useage limits on OpenAI requests. closes #12

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## Version 1.3.0
+- Add an example of usage limits (Notes AI Gen).
+- Includes non-destructive schema changes
+```npx prisma db push```
+
 ## Version 1.2.0
 - 'Lift' auth context into server middleware to support authenticated api (rest) endpoints for alternate clients while still supporting fully typed Trpc context.
 

README.md

@@ -85,6 +85,7 @@ Discord [here](https://discord.gg/3hWPDTA4kD)
 - [x] Max Notes enforced
 - [x] Add, Delete notes on Dashboard
 - [x] AI Note generation with OpenAI
+- [x] Per Account, Per Month Useage Limits on AI Access
 
 ### Testing
 - [x] Manual test scenario for auth and sub workflows passing

lib/services/account.service.ts

@@ -2,6 +2,10 @@ import { ACCOUNT_ACCESS } from '~~/prisma/account-access-enum';
 import prisma_client from '~~/prisma/prisma.client';
 import { accountWithMembers, AccountWithMembers, membershipWithAccount, MembershipWithAccount, membershipWithUser, MembershipWithUser } from './service.types';
 import generator from 'generate-password-ts';
+import { UtilService } from './util.service';
+import { AccountLimitError } from './errors';
+
+const config = useRuntimeConfig();
 
 export default class AccountService {
   async getAccountById(account_id: number): Promise<AccountWithMembers> {
@@ -50,6 +54,7 @@ export default class AccountService {
         data: {
           stripe_subscription_id,
           current_period_ends,
+          ai_gen_count:0,
         }
       });
     } else {
@@ -64,6 +69,8 @@ export default class AccountService {
           max_notes: paid_plan.max_notes,
           max_members: paid_plan.max_members,
           plan_name: paid_plan.name,
+          ai_gen_max_pm: paid_plan.ai_gen_max_pm,
+          ai_gen_count:0, // I did vacillate on this point ultimately easier to just reset, discussion here https://www.reddit.com/r/SaaS/comments/16e9bew/should_i_reset_usage_counts_on_plan_upgrade/
         }
       });
     }
@@ -272,4 +279,63 @@ export default class AccountService {
       }
     });
   }
+
+  /*
+  **** Usage Limit Checking *****
+  This is trickier than you might think at first.  Free plan users don't get a webhook from Stripe
+  that we can use to tick over their period end date and associated usage counts.  I also didn't 
+  want to require an additional background thread to do the rollover processing.
+
+  getAccountWithPeriodRollover: retrieves an account record and does the rollover checking returning up to date account info
+  checkAIGenCount: retrieves the account using getAccountWithPeriodRollover, checks the count and returns the account
+  incrementAIGenCount: increments the counter using the account.  Note that passing in the account avoids another db fetch for the account.
+  
+  Note.. for each usage limit, you will need another pair of check/increment methods and of course the count and max limit in the account schema
+
+  How to use in a service method....
+  async someServiceMethod(account_id: number, .....etc) {
+    const accountService = new AccountService();
+    const account = await accountService.checkAIGenCount(account_id);
+    ... User is under the limit so do work
+    await accountService.incrementAIGenCount(account);
+  }
+  */
+
+  async getAccountWithPeriodRollover (account_id: number){
+    const account = await prisma_client.account.findFirstOrThrow({ 
+      where: { id: account_id }
+    });
+
+    if(account.plan_name === config.initialPlanName && account.current_period_ends < new Date()){
+      return await prisma_client.account.update({
+        where: { id: account.id },
+        data: {
+          current_period_ends: UtilService.addMonths(account.current_period_ends,1),
+          // reset anything that is affected by the rollover
+          ai_gen_count: 0,
+        },
+      });
+    };
+
+    return account;
+  }
+  
+  async checkAIGenCount(account_id: number){
+    const account = await this.getAccountWithPeriodRollover(account_id);
+    
+    if(account.ai_gen_count >= account.ai_gen_max_pm){
+      throw new AccountLimitError('Monthly AI gen limit reached, no new AI Generations can be made');
+    }
+
+    return account;
+  }
+
+  async incrementAIGenCount (account: any){
+    return await prisma_client.account.update({
+      where: { id: account.id },
+      data: {
+        ai_gen_count: account.ai_gen_count + 1,
+      }
+    });
+  }
 }

lib/services/notes.service.ts

@@ -1,6 +1,7 @@
 import prisma_client from '~~/prisma/prisma.client';
 import { openai } from './openai.client';
 import { AccountLimitError } from './errors';
+import AccountService from './account.service';
 
 export default class NotesService {
   async getAllNotes() {
@@ -36,7 +37,10 @@ export default class NotesService {
     return prisma_client.note.delete({ where: { id } });
   }
 
