zrepl/platformtest/tests/idempotentDestroy.go
Christian Schwarz b33f670b9d [#316] endpoint / replication protocol: more robust step-holds and replication cursor management
- drop HintMostRecentCommonAncestor rpc call
    - it is wrong to put faith into the active side of the replication to always make that call
      (we might not trust it, ref pull setup)
- clean up step holds + step bookmarks + replication cursor bookmarks on
  send RPC instead
    - this makes it symmetric with Receive RPC
- use a cache (endpoint.sendAbstractionsCache) to avoid the cost of
  listing the on-disk endpoint abstractions state on every step

The "create" methods for endpoint abstractions (CreateReplicationCursor, HoldStep) are now fully
idempotent and return an Abstraction.

Notes about endpoint.sendAbstractionsCache:
- fills lazily from disk state on first `Get` operation
- fill from disk is generally only attempted once
    - unless the `ListAbstractions` fails, in which case the fill from
      disk is retried on next `Get` (the current `Get` will observe a
      subset of the actual on-disk abstractions)
    - the `Invalidate` method is called
- it is a global (zrepl process-wide) cache

fixes #316
2020-05-19 11:30:02 +02:00

76 lines
1.6 KiB
Go

package tests
import (
"fmt"
"log"
"github.com/zrepl/zrepl/platformtest"
"github.com/zrepl/zrepl/zