Replaced plotly with matplotlib

node-example/README.md

@@ -15,7 +15,7 @@ git clone https://github.com/graalvm/graalvm-demos
 cd graalvm-demos/node-example
 ```
 
-Build the application before running. You can manually execute `npm install plotly`, but there's also a `build.sh` script included for your convenience.
+Build the application before running. The application requires python libraries for plotting the graph. You can manually execute all the commands from `build.sh` file line-by-line, but that is more convenient to execute `build.sh` script as it is shown below.
 
 Execute:
 ```
@@ -52,12 +52,4 @@ This will perform 50 requests to the server and print results of benchmarking.
 
 ## Notes about the application
 
-This application uses [Plotly](https://plot.ly) library to plot the graph. Plotly provides API for plotting graphs, and requires username and API key indicated.
-
-To get username and API key, proceed to the [Plotly](https://chart-studio.plot.ly/settings/api#/) site, log in or sign up, go to Settings->API Keys and click on `Regenerate Key` button. Then copy your username and API key and paste them there, on the top of the `taylor.js` file:
-
-```
-const plotly = require('plotly')('username', 'api_key');
-```
-
-This API key can be used 1000 times per 24h.
+This application uses [matplotnode](https://www.npmjs.com/package/matplotnode) package to plot the graph. This package requires Python 2.7 and matplotlib installed. Scripts to install them and their dependencies are in `build.sh` file.

node-example/build.sh

@@ -1,3 +1,8 @@
 #!/usr/bin/env bash
-
-npm install plotly
+sudo apt install python-dev
+sudo apt-get build-dep python-matplotlib
+sudo apt-get install python-pip
+sudo apt-get install python-tk
+python -m pip install -U pip
+sudo python -m pip install -U matplotlib
+npm install matplotnode

node-example/taylor.js

@@ -1,9 +1,13 @@
-const plotly = require('plotly')('username', 'api_key');
 const http = require('http');
+const plt = require('matplotnode');
+const fs = require('fs');
+
+const file = './plot.png';
 
 //-----------------------Creating-server------------------------------
 
 const server = http.createServer((req, res) => {
+ plt.close('all');
  outputSinGraph(res);
 });
 
@@ -53,47 +57,23 @@ function outputSinGraph(res) {
  return d;
  }
 
- //-----------------------Plotting-graph-------------------------------
 
- var layout = {
- title: {
- text: `Evaluations took ${time} nanoseconds.`,
- font: {
- family: 'Courier New, monospace',
- size: 24
- },
- xref: 'paper',
- x: 0.05,
- }
- }
+ //-----------------------Plotting-graph-------------------------------
 
- var trace1 = {
- x: data.x,
- y: data.y,
- type: "scatter"
- };
+ plt.title(`Evaluations took ${time} nanoseconds.`);
+ plt.plot(data.x, data.y, 'color=b', 'label=sin(x)');
+ plt.legend();
 
- var figure = { 
- 'data': [trace1],
- 'layout' : layout
- };
+ plt.save(file);
 
- var imgOpts = {
- format: 'png',
- width: 1000,
- height: 500
- };
-
- plotly.getImage(figure, imgOpts, function (error, imageStream) {
- if (error) return console.log (error);
- res.writeHead(200, {'Content-Type': 'image/png'});
- imageStream.pipe(res);
- });
+ let imageStream = fs.createReadStream(file);
+ res.writeHead(200, {'Content-Type': 'image/png'});
+ imageStream.pipe(res);
 }
 
 //-----------------------Time-measurement-----------------------------
 
 function getNanoSecTime() {
- var hrTime = process.hrtime();
+ let hrTime = process.hrtime();
  return hrTime[0] * 1000000000 + hrTime[1];
 }