-  async generateAINoteFromPrompt(userPrompt: string) {
+  async generateAINoteFromPrompt(userPrompt: string, account_id: number) {
+    const accountService = new AccountService();
+    const account = await accountService.checkAIGenCount(account_id);
+
     const prompt = `
     Write an interesting short note about ${userPrompt}.  
     Restrict the note to a single paragraph.
@@ -49,6 +53,9 @@ export default class NotesService {
       max_tokens: 1000,
       n: 1,
     });
+
+    await accountService.incrementAIGenCount(account);
+
     return completion.data.choices[0].text;
   }
 }

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "supanuxt-saas",
-  "version": "1.2.0",
+  "version": "1.3.0",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "supanuxt-saas",
-      "version": "1.2.0",
+      "version": "1.3.0",
       "hasInstallScript": true,
       "license": "MIT",
       "dependencies": {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "supanuxt-saas",
-  "version": "1.2.0",
+  "version": "1.3.0",
   "author": {
     "name": "Michael Dausmann",
     "email": "mdausmann@gmail.com",

pages/account.vue

@@ -60,6 +60,11 @@
         <span>{{ activeMembership?.account.max_notes }}</span>
       </div>
 
+      <div class="flex gap-4 items-center">
+        <span class="font-bold w-32">AI Gens for this Month/Max:</span>
+        <span>{{ activeMembership?.account.ai_gen_count }} / {{ activeMembership?.account.ai_gen_max_pm }}</span>
+      </div>
+
       <div class="flex gap-4 items-center">
         <span class="font-bold w-32">Maximum Members:</span>
         <span>{{ activeMembership?.account.max_members }}</span>

prisma/schema.prisma

@@ -56,6 +56,8 @@ model Account {
   stripe_customer_id      String?
   max_members             Int        @default(1)
   join_password           String     @unique
+  ai_gen_max_pm           Int        @default(7)
+  ai_gen_count            Int        @default(0)
 
   @@map("account")
 }
@@ -68,6 +70,7 @@ model Plan {
   max_notes               Int         @default(100)
   stripe_product_id       String?
   max_members             Int        @default(1)
+  ai_gen_max_pm           Int        @default(7)
 
   @@map("plan")
 }

prisma/seed.ts

@@ -9,6 +9,7 @@ async function main() {
       features: ['ADD_NOTES', 'EDIT_NOTES', 'VIEW_NOTES'],
       max_notes: 10,
       max_members: 1,
+      ai_gen_max_pm: 7,
     },
   });
   const individualPlan = await prisma.plan.upsert({
@@ -19,6 +20,7 @@ async function main() {
       features: ['ADD_NOTES', 'EDIT_NOTES', 'VIEW_NOTES', 'SPECIAL_FEATURE'],
       max_notes: 100,
       max_members: 1,
+      ai_gen_max_pm: 50,
       stripe_product_id: 'prod_NQR7vwUulvIeqW'
     },
   });
@@ -30,6 +32,7 @@ async function main() {
       features: ['ADD_NOTES', 'EDIT_NOTES', 'VIEW_NOTES', 'SPECIAL_FEATURE', 'SPECIAL_TEAM_FEATURE'],
       max_notes: 200,
       max_members: 10,
+      ai_gen_max_pm: 500,
       stripe_product_id: 'prod_NQR8IkkdhqBwu2'
     },
   });

server/trpc/routers/notes.router.ts

@@ -42,7 +42,7 @@ export const notesRouter = router({
     .input(z.object({ user_prompt: z.string() }))
     .query(async ({ ctx, input }) => {
       const notesService = new NotesService();
-      const noteText = (ctx.activeAccountId)?await notesService.generateAINoteFromPrompt(input.user_prompt):null; 
+      const noteText = (ctx.activeAccountId)?await notesService.generateAINoteFromPrompt(input.user_prompt, ctx.activeAccountId):null; 
       return {
         noteText
       }