Merge pull request #93 from shocknet/feat/feed

Feat/feed

package.json

@@ -41,6 +41,7 @@
     "lodash": "^4.17.15",
     "method-override": "^2.3.7",
     "promise": "^8.0.1",
+    "ramda": "^0.27.0",
     "request": "^2.87.0",
     "request-promise": "^4.2.2",
     "response-time": "^2.3.2",
@@ -61,6 +62,7 @@
     "@types/jest": "^24.0.18",
     "@types/jsonwebtoken": "^8.3.7",
     "@types/lodash": "^4.14.141",
+    "@types/ramda": "types/npm-ramda#dist",
     "@types/socket.io": "^2.1.4",
     "@types/uuid": "^3.4.5",
     "babel-eslint": "^10.0.3",

services/gunDB/contact-api/getters/feed.js

@@ -0,0 +1,79 @@
+/**
+ * @format
+ */
+const Common = require('shock-common')
+const isFinite = require('lodash/isFinite')
+const shuffle = require('lodash/shuffle')
+const R = require('ramda')
+
+const Follows = require('./follows')
+const Wall = require('./wall')
+
+/**
+ * @param {number} numberOfPublicKeyGroups
+ * @param {number} pageRequested
+ * @returns {[ number , number ]}
+ */
+const calculateFeedPage = (numberOfPublicKeyGroups, pageRequested) => {
+  // thanks to sebassdc
+
+  return [
+    (pageRequested - 1) % numberOfPublicKeyGroups,
+    Math.ceil(pageRequested / numberOfPublicKeyGroups)
+  ]
+}
+
+/**
+ * @param {number} page
+ * @throws {TypeError}
+ * @throws {RangeError}
+ * @returns {Promise<Common.SchemaTypes.Post[]>}
+ */
+const getFeedPage = async page => {
+  if (!isFinite(page)) {
+    throw new TypeError(`Please provide an actual number for [page]`)
+  }
+
+  if (page <= 0) {
+    throw new RangeError(`Please provide only positive numbers for [page]`)
+  }
+
+  const subbedPublicKeys = Object.values(await Follows.currentFollows()).map(
+    f => f.user
+  )
+
+  if (subbedPublicKeys.length === 0) {
+    return []
+  }
+
+  // say there are 20 public keys total
+  // page 1: page 1 from first 10 public keys
+  // page 2: page 1 from second 10 public keys
+  // page 3: page 2 from first 10 public keys
+  // page 4: page 2 from first 10 public keys
+  // etc
+  // thanks to sebassdc (github)
+
+  const pagedPublicKeys = R.splitEvery(10, shuffle(subbedPublicKeys))
+
+  const [publicKeyGroupIdx, pageToRequest] = calculateFeedPage(
+    pagedPublicKeys.length,
+    page
+  )
+
+  const publicKeys = pagedPublicKeys[publicKeyGroupIdx]
+
+  const fetchedPages = await Promise.all(
+    publicKeys.map(pk => Wall.getWallPage(pageToRequest, pk))
+  )
+
+  const fetchedPostsGroups = fetchedPages.map(wp => Object.values(wp.posts))
+  const fetchedPosts = R.flatten(fetchedPostsGroups)
+  const sortered = R.sort((a, b) => b.date - a.date, fetchedPosts)
+
+  return sortered
+}
+
+module.exports = {
+  getFeedPage
+}

services/gunDB/contact-api/getters/index.js

@@ -7,6 +7,7 @@ const Key = require('../key')
 const Utils = require('../utils')
 
 const Wall = require('./wall')
+const Feed = require('./feed')
 const User = require('./user')
 
 /**
@@ -96,4 +97,5 @@ module.exports.Follows = require('./follows')
 module.exports.getWallPage = Wall.getWallPage
 module.exports.getWallTotalPages = Wall.getWallTotalPages
 
-module.exports.getUser = User.getAnUser
+module.exports.getFeedPage = Feed.getFeedPage
+module.exports.getAnUser = User.getAnUser

services/gunDB/contact-api/getters/wall.js

@@ -9,15 +9,19 @@ const Key = require('../key')
 const Wall = require('./user')
 
 /**
+ * @param {string=} publicKey
  * @returns {Promise<number>}
  */
-const getWallTotalPages = async () => {
+const getWallTotalPages = async publicKey => {
   const totalPages = await Utils.tryAndWait(
-    (_, user) =>
-      user
+    (gun, u) => {
+      const user = publicKey ? gun.get(`~${publicKey}`) : u
+
+      return user
         .get(Key.WALL)
         .get(Key.NUM_OF_PAGES)
-        .then(),
+        .then()
+    },
     v => typeof v !== 'number'
   )
 
@@ -26,12 +30,13 @@ const getWallTotalPages = async () => {
 
 /**
  * @param {number} page
+ * @param {string=} publicKey
  * @throws {TypeError}
  * @throws {RangeError}
  * @returns {Promise<Common.SchemaTypes.WallPage>}
  */
-const getWallPage = async page => {
-  const totalPages = await getWallTotalPages()
+const getWallPage = async (page, publicKey) => {
+  const totalPages = await getWallTotalPages(publicKey)
 
   if (page === 0 || totalPages === 0) {
     return {
@@ -50,15 +55,18 @@ const getWallPage = async page => {
    * @type {Common.SchemaTypes.WallPage}
    */
   const thePage = await Utils.tryAndWait(
-    (_, user) =>
-      new Promise(res => {
+    (g, u) => {
+      const user = publicKey ? g.get(`~${publicKey}`) : u
+
+      return new Promise(res => {
         user
           .get(Key.WALL)
           .get(Key.PAGES)
           .get(actualPageIdx.toString())
           // @ts-ignore
           .load(res)
-      }),
+      })
+    },
     maybePage => {
       if (typeof maybePage !== 'object' || maybePage === null) {
         return true
@@ -97,9 +105,13 @@ const getWallPage = async page => {
     // delete unsuccessful writes
     if (post === null) {
       delete clean.posts[key]
+      clean.count--
     } else {
-      // eslint-disable-next-line no-await-in-loop
-      post.author = await Wall.getMyUser()
+      post.author = publicKey
+        ? // eslint-disable-next-line no-await-in-loop
+          await Wall.getAnUser(publicKey)
+        : // eslint-disable-next-line no-await-in-loop
+          await Wall.getMyUser()
       post.id = key
     }
   }

src/routes.js

@@ -1842,9 +1842,10 @@ module.exports = async (
   })
 ////////////////////////////////////////////////////////////////////////////////
 
-  app.get(`/api/gun/wall`, async (req, res) => {
+  app.get(`/api/gun/wall/:publicKey?`, async (req, res) => {
     try {
       const { page } = req.query;
+      const {publicKey} = req.params
 
       const pageNum = Number(page)
 
@@ -1855,8 +1856,8 @@ module.exports = async (
         })
       }
 
-      const totalPages = await GunGetters.getWallTotalPages()
-      const fetchedPage = await GunGetters.getWallPage(pageNum)
+      const totalPages = await GunGetters.getWallTotalPages(publicKey)
+      const fetchedPage = await GunGetters.getWallPage(pageNum, publicKey)
 
       return res.status(200).json({
         ...fetchedPage,
@@ -1969,6 +1970,40 @@ module.exports = async (
   ap.put(`/api/gun/follows/:publicKey`,apiGunFollowsPut)
   ap.delete(`/api/gun/follows/:publicKey`, apiGunFollowsDelete)
 
+  /**
+    * @type {RequestHandler<{}>}
+    */
+   const apiGunFeedGet = async (req, res) => {
+    try {
+      const { page: pageStr } = req.query;
+      const page = Number(pageStr)
+
+      if (!isARealUsableNumber(page)) {
+        return res.status(400).json({
+          field: 'page',
+          errorMessage: 'page must be a number'
+        })
+      }
+
+      if (page < 1) {
+        return res.status(400).json({
+          field: page,
+          errorMessage: 'page must be a positive number'
+        })
+      }
+
+      return res.status(200).json({
+        posts: await GunGetters.getFeedPage(page)
+      })
+    } catch (err) {
+      return res.status(500).json({
+        errorMessage: err.message || 'Unknown error inside /api/gun/follows/'
+      })
+    }
+  }
+
+  ap.get(`/api/gun/feed`, apiGunFeedGet)
+
   /**
    * Return app so that it can be used by express.
    */

yarn.lock

@@ -633,6 +633,10 @@
   resolved "https://registry.yarnpkg.com/@types/parse-json/-/parse-json-4.0.0.tgz#2f8bb441434d163b35fb8ffdccd7138927ffb8c0"
   integrity sha512-//oorEZjL6sbPcKUaCdIGlIUeH26mgzimjBB77G6XRgnDl/L5wOnpyBGRe/Mmf5CVW3PwEBE1NjiMZ/ssFh4wA==
 
+"@types/ramda@types/npm-ramda#dist":
+  version "0.25.0"
+  resolved "https://codeload.github.com/types/npm-ramda/tar.gz/9529aa3c8ff70ff84afcbc0be83443c00f30ea90"
+
 "@types/range-parser@*":
   version "1.2.3"
   resolved "https://registry.yarnpkg.com/@types/range-parser/-/range-parser-1.2.3.tgz#7ee330ba7caafb98090bece86a5ee44115904c2c"
@@ -5388,6 +5392,11 @@ ramda@^0.26.1:
   resolved "https://registry.yarnpkg.com/ramda/-/ramda-0.26.1.tgz#8d41351eb8111c55353617fc3bbffad8e4d35d06"
   integrity sha512-hLWjpy7EnsDBb0p+Z3B7rPi3GDeRG5ZtiI33kJhTt+ORCd38AbAIjB/9zRIUoeTbE/AVX5ZkU7m6bznsvrf8eQ==
 
+ramda@^0.27.0:
+  version "0.27.0"
+  resolved "https://registry.yarnpkg.com/ramda/-/ramda-0.27.0.tgz#915dc29865c0800bf3f69b8fd6c279898b59de43"
+  integrity sha512-pVzZdDpWwWqEVVLshWUHjNwuVP7SfcmPraYuqocJp1yo2U1R7P+5QAfDhdItkuoGqIBnBYrtPp7rEPqDn9HlZA==
+
 random-bytes@~1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/random-bytes/-/random-bytes-1.0.0.tgz#4f68a1dc0ae58bd3fb95848c30324db75d64360b"