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Displaying the bitcoin price using the coindesk API

by hotshed71

In this article we will get the price of Bitcoin using the coindesk bpi api, this is  a free api that also does not require that you signup and have to use a key.

The CoinDesk Bitcoin Price Index (XBP) represents an average of bitcoin prices across leading global exchanges that meet criteria specified by the XBP

You can visit https://api.coindesk.com/v1/bpi/currentprice.json

This is the output you will see, something similar to this

{“time”:{“updated”:”Jan 23, 2021 21:09:00 UTC”,”updatedISO”:”2021-01-23T21:09:00+00:00″,”updateduk”:”Jan 23, 2021 at 21:09 GMT”},”disclaimer”:”This data was produced from the CoinDesk Bitcoin Price Index (USD). Non-USD currency data converted using hourly conversion rate from openexchangerates.org”,”chartName”:”Bitcoin”,”bpi”:{“USD”:{“code”:”USD”,”symbol”:”$”,”rate”:”32,161.5533″,”description”:”United States Dollar”,”rate_float”:32161.5533},”GBP”:{“code”:”GBP”,”symbol”:”£”,”rate”:”23,507.1688″,”description”:”British Pound Sterling”,”rate_float”:23507.1688},”EUR”:{“code”:”EUR”,”symbol”:”€”,”rate”:”26,417.1461″,”description”:”Euro”,”rate_float”:26417.1461}}}

You can also visit https://api.coindesk.com/v1/bpi/supported-currencies.json to get a list of available FIAT currencies

You can then access this by using an endpoint like the folllowing : https://api.coindesk.com/v1/bpi/currentprice/.json

So you could access the Chinese Yuan by typing the following in https://api.coindesk.com/v1/bpi/currentprice/CNY.json

Install the requests library

Requests is a library for HTTP which makes accessing web sites and HTTP APIs easy. The simplest way to install requests is using PIP. To install requests run this command:

pip3 install requests

Testing the API

Put the following code in a file with a .py extension. I called mine bitcoinprice.py and it looks like this

import requests # http://docs.python-requests.org/en/master/
response = requests.get('https://api.coindesk.com/v1/bpi/currentprice.json')
data = response.json()
print(data)

Lets look through this example one line at a time

  • 1 imports the requests library we installed.
  • 2 calls the get function of the requests library and passes in the coindesk api  URL as a parameter. It assigns what is returned to a variable called response.
  • 3 calls the json() method on the response object we just created. This method returns the JSON we received in the API call. It assigns the results to a variable called data.
  • 4 prints the returned JSON data on the command line

Open a command line and run the script using your Python interpreter. Like this.

python bitcoinprice.py

This is what you should see

coindesk api json

coindesk api json

Get the Bitcoin price in various currencies

Now take the bitcoinprice.py and update is as follows

import requests # http://docs.python-requests.org/en/master/

response = requests.get('https://api.coindesk.com/v1/bpi/currentprice.json')

data = response.json()
#print(data)
print("1 Bitcoin is worth")
print(data["bpi"]["USD"]["rate"] + " Dollars")
print(data["bpi"]["EUR"]["rate"] + " Euros")
print(data["bpi"]["GBP"]["rate"] + " Pounds")

You will see that there are a few new lines added in

print(data["bpi"]["USD"]["rate"] + " Dollars")

We want to get the rate from the JSON that is returned and we want this in dollars, euros and pounds

You should see something like

C:\Python38-32>python bitcoinprice.py
1 Bitcoin is worth
31,980.4783 Dollars
26,268.4131 Euros
23,374.8194 Pounds

Cryptocurrency Blockchain in 30 minutes in C++

by hotshed71

Have you ever wondered what it would take to create a cryptocurrency coin or token yourself

This is an example in C++ of the basic building “blocks” of a blockchain.

Source On Github (after clean up in 2nd video):

https://github.com/jonnylynchy/Blockchain-C-Plus-Plus-Example

ESP8266 module and OLED bitcoin ticker

by hotshed71

In this example we will display the price in USD of 1 bitcoin, the data is taken from coindesk's API and displayed on an oled display.

