Send emails for new comments on markets you commented on or created.

common/user.ts

@@ -28,6 +28,7 @@ export type PrivateUser = {
 
   email?: string
   unsubscribedFromResolutionEmails?: boolean
+  unsubscribedFromCommentEmails?: boolean
   initialDeviceToken?: string
   initialIpAddress?: string
 }

functions/src/emails.ts

@@ -1,11 +1,12 @@
 import _ = require('lodash')
 import { getProbability } from '../../common/calculate'
+import { Comment } from '../../common/comment'
 import { Contract } from '../../common/contract'
 import { CREATOR_FEE } from '../../common/fees'
 import { PrivateUser, User } from '../../common/user'
 import { formatMoney, formatPercent } from '../../common/util/format'
 import { sendTemplateEmail, sendTextEmail } from './send-email'
-import { getPrivateUser, getUser } from './utils'
+import { getPrivateUser, getUser, isProd } from './utils'
 
 type market_resolved_template = {
   userId: string
@@ -138,3 +139,48 @@ export const sendMarketCloseEmail = async (
     }
   )
 }
+
+export const sendNewCommentEmail = async (
+  userId: string,
+  commentCreator: User,
+  comment: Comment,
+  contract: Contract
+) => {
+  const privateUser = await getPrivateUser(userId)
+  if (
+    !privateUser ||
+    privateUser.unsubscribedFromCommentEmails ||
+    !privateUser.email
+  )
+    return
+
+  const user = await getUser(userId)
+  if (!user) return
+
+  const { question, creatorUsername, slug } = contract
+  const marketUrl = `https://manifold.markets/${creatorUsername}/${slug}`
+
+  const unsubscribeUrl = `https://us-central1-${
+    isProd ? 'mantic-markets' : 'dev-mantic-markets'
+  }.cloudfunctions.net/unsubscribe?id=${userId}&type=market-comment`
+
+  const { name: commentorName, avatarUrl: commentorAvatarUrl } = commentCreator
+  const { text } = comment
+
+  const subject = `Comment on ${question}`
+  const from = `${commentorName} <info@manifold.markets>`
+
+  await sendTemplateEmail(
+    privateUser.email,
+    subject,
+    'market-comment',
+    {
+      commentorName,
+      commentorAvatarUrl: commentorAvatarUrl ?? '',
+      comment: text,
+      marketUrl,
+      unsubscribeUrl,
+    },
+    { from }
+  )
+}

functions/src/index.ts

@@ -12,6 +12,7 @@ export * from './create-contract'
 export * from './create-user'
 export * from './create-fold'
 export * from './create-answer'
+export * from './on-create-comment'
 export * from './on-fold-follow'
 export * from './on-fold-delete'
 export * from './unsubscribe'

functions/src/on-create-comment.ts

@@ -0,0 +1,40 @@
+import * as functions from 'firebase-functions'
+import * as admin from 'firebase-admin'
+import * as _ from 'lodash'
+
+import { getContract, getUser, getValues } from './utils'
+import { Comment } from '../../common/comment'
+import { sendNewCommentEmail } from './emails'
+
+const firestore = admin.firestore()
+
+export const onCreateComment = functions.firestore
+  .document('contracts/{contractId}/comments/{commentId}')
+  .onCreate(async (change, context) => {
+    const { contractId } = context.params as {
+      contractId: string
+    }
+
+    const contract = await getContract(contractId)
+    if (!contract) return
+
+    const comment = change.data() as Comment
+
+    const commentCreator = await getUser(comment.userId)
+    if (!commentCreator) return
+
+    const comments = await getValues<Comment>(
+      firestore.collection('contracts').doc(contractId).collection('comments')
+    )
+
+    const recipientUserIds = _.uniq([
+      contract.creatorId,
+      ...comments.map((comment) => comment.userId),
+    ]).filter((id) => id !== comment.userId)
+
+    await Promise.all(
+      recipientUserIds.map((userId) =>
+        sendNewCommentEmail(userId, commentCreator, comment, contract)
+      )
+    )
+  })

functions/src/send-email.ts

@@ -24,10 +24,11 @@ export const sendTemplateEmail = (
   to: string,
   subject: string,
   templateId: string,
-  templateData: Record<string, string>
+  templateData: Record<string, string>,
+  options?: { from: string }
 ) => {
   const data = {
-    from: 'Manifold Markets <info@manifold.markets>',
+    from: options?.from ?? 'Manifold Markets <info@manifold.markets>',
     to,
     subject,
     template: templateId,

functions/src/stripe.ts

@@ -2,7 +2,7 @@ import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
 import Stripe from 'stripe'
 
-import { payUser } from './utils'
+import { isProd, payUser } from './utils'
 
 export type StripeTransaction = {
   userId: string
@@ -18,8 +18,7 @@ const stripe = new Stripe(functions.config().stripe.apikey, {
 })
 
 // manage at https://dashboard.stripe.com/test/products?active=true
-const manticDollarStripePrice =
-  admin.instanceId().app.options.projectId === 'mantic-markets'
+const manticDollarStripePrice = isProd
   ? {
       500: 'price_1KFQXcGdoFKoCJW770gTNBrm',
       1000: 'price_1KFQp1GdoFKoCJW7Iu0dsF65',

functions/src/unsubscribe.ts

@@ -1,30 +1,36 @@
 import * as functions from 'firebase-functions'
 import * as admin from 'firebase-admin'
 import * as _ from 'lodash'
-import { getPrivateUser } from './utils'
+import { getUser } from './utils'
 import { PrivateUser } from '../../common/user'
 
 export const unsubscribe = functions
   .runWith({ minInstances: 1 })
   .https.onRequest(async (req, res) => {
-    let id = req.query.id as string
-    if (!id) return
+    const { id, type } = req.query as { id: string; type: string }
+    if (!id || !type) return
 
-    let privateUser = await getPrivateUser(id)
+    const user = await getUser(id)
 
-    if (privateUser) {
-      let { username } = privateUser
+    if (user) {
+      const { name } = user
 
       const update: Partial<PrivateUser> = {
-        unsubscribedFromResolutionEmails: true,
+        unsubscribedFromResolutionEmails: type === 'market-resolve',
+        unsubscribedFromCommentEmails: type === 'market-comment',
       }
 
       await firestore.collection('private-users').doc(id).update(update)
 
+      if (type === 'market-resolve')
         res.send(
-        username +
-          ', you have been unsubscribed from market resolution emails on Manifold Markets.'
+          `${name}, you have been unsubscribed from market resolution emails on Manifold Markets.`
         )
+      else if (type === 'market-comment')
+        res.send(
+          `${name}, you have been unsubscribed from market comment emails on Manifold Markets.`
+        )
+      else res.send(`${name}, you have been unsubscribed.`)
     } else {
       res.send('This user is not currently subscribed or does not exist.')
     }

functions/src/utils.ts

@@ -3,6 +3,9 @@ import * as admin from 'firebase-admin'
 import { Contract } from '../../common/contract'
 import { PrivateUser, User } from '../../common/user'
 
+export const isProd =
+  admin.instanceId().app.options.projectId === 'mantic-markets'
+
 export const getValue = async <T>(collection: string, doc: string) => {
   const snap = await admin.firestore().collection(collection).doc(doc).get()