Look up before writing
The member is fetched first and the router decides what happens next. The update and the log sit behind the member-found filter, so a mistyped email cannot create or alter a record.
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AI and automation / 2026
Gym Subscription Renewal Workflow
A membership renewal is several linked updates: find the member, set the plan, mark them active, work out the new expiry date and keep a record that it happened. Done by hand, one of them gets missed.
The assignment was to update a member's Airtable record once a subscription is renewed. The scenario takes an email, a plan and an amount by webhook, looks the member up through the Airtable API, and branches. A found member is updated and a row is added to a separate renewals table. An unknown email gets a 404 response that says why, and nothing is changed. The new expiry date is computed inside the update from the plan.
- Role
- Workflow builder
- For
- TS Academy coursework
- Stage
- Course project
Walkthrough
Watch it run
Built from the assignment recording: the scenario, the expiry rule, a renewal request and its response, the run log, and an unknown member that is rejected without changing anything.
My part
What I built
- Built the scenario: webhook, Airtable lookup, router, member update, renewal log and both responses.
- Called the Airtable REST API directly for the lookup, update and insert.
- Wrote the expiry expression and the fallback to the member's existing plan.
- Designed the success and not-found response bodies.
- Tested both outcomes with cURL and checked the tables and run history.
Decisions
The choices that shaped it
The plan decides the dates
The caller sends a plan, not a date. The update computes the expiry as today plus 365 days for annual, 90 for quarterly and 30 otherwise, so two callers cannot disagree about what a plan means.
History in its own table
The member row holds only the current state. Each renewal also adds a row to a separate table, so earlier renewals are not lost when the member is updated again.
Errors another system can read
The not-found path returns a 404 status, an error code and a plain message. A caller can branch on the code without parsing the text.
What has been shown to work
- An annual renewal for a sample member returned an Active status, a start date of 2026-05-23 and an expiry of 2027-05-23, with a renewal log ID.
- A monthly renewal for the same member moved the expiry to 2026-06-22.
- The Members table and the Renewals table showed the new values in the recording.
- A request for an unknown email returned ok: false and member_not_found. The run history shows the update step filtered out.
Current stage and limits
- This is a course assignment, not a system a gym uses.
- The amount is request data. No payment is collected or verified.
- There is no signature check or duplicate protection: sending the same request twice logs two renewals.
- A renewal always starts today. It does not extend from the current expiry date.
Screens
From the product
Technical detailOpen the system view
SYSTEM ARCHITECTURE
Gym Renewal Workflow system view
The assignment was to update a member's Airtable record once a subscription is renewed. The scenario takes an email, a plan and an amount by webhook, looks the member up through the Airtable API, and branches. A found member is updated and a row is added to a separate renewals table. An unknown email gets a 404 response that says why, and nothing is changed. The new expiry date is computed inside the update from the plan.A webhook accepts a JSON body with the member's email, the plan and the amount.
An Airtable API call searches the Members table by email, ignoring letter case, and returns at most one record.
A router sends the request down a member-found or member-not-found route.
Found: a PATCH sets status to Active and writes the plan, start date, expiry date and last-renewed date.
A POST then adds a row to the Renewals table with the plan, amount and date.
- 01Input / actorconnects toInterface
- 02Interfaceconnects toCore service
- 03Core serviceconnects toOperational boundary
- 04Operational boundaryconnects toState / outcome
Security and privacy
- The member is a sample record with an example.com address.
- The webhook address and Airtable base identifiers are cropped out of the published captures.
Built with
Work with me
I build workflows like this one as a fixed-price service: one defined, tested n8n or Make.com workflow, with packages from $149.
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