# Construct a social graph with Relation Protocol

We will demonstrate how to quickly build a graph-indexer to listen to on-chain data, store RDF data using neo4j graph database, and query and show a graph.

## Dependencies

Before we start, you should have [Node.js](https://nodejs.org/en/) installed on your computer.

## Deploy neo4j

Please refer to [this document](https://docs.relationlabs.ai/protocol/indexer/build-graph) for neo4j deployment.

## A simple Graph Indexer

We will use nodejs & neo4j-driver to proceed.

> This example will listen to the RDF data in between blocks 8701627 and 8702627 on the Goerli network.

1. Create a new project and install the neo4j-driver and ethers(v5) libraries.

```shell
mkdir graph-indexer
cd graph-indexer
npm init -y
npm install neo4j-driver ethers@5
```

2. Create an app.js to listen to data on the blockchain:

```javascript
const ethers = require('ethers')
const rpc = 'https://rpc.ankr.com/eth_goerli'
let abi = ['event CreateRDF(uint256 indexed tokenId, string rdfStatements)']
const provider = new ethers.providers.JsonRpcProvider(rpc)
const iface = new ethers.utils.Interface(abi)
const filter = {}

// connect neo4j-server
const neo4j = require('neo4j-driver')
const uri = 'bolt://localhost:7687'
// neo4j's default user/password are: neo4j/neo4j
const user = 'neo4j'
const password = 'neo4j'
const driver = neo4j.driver(uri, neo4j.auth.basic(user, password))
const session = driver.session()

// Insert rdf into neo4j
async function insertRdfToNeo4j(rdfString) {
    const session = driver.session()
    try {
        const result = await session.run(
            `CALL n10s.rdf.import.inline("PREFIX : <http://relationlabs.ai/entity/>
    PREFIX p: <http://relationlabs.ai/property/>
    prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
    prefix xsd: <http://www.w3.org/2001/XMLSchema#>
    prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>

    ${rdfString}","Turtle");`
        )
        return result
    } catch (error) {}
    session.close()
}

// Listen to new events on the blockchain
provider.on(filter, async (e) => {
  try {
    let event = iface.parseLog(e)
    if (event) {
      const rdf = event.args[1]
      //  Parse
      //  todo: Execute your own business logic. You can filter the RDF data you need.
      //  Insert into the database.
      const res = await insertRdfToNeo4j(rdf)
    }
  } catch (error) {}
})

// You can also specify a filter for data.
const logFilter = {
  fromBlock: 8701627,
  toBlock: 8702627,
  topics: [
        utils.id("CreateRDF(uint256,string)"),
    ]
}
provider
  .getLogs(logFilter)
  .then(function (logs) {
    for (let index = 0; index < logs.length; index++) {
      try {
        const log = logs[index]
        const event = iface.parseLog(log)
        if (event) {
          const rdf = event.args[1]
          insertRdfToNeo4j(rdf)
        }
      } catch (error) {}
    }
  })
  .catch(function (err) {
    console.log(err)
  })

```

3. Run the Graph Indexer

```shell
node app.js
```

Once the data is inserted, open [http://localhost:7474/browser/](http://http://localhost:7474/browser/) in your browser, and input `match (n) return n` in the interface to query all the data.

To query all the "follow" relationship, you can use:

```shell
MATCH (node1)-[rel:p__following]->(node2)
RETURN node1,node2
```

You will see the following graph:

<figure><img src="/files/bUzLz8o78ti2N1UhkNuk" alt=""><figcaption><p>Figure 8-1 Social Graph</p></figcaption></figure>


---

# Agent Instructions: Querying This Documentation

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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://relationlabs.gitbook.io/protocol/integrations/quick_start_index.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.