cmd/seed: synthetic dataset for local development#70
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Add a deterministic ~6-month synthetic dataset (~9.8k rows, gentle sinusoid with occasional spikes and quiet days) for exercising the dashboard locally without needing real production exports. The generator deliberately spans every period (7d / 30d / 3m / 6m / 1y) so the chart UI has data to render at any range. Safety properties: - Refuses to run unless Config.Environment == "development". - INSERT … ON CONFLICT (id) DO NOTHING, so re-running is a no-op. - Steam IDs use a clearly-synthetic 76561198000000000 prefix. - Snowflake IDs encode the same created_at + sequence layout as the production generator, so synthetic rows sort chronologically alongside any real rows already in the DB. internal-docs/ and internal/devseed/fixtures/ are added to .gitignore to keep author scratch space and any future local CSV fixtures out of the public repo. Co-authored-by: Cursor <cursoragent@cursor.com>
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| const ( | ||
| syntheticRNGSeed int64 = 42 | ||
| syntheticDays = 180 | ||
| syntheticTargetTotal = 9800 |
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Specify the datatype here.
Also, we probably don't need 9800 entries, a couple thousand should work.
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Done — syntheticTargetTotal int = 2000.
| // days). Snowflake IDs are unique within the slice and won't collide with | ||
| // real CSV-seeded IDs, so callers can pipe the result straight into | ||
| // InsertReversals. | ||
| func GenerateSynthetic(now time.Time) []*models.Reversal { |
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Let's normalize now() to UTC before we derive any dates.
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Done — now() is normalized to UTC before any dates are derived.
| The seed: | ||
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| - Refuses to run unless `Environment` is `development`. | ||
| - Uses `INSERT … ON CONFLICT (id) DO NOTHING`, so it's safe to re-run. | ||
| - Generates a deterministic 6-month dataset so the dashboard at `/` has enough data to exercise every period (7d / 30d / 3m / 6m / 1y). | ||
| - Uses a synthetic Steam ID prefix (`76561198000000000`) so generated IDs are clearly fake. |
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You can just state that this must be ran in a development environment. Also, please move this to the end of the README.
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Done — simplified to "must be run in a development environment" and moved the section to the end of the README.
- Give syntheticTargetTotal an explicit int type and reduce the seed to ~2,000 rows (a couple thousand) for faster local seeding. - Normalize the incoming now to UTC before deriving any dates so the generated series is timezone-independent. - Simplify the README seeding guard to "must be run in a development environment", move the seeding section to the end of the README, and stop claiming idempotency (reruns add more data since IDs derive from wall-clock time). Co-authored-by: Cursor <cursoragent@cursor.com>
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Cursor Bugbot has reviewed your changes using default effort and found 2 potential issues.
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Reviewed by Cursor Bugbot for commit c4d8523. Configure here.
Re-running the seed on a different day produces new snowflake IDs but the same deterministic (steam_id, marketplace_slug) pairs, which collide with the partial unique index idx_reversals_steam_id_marketplace_slug. Target that natural key (with the WHERE deleted_at IS NULL predicate) in the ON CONFLICT DO NOTHING clause so reruns skip existing rows instead of raising a unique-constraint error, and correct the README/doc comments to describe the idempotent behavior. Also clamp the synthetic createdAt to models.Epoch before the unsigned snowflake timestamp subtraction so an out-of-range clock can't underflow into a garbage ID.
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Summary
Add a deterministic ~6-month synthetic dataset (~9.8k rows, gentle sinusoid with occasional spikes and quiet days) for exercising the dashboard locally without needing a real production export. The generator deliberately spans every period the chart picker offers (7d / 30d / 3m / 6m / 1y), so any range renders meaningful data.
Safety properties
.gitignore
Adds `internal-docs/` (author scratch space) and `internal/devseed/fixtures/` (room for any future local-only CSV fixtures) so neither leaks into the public repo.
Test plan
Made with Cursor
Note
Low Risk
Dev-only CLI with an environment guard and idempotent inserts; not linked to the production server binary.
Overview
Adds a dev-only seed path so local Postgres can hold a deterministic ~6-month reversal history (~9.8k rows) without production exports.
go run ./cmd/seedloads config, exits unlessEnvironmentisdevelopment, then bulk-inserts generated rows into the public DB viaON CONFLICT (id) DO NOTHING(safe to re-run).internal/devseedbuilds daily volume with variance, marketplace mix, sources, optional expungements, synthetic Steam IDs, and snowflake IDs aligned with production ordering.README documents the workflow and dashboard period coverage;
.gitignoreexcludesinternal-docs/and optionalinternal/devseed/fixtures/.Reviewed by Cursor Bugbot for commit b067b6b. Bugbot is set up for automated code reviews on this repo. Configure here.