.. index:: 
	single: RingLibCurl; Introduction

=================
Using RingLibCurl
=================

In this chapter we will learn about using RingLibCurl

.. index:: 
	pair: RingLibCurl; Get Request

Get Request
===========

Example:

.. code-block:: ring

	load "libcurl.ring"	

	curl = curl_easy_init()

	curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1)
	curl_easy_setopt(curl, CURLOPT_URL, "http://ring-lang.sf.net")

	curl_easy_perform(curl)

	curl_easy_cleanup(curl)


.. index:: 
	pair: RingLibCurl; Post Request

Post Request
============

Example:

.. code-block:: ring

	load "libcurl.ring"

	curl = curl_easy_init()

	cPostThis = "page=4&Number1=4&Number2=5"
	curl_easy_setopt(curl, CURLOPT_URL, "http://localhost/ringapp/index.ring?page=3")
	curl_easy_setopt(curl, CURLOPT_POSTFIELDS, cPostThis)

	curl_easy_perform(curl)

	curl_easy_cleanup(curl)

.. index:: 
	pair: RingLibCurl; Facebook Login

Facebook Login 
==============

Example:

.. code-block:: ring

	load "libcurl.ring"

	see "Enter Email : " give $login_email 
	See "Enter Password : " give $login_pass

	curl = curl_easy_init()

	curl_easy_setopt(curl, CURLOPT_URL, 'https://www.facebook.com/login.php')
	curl_easy_setopt(curl, CURLOPT_POSTFIELDS,'charset_test=j u s t a t e s t'+
	' &email='+urlencode($login_email)+'&pass='+
	urlencode($login_pass)+'&login=Login')
	curl_easy_setopt(curl, CURLOPT_POST, 1)
	curl_easy_setopt(curl, CURLOPT_HEADER, 0)
	curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1)
	curl_easy_setopt(curl, CURLOPT_COOKIEJAR, "cookies.txt")
	curl_easy_setopt(curl, CURLOPT_COOKIEFILE, "cookies.txt")
	curl_easy_setopt(curl, CURLOPT_USERAGENT, "Mozilla/5.0 (Windows; U;"+
	" Windows NT 5.1; en-US; rv:1.8.1.3) Gecko/20070309 Firefox/2.0.0.3")
	curl_easy_setopt(curl, CURLOPT_REFERER, "http://www.facebook.com")
	curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, FALSE)
	curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 2)

	mylist = curl_slist_append(NULL,'Accept-Charset: utf-8')
	curl_slist_append(mylist,'Accept-Language: en-us,en;q=0.7,bn-bd;q=0.3')
	curl_slist_append(mylist,'Accept: text/xml,application/xml,'+
	'application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5')
	curl_easy_setopt(curl, CURLOPT_HTTPHEADER, mylist)

	curl_easy_setopt(curl, CURLOPT_COOKIESESSION, false)

	curl_easy_perform(curl)

	curl_easy_cleanup(curl)

	Func URLEncode cStr
		cOut = ""
		for x in cStr
			if isalnum(x)
				cOut += x
			but x = " "
				cOut += "+"
			else
				cOut += "%"+str2hex(x)
			ok
		next
		return cOut	

.. index:: 
	pair: RingLibCurl; Save output to string

Save Output to String
=====================

Example:

.. code-block:: ring

	load "libcurl.ring"

	curl = curl_easy_init()

	curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1)
	curl_easy_setopt(curl, CURLOPT_URL, "http://ring-lang.sf.net")

	cOutput = curl_easy_perform_silent(curl)

	See "Output:" + nl
	see cOutput

	curl_easy_cleanup(curl)

.. index:: 
	pair: RingLibCurl; Get Stock Data From Yahoo

Get Stock Data From Yahoo
=========================

Example:

.. code-block:: ring

	Load "libcurl.ring"

	### Part 1 --- Get Crumb and Cookie -----------------------------------------

	See "Start curl_easy_init(): "+ nl
	curl = curl_easy_init()                     ### >>> HANDLE >>> 01006BD0  CURL  0

		curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1)
		curl_easy_setopt(curl, CURLOPT_COOKIEJAR,  "cookies.txt")
		curl_easy_setopt(curl, CURLOPT_COOKIEFILE, "cookies.txt")
		curl_easy_setopt(curl, CURLOPT_URL, "https://finance.yahoo.com/quote/AMZN/history")

		###  HTML Data >>> STDOUT Window,  Use curl_easy_perform_silent >>> String

	cOutput = curl_easy_perform_silent(curl)    ### GO Get Data >>> String


	###   Extract Crumb from data
	###  "CrumbStore":{"crumb":"abcdefghijk"},

	if cOutput != NULL

		newStr1     = substr(cOutput, substr(cOutput, '"CrumbStore":{"crumb":"' ), 48 )
			nPosS   = substr(newStr1, ':"' ) ;  ### Start of crumb -2
			nPosE   = substr(newStr1, '"}' ) ;  ### End   of crumb
			nCount  = nPosE - nPosS -2          ### size  of crumb
		myCrumb     = substr(newStr1, nPosS +2, nCount)

		See "myCrumb.: |"+ myCrumb +"|" +nl
		
		### UniCode "\u002F" replace it with "/"
			if substr( myCrumb, "\u002F")
			   myCrumb = substr( myCrumb, "\u002F", "/")
			   See "myCrumb2: |"+ myCrumb +"|"+ nl
			ok

	else
		See "No Connectivity to Yahoo. Looking for Cookie and Crumb." +nl +nl
	ok

					
	### Part 2 --- Send URL with Crumb, and Cookie -----------------------------------------

		### Send URL+Crumb to Yahoo to fetch 1st stock history data,

		$url = "https://query1.finance.yahoo.com/v7/finance/download/AMZN"+
			"?period1=1277856000&period2=1498777545&interval=1wk" + 
			"&events=history&crumb=" + myCrumb

		curl_easy_setopt(curl, CURLOPT_URL, $url);
		cStr = curl_easy_perform_silent(curl)
		See cStr 

	curl_easy_cleanup(curl)  ### REMEMBER to CLOSE  CURL   


Output:

.. code-block:: ring

	myCrumb.: |sEEeW97mxvN|
	Date,Open,High,Low,Close,Adj Close,Volume
	2010-07-05,110.650002,117.480003,109.000000,117.260002,117.260002,21000400
	2010-07-12,117.809998,124.879997,117.320000,118.489998,118.489998,29407300
	2010-07-19,118.379997,121.250000,105.800003,118.870003,118.870003,74252100