From b9a66d44241f2896ef184511287fb4984671e16d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gustavo=20Andr=C3=A9=20Lelis?= <galelis@gmail.com>
Date: Wed, 15 Jan 2020 11:15:10 -0300
Subject: [PATCH] =?UTF-8?q?fix:=20=F0=9F=90=9B=20Metadata=20is=20being=20m?=
 =?UTF-8?q?istakenly=20purged=20(#1360)?=
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Closes: #1326
---
 .../ViewerRetrieveStudyData.js                    | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/platform/viewer/src/connectedComponents/ViewerRetrieveStudyData.js b/platform/viewer/src/connectedComponents/ViewerRetrieveStudyData.js
index b18ca1fa8..066357192 100644
--- a/platform/viewer/src/connectedComponents/ViewerRetrieveStudyData.js
+++ b/platform/viewer/src/connectedComponents/ViewerRetrieveStudyData.js
@@ -1,5 +1,6 @@
 import React, { useState, useEffect, useContext } from 'react';
 import { metadata, studies, utils, log } from '@ohif/core';
+import usePrevious from '../customHooks/usePrevious';
 
 import ConnectedViewer from './ConnectedViewer.js';
 import PropTypes from 'prop-types';
@@ -128,9 +129,9 @@ const _addSeriesToStudy = (studyMetadata, series) => {
 const _updateMetaDataManager = (study, studyMetadata, series) => {
   updateMetaDataManager(study, series);
 
-  const { studyInstanceUID } = study;
+  const { studyInstanceUid } = study;
 
-  if (!studyMetadataManager.get(studyInstanceUID)) {
+  if (!studyMetadataManager.get(studyInstanceUid)) {
     studyMetadataManager.add(studyMetadata);
   }
 };
@@ -314,9 +315,15 @@ function ViewerRetrieveStudyData({
     }
   };
 
+  const prevStudyInstanceUids = usePrevious(studyInstanceUids);
+
   useEffect(() => {
-    studyMetadataManager.purge();
-    purgeCancellablePromises();
+    const hasStudyInstanceUidsChanged = !(prevStudyInstanceUids && prevStudyInstanceUids.every(e => studyInstanceUids.includes(e)));
+
+    if (hasStudyInstanceUidsChanged) {
+      studyMetadataManager.purge();
+      purgeCancellablePromises();
+    }
   }, [studyInstanceUids]);
 
   useEffect(() => {