Skip to content
Branch: master
Find file History
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.

What is it?

This package is an example of how is it possible to integrate the fluence cluster with a data source.

streamr has been taken as a data source.

Take a look at how we can take data from a source and insert it into LlamaDB, that covered under the fluence cluster and get some aggregated information.

What is fluence

Take a look at the main repo for necessary information.

Here you can find how to create a cluster and do the first steps of how to use fluence.

Step by step

To run code from this repo:

  1. Clone repo to any directory
  2. cd to this directory
  3. Run npm install command
  4. Run npm run build command
  5. Open ./bundle/index.html in your browser
  6. Open terminal in a browser
  7. Call getData() to open stream and insert rows of data from it
  8. Call getCount() to count number of rows
  9. Call getMax(parameter) to get maximum of a parameter, where parameter could be one of pm25, pm10, no2, o3

To write code from scratch:

  1. Initialize project with npm init
  2. Install fluence and streamr clients with npm install --save fluence streamr-client
  3. Create index.js file and open it with any editor
  4. Import clients and initialize them
import StreamrClient from 'streamr-client'
import * as fluence from "fluence"

// with default options it will be connected to `wss://`
const streamrClient = new StreamrClient();

// creates session with predefined credentials, cluster should be started already
const fluenceSession = fluence.directConnect("localhost", 29057);
  1. Create table in LlamaDB in the fluence cluster
// it is a simplified query, there is more parameters, full query is in the repo
const createTableQuery = "CREATE TABLE polution_uusimaa(id varchar(128), location varchar(128), parameter varchar(128), value double, unit varchar(128))";

    .result() // to return promise and wait for result we need to call `result()` function
    .then((r) => console.log(r.asString())); // `asString()` decodes bytes format to string
  1. Explain of how we will inserts new data to LlamaDB
function genInsertQuery(data) {
    const query = `INSERT INTO polution_uusimaa VALUES ('${}', '${data.location}', '${data.parameter}', ${data.value}, '${JSON.stringify(data.unit)}')`;
    console.log("Query: " + query);
    return query;
  1. Get data
            stream: 'dVoD8tzLR6KLJ-z_Pz8pMQ', // it is an id of stream of pollution data in Uusimaa, Finland
            resend_last: 100 // will send last 100 rows
        (message, metadata) => {
            const query = insertQuery(message); // generates query
            fluenceSession.request(query); // and inserts it in into LlamaDB
  1. As an example, create functions that will count our data and get maximum:
function getCount() {
    const query = "select count(*) from polution_uusimaa";
    fluenceSession.request(query).result().then((r) => {
        console.log("Data count: " + r.asString().split("\n")[1])

 * Get maximum value of parameter
 * @param parameter [pm25, pm10, no2, o3]
function getMax(parameter) {
    const query = `select max(value) from polution_uusimaa where parameter = '${parameter}'`;
    fluenceSession.request(query).result().then((r) => {
        console.log(`Maximum of ${parameter}: ${r.asString().split("\n")[1]}`);
You can’t perform that action at this time.