Arduino Yun to Parse.com (Process, curl).

parse.ino

// Original:
// http://hypernephelist.com/2014/08/19/https_on_arduino_yun.html

// Libraries
#include <Process.h>

// Literals
// #define DEBUG

// Constants
const char *PARSE_API = "api.parse.com";
const char *PARSE_APP = "_YOUR_PARSE_APP_";
const char *PARSE_CLASS = "Temperature";
const char *PARSE_KEY = "_YOUR_PARSE_REST_KEY_";
const char *PARSE_VERSION = "1";

// Counter
int counter = 0;

// Leverage Yun Linux (curl)
Process process;

// Buffer for parameters
char buffer[80];

// Setup
void setup() 
{
  // Bridge communication
  Bridge.begin();
  
  // Console debugging
  // Wait for console
  #ifdef DEBUG
    Console.begin();  
    while( !Console ) {;}
  #endif
}

// Loop
void loop() 
{
  // Increment counter
  counter = counter + 1;
  
  // Put value in data store
  request( counter );
  wait();
  response();

  // Wait for next sample
  delay( 5000 );
}

// Send the data to Parse.com
void request( int value )
{
  // Curl request per Parse.com documentation
  /*
  curl -X POST \
  -H "X-Parse-Application-Id: APPLICATION_ID" \
  -H "X-Parse-REST-API-Key: REST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"reading":123}' \
  https://api.parse.com/1/classes/Temperature  
  */  

  // Build curl command line
  // Includes HTTPS support
  // POST
  // JSON
  process.begin( "curl" );
  process.addParameter( "-k" );
  process.addParameter( "-X" );
  process.addParameter( "POST" );
  process.addParameter( "-H" );
  process.addParameter( "Content-Type:application/json" );
 
  // Parse.com application
  process.addParameter( "-H" );
  sprintf( buffer, "X-Parse-Application-Id: %s", PARSE_APP );
  process.addParameter( buffer );
  
  // Parse.com key
  process.addParameter( "-H" );
  sprintf( buffer, "X-Parse-REST-API-Key: %s", PARSE_KEY );
  process.addParameter( buffer );  
 
  // JSON body
  process.addParameter( "-d" );
  sprintf( buffer, "{\"reading\": %d}", value );
  process.addParameter( buffer );
 
  // URI
  sprintf( buffer, "https://%s/%s/classes/%s", PARSE_API, PARSE_VERSION, PARSE_CLASS );
  process.addParameter( buffer );  

  // Run the command 
  // Synchronous
  process.run();
}

// Response from Parse.com
void response()
{
  bool print = true;
  char c;
  
  // While there is data to read
  while( process.available() ) 
  {
    // Get character
    c = process.read();
   
    // Debugging
    #ifdef DEBUG 
      // Print until newline
      if( c == '\n' )
      {
        print = false;
      }      
    
      // Not newline yet
      // Print to console
      if( print )
      {
        Console.print( c );
      }
    #endif
  }
  
  // Debugging
  #ifdef DEBUG
    // Newline for console
    Console.println();
  #endif
}

// Wait for a response from Parse.com
void wait()
{
  // Periodically check curl process
  while( !process.available() ) 
  {
    delay( 100 );
  }
}