Dynamic Bundle Discounts
This documentation explains the process of setting up Nosto - Dynamic Bundles for automatic discount, when a bundle is added to the cart on a Shopify store.
This release of bundle discounts will work only when all products from a bundle are added to the cart.
Nosto bundle templates needs the following mandatory variables (name intact) to be configured for proper functioning:
- 1.discount type - Defines the type of discount offered (percent/dollar)
- 2.discount value - Defines the amount/percent of discount offered on products
- 3.secured - Enable (true)/Disable (false)
hashbased authentication for bundle discounts. - 4.discountCurrentProduct - Defines whether the currently displayed product in PDP to be included & discounted when an associated bundle is added to cart. This flag is useful when bundles are displayed along with product details as depicted in image below:
PDP with Dynamic Bundle
In additional to these mandatory variables, any number of additional custom variables can be created and configured. A sample bundle template variable configuration is shown below
Dynamic Bundle template variables
In the above sample configuration, all the mandatory fields are highlighed and the "ATC button text" and "subtitle" are custom variables
Nosto JavaScript API addBundleToCartWithDiscount can be used to add the selected bundle to the cart with the following parameters:
- 1.Products selected in the bundle while adding to cart (items parameter)
- 2.Discount (type & value) configuration (discount parameter)
- 3.All the product IDs from the bundle (both selected and unselected) (bundleProducts parameter)
- 4.A hash value that is provided with the template out of the box (hash parameter). This hash value will later be used in conjuction with the secret key obtained from Nosto in order to authenticate the request for bundle discount.
Expanding items parameter, it should contain the following fields:
- 1.
productId- Product ID of the variant selected in the bundle - 2.
variantId- ID of the selected variant in the bundle - 3.
quantity- An optional field indicating product quantity offered in bundle. Defaults to 1. For bundles with only one quantity, this field can be omitted
(a) An example where all the products from a bundle are added to cart.
_targetWindow.Nosto.addBundleToCartWithDiscount({
items: [{
productId: '123456789',
variantId: '4123456098',
quantity: 3
}, {
productId: '987654321',
variantId: '4897122347',
quantity: 1
}],
discount: {
type: 'percent',
value: 10
},
bundleProducts: [ '123456789', '987654321' ],
hash: "$hash"
}, this)
in the above example, the configured discount value applies to all the products in the bundle.
Assume for example,
Product ID | Variant ID | Price |
|---|---|---|
123456789 | 4123456098 | 126$ |
987654321 | 4897122347 | 100$ |
discount type - percent discount value - 10
the final price customer pays: (126 * 3 * 0.1) + (100 * 1 * 0.1) => 340.2 + 90 => 430.2
Note:
Discount is applicable only when a bundle is added to the cart. Not applicable when products of a bundle are added individually.
(b) An example where NOT all the products from a bundle are added to cart.
_targetWindow.Nosto.addBundleToCartWithDiscount({
items: [{
productId: '123456789',
variantId: '4123456098'
}],
discount: {
type: 'percent',
value: 10
},
bundleProducts: [ '123456789', '987654321' ],
hash: "$hash"
}, this)
In the above example, quantity defaults to 1 and no discount is offered and the customer pays the actual price of the selected product
Please follow the steps below for setting up the line item script for handling the bundle discount request. (This has to be done manually for now, until next Nosto release)
- 1.Please follow the instructions here for installing and setting up Shopify Script Editor (make sure to select blank template and clear any existing code in the template)
- 2.Copy the code from here and add it to the line item script that we created in step (1). This code authenticates bundle discount requests and applies the discount only for genuine requests.
- 3.Copy the Nosto bundle discount script from here and add it to the line item script, below the authentication script (added from previous step)
- 4.The authentication logic has a GET_FROM_NOSTO variable. Value of this variable should be replaced with Nosto secret key. To get your secret key, please contact Nosto support
- 5.Click"Save and Publish" to publish the script
Nosto Bundle Script includes a commented testing section as shown below. This can be used to test the functionality of the bundle discount script. For testing, the script need to be unpublished in case if it's already published.
