export default class TaxModuleService<
             rateRules.map((r) => {
               return {
                 ...r,
+                created_by: rate.created_by,
                 tax_rate_id: rate.id,
               }
             })
@@ -193,9 +195,85 @@ export default class TaxModuleService<
         ? { id: idOrSelector }
         : idOrSelector
 
+    if (data.rules) {
+      await this.setTaxRateRulesForTaxRates(
+        idOrSelector,
+        data.rules,
+        data.updated_by,
+        sharedContext
+      )
+
+      delete data.rules
+    }
+
     return await this.taxRateService_.update({ selector, data }, sharedContext)
   }
 
+  private async setTaxRateRulesForTaxRates(
+    idOrSelector: string | string[] | TaxTypes.FilterableTaxRateProps,
+    rules: Omit<TaxTypes.CreateTaxRateRuleDTO, "tax_rate_id">[],
+    createdBy?: string,
+    sharedContext: Context = {}
+  ) {
+    const selector =
+      Array.isArray(idOrSelector) || isString(idOrSelector)
+        ? { id: idOrSelector }
+        : idOrSelector
+
+    await this.taxRateRuleService_.softDelete(
+      { tax_rate: selector },
+      sharedContext
+    )
+
+    // TODO: this is a temporary solution seems like mikro-orm doesn't persist
+    // the soft delete which results in the creation below breaking the unique
+    // constraint
+    await this.taxRateRuleService_.list(
+      { tax_rate: selector },
+      { select: ["id"] },
+      sharedContext
+    )
+
+    if (rules.length === 0) {
+      return
+    }
+
+    const rateIds = await this.getTaxRateIdsFromSelector(idOrSelector)
+    const toCreate = rateIds
+      .map((id) => {
+        return rules.map((r) => {
+          return {
+            ...r,
+            created_by: createdBy,
+            tax_rate_id: id,
+          }
+        })
+      })
+      .flat()
+
+    return await this.createTaxRateRules(toCreate, sharedContext)
+  }
+
+  private async getTaxRateIdsFromSelector(
+    idOrSelector: string | string[] | TaxTypes.FilterableTaxRateProps,
+    sharedContext: Context = {}
+  ) {
+    if (Array.isArray(idOrSelector)) {
+      return idOrSelector
+    }
+
+    if (isString(idOrSelector)) {
+      return [idOrSelector]
+    }
+
+    const rates = await this.taxRateService_.list(
+      idOrSelector,
+      { select: ["id"] },
+      sharedContext
+    )
+    return rates.map((r) => r.id)
+  }
+
   async upsert(
     data: TaxTypes.UpsertTaxRateDTO[],
     sharedContext?: Context

packages/types/src/tax/common.ts

@@ -60,7 +60,7 @@ export interface TaxProviderDTO {
 export interface FilterableTaxRateProps
   extends BaseFilterable<FilterableTaxRateProps> {
   id?: string | string[]
-
+  tax_region_id?: string | string[]
   rate?: number | number[] | OperatorMap<number>
   code?: string | string[] | OperatorMap<string>
   name?: string | string[] | OperatorMap<string>
@@ -97,6 +97,7 @@ export interface FilterableTaxRegionProps
 }
 
 export interface TaxRateRuleDTO {
+  id: string
   reference: string
   reference_id: string
   tax_rate_id: string

packages/types/src/tax/mutations.ts

@@ -23,8 +23,10 @@ export interface UpdateTaxRateDTO {
   rate?: number | null
   code?: string | null
   name?: string
+  rules?: Omit<CreateTaxRateRuleDTO, "tax_rate_id">[]
   is_default?: boolean
-  created_by?: string
+  is_combinable?: boolean
+  updated_by?: string
   metadata?: Record<string, unknown>
 }
 
@@ -47,5 +49,5 @@ export interface CreateTaxRateRuleDTO {
   reference_id: string
   tax_rate_id: string
   metadata?: Record<string, unknown>
-  created_by?: string
+  created_by?: string | null
 }

packages/types/src/tax/service.ts

@@ -110,11 +110,11 @@ export interface ITaxModuleService extends IModuleService {
   ): Promise<TaxRateRuleDTO[]>
 
   deleteTaxRateRules(
-    taxRateRulePair: { tax_rate_id: string; reference_id: string },
+    taxRateRuleId: string,
     sharedContext?: Context
   ): Promise<void>
   deleteTaxRateRules(
-    taxRateRulePair: { tax_rate_id: string; reference_id: string }[],
+    taxRateRuleIds: string[],
     sharedContext?: Context
   ): Promise<void>
 
@@ -149,8 +149,14 @@ export interface ITaxModuleService extends IModuleService {
   ): Promise<Record<string, string[]> | void>
 
   softDeleteTaxRateRules<TReturnableLinkableKeys extends string = string>(
-    taxRateRulePairs: { tax_rate_id: string; reference_id: string }[],
+    taxRateRuleIds: string[],
     config?: SoftDeleteReturn<TReturnableLinkableKeys>,
     sharedContext?: Context
   ): Promise<Record<string, string[]> | void>
+
+  restoreTaxRateRules<TReturnableLinkableKeys extends string = string>(
+    taxRateRuleIds: string[],
+    config?: RestoreReturn<TReturnableLinkableKeys>,
+    sharedContext?: Context
+  ): Promise<Record<string, string[]> | void>
 }