Adapter swapping through Params.adapter.Model

package.json

@@ -2,7 +2,7 @@
   "name": "feathers-lowdb",
   "description": "A LowDB feathers database adapter service with yaml and json support",
   "type": "module",
-  "version": "1.0.0-alpha.8",
+  "version": "1.0.0-alpha.10",
   "homepage": "https://vblip.com",
   "main": "lib/src/index.js",
   "types": "lib/src/index.d.ts",

src/index.ts

@@ -22,11 +22,10 @@ export interface LowDBServiceStore<T> {
 
 export interface LowDBServiceOptions<T = any> extends AdapterServiceOptions {
   filename?: string
-  store?: LowDBServiceStore<T>
   startId?: number
   matcher?: (query: any) => any
   sorter?: (sort: any) => any,
-  Model?: Adapter<Record<string, any>>,
+  Model?: Low<Record<string, T>>,
   partition?: string
   waitForDisk?: Boolean
 }
@@ -58,24 +57,24 @@ const _select = (data: any, params: any, ...args: string[]) => {
   return base(JSON.parse(JSON.stringify(data)))
 }
 
-const genTempName = () => 
-  `${tmpdir()}/low-${new Date().toISOString()}-${(Math.random() * 9 ** 9) | 0 }`
+const genTempName = () =>
+  `${tmpdir()}/low-${new Date().toISOString()}-${(Math.random() * 9 ** 9) | 0}`
 
 export function yaml<T = any>(
   options: Partial<LowDBServiceOptions<T>> = {}
 ) {
   const filename =
-      options.filename ||
-      genTempName() + '.yaml'
+    options.filename ||
+    genTempName() + '.yaml'
   return new YAMLFile(filename)
 }
 
 export function json<T = any>(
   options: Partial<LowDBServiceOptions<T>> = {}
 ) {
   const filename =
-      options.filename ||
-      genTempName() + '.json'
+    options.filename ||
+    genTempName() + '.json'
   return new JSONFile(filename)
 }
 
@@ -94,6 +93,7 @@ export class LowDBAdapter<
   store: Adapter<Record<string, any>>
   _uId: number
   filename: string // Probably unnecesary
+  defaultModel: Low<Record<string, any>>
   db: Low<Record<string, any>>
   partition: string
   data: Record<string, any>
@@ -104,29 +104,33 @@ export class LowDBAdapter<
       id: 'id',
       matcher: sift.default,
       sorter,
-      // store: {},
       startId: 0,
       ...options,
     })
     this._uId = this.options.startId
-    this.store = this.options.Model || yaml(options)
-    this.db = new Low(this.store)
+    this.defaultModel = this.options.Model || new Low(yaml(options))
     this.partition = options.partition
     this.waitForDisk = !!(options.waitForDisk || this.partition)
   }
 
-  async load() {
-    if (this.db.data === null) {
-      await this.db.read()
-      this.db.data ||= {}
-      if (this.db.data['' + (this._uId + 1)]) {
-        this._uId = Object.keys(this.db.data).length + this._uId
+  async getModel(params: any) {
+    let model = this.defaultModel
+    if (params.adapter?.Model) {
+      model = params.adapter.Model
+    }
+    if (model.data === null) {
+      await model.read()
+      model.data ||= {}
+      if (model.data['' + (this._uId + 1)]) {
+        this._uId = Object.keys(model.data).length + this._uId
       }
     }
-    if (this.partition && this.db.data[this.partition] === undefined) {
-      this.db.data[this.partition] = {}
+    if (this.partition && model.data[this.partition] === undefined) {
+      model.data[this.partition] = {}
     }
-    this.data = this.partition ? this.db.data[this.partition] : this.db.data
+    this.data = this.partition ? model.data[this.partition] : model.data
+
+    return model
   }
 
   async getEntries(_params?: ServiceParams) {
@@ -155,7 +159,7 @@ export class LowDBAdapter<
   async _find(
     params: ServiceParams = {} as ServiceParams
   ): Promise<Paginated<Result> | Result[]> {
-    await this.load()
+    await this.getModel(params)
     const { paginate } = this.getOptions(params)
     const { query, filters } = this.getQuery(params)
 