- Uncomment from
Input.cart.line_timestillend - The hash value marked with (GET_FROM_DEV_CONSOLE) can be retrieved from browser's network tab after adding a bundle to cart
- Replace "PROD_1", "PROD_2" etc., with the actual product IDs.
typecan bepercentordollar- Make sure to comment the lines after testing and before publishing the script again. This is an important step. Skipping this could cause issues with applying discounts in real-time.
# ================================================================
# Testing block. Uncomment the following lines to test the script
#Input.cart.line_items.each do |line_item|
# new_properties = { '_nosto_bundle' => { 'discount' => { 'type' => 'percent', 'value' => 10 }, 'bundle_products' => ["PROD_1", "PROD_2"], '_hash' => 'GET_FROM_DEV_CONSOLE' } }
# line_item.change_properties(new_properties, { :message => "" })
#end
# ================================================================
Nosto Dynamic Bundle configuration involves two important keys, hash and secret key. Hash key is used within the bundle template and can be accessed using predefined variation
$hash. Please avoid hard-coding this value anywhere inside the template. As dynamic bundle configurations are subjected to change, the hash key will also change accordingly. Hard-coding this key may break the functionality.Secret key, on the other hand, can be retrieved from "Dynamic Bundle Key" field in Nosto Admin Settings > Platform page. This value replaces GET_FROM_NOSTO placeholder in the Shopify line item script.
## [Authentication Script](#authentication-script)
```ruby
# Convert integer to binary string (32 bits) - modified from original
def bits(x, n = 32)
if x >= 0
return x.to_s(2).rjust(n, '0') # "%0#{n}b" % x does not work in Shopify
else
# Note: Ruby NOT function returns a negative number, and .to_s(2) displays this mathematical representation in base 2.
# Note: So to get the expected unsigned notation you need to get the individual bits instead.
# Note: When doing so, ignore the first bit because that's the sign bit.
# https://www.calleerlandsson.com/rubys-bitwise-operators/
return (n - 1).downto(0).map { |i| x[i] }.join
end
end
# Convert integer to hexadecimal string (32 bits)
def hex(i)
return i.to_s(16).rjust(8, "0")
end
# Convert string to binary string
def bitstring(string)
bytes = string.bytes # convert ascii characters to bytes (integers)
binary = bytes.map { |x| bits(x, 8) } # convert bytes to binary strings (8 bits in a byte)
return binary.join
end
# Convert input (hex, ascii) to array of bytes
def bytes(input, type)
case type
# Removed unused "binary" type from original
when "hex"
hex = input[2..-1] # trim 0x prefix
bytes = [hex].pack("H*").unpack("C*") # convert hex string to bytes
else
bytes = input.bytes # convert ASCII string to bytes
end
return bytes
end
# ----------
# Operations
# ----------
# Addition modulo 2**32
def add(*x)
total = x.inject(:+)
return total % 2 ** 32 # limits result of addition to 32 bits
end
# Rotate right (circular right shift)
def rotr(n, x)
right = (x >> n) # right shift
left = (x << 32 - n) # left shift
result = right | left # combine to create rotation effect
return result & (2 ** 32 - 1) # use mask to truncate result to 32 bits
end
# Shift right
def shr(n, x)
result = x >> n
return result
end
# ---------
# Functions - Combined rotations and shifts using operations above
# ---------
def sigma0(x)
return rotr(7, x) ^ rotr(18, x) ^ shr(3, x)
end
def sigma1(x)
return rotr(17, x) ^ rotr(19, x) ^ shr(10, x)
end
def usigma0(x)
return rotr(2, x) ^ rotr(13, x) ^ rotr(22, x)
end
def usigma1(x)
return rotr(6, x) ^ rotr(11, x) ^ rotr(25, x)
end
# Choice - Use first bit to choose the (1)second or (0)third bit
def ch(x, y, z)
return (x & y) ^ (~x & z)
end
# Majority - Result is the majority of the three bits
def maj(x, y, z)
return (x & y) ^ (x & z) ^ (y & z)
