From c132ac43b9f5dc6999707d92a1b93183a45b9b2e Mon Sep 17 00:00:00 2001
From: mike12345567 <me@michaeldrury.co.uk>
Date: Thu, 30 Sep 2021 12:17:27 +0100
Subject: [PATCH] Adding cloud -> self host and self host -> cloud view
 migrations.

---
 .../src/api/controllers/row/internal.js       | 47 +++++++++----------
 .../server/src/api/controllers/view/utils.js  | 27 +++++++++++
 2 files changed, 48 insertions(+), 26 deletions(-)

diff --git a/packages/server/src/api/controllers/row/internal.js b/packages/server/src/api/controllers/row/internal.js
index d429c14cc7..43ee3dd235 100644
--- a/packages/server/src/api/controllers/row/internal.js
+++ b/packages/server/src/api/controllers/row/internal.js
@@ -5,7 +5,6 @@ const {
   generateRowID,
   DocumentTypes,
   InternalTables,
-  generateMemoryViewID,
 } = require("../../../db/utils")
 const userController = require("../user")
 const {
@@ -20,7 +19,12 @@ const { fullSearch, paginatedSearch } = require("./internalSearch")
 const { getGlobalUsersFromMetadata } = require("../../../utilities/global")
 const inMemoryViews = require("../../../db/inMemoryView")
 const env = require("../../../environment")
-const { migrateToInMemoryView } = require("../view/utils")
+const {
+  migrateToInMemoryView,
+  migrateToDesignView,
+  getFromDesignDoc,
+  getFromMemoryDoc,
+} = require("../view/utils")
 
 const CALCULATION_TYPES = {
   SUM: "sum",
@@ -74,33 +78,24 @@ async function getRawTableData(ctx, db, tableId) {
 }
 
 async function getView(db, viewName) {
-  let viewInfo
-  async function getFromDesignDoc() {
-    const designDoc = await db.get("_design/database")
-    viewInfo = designDoc.views[viewName]
-    return viewInfo
-  }
-  let migrate = false
-  if (env.SELF_HOSTED) {
-    viewInfo = await getFromDesignDoc()
-  } else {
-    try {
-      viewInfo = await db.get(generateMemoryViewID(viewName))
-      if (viewInfo) {
-        viewInfo = viewInfo.view
-      }
-    } catch (err) {
-      // check if it can be retrieved from design doc (needs migrated)
-      if (err.status !== 404) {
-        viewInfo = null
-      } else {
-        viewInfo = await getFromDesignDoc()
-        migrate = !!viewInfo
-      }
+  let mainGetter = env.SELF_HOSTED ? getFromDesignDoc : getFromMemoryDoc
+  let secondaryGetter = env.SELF_HOSTED ? getFromMemoryDoc : getFromDesignDoc
+  let migration = env.SELF_HOSTED ? migrateToDesignView : migrateToInMemoryView
+  let viewInfo,
+    migrate = false
+  try {
+    viewInfo = await mainGetter(db, viewName)
+  } catch (err) {
+    // check if it can be retrieved from design doc (needs migrated)
+    if (err.status !== 404) {
+      viewInfo = null
+    } else {
+      viewInfo = await secondaryGetter(db, viewName)
+      migrate = !!viewInfo
     }
   }
   if (migrate) {
-    await migrateToInMemoryView(db, viewName)
+    await migration(db, viewName)
   }
   if (!viewInfo) {
     throw "View does not exist."
diff --git a/packages/server/src/api/controllers/view/utils.js b/packages/server/src/api/controllers/view/utils.js
index c93604177f..1f3b980882 100644
--- a/packages/server/src/api/controllers/view/utils.js
+++ b/packages/server/src/api/controllers/view/utils.js
@@ -107,3 +107,30 @@ exports.migrateToInMemoryView = async (db, viewName) => {
   await db.put(designDoc)
   await exports.saveView(db, null, viewName, view)
 }
+
+exports.migrateToDesignView = async (db, viewName) => {
+  let view = await db.get(generateMemoryViewID(viewName))
+  const designDoc = await db.get("_design/database")
+  designDoc.views[viewName] = view.view
+  await db.put(designDoc)
+  await db.remove(view._id, view._rev)
+}
+
+exports.getFromDesignDoc = async (db, viewName) => {
+  const designDoc = await db.get("_design/database")
+  let view = designDoc.views[viewName]
+  if (view == null) {
+    throw { status: 404, message: "Unable to get view" }
+  }
+  return view
+}
+
+exports.getFromMemoryDoc = async (db, viewName) => {
+  let view = await db.get(generateMemoryViewID(viewName))
+  if (view) {
+    view = view.view
+  } else {
+    throw { status: 404, message: "Unable to get view" }
+  }
+  return view
+}