@@ -217,7 +221,7 @@ export class LowDBAdapter<
     id: Id,
     params: ServiceParams = {} as ServiceParams
   ): Promise<Result> {
-    await this.load()
+    await this.getModel(params)
     const { query } = this.getQuery(params)
 
     if (id in this.data) {
@@ -244,7 +248,7 @@ export class LowDBAdapter<
     data: Partial<Data> | Partial<Data>[],
     params: ServiceParams = {} as ServiceParams
   ): Promise<Result | Result[]> {
-    await this.load()
+    const model = await this.getModel(params)
     const createEntry = async (
       data: Partial<Data> | Partial<Data>[],
       params: ServiceParams = {} as ServiceParams
@@ -265,9 +269,9 @@ export class LowDBAdapter<
 
     await result
     if (this.waitForDisk) { // Be safe if fornicating
-      await this.db.write()
+      await model.write()
     } else {
-      this.db.write()
+      model.write()
     }
     return result
   }
@@ -277,7 +281,7 @@ export class LowDBAdapter<
     data: Data,
     params: ServiceParams = {} as ServiceParams
   ): Promise<Result> {
-    await this.load()
+    const model = await this.getModel(params)
     if (id === null || Array.isArray(data)) {
       throw new BadRequest(
         "You can not replace multiple instances. Did you mean 'patch'?"
@@ -295,9 +299,9 @@ export class LowDBAdapter<
     this.data[id] = result
 
     if (this.waitForDisk) {
-      await this.db.write()
+      await model.write()
     } else {
-      this.db.write()
+      model.write()
     }
     return this._get(id, params)
   }
@@ -318,7 +322,7 @@ export class LowDBAdapter<
     data: PatchData,
     params: ServiceParams = {} as ServiceParams
   ): Promise<Result | Result[]> {
-    await this.load()
+    const model = await this.getModel(params)
     if (id === null && !this.allowsMulti('patch', params)) {
       throw new MethodNotAllowed('Can not patch multiple entries')
     }
@@ -348,9 +352,9 @@ export class LowDBAdapter<
 
     await result
     if (this.waitForDisk) {
-      await this.db.write()
+      await model.write()
     } else {
-      this.db.write()
+      model.write()
     }
     return result
   }
@@ -365,7 +369,7 @@ export class LowDBAdapter<
     id: NullableId,
     params: ServiceParams = {} as ServiceParams
   ): Promise<Result | Result[]> {
-    await this.load()
+    const model = await this.getModel(params)
     if (id === null && !this.allowsMulti('remove', params)) {
       throw new MethodNotAllowed('Can not remove multiple entries')
     }
@@ -389,9 +393,9 @@ export class LowDBAdapter<
 
     delete this.data[id]
     if (this.waitForDisk) {
-      await this.db.write()
+      await model.write()
     } else {
-      this.db.write()
+      model.write()
     }
     return entry
   }

test/index.test.ts

@@ -2,8 +2,10 @@ import assert from 'assert'
 import { adapterTests } from '@feathersjs/adapter-tests'
 import errors from '@feathersjs/errors'
 import { feathers } from '@feathersjs/feathers'
-
-import { LowDBService } from '../src/index.js'
+// @ts-ignore
+import { LowDBService, YAMLFile } from '../src/index.js'
+// @ts-ignore
+import { Low } from 'lowdb'
 
 const testSuite = adapterTests([
   '.options',
@@ -177,6 +179,7 @@ describe('Feathers Memory Service', () => {
     assert.ok(matcherCalled, 'matcher called')
   })
 
+
   it('does not modify the original data', async () => {
     const people = app.service('people')
 
@@ -194,6 +197,31 @@ describe('Feathers Memory Service', () => {
     await people.remove(person.id)
   })
 
+  it('support params.adapter.Model', async () => {
+    const Model = new Low(new YAMLFile('/tmp/test-model-' + Date.now() + '.yml'))
+    const oldParams = { adapter: { Model } } as any
+    const people = app.service('people')
+
+    const youngPerson = await people.create({
+      id: 42,
+      name: 'Delete tester',
+      age: 19,
+    })
+    const oldPerson = await people.create({
+      id: 42,
+      name: 'Delete tester',
+      age: 69,
+    }, oldParams)
+    const youngPersonRes = await people.get(42)
+    const oldPersonRes = await people.get(42, oldParams)
+    assert.strictEqual(youngPerson.age, 19)
+    assert.strictEqual(youngPersonRes.age, 19)
+    assert.strictEqual(oldPerson.age, 69)
+    assert.strictEqual(oldPersonRes.age, 69)
+
+    await people.remove(youngPerson.id)
+  })
+
   it('update with null throws error', async () => {
     try {
       await app.service('people').update(null, {})