#!/bin/bash
PUBLIC_KEY='your_public_key'
PRIVATE_KEY='your_private_key'
JSON="{ 
\"version\" : 3,
\"public_key\" : \"${PUBLIC_KEY}\", 
\"action\" : \"pay\", 
\"amount\" : 1, 
\"currency\" : \"USD\",
\"description\" : \"description text\",
\"order_id\" : \"order_id_1\"
}"
# DATA is base64_encode result from JSON string
DATA=$(echo -n ${JSON} | base64)
# SIGNATURE is base64 encode result from sha1 binary hash from concatenate string ${PRIVATE_KEY}${DATA}${PRIVATE_KEY}
SIGNATURE=$(echo -n "${PRIVATE_KEY}${DATA}${PRIVATE_KEY}" | openssl dgst -binary -sha1 | base64)
echo "data: ${DATA}"
echo "signature: ${SIGNATURE}"

# DATA in this example
# eyAidmVyc2lvbiIgOiAzLCAicHVibGljX2tleSIgOiAieW91cl9wdWJsaWNfa2V5IiwgImFjdGlv
# biIgOiAicGF5IiwgImFtb3VudCIgOiAxLCAiY3VycmVuY3kiIDogIlVTRCIsICJkZXNjcmlwdGlv
# biIgOiAiZGVzY3JpcHRpb24gdGV4dCIsICJvcmRlcl9pZCIgOiAib3JkZXJfaWRfMSIgfQ==

# SIGNATURE in this example
# QvJD5u9Fg55PCx/Hdz6lzWtYwcI=

$liqpay = new LiqPay($public_key, $private_key);
$html = $liqpay->cnb_form(array(
'action'         => 'pay',
'amount'         => '1',
'currency'       => 'USD',
'description'    => 'description text',
'order_id'       => 'order_id_1',
'version'        => '3'
));

HashMap<String, String> params = new HashMap<String, String>();
params.put("action", "pay");
params.put("amount", "1");
params.put("currency", "USD");
params.put("description", "description text");
params.put("order_id", "order_id_1"); 
params.put("version", "3"); 
LiqPay liqpay = new LiqPay(PUBLIC_KEY, PRIVATE_KEY);
String html = liqpay.cnb_form(params);    
System.out.println(html);

 
liqpay = LiqPay(public_key, private_key)
html = liqpay.cnb_form({
"action"         : "pay",
"amount"         : "1",
"currency"       : "USD",
"description"    : "description text",
"order_id"       : "order_id_1",
"version"        : "3"
})

liqpay = Liqpay::Liqpay.new(
:public_key  => 'public_key',
:private_key => 'private_key'
)
html = liqpay.cnb_form({
:action         => "pay",
:amount         => "1",
:currency       => "USD",
:description    => "description text",
:order_id       => "order_id_1",
:version        => "3"
})

LiqPay = liqpay:init(PublicKey, PrivateKey),
Html = liqpay:cnb_form([ 
{<<"action">>,      <<"pay">>}, 
{<<"amount">>,      <<"1">>}, 
{<<"currency">>,    <<"USD">>}, 
{<<"description">>, <<"description text">>}, 
{<<"order_id">>,    <<"order_id_1">>},
{<<"version">>,     <<"3">>}
], LiqPay)

var LiqPay = require('liqpay');
var liqpay = new LiqPay(public_key, private_key);
var html = liqpay.cnb_form({
'action'         : 'pay',
'amount'         : '1',
'currency'       : 'USD',
'description'    : 'description text',
'order_id'       : 'order_id_1',
'version'        : '3'
});

my $liqpay = Liqpay->new($public_key,$private_key);
my $html = $liqpay->cnb_form({
'action'         => 'pay',
'amount'         => '1',
'currency'       => 'USD',
'description'    => 'description text',
'order_id'       => 'order_id_1',
'version'        => '3'
}
);

func main() {
    var c = liqpay.New("my_public_key", "my_private_key", nil)
    
    request := map[string]interface{}{
        "action":      "pay",
        "version":     3,
        "public_key":  "my_public_key",
        "amount":      3,
        "currency":    "USD",
        "description": "payment description",
        "order_id":    "67014f40-8d58-4dc8-b7e2-e8fe1afb48",
    }
        
    resp, err := c.RenderForm(request)
    if err != nil {
        fmt.Printf("error %v", err.Error())

        return
    }

    fmt.Printf("response: %#v", resp)
}

<form method="POST" action="https://www.liqpay.ua/api/3/checkout" 
accept-charset="utf-8">
<input type="hidden" name="data" value="eyAidmVyc2lvbiIgOiAzLCAicHVibGljX2tleSIgOiAieW91cl9wdWJsaWNfa2V5IiwgImFjdGlv
biIgOiAicGF5IiwgImFtb3VudCIgOiAxLCAiY3VycmVuY3kiIDogIlVTRCIsICJkZXNjcmlwdGlv
biIgOiAiZGVzY3JpcHRpb24gdGV4dCIsICJvcmRlcl9pZCIgOiAib3JkZXJfaWRfMSIgfQ=="/>
<input type="hidden" name="signature" value="QvJD5u9Fg55PCx/Hdz6lzWtYwcI="/>
<input type="image" 
src="//static.liqpay.ua/buttons/payUk.png"/>
</form>