This is similar to our previous examples, you do not need to use a Wemos mini or the OLED shield below but this makes the project easier to build

Here is the oled shield for the Wemos mini

Here is the wemos mini

Code

[c]

#include <ESP8266WiFi.h>
#include <Wire.h>
#include <SFE_MicroOLED.h>
#include <ArduinoJson.h>

const char* ssid = “iainhendry”;
const char* pass = “iain061271”;
#define PIN_RESET 255 //
#define DC_JUMPER 0 // I2C Addres: 0 – 0x3C, 1 – 0x3D
String id;
String value;
String json;

MicroOLED oled(PIN_RESET, DC_JUMPER); // I2C Example

WiFiClient client;

// delay between updates
const unsigned long postingInterval = 60L * 1000L;
unsigned long lastConnectionTime = 0;

void setup()
{
delay(100);
Serial.begin(115200);
Serial.println();
Serial.println();
Serial.print(“Connecting to “);
Serial.println(ssid);
WiFi.begin(ssid, pass);
while (WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(“.”);
}
Serial.println(“”);
Serial.println(“WiFi connected”);
Serial.println(“IP address: “);
Serial.println(WiFi.localIP());

Serial.print(“Connecting to “);

oled.begin();
oled.clear(ALL);
oled.setCursor(0,0);
oled.display();
oled.clear(PAGE);
oled.clear(ALL);
oled.print(“Bitcoin price”);
oled.setCursor(0,1);
oled.print(“loading..”);
oled.display(); // Display what's in the buffer (splashscreen)
delay(50);

}

int check_connect = 0;

void httpRequest()
{
client.stop();

// if there's a successful connection:
if (client.connect(“api.coindesk.com”, 80))
{
Serial.println(“connecting…”);
client.println(“GET /v1/bpi/currentprice.json HTTP/1.1”);
client.println(“Host: api.coindesk.com”);
client.println(“User-Agent: ESP8266/1.1”);
client.println(“Connection: close”);
client.println();
lastConnectionTime = millis();
}
else
{
// if you couldn't make a connection:
Serial.println(“connection failed”);
}
}

void loop()
{
int cnt;

if (cnt++ == 10000)
{
cnt = 0;
if (check_connect++ == 50)
{
check_connect = 0;
if (WiFi.status() != WL_CONNECTED)
{
}
}
}

if (millis() – lastConnectionTime > postingInterval)
{
httpRequest();
unsigned int i = 0; //timeout counter
int n = 1; // char counter
char json[500] =”{“;

while (!client.find(“\”USD\”:{“)){}

while (i<20000)
{
if (client.available())
{
char c = client.read();
json[n]=c;
if (c=='}') break;
n++;
i=0;
}
i++;
}

StaticJsonBuffer<500> jsonBuffer;
JsonObject& root = jsonBuffer.parseObject(json);

String newjson = root[“code”];
String value = root[“rate”];
id = newjson.substring(9,12);

// value = newjson.substring(41,51);
oled.display();
oled.clear(PAGE); // Clear the display's internal memory
oled.clear(ALL); // Clear the library's display buffer
oled.setCursor(0,1);
oled.print(value);
oled.display();

id=””;
value=””;
}
}

[/c]

testing

You should see something like this on the oled display

esp8266 bitcoin ticker

esp8266 bitcoin ticker

Links

Here are some of the products I used

Smart Electronics D1 mini – Mini NodeMcu 4M bytes Lua WIFI Internet of Things development board based ESP8266 by WeMos

0.66″ inch For Wemos Oled 64X48 IIC I2C LCD OLED LED Dispaly Shield for Arduino Compatible For WeMos D1 Mini SSD1306 OLED Shield

An improved ESP8266 and Bitcoin price ticker example

by hotshed71

This is similar to our previous ESP8266 bitcoin example – Basic ESP8266 and bitcoin price example

We used the same Wemos board as in the previous example

In this example we use ArduinoJson library to parse the json response from coindesk. A better approach than the previous example

Again you will have to change the username and password for your wifi credentials

const char* ssid = “your username here”;
const char* pass = “your password here”;

Again we will display the results via the serial monitor

Code

Open the library manager and add support for the ArduinoJson library to the Arduino IDE

Copy and paste the following code into the Arduino IDE, build and program your board

[c]

#include <ESP8266WiFi.h>
#include <ArduinoJson.h>

const char* ssid = “your username here”;
const char* pass = “your password here”;

