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<!--
Any copyright is dedicated to the Public Domain.
http://creativecommons.org/publicdomain/zero/1.0/
-->
<html>
<head>
<title>Indexed Database Test</title>
<script type="text/javascript">
function report(result) {
var message = { source: "iframe" };
message.result = result;
window.parent.postMessage(message, "*");
}
function runIndexedDBTest() {
var db = null;
// Create the data-store
function createDatastore() {
try {
var request = indexedDB.open(window.location.pathname, 1);
request.onupgradeneeded = function(event) {
event.target.result.createObjectStore("foo");
};
request.onsuccess = function(event) {
db = event.target.result;
createAndStoreBlob();
};
}
catch (e) {
dump("EXCEPTION IN CREATION: " + e + "\n " + e.stack + "\n");
report(false);
}
}
function createAndStoreBlob() {
const BLOB_DATA = ["fun ", "times ", "all ", "around!"];
var blob = new Blob(BLOB_DATA, { type: "text/plain" });
var objectStore = db.transaction("foo", "readwrite").objectStore("foo");
objectStore.add({ blob }, 42).onsuccess = refetchBlob;
}
function refetchBlob() {
var foo = db.transaction("foo").objectStore("foo");
foo.get(42).onsuccess = fetchedBlobCreateWorkerAndSendBlob;
}
function fetchedBlobCreateWorkerAndSendBlob(event) {
var idbBlob = event.target.result.blob;
var compositeBlob = new Blob(["I like the following blob: ", idbBlob],
{ type: "text/fancy" });
function workerScript() {
/* eslint-env worker */
onmessage = function(event) {
// Save the Blob to the worker's global scope.
self.holdOntoBlob = event.data;
// Send any message so we can serialize and keep our runtime behaviour
// consistent.
postMessage("kung fu death grip established");
};
}
var url =
URL.createObjectURL(new Blob(["(", workerScript.toString(), ")()"]));
// Keep a reference to the worker on the window.
var worker = window.worker = new Worker(url);
worker.postMessage(compositeBlob);
worker.onmessage = workerLatchedBlobDeleteFromDB;
}
function workerLatchedBlobDeleteFromDB() {
// Delete the reference to the Blob from the database leaving the worker
// thread reference as the only live reference once a GC has cleaned
// out our references that we sent to the worker. The page that owns
// us triggers a GC just for that reason.
var objectStore = db.transaction("foo", "readwrite").objectStore("foo");
objectStore.delete(42).onsuccess = closeDBTellOwningThread;
}
function closeDBTellOwningThread(event) {
// Now that worker has latched the blob, clean up the database.
db.close();
db = null;
report("ready");
}
createDatastore();
}
</script>
</head>
<body onload="runIndexedDBTest();">
</body>
</html>
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