end
# -------------
# Preprocessing
# -------------
# Pad binary string message to multiple of 512 bits
def padding(message)
l = message.size # size of message (in bits)
k = (448 - l - 1) % 512 # pad with zeros up to 448 bits (64 bits short of 512 bits)
l64 = bits(l, 64) # binary representation of message size (64 bits in length)
return message + "1" + ("0" * k) + l64 # don't forget "1" bit between message and padding
end
# Cut padded message in to 512-bit message blocks - modified
def split(message, size = 512)
return (0..(message.length-1)/size).map{|i|message[i*size,size]} # message.scan(/.{#{size}}/)
end
# ----------------
# Message Schedule
# ----------------
# Calculate the 64 words for the message schedule from the message block
def calculate_schedule(block)
# The message block provides the first 16 words for the message schedule (512 bits / 32 bits = 16 words)
schedule = split(block,32).map { |w| w.to_i(2) } # convert from binary string to integer for calculations
# Calculate remaining 48 words
16.upto(63) do |i|
schedule << add(sigma1(schedule[i - 2]), schedule[i - 7], sigma0(schedule[i - 15]), schedule[i - 16])
end
return schedule
end
# ---------
# Constants
# ---------
# Constants = Cube roots of the first 64 prime numbers (first 32 bits of the fractional part)
K = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311].map { |prime| prime ** (1 / 3.0) }.map { |i| (i - i.floor) }.map { |i| (i * 2 ** 32).floor }
# -----------
# Compression - Run compression function on the message schedule and constants
# -----------
# Initial Hash Values = Square roots of the first 8 prime numbers (first 32 bits of the fractional part)
IV = [2, 3, 5, 7, 11, 13, 17, 19].map { |prime| prime ** (1 / 2.0) }.map { |i| (i - i.floor) }.map { |i| (i * 2 ** 32).floor }
def compression(initial, schedule, constants)
# state register - set initial values ready for the compression function
h = initial[7]
g = initial[6]
f = initial[5]
e = initial[4]
d = initial[3]
c = initial[2]
b = initial[1]
a = initial[0]
# compression function - update state for every word in the message schedule
64.times do |i|
# calculate temporary words
t1 = add(schedule[i], constants[i], usigma1(e), ch(e, f, g), h)
t2 = add(usigma0(a), maj(a, b, c))
# rotate state registers one position and add in temporary words
h = g
g = f
f = e
e = add(d, t1)
d = c
c = b
b = a
a = add(t1, t2)
end
# Final hash values are previous intermediate hash values added to output of compression function
hash = []
hash[7] = add(initial[7], h)
hash[6] = add(initial[6], g)
hash[5] = add(initial[5], f)
hash[4] = add(initial[4], e)
hash[3] = add(initial[3], d)
hash[2] = add(initial[2], c)
hash[1] = add(initial[1], b)
hash[0] = add(initial[0], a)
# return final state
return hash
end
# -------
# SHA-256 - Complete SHA-256 function
# -------
def sha256(string)
# 0. Convert String to Binary
# ---------------------------
message = bitstring(string)
# 1. Preprocessing
# ----------------
# Pad message
padded = padding(message)
# Split up in to 512 bit message blocks
blocks = split(padded, 512)
# 2. Hash Computation
# -------------------
# Set initial hash state using initial hash values
hash = IV
# For each message block
blocks.each do |block|
# Prepare 64 word message schedule
schedule = calculate_schedule(block)
# Remember starting hash values
initial = hash.clone
# Apply compression function to update hash values
hash = compression(initial, schedule, constants = K)
end
# 3. Result
# ---------
# Convert hash values to hexadecimal and concatenate
return hash.map { |w| w.to_s(16).rjust(8, '0') }.join
end
# Secret Key can be anything but must be consistent between this script and the frontend
SECRET_KEY="GET_FROM_NOSTO"
We offer support only when the script, given below, is used as-is. We don't offer support when the below script is modified, in any way.
