Mechanic is a development platform for Shopify. :)
Use this task to automatically sync inventory for a simple product bundle – no theme modifications required. When configured with unique SKUs for the bundle and its components, this task keeps the bundle inventory equal to the lowest inventory level of its component products, and appropriately subtracts from component inventory whenever the bundle is ordered. When a bundle order is refunded, the components are raised back up, appropriately.
Runs when an order is created, when a refund is created, when an inventory level is updated, and when a user triggers the task. Configuration includes bundle product sku, component product skus, and inventory buffer quantity.
Usage:
Requirements:
Notes:
Mechanic is designed to benefit everybody: merchants, customers, developers, agencies, Gurus, everybody.
That’s why we make it easy to configure automation without code, why we make it easy to tweak the underlying code once tasks are installed, and why we publish it all here for everyone to learn from.
{% assign bundle_sku = options.bundle_product_sku__required %}
{% assign component_skus = options.component_product_skus__array_required %}
{% assign all_skus = component_skus | join: "|||" | prepend: "|||" | prepend: bundle_sku | split: "|||" %}
{% if component_skus.size > 249 %}
{% error %}
{{ "This task only supports up to 249 component product SKUs. You've added " | append: component_skus.size | append: "." | json }}
{% enderror %}
{% endif %}
{% assign do_full_sync = false %}
{% assign do_component_adjustment = false %}
{% assign component_adjustment_quantity = nil %}
{% if event.topic == "mechanic/user/trigger" %}
{% assign do_full_sync = true %}
{% endif %}
{% if event.topic == "shopify/orders/create" %}
{% if event.preview %}
{% capture order_json %}
{
"line_items": [
{
"sku": {{ bundle_sku | json }},
"quantity": 1
}
]
}
{% endcapture %}
{% assign order = order_json | parse_json %}
{% endif %}
{% assign bundle_quantity = order.line_items | where: "sku", bundle_sku | map: "quantity" | sum %}
{% if bundle_quantity != 0 %}
{% assign do_component_adjustment = true %}
{% assign component_adjustment_quantity = bundle_quantity | times: -1 %}
{% endif %}
{% endif %}
{% if event.topic == "shopify/refunds/create" %}
{% if event.preview %}
{% capture refund_json %}
{
"refund_line_items": [
{
"quantity": 1,
"restock_type": "cancel",
"line_item": {
"quantity": 1,
"sku": {{ bundle_sku | json }}
}
}
]
}
{% endcapture %}
{% assign refund = refund_json | parse_json %}
{% endif %}
{% assign bundle_restock_quantity = 0 %}
{% for refund_line_item in refund.refund_line_items %}
{% if refund_line_item.line_item.sku == bundle_sku and refund_line_item.restock_type != "no_restock" %}
{% assign do_component_adjustment = true %}
{% assign bundle_restock_quantity = bundle_restock_quantity | plus: refund_line_item.quantity %}
{% endif %}
{% endfor %}
{% assign component_adjustment_quantity = bundle_restock_quantity %}
{% endif %}
{% if event.topic contains "shopify/inventory_levels/" %}
{% comment %}
Note: we don't use the "available" figure that comes in with this payload,
to guard against receiving webhooks in the wrong order, or a delay in event
processing.
{% endcomment %}
{% capture query %}
query {
inventoryLevel(id: {{ inventory_level.admin_graphql_api_id | json }}) {
item {
variant {
sku
}
}
}
}
{% endcapture %}
{% assign result = query | shopify %}
{% if event.preview %}
{% capture result_json %}
{
"data": {
"inventoryLevel": {
"item": {
"variant": {
"sku": {{ component_skus.first | json }}
}
}
}
}
}
{% endcapture %}
{% assign result = result_json | parse_json %}
{% endif %}
{% assign updated_sku = result.data.inventoryLevel.item.variant.sku %}
{% if all_skus contains updated_sku %}
{% assign do_full_sync = true %}
{% else %}
{% log %}
{{ updated_sku | json | prepend: "Inventory was updated for SKU " | append: ", which is not related to this bundle." | json }}
{% endlog %}
{% endif %}
{% endif %}
{% if do_component_adjustment %}
{% assign query_components = array %}
{% for sku in component_skus %}
{% assign query_components[query_components.size] = sku | json | prepend: "sku:" %}
{% endfor %}
{% capture query %}
query {
productVariants(
first: {{ component_skus.size | json }}
query: {{ query_components | join: " OR " | json }}
) {
edges {
node {
inventoryItem {
inventoryLevels(first: 1) {
edges {
node {
id
}
}
}
}
