Mechanic is a development and ecommerce automation platform for Shopify. :)
The collection update webhook does not fire when product memberships change based on the smart collection's rules. This task bridges that gap by monitoring smart collections at regular intervals to see if the list of their product IDs has changed, and if so it will trigger the custom event topic you configure.
Runs Occurs every hour and Occurs when a user manually triggers the task. Configuration includes run frequency, custom event topic, collections to monitor, and extra logging.
The collection update webhook does not fire when product memberships change based on the smart collection's rules. This task bridges that gap by monitoring smart collections at regular intervals to see if the list of their product IDs has changed, and if so it will trigger the custom event topic you configure.
Choose to have the task run in intervals of 10min, 15min, 20min, 30min, hourly, or daily. Optionally, pick specific collections to monitor. If no collections are configured, then this task will monitor all smart collections in the shop.
Example use case:
A 3rd party app/integration/service has a feature to sync a collection's products to their platform. However, it depends on the collection update webhook to know when products should be re-synced. Since this will not happen for a smart collection solely when product memberships change, a task could be developed to listen for the configured custom event, and then either interface with that service's API directly to trigger a sync, or perhaps simply add a new tag to the collection to trigger the update webhook.
Notes:
- The custom event topic must follow the Mechanic naming convention for user-defined topics
- The task will only send along the collection's global ID in a collection_id variable to the custom event
- A custom event will be triggered for each qualifying collection
- This task will not send a custom event for newly seen smart collections, since it has to first save a hashed list of product IDs in a collection metafield
- The "Extra logging" option is there if you would like to see log messages for empty collections and collections that have not changed. Leave it unchecked unless debugging to keep the frequent task run logs nice and tidy.
Mechanic is designed to benefit everybody: merchants, customers, developers, agencies, Shopifolks, 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.
(By the way, have you seen our documentation? Have you joined the Slack community?)
mechanic/scheduler/{{ options.run_frequency__select_o1_10min_o2_15min_o3_20min_o4_30min_o5_hourly_o6_daily_required }}
mechanic/user/trigger{% assign run_frequency = options.run_frequency__select_o1_10min_o2_15min_o3_20min_o4_30min_o5_hourly_o6_daily_required %}
{% assign custom_event_topic = options.custom_event_topic__required %}
{% assign collections_to_monitor = options.collections_to_monitor__picker_collection_array %}
{% assign extra_logging = options.extra_logging__boolean %}
{% if collections_to_monitor == blank or event.preview %}
{% comment %}
-- get IDs for all smart collections in shop
-- note: Shopify has a limit of 5000 smart collections per shop
{% endcomment %}
{% assign cursor = nil %}
{% assign collection_ids = array %}
{% for n in (1..20) %}
{% capture query %}
query {
collections(
first: 250
after: {{ cursor | json }}
query: "collection_type:smart"
) {
pageInfo {
hasNextPage
endCursor
}
nodes {
id
}
}
}
{% endcapture %}
{% assign result = query | shopify %}
{% if event.preview %}
{% capture result_json %}
{
"data": {
"collections": {
"nodes": [
{
"id": "gid://shopify/Collection/1234567890"
}
]
}
}
}
{% endcapture %}
{% assign result = result_json | parse_json %}
{% endif %}
{% assign collection_ids
= result.data.collections.nodes
| map: "id"
| concat: collection_ids
%}
{% if result.data.collections.pageInfo.hasNextPage %}
{% assign cursor = result.data.collections.pageInfo.endCursor %}
{% else %}
{% break %}
{% endif %}
{% endfor %}
{% else %}
{% comment %}
-- add all configured collections to IDs array, but check each one later to make sure it is a smart collection
{% endcomment %}
{% assign collection_ids = collections_to_monitor %}
{% endif %}
{% comment %}
-- process each collection
{% endcomment %}
{% for collection_id in collection_ids %}
{% comment %}
-- make sure collection type is smart
-- get saved hash of sorted product IDs from collection metafield
-- get sorted product IDs in collection (up to 25K)
{% endcomment %}
{% assign cursor = nil %}
{% assign product_ids = array %}
{% for n in (1..100) %}
{% capture query %}
query {
collection(id: {{ collection_id | json }}) {
title
ruleSet {
__typename
}
metafield(key: "mechanic.product_ids_hash") {
value
}
products(
first: 250
after: {{ cursor | json }}
sortKey: ID
) {
pageInfo {
hasNextPage
endCursor
}
nodes {
id
}
}
}
}
{% endcapture %}
{% assign result = query | shopify %}
{% if event.preview %}
{% capture result_json %}
{
"data": {
"collection": {
"ruleSet": {
"__typename": "CollectionRuleSet"
},
"metafield": {
"value": "n0t5r35lh5sh"
},
"products": {
"nodes": [
{
"id": "gid://shopify/Product/1234567890"
}
]
}
}
}
}
{% endcapture %}
{% assign result = result_json | parse_json %}
{% endif %}
{% assign collection = result.data.collection | except: "products" %}
{% assign batch_product_ids = result.data.collection.products.nodes | map: "id" %}
{% assign product_ids = product_ids | concat: batch_product_ids %}
{% if result.data.collection.products.pageInfo.hasNextPage %}
{% assign cursor = result.data.collection.products.pageInfo.endCursor %}
{% else %}
{% break %}
{% endif %}
{% endfor %}
{% comment %}
-- check for smart collection in case these collections were configured manually in the task
{% endcomment %}
{% if collection.ruleSet == blank %}
{% log
message: "This collection is not smart collection.",
collection: collection.title,
collection_id: collection_id
%}
{% continue %}
{% endif %}
{% if product_ids == blank and collection.metafield.value == blank %}
{% if extra_logging %}
{% log
message: "This collection has no products and no previously saved metafield value; skipping.",
collection: collection.title,
collection_id: collection_id
%}
{% endif %}
{% continue %}
{% endif %}
{% assign product_ids_hash = product_ids | md5 %}
{% if product_ids_hash == collection.metafield.value %}
{% if extra_logging %}
{% log
message: "This collection's products match the previously saved metafield value; nothing to do.",
collection: collection.title,
collection_id: collection_id
%}
{% endif %}
{% continue %}
{% endif %}
{% comment %}
-- set collection metafield
{% endcomment %}
{% action "shopify" %}
mutation {
metafieldsSet(
metafields: [
{
ownerId: {{ collection_id | json }},
namespace: "mechanic"
key: "product_ids_hash"
type: "single_line_text_field"
value: {{ product_ids_hash | json }}
}
]
) {
metafields {
id
namespace
key
type
value
owner {
... on Collection {
id
title
}
}
}
userErrors {
code
field
message
}
}
}
{% endaction %}
{% comment %}
-- fire custom event if there was a previously saved metafield value
{% endcomment %}
{% if collection.metafield.value != blank %}
{% action "event" %}
{
"topic": {{ custom_event_topic | json }},
"data": {
"collection_id": {{ collection_id | json }}
}
}
{% endaction %}
{% endif %}
{% endfor %}hourly
user/smart_collection/product_membership_changed