feat(api): add get plan by id method

Author: stfsy

lib/paddle/api.js

@@ -163,6 +163,22 @@ module.exports = class {
         }))
     }
 
+    /**
+     * 
+     * @param {String} plan subscription plan id
+     * @returns
+     */
+    async getPlan({ plan_id }) {
+        const form = {
+            vendor_id: this._vendorId,
+            vendor_auth_code: this._authCode,
+            plan: plan_id
+        }
+        return this._returnResponseIf200(this._request(this._vendorsBaseUrl + PATH_LIST_PLANS, {
+            form
+        }))
+    }
+
     /**
      * 
      * @returns 

test-e2e/spec/api.spec.js

@@ -29,6 +29,11 @@ test('list all plans', async () => {
     expect(subs.length).toBeGreaterThanOrEqual(2)
 })
 
+test('get plan by id', async () => {
+    const subs = await api.getPlan({ plan_id: 33590 })
+    expect(subs.length).toEqual(1)
+})
+
 test('list one plan', async () => {
     const subs = await api.listPlans(33590)
     expect(subs).toHaveLength(1)