sku
}
}
}
}
{% endcapture %}
{% assign result = query | shopify %}
{% if event.preview %}
{% capture result_json %}
{
"data": {
"productVariants": {
"edges": [
{% for sku in component_skus %}
{
"node": {
"inventoryItem": {
"inventoryLevels": {
"edges": [
{
"node": {
"id": "gid://shopify/InventoryLevel/1234567890?inventory_item_id=1234567890"
}
}
]
}
},
"sku": {{ sku | json }}
}
}
{% unless forloop.last %},{% endunless %}
{% endfor %}
]
}
}
}
{% endcapture %}
{% assign result = result_json | parse_json %}
{% endif %}
{% assign variants = result.data.productVariants.edges | map: "node" %}
{% assign found_skus = variants | map: "sku" | uniq %}
{% if variants.size != component_skus.size or found_skus.size != variants.size %}
{% error %}
{{ "Expected to find " | append: component_skus.size | append: " matching component product variants with unique SKUs, based on the task configuration, but found " | append: variants.size | append: " matching variants with " | append: found_skus.size | append: " unique SKUs instead. Make sure each SKU for this task only has one associated product in your store." | json }}
{% enderror %}
{% endif %}
{% action "shopify" %}
mutation {
{% for variant in variants %}
inventoryAdjustQuantity{{ forloop.index }}: inventoryAdjustQuantity(
input: {
inventoryLevelId: {{ variant.inventoryItem.inventoryLevels.edges.first.node.id | json }}
availableDelta: {{ component_adjustment_quantity | json }}
}
) {
inventoryLevel {
id
available
item {
variant {
sku
}
}
}
userErrors {
field
message
}
}
{% endfor %}
}
{% endaction %}
{% endif %}
{% if do_full_sync %}
{% assign query_components = array %}
{% for sku in all_skus %}
{% assign query_components[query_components.size] = sku | json | prepend: "sku:" %}
{% endfor %}
{% capture query %}
query {
productVariants(
first: {{ all_skus.size | json }}
query: {{ query_components | join: " OR " | json }}
) {
edges {
node {
inventoryQuantity
inventoryItem {
inventoryLevels(first: 1) {
edges {
node {
id
}
}
}
}
sku
}
}
}
}
{% endcapture %}
{% assign result = query | shopify %}
{% if event.preview %}
{% capture result_json %}
{
"data": {
"productVariants": {
"edges": [
{
"node": {
"inventoryItem": {
"inventoryLevels": {
"edges": [
{
"node": {
"id": "gid://shopify/InventoryLevel/1234567890?inventory_item_id=1234567890"
}
}
]
}
},
"inventoryQuantity": 2,
"sku": {{ bundle_sku | json }}
}
},
{% for sku in component_skus %}
{
"node": {
"inventoryItem": {
"inventoryLevels": {
"edges": [
{
"node": {
"id": "gid://shopify/InventoryLevel/1234567890?inventory_item_id=1234567890"
}
}
]
}
},
"inventoryQuantity": 1,
"sku": {{ sku | json }}
}
}
{% unless forloop.last %},{% endunless %}
{% endfor %}
]
}
}
}
{% endcapture %}
{% assign result = result_json | parse_json %}
{% endif %}
{% assign variants = result.data.productVariants.edges | map: "node" %}
{% assign found_skus = variants | map: "sku" | uniq %}
{% if variants.size != all_skus.size or found_skus.size != variants.size %}
{% error %}
{{ "Expected to find " | append: all_skus.size | append: " matching component product variants with unique SKUs, based on the task configuration, but found " | append: variants.size | append: " matching variants with " | append: found_skus.size | append: " unique SKUs instead. Make sure each SKU for this task only has one associated product in your store." | json }}
{% enderror %}
{% endif %}
{% assign minimum_inventory_variant = nil %}
{% assign bundle_variant = nil %}
{% for variant in variants %}
{% if variant.sku == bundle_sku %}
{% assign bundle_variant = variant %}
{% elsif component_skus contains variant.sku %}
{% if minimum_inventory_variant == nil or minimum_inventory_variant.inventoryQuantity > variant.inventoryQuantity %}
{% assign minimum_inventory_variant = variant %}
{% endif %}
{% endif %}
{% endfor %}
{% assign delta = minimum_inventory_variant.inventoryQuantity | minus: bundle_variant.inventoryQuantity %}
{% if options.inventory_buffer_quantity__number != blank %}
{% assign delta = delta | minus: options.inventory_buffer_quantity__number %}
{% endif %}
{% if delta != 0 %}
{% action "shopify" %}
mutation {
inventoryAdjustQuantity(
input: {
inventoryLevelId: {{ bundle_variant.inventoryItem.inventoryLevels.edges.first.node.id | json }}
availableDelta: {{ delta | json }}
}
) {
inventoryLevel {
id
available
item {
variant {
sku
}
}
}
userErrors {
field
message
}
}
}
{% endaction %}
{% endif %}
{% endif %}