migratetest

Documentation

Overview

Package migratetest is the shared regression harness for one production bug class: a store's migrate() creates an index over a column that a pre-existing (legacy) table lacks — because the column is ALTER-added later — so CREATE INDEX fails "no such column", migrate() fails, mount fails, and the pod crashloops on deploy.

A Case seeds one store's REAL pre-migration schema into a fresh database, then runs that store's REAL open+migrate over it and asserts it succeeds and is idempotent — proving migration-correctness as a pure test over schema epochs instead of discovering it at production boot. Because each clients/* store's migrate() is unexported, the store's own package wires the Open closure; the assertion lives here, once, so every store shares ONE correctness check.

Index

• type Case
  • func (c Case) Run(t *testing.T)

Types

type Case

type Case struct {
	Name      string
	LegacyDDL string
	Open      func(dir string) (io.Closer, error)
	Probe     func(t *testing.T, store io.Closer)
}

Case is one store's legacy-schema migration regression.

• Name is the store's SUBSYSTEM — what names its database, and so the failure label too. It must be the store's own name, because the harness seeds the legacy schema into the SAME database Open then opens.
• LegacyDDL is the store's table(s) EXACTLY as a pre-migration production DB carries them — i.e. WITHOUT the columns the store later ALTER-adds. This is the shape over which an index-before-column ordering bug fails.
• Open opens a store under dir and runs its migrate() (the caller's package-local openStore), returning the store as an io.Closer. It is called AFTER the harness seeds LegacyDDL into that same database, so it exercises the exact boot path that crashloops on a legacy DB.
• Probe, if set, runs one write after a successful migrate to prove the forward-added columns (and their now-safe indexes) are usable.

func (Case) Run

func (c Case) Run(t *testing.T)

Run seeds LegacyDDL, migrates over it, optionally probes, then re-opens to prove migrate() is idempotent (a warm restart must not fail).