Support JIT invoicing on donations to rewards pool (#515)

* Support JIT invoicing on donations to rewards pool

Now you can just-in-time fund your account to donate to SN's reward pool.

You can also donate without an account via the @anon account, also using
JIT invoices.

* Ensure donate amount is numeric

* Explicit error checking for hash being required for invoice validation

* let donation exceptions bubble for jit funding

---------

Co-authored-by: keyan <keyan.kousha+huumn@gmail.com>

api/resolvers/item.js

@@ -38,7 +38,10 @@ export async function commentFilterClause (me, models) {
   return clause
 }
 
-async function checkInvoice (models, hash, hmac, fee) {
+export async function checkInvoice (models, hash, hmac, fee) {
+  if (!hash) {
+    throw new GraphQLError('hash required', { extensions: { code: 'BAD_INPUT' } })
+  }
   if (!hmac) {
     throw new GraphQLError('hmac required', { extensions: { code: 'BAD_INPUT' } })
   }

api/resolvers/rewards.js

@@ -1,8 +1,9 @@
 import { GraphQLError } from 'graphql'
+import { settleHodlInvoice } from 'ln-service'
 import { amountSchema, ssValidate } from '../../lib/validate'
 import serialize from './serial'
 import { ANON_USER_ID } from '../../lib/constants'
-import { getItem } from './item'
+import { getItem, checkInvoice } from './item'
 
 export default {
   Query: {
@@ -102,17 +103,38 @@ export default {
     }
   },
   Mutation: {
-    donateToRewards: async (parent, { sats }, { me, models }) => {
-      if (!me) {
-        throw new GraphQLError('you must be logged in', { extensions: { code: 'UNAUTHENTICATED' } })
+    donateToRewards: async (parent, { sats, hash, hmac }, { me, models, lnd }) => {
+      if (!me && !hash) {
+        throw new GraphQLError('you must be logged in or pay', { extensions: { code: 'FORBIDDEN' } })
+      }
+      let user
+      if (me) {
+        user = me
+      }
+
+      let invoice
+      if (hash) {
+        invoice = await checkInvoice(models, hash, hmac, sats)
+        user = invoice.user
       }
 
       await ssValidate(amountSchema, { amount: sats })
 
-      await serialize(models,
+      const trx = [
         models.$queryRawUnsafe(
           'SELECT donate($1::INTEGER, $2::INTEGER)',
-          sats, Number(me.id)))
+          sats, Number(user.id))
+      ]
+
+      if (invoice) {
+        trx.unshift(models.$queryRaw`UPDATE users SET msats = msats + ${invoice.msatsReceived} WHERE id = ${user.id}`)
+        trx.push(models.invoice.update({ where: { hash: invoice.hash }, data: { confirmedAt: new Date() } }))
+      }
+      await serialize(models, ...trx)
+
+      if (invoice?.isHeld) {
+        await settleHodlInvoice({ secret: invoice.preimage, lnd })
+      }
 
       return sats
     }

api/typeDefs/rewards.js

@@ -7,7 +7,7 @@ export default gql`
   }
 
   extend type Mutation {
-    donateToRewards(sats: Int!): Int!
+    donateToRewards(sats: Int!, hash: String, hmac: String): Int!
   }
 
   type Rewards {

pages/rewards/index.js

@@ -92,8 +92,8 @@ export function DonateButton () {
   const toaster = useToast()
   const [donateToRewards] = useMutation(
     gql`
-      mutation donateToRewards($sats: Int!) {
-        donateToRewards(sats: $sats)
+      mutation donateToRewards($sats: Int!, $hash: String, $hmac: String) {
+        donateToRewards(sats: $sats, hash: $hash, hmac: $hmac)
       }`)
 
   return (
@@ -104,24 +104,28 @@ export function DonateButton () {
             amount: 1000
           }}
           schema={amountSchema}
-          onSubmit={async ({ amount }) => {
-            try {
-              await donateToRewards({
-                variables: {
-                  sats: Number(amount)
-                }
-              })
-              onClose()
-              toaster.success('donated')
-            } catch (err) {
-              console.error(err)
+          invoiceable
+          onSubmit={async ({ amount, hash, hmac }) => {
+            const { error } = await donateToRewards({
+              variables: {
+                sats: Number(amount),
+                hash,
+                hmac
+              }
+            })
+            if (error) {
+              console.error(error)
               toaster.danger('failed to donate')
+            } else {
+              toaster.success('donated')
             }
+            onClose()
           }}
         >
           <Input
             label='amount'
             name='amount'
+            type='number'
             required
             autoFocus
             append={<InputGroup.Text className='text-monospace'>sats</InputGroup.Text>}