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---
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title: Retrieve Messages Using Store Protocol
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hide_table_of_contents: true
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---
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This guide provides detailed steps to create a Light Node for retrieving and filtering historical messages using the [Store protocol ](/learn/concepts/protocols#store ).
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## Create a light node
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Use the `createLightNode()` function to create a Light Node and interact with the Waku Network:
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```js
import { createLightNode } from "@waku/sdk ";
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// Create and start a Light Node
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const node = await createLightNode({ defaultBootstrap: true });
await node.start();
```
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## Connect to store peers
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Use the `waitForRemotePeer()` function to wait for the node to connect with Store peers:
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```js
import { waitForRemotePeer, Protocols } from "@waku/sdk ";
// Wait for a successful peer connection
await waitForRemotePeer(node, [Protocols.Store]);
```
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## Choose a content topic
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[Choose a content topic ](/learn/concepts/content-topics ) for filtering the messages to retrieve and create a message `decoder` :
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```js
import { createDecoder } from "@waku/sdk ";
// Choose a content topic
const contentTopic = "/store-guide/1/message/proto";
// Create a message decoder
const decoder = createDecoder(contentTopic);
```
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## Retrieve messages
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`@waku/sdk` provides the `queryWithOrderedCallback()` and `queryGenerator()` functions for querying `Store` nodes and retrieving historical or missed messages. The responses from `Store` nodes are paginated and require you to process each page sequentially.
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### `queryWithOrderedCallback`
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The `store.queryWithOrderedCallback()` function provides a straightforward method for querying `Store` nodes and processing messages in chronological order through a callback function. It accepts these parameters:
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- `decoders` : List of `decoders` that specify the `content topic` to query for and their [message decryption ](https://rfc.vac.dev/spec/26/ ) methods.
- `callback` : The callback function for processing the retrieved messages.
- `options` (optional): [Query options ](/guides/js-waku/store-retrieve-messages#store-query-options ) to filter the retrieved messages.
```js
// Create the callback function
const callback = (wakuMessage) => {
// Render the message/payload in your application
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console.log(wakuMessage);
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};
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// Query the Store peer
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await node.store.queryWithOrderedCallback(
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[decoder],
callback,
);
```
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:::info
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The `queryWithOrderedCallback()` function always returns the most recent messages in a page first.
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:::
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### `queryGenerator`
The `store.queryGenerator()` function provides more control and flexibility over processing messages retrieved from `Store` nodes through [Async Generators ](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGenerator ). It accepts these parameters:
- `decoders` : List of `decoders` that specify the `content topic` to query for and their [message decryption ](https://rfc.vac.dev/spec/26/ ) methods.
- `options` (optional): [Query options ](/guides/js-waku/store-retrieve-messages#store-query-options ) to filter the retrieved messages.
```js
// Create the store query
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const storeQuery = node.store.queryGenerator([decoder]);
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// Process the messages
for await (const messagesPromises of storeQuery) {
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// Fulfil the messages promises
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const messages = await Promise.all(messagesPromises
.map(async (p) => {
const msg = await p;
// Render the message/payload in your application
console.log(msg);
})
);
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}
```
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:::info
The `queryGenerator()` function always returns the oldest messages in a page first.
:::
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## Store query options
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### `pageDirection`
The `pageDirection` option specifies the direction in which pages are retrieved:
- `BACKWARD` (default): Most recent page first.
- `FORWARD` : Oldest page first.
```js
import { PageDirection } from "@waku/sdk ";
// Retrieve recent messages first
const queryOptions = {
pageDirection: PageDirection.BACKWARD,
};
// Retrieve oldest messages first
const queryOptions = {
pageDirection: PageDirection.FORWARD,
};
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// Query the Store peer with options
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await node.store.queryWithOrderedCallback([decoder], callback, options);
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const storeQuery = node.store.queryGenerator([decoder, options]);
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```
### `cursor`
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The `cursor` option specifies the starting index for retrieving messages. For example, consider a query that retrieves the first page messages and then continues with the next page:
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```js
import { waku } from "@waku/sdk ";
// Create the callback function
const messages = [];
const callback = (wakuMessage) => {
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messages.push(wakuMessage);
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// Return "true" to stop retrieving pages
// Here, it retrieves only the first page
return true;
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};
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// Retrieve the first page of messages
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// This retrieves all the messages if "return true" is not present
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await node.store.queryWithOrderedCallback(
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[decoder],
callback,
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);
// Create the cursor
const lastMessage = messages[messages.length - 1];
const cursor = await waku.createCursor(lastMessage);
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// Retrieve the next page of messages
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// The message at the cursor index is excluded from the result
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await node.store.queryWithOrderedCallback(
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[decoder],
callback,
{
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cursor: cursor,
},
);
console.log(messages);
```
:::info
If you omit the `cursor` option, the query will start from the beginning or end of the history, depending on the [page direction ](#pagedirection ).
:::
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### `timeFilter`
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The `timeFilter` option specifies a time frame to retrieve messages from. For example, consider a query that retrieves messages from the previous week:
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```js
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// Get the time frame
const endTime = new Date();
const startTime = new Date();
startTime.setDate(endTime.getDate() - 7);
// Retrieve a week of messages
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const queryOptions = {
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timeFilter: {
startTime,
endTime,
},
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};
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// Query the Store peer with options
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await node.store.queryWithOrderedCallback([decoder], callback, options);
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const storeQuery = node.store.queryGenerator([decoder, options]);
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```
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:::info
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The `timeFilter` option significantly reduces message retrieval performance. To optimise it, consider resuming message retrieval using a [cursor ](#cursor ) that starts from the last seen message.
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:::
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:::tip Congratulations!
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You have successfully retrieved and filtered historical messages on a Light Node using the `Store` protocol. Have a look at the [store-js ](https://github.com/waku-org/js-waku-examples/tree/master/examples/store-js ) and [store-reactjs-chat ](https://github.com/waku-org/js-waku-examples/tree/master/examples/store-reactjs-chat ) examples for working demos.
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:::