String id;
String value;
String json;

WiFiClient client;

const unsigned long postingInterval = 60L * 1000L;
unsigned long lastConnectionTime = 0;

void setup()
{
delay(100);
Serial.begin(115200);
Serial.println();
Serial.println();
Serial.print(“Connecting to “);
Serial.println(ssid);
WiFi.begin(ssid, pass);
while (WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(“.”);
}
Serial.println(“”);
Serial.println(“WiFi connected”);
Serial.println(“IP address: “);
Serial.println(WiFi.localIP());
delay(50);

}

int check_connect = 0;

void httpRequest()
{
client.stop();

// if there's a successful connection:
if (client.connect(“api.coindesk.com”, 80))
{
Serial.println(“connecting…”);
client.println(“GET /v1/bpi/currentprice.json HTTP/1.1”);
client.println(“Host: api.coindesk.com”);
client.println(“User-Agent: ESP8266/1.1”);
client.println(“Connection: close”);
client.println();
lastConnectionTime = millis();
}
else
{
// if you couldn't make a connection:
Serial.println(“connection failed”);
}
}

void loop()
{
int cnt;

if (cnt++ == 10000) {
cnt = 0;
if (check_connect++ == 50) {
check_connect = 0;
if (WiFi.status() != WL_CONNECTED) {

}
}
}

if (millis() – lastConnectionTime > postingInterval) {
httpRequest();
unsigned int i = 0; //timeout counter
int n = 1; // char counter
char json[500] =”{“;

while (!client.find(“\”USD\”:{“)){}

while (i<20000) {
if (client.available()) {
char c = client.read();
json[n]=c;
if (c=='}') break;
n++;
i=0;
}
i++;
}

Serial.println(json);

StaticJsonBuffer<500> jsonBuffer;
JsonObject& root = jsonBuffer.parseObject(json);

String newjson = root[“code”];
String value = root[“rate”];
id = newjson.substring(9,12);

Serial.print(“1 bitcoin = USD value : “);
Serial.println(value);

id=””;
value=””;
}
}

[/c]

 

Testing

Open the serial monitor and you should see something like this if everything goes to plan

Connecting to ****************
…………..
WiFi connected
IP address:
192.168.1.15
connecting…
{“code”:”USD”,”symbol”:”$”,”rate”:”9,692.3175″,”description”:”United States Dollar”,”rate_float”:9692.3175}
1 bitcoin = USD value : 9,692.3175

Basic ESP8266 and bitcoin price example

by hotshed71

This example was sent to me via one of my electronics sites, this example use an ESP8266 development board, there are many examples of these on the net that can be bought, I personal use the Wemos range

In the code example below we use the coindesk api, the json is parsed and then the results are displayed via the serial monitor. You will need a wifi connection for this example and need to update the following lines with your wifi details

const char* ssid = “your ssid here”; // insert your SSID
const char* password = “your password here”; // insert your password

There are better examples, we will look at them later using the ESP8266 and many other development boards such as ESP32, Arduino and Raspberry Pi.

Code

[c]

#include <ESP8266WiFi.h>

const char* ssid = “your ssid here”; // insert your SSID
const char* password = “your password here”; // insert your password

const char* host = “api.coindesk.com”;
String url = “/v1/bpi/currentprice.json”;

String id;
String value;

void setup()
{
Serial.begin(115200);
delay(10);

Serial.println(“Bitcoin Prices”);

//We start by connecting to a WiFi network

Serial.println();
Serial.print(“Connecting to “);
Serial.println(ssid);

WiFi.begin(ssid, password);

while (WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(“.”);
}

Serial.println(“”);
Serial.println(“WiFi connected”);
Serial.println(“IP address: “);
Serial.println(WiFi.localIP());
}

void loop()
{
Serial.println();
Serial.print(“connecting to “);
Serial.println(host);

WiFiClient client;
const int httpPort = 80;
if (!client.connect(host, httpPort))
{
Serial.println(“connection failed”);
return;
}

Serial.print(“Requesting URL: “);
Serial.println(url);

