76 lines
1.9 KiB
HTML
76 lines
1.9 KiB
HTML
<!doctype html>
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<meta charset="utf-8">
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<script>
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const dbName = "users";
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// Create the database at v1 and detect success via `onsuccess`.
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function createDatabase() {
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return new Promise((resolve, reject) => {
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var dbRequest = window.indexedDB.open(dbName, 1);
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dbRequest.onblocked = () => reject();
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dbRequest.onerror = () => reject();
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dbRequest.onsuccess = (e) => {
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e.target.result.close();
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resolve();
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}
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});
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}
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// Open the database at v2 and detect existance via `onupgradeneeded`.
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function doesDatabaseExist() {
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let didExist = false;
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return new Promise((resolve, reject) => {
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var dbRequest = window.indexedDB.open(dbName, 2);
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dbRequest.onblocked = () => reject();
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dbRequest.onerror = () => reject();
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dbRequest.onsuccess = (e) => {
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e.target.result.close();
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deleteDatabase().then(() => resolve(didExist));
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};
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dbRequest.onupgradeneeded = (e) => {
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didExist = e.oldVersion != 0;
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};
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});
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}
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// Delete the database and detect success via `onsuccess`.
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function deleteDatabase() {
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return new Promise((resolve, reject) => {
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var dbRequest = window.indexedDB.deleteDatabase(dbName);
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dbRequest.onblocked = () => reject();
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dbRequest.onerror = () => reject();
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dbRequest.onsuccess = () => resolve();
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});
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}
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// Step 2
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window.addEventListener("load", () => {
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parent.postMessage(
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{message: "iframe loaded"},
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"*",
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);
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});
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window.addEventListener("message", (e) => {
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if (e.data.message == "create database") {
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// Step 4
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createDatabase().then(() => {
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parent.postMessage(
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{message: "database created"},
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"*",
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);
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});
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} else if (e.data.message == "check database") {
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// Step 6
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doesDatabaseExist().then((result) => {
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parent.postMessage(
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{
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message: "database checked",
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doesDatabaseExist: result,
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},
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"*",
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);
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});
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}
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});
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</script>
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