# Every

This alternative bundling strategy maximizes the number of items picked from the targeted group (listed according to the desired sorting logic) ensuring that it is equal to or a multiple of a specified number.

{% hint style="warning" %}
Bundles of type `every` can be created only from **one group** containing at least one item. If the related `actions.groups` array is made by more than one group, the Rule Engine will return an error. If the specified group is empty, the action won't be applied.
{% endhint %}

<table><thead><tr><th width="137">Key</th><th width="114">Type<select><option value="Djzo1UhBKQfW" label="Boolean" color="blue"></option><option value="VAIMp1rdLBI0" label="Integer" color="blue"></option><option value="qhaoRE82Rs3C" label="Float" color="blue"></option><option value="sk9tHN8WC8KO" label="String" color="blue"></option><option value="B3M67zaVXhvQ" label="Array" color="blue"></option><option value="MFocCrV7v0L6" label="Object" color="blue"></option></select></th><th width="114" data-type="checkbox">Required</th><th width="338">Notes</th></tr></thead><tbody><tr><td><strong><code>type</code></strong></td><td><span data-option="sk9tHN8WC8KO">String</span></td><td>true</td><td>Must be <code>"every"</code>.</td></tr><tr><td><strong><code>sort</code></strong></td><td><span data-option="MFocCrV7v0L6">Object</span></td><td>true</td><td>Learn more <a href="..#sort">here</a>.</td></tr><tr><td><strong><code>value</code></strong></td><td><span data-option="VAIMp1rdLBI0">Integer</span></td><td>true</td><td></td></tr></tbody></table>

## How the `every` algorithm works

1. The items of the targeted group are sorted according to the `sort.direction` function applied to the `sort.attribute` numeric field.
2. The total quantity of units within the group is calculated by adding up the quantities of each item: `Q = q1 + q2 + ... + qn`
3. Being `M` the maximum multiple of the number `V` specified in the bundle's `value` key that doesn't exceed the total quantity `Q`, the number of units that won't be discounted `X` is calculated by subtracting `M` from `Q`: `X = Q - M = Q mod V`
4. Starting from the bottom of the ordered list generated by the sorting, a quantity of units equal to `X` is removed to get the final list of items that will be discounted.

{% hint style="info" %}
If the number specified in the `value` key is already a multiple of the total quantity (i.e. `M = Q` and consequently `X = 0`), the action will be applied to all the items of the group.
{% endhint %}

{% hint style="warning" %}
If some items of the group match the bundle's `sort.direction` function with the same numeric value of the field specified in the `sort.attribute` value, they will be sorted as they are listed in the payload against which the rule is evaluated.
{% endhint %}

## Example

Let's assume that a rule's conditions define the `discountable-items` group of line items as follows:

<pre class="language-json"><code class="lang-json">[
  {
    "id": "qOYocnANsO",
    "type": "line_items",
<strong>    "quantity": 2,
</strong><strong>    "unit_amount_cents": 2000,
</strong>    "total_amount_cents": 4000,
    "sku": {
      "id": "PeHfayCvwQ",
<strong>      "code": "HAT"
</strong>    }
  },
  {
    "id": "nlHjpkVpCG",
    "type": "line_items",
<strong>    "quantity": 3,
</strong><strong>    "unit_amount_cents": 1000,
</strong>    "total_amount_cents": 3000,
    "sku": {
      "id": "pHaoUAvTVy",
<strong>      "code": "STICKER"
</strong>    }
  },
  {
    "id": "DtZjSMEKvm",
    "type": "line_items",
<strong>    "quantity": 2,
</strong><strong>    "unit_amount_cents": 3000,
</strong>    "total_amount_cents": 6000,
    "sku": {
      "id": "TkhHRotCOA",
<strong>      "code": "TSHIRT"
</strong>    }
  }
]
</code></pre>

Let's consider the following action that applies a 10% discount to the group above. The discount will be applied to bundles built by picking the items 2 at a time and prioritizing the ones with higher unit amounts:

<pre class="language-json"><code class="lang-json">"actions": [
  {
    "type": "percentage",
    "selector": "order.line_items.sku",
<strong>    "groups": [ "discountable-items" ],
</strong>    "bundle": {
<strong>      "type": "every",
</strong>      "sort": {
<strong>        "attribute": "unit_amount_cents",
</strong><strong>        "direction": "desc"
</strong>      }
<strong>      "value": 2
</strong>    },
    "value": 0.1
  }
]
</code></pre>

### 1. Sorting

The items of the group are sorted based on their unit amount, from the highest to the lowest:

<table><thead><tr><th>Item<select><option value="VSoeYxLP5ogG" label="TSHIRT" color="blue"></option><option value="pgdBGI5a7Lib" label="HAT" color="blue"></option><option value="iMO3gKoox4L8" label="STICKER" color="blue"></option></select></th><th data-type="number">Quantity</th><th>Unit amount</th></tr></thead><tbody><tr><td><span data-option="VSoeYxLP5ogG">TSHIRT</span></td><td>2</td><td>3000</td></tr><tr><td><span data-option="pgdBGI5a7Lib">HAT</span></td><td>2</td><td>2000</td></tr><tr><td><span data-option="iMO3gKoox4L8">STICKER</span></td><td>3</td><td>1000</td></tr></tbody></table>

### 2. Total quantity of units

The total quantity of units within the group is `Q = 2 + 3 + 2 = 7`.

### 3. Number of units to be removed

Being the number of the `bundle.value` key `2`, the number of units to be removed is calculated as the remainder of the division between the total quantity and the value: `7 mod 2 = 1`.

### 4. Items to be discounted

One item will be removed starting from the bottom of the [ordered list](#id-1.-sorting) (i.e. one sticker), thus getting to the final outcome, resulting in a 10% discount applied to 2x bundles, not to the additional item with lower unit price:

<table><thead><tr><th>SKU<select><option value="VSoeYxLP5ogG" label="TSHIRT" color="blue"></option><option value="pgdBGI5a7Lib" label="HAT" color="blue"></option><option value="iMO3gKoox4L8" label="STICKER" color="blue"></option></select></th><th data-type="number">Quantity</th><th>Discounted unit amount</th></tr></thead><tbody><tr><td><span data-option="VSoeYxLP5ogG">TSHIRT</span></td><td>2</td><td>5400</td></tr><tr><td><span data-option="pgdBGI5a7Lib">HAT</span></td><td>2</td><td>3600</td></tr><tr><td><span data-option="iMO3gKoox4L8">STICKER</span></td><td>2</td><td>1800</td></tr></tbody></table>