// This will send the request to the server
client.print(String(“GET “) + url + ” HTTP/1.1\r\n” +
“Host: ” + host + “\r\n” +
“Connection: close\r\n\r\n”);
delay(10);

unsigned int i = 0;
int n = 1;
char json[500] =”{“;
while (!client.find(“\”USD\”:{“)){}
while (i<600)
{
if(client.available())
{
char c = client.read();
json[n]=c;
if(c=='}') break;
n++;
i=0;
}
i++;
}

Serial.println(json);
id += json;
value += json;

id = id.substring(9,12);
Serial.print(id);
Serial.print(“= “);

value = value.substring(99,106);
Serial.println(value);

id=””;
value=””;

Serial.println(“closing”);
delay(60000);
}

[/c]

Testing

Open the serial monitor and you should see something like this

Connecting to **********
…..
WiFi connected
IP address:
192.168.1.15

connecting to api.coindesk.com
Requesting URL: /v1/bpi/currentprice.json
{“code”:”USD”,”symbol”:”$”,”rate”:”9,644.0638″,”description”:”United States Dollar”,”rate_float”:9644.0638}
USD= “:9644.
closing connection

connecting to api.coindesk.com
Requesting URL: /v1/bpi/currentprice.json
{“code”:”USD”,”symbol”:”$”,”rate”:”9,640.6238″,”description”:”United States Dollar”,”rate_float”:9640.6238}
USD= “:9640.
closing connection

Bitpay conversions using PHP

by hotshed71

In this example we will display some conversions using bitpays api. the url we are interested in is located at https://bitpay.com/api/rates

This is abbreviated output
[
{“code”:”BTC”,”name”:”Bitcoin”,”rate”:1},
{“code”:”BCH”,”name”:”Bitcoin Cash”,”rate”:6.327061},
{“code”:”USD”,”name”:”US Dollar”,”rate”:9095.53},
{“code”:”EUR”,”name”:”Eurozone Euro”,”rate”:7609.91},
{“code”:”GBP”,”name”:”Pound Sterling”,”rate”:6698.966991},
{“code”:”JPY”,”name”:”Japanese Yen”,”rate”:998393.589275},

Th example below will display conversions but can be affected if the api changes, in the example below you will see lines of code like the following

$rateUSD = $data[2][“rate”];

which corresponds to

{“code”:”USD”,”name”:”US Dollar”,”rate”:9095.53},

Obviously if bitpay were to change this it would display incorrect results

Code

[php]

<?php
$url = “https://bitpay.com/api/rates”;
$json = file_get_contents($url);
$data = json_decode($json, TRUE);
$rateUSD = $data[2][“rate”];
$rateBCH = $data[1][“rate”];
$rateEUR = $data[3][“rate”];
$rateGBP = $data[4][“rate”];
?>
BTC/USD: <?=$rateUSD?>
<br>
BTC/Bitcoin Cash: <?=$rateBCH?>
<br>
BTC/EUR: <?=$rateEUR?>
<br>
BTC/GBP : <?=$rateGBP?>

[/php]

 

Output

You should see something like this

BTC/USD: 9095.03
BTC/Bitcoin Cash: 6.326933
BTC/EUR: 7610.18
BTC/GBP : 6698.598735

Bitcoin to US Dollar conversion in PHP

by hotshed71

In this example we will use cryptonator's api to show a conversion from bitcoin to USD.

For more information about the api visit – https://www.cryptonator.com/api/. From the website

Cryptonator provides unique volume of cryptocurrency exchange rates data, which is delivered in easy-to-integrate JSON format via simple HTTPS requests. Prices are updated every 30 seconds, covering 300+ cryptocurrencies across 62 exchanges.

You can get a list of cryptocurrencies supported by visiting http://www.cryptonator.com/api/currencies

Lets take a look at an example in PHP

Code

[php]

<?php
$url = “https://www.cryptonator.com/api/ticker/btc-usd”;
$data = json_decode(file_get_contents($url), true);
$ticker = $data[‘ticker'];
$latest_price = $ticker[‘price'];
echo “1 Bitcoin = ” . “$latest_price” . ” US Dollars”;
?>

<html>
<head>
<title>BTC to USd Price Converter</title>
<meta content='10' http-equiv='refresh'/> <!– Reloads Page every 10 seconds –>
</head>

<body>
</body>

</html>

[/php]

 

Output

You should see something like this, depending on the current bitcoin price

1 Bitcoin = 9127.96826769 US Dollars