# Phase 12.2: Admin form fields: date, file upload, relation editing with deferred binding - Discussion Log

> **Audit trail only.** Do not use as input to planning, research, or execution agents.
> Decisions are captured in CONTEXT.md — this log preserves the alternatives considered.

**Date:** 2026-10-02
**Phase:** 12.2-admin-form-fields-date-file-upload-relation-editing-with-def
**Areas discussed:** Deferred binding mechanics, Fileupload contract, Relation child CRUD, Datepicker semantics

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## Deferred binding mechanics

| Question | Options | Selected |
|----------|---------|----------|
| Storage | Winter's deferred_bindings (+ owner admin id) / Go-native table | Winter's deferred_bindings |
| Session key | SPA random key bound to admin / server-issued signed key / Winter-exact unbound | SPA random key, bound to admin |
| When defer | Winter split (uploads always deferred, relation changes only on unsaved) / unsaved only / always deferred | Winter split |
| Purge | River periodic + command, 5 days / command only | River periodic + command |

## Fileupload contract

| Question | Options | Selected |
|----------|---------|----------|
| Declare | Model interface `AttachRelations()` / typed struct fields | Model interface |
| Helper | Public attach helper / cabana-private | Public attach helper |
| Keys | Practical set (mode, fileTypes, mimeTypes, maxFilesize, maxFiles, imageWidth/Height, thumbOptions, useCaption, prompt) / minimal | Practical set |
| Protected | Support public and protected / public only | Support both |

## Relation child CRUD

| Question | Options | Selected |
|----------|---------|----------|
| Child form | config_relation `manage.form` / related model's default fields.yaml | manage.form |
| Buttons | Winter toolbarButtons (create, update, delete, link, unlink) / create-edit-delete only for hasMany | Winter toolbarButtons |
| Pivot | `pivot.form` support / related record only | pivot.form support |
| Nesting | Full form with own session key / simple fields only | Full form, own session key |

## Datepicker semantics

| Question | Options | Selected |
|----------|---------|----------|
| Timezone | UTC store, browser tz edit / one backend.timezone config | UTC store, browser tz edit |
| Go types | time.Time + lagoon.Date / lagoon.TimeOfDay / time.Time for everything | time.Time + lagoon types |
| Keys | Practical set (mode, format, minDate, maxDate, yearRange, firstDay, twelveHour, ignoreTimezone) / minimal | Practical set |
| Picker UI | Reka UI DatePicker / native inputs | Reka UI DatePicker |

## Todos

Matcher flagged four todos (benchmark, nest packages, admin API tokens, bonfire duplicate commands) on keyword overlap only. User chose to fold none.

## Claude's Discretion

Route names, session-key transport, attach API shapes, thumb sizes, date/time list columns, purge config keys, plan split.

## Deferred Ideas

Image cropping; nested relation manager in a child modal; migrating fonoteka.go uploads onto the new attach helper.