# ================================ Script Code (do not edit) ================================
# ================================================================
# BundleSelector
#
# Finds any items that are part of the entered bundle and saves
# them.
# ================================================================
class BundleSelector
def initialize(bundle_items)
@bundle_items = bundle_items.reduce({}) do |acc, bundle_item|
acc[bundle_item[:product_id]] = {
cart_items: [],
quantity_needed: bundle_item[:quantity_needed],
total_quantity: 0,
}
acc
end
end
def build(cart)
cart.line_items.each do |line_item|
next if line_item.line_price_changed?
next unless @bundle_items[line_item.variant.product.id]
@bundle_items[line_item.variant.product.id][:cart_items].push(line_item)
@bundle_items[line_item.variant.product.id][:total_quantity] += line_item.quantity
end
@bundle_items
end
end
# ================================================================
# DiscountApplicator
#
# Applies the entered discount to the supplied line item.
# ================================================================
class DiscountApplicator
def initialize(discount_type, discount_amount, discount_message)
@discount_type = discount_type
@discount_message = discount_message
@discount_amount = if discount_type == :percent
1 - (discount_amount * 0.01)
else
Money.new(cents: 100) * discount_amount
end
end
def apply(line_item)
new_line_price = if @discount_type == :percent
line_item.line_price * @discount_amount
else
[line_item.line_price - (@discount_amount * line_item.quantity), Money.zero].max
end
line_item.change_line_price(new_line_price, message: @discount_message)
end
end
# ================================================================
# DiscountLoop
#
# Loops through the supplied line items and discounts the supplied
# number of items by the supplied discount.
# ================================================================
class DiscountLoop
def initialize(discount_applicator)
@discount_applicator = discount_applicator
end
def loop_items(cart, line_items, num_to_discount)
line_items.each_with_index do |line_item|
break if num_to_discount <= 0
if line_item.quantity > num_to_discount
split_line_item = line_item.split(take: num_to_discount)
@discount_applicator.apply(split_line_item)
position = cart.line_items.find_index(line_item)
cart.line_items.insert(position + 1, split_line_item)
break
else
@discount_applicator.apply(line_item)
num_to_discount -= line_item.quantity
end
end
end
end
# ================================================================
# BundleDiscountCampaign
#
# If the entered bundle is present, the entered discount is
# applied to each item in the bundle.
# ================================================================
class BundleDiscountCampaign
def initialize(campaigns)
@campaigns = campaigns
end
def run(cart)
@campaigns.each do |campaign|
bundle_selector = BundleSelector.new(campaign[:bundle_items])
bundle_items = bundle_selector.build(cart)
next if bundle_items.any? do |product_id, product_info|
product_info[:total_quantity] < product_info[:quantity_needed]
end
num_bundles = bundle_items.map do |product_id, product_info|
(product_info[:total_quantity] / product_info[:quantity_needed])
end
num_bundles = num_bundles.min.floor
discount_applicator = DiscountApplicator.new(
campaign[:discount_type],
campaign[:discount_amount],
campaign[:discount_message]
)
discount_loop = DiscountLoop.new(discount_applicator)
bundle_items.each do |product_id, product_info|
discount_loop.loop_items(
cart,
product_info[:cart_items],
(product_info[:quantity_needed] * num_bundles),
)
end
end
end
end
BUNDLE_ITEMS = []
discount_type = ""
discount_amount = 0.0
# ================================================================
# Testing block. Uncomment the following lines to test the script
#
#Input.cart.line_items.each do |line_item|
# new_properties = { '_nosto_bundle' => { 'discount' => { 'type' => 'dollar', 'value' => 10 }, 'bundle_products' => ["9172269958", "9172630790", "4719799304243"], '_hash' => '239a2b5bc60229ca8a6d9dd0f390a5bdc7098996506415e8637d3381e1935269' } }
# new_properties = { '_nosto_bundle' => { 'discount' => { 'type' => 'percent', 'value' => 5 }, 'bundle_products' => ["9172269958", "9172630790", "4719799304243"], '_hash' => '239a2b5bc60229ca8a6d9dd0f390a5bdc7098996506415e8637d3381e1935269' } }
# line_item.change_properties(new_properties, { :message => "discount test" })
#end
# ================================================================
class NostoBundleHandler
def initialize(line_items)
@nosto_bundle_products = []
if line_items.length() > 0
@nostoBundle = line_items.first.properties["_nosto_bundle"]
if @nostoBundle.nil? == false
@nosto_bundle_products = @nostoBundle["bundle_products"]
cleanup()
end
end
end
def isValid()
if @nostoBundle.to_a.empty? or @nostoBundle['_hash'].to_s.nil?
return false
end
data = @nosto_bundle_products.to_a.join(":")
if data.empty?
return false
end
discount = getDiscount()
if discount.nil?
return false
end
if discount['type'].nil? or discount['type'].to_s.strip.empty?
return false
end
if discount['value'].nil? or discount['value'].to_s.strip.empty?
return false
end
hashData = [data, discount['type'], discount['value'], SECRET_KEY].join(":")
SHA_HASH = sha256(hashData)
return SHA_HASH == @nostoBundle['_hash']
end
def cleanup()
@nosto_bundle_products = @nosto_bundle_products.map do |item|
if item.class == Integer
item
else
item.to_i
end
end
end
def isBundleActive()
cart_product_ids = Input.cart.line_items.map {
|item|item.variant.product.id
}
(@nosto_bundle_products.to_a - cart_product_ids).empty?
end
def isBundleItem(productId)
@nosto_bundle_products.to_a.include?(productId)
end
def getDiscount()
if @nostoBundle.nil? == false
@nostoBundle['discount']
else
nil
end
end
end
nostoBundleHandler = NostoBundleHandler.new(Input.cart.line_items)
if nostoBundleHandler.isValid()
isBundleActive = nostoBundleHandler.isBundleActive()
if isBundleActive
Input.cart.line_items.each do |line_item|
product_id = line_item.variant.product.id
if nostoBundleHandler.isBundleItem(product_id)
bundle_item = {}
bundle_item[:product_id] = product_id
bundle_item[:quantity_needed] = line_item.quantity
discountConfig = nostoBundleHandler.getDiscount()
if discount_type.empty?
unless discountConfig.nil?
discountType = discountConfig['type']
discount_type = discountType == 'percent' ? :percent : :dollar
discount_amount = discountConfig['value']
end
end
BUNDLE_ITEMS << bundle_item
end
end
end
@BUNDLE_DISCOUNTS = [{
:bundle_items => BUNDLE_ITEMS,
:discount_type => discount_type,
:discount_amount => discount_amount,
:discount_message => "#{discount_amount} #{discount_type} bundle discount!"
}]
if BUNDLE_ITEMS.empty? == false and BUNDLE_ITEMS.nil? == false
CAMPAIGNS = [
BundleDiscountCampaign.new(@BUNDLE_DISCOUNTS)
]
CAMPAIGNS.each do |campaign|
campaign.run(Input.cart)
end
end
end
Output.cart = Input.cart
Properties Exposed
Nosto implementation uses a private property field for sharing discount information with Shopify. In newer theme versions, Shopify automatically hides these fields while displaying products in cart page. In older version of themes, these fields gets exposed as shown below.
In such a case, make the following changes to the template liquid file that displays the cart information (usually cart.liquid or cart-template.liquid).
{% for p in item.properties %}
{% assign first_character_in_key = p.first | truncate: 1, '' %} <== new line
{% unless p.last == blank or first_character_in_key == '_' %} <== new line
<small>
{{ p.first }}:
{% comment %}
Check if there was an uploaded file associated
{% endcomment %}
{% if p.last contains '/uploads/' %}
<a href="{{ p.last }}">{{ p.last | split: '/' | last }}</a>
{% else %}
{{ p.last }}
{% endif %}
</small><br />
{% endunless %} <== new line
{% endfor %}
- 1.Nosto provided line item script is customized (No support provided).
- 2.SECRET_KEY value is incorrect.
- 3.Issue with Bundle script configuration.
- 4.Not all the products from a bundle are added to cart.
Contact Nosto support and share the line item script content for further analysis.
Last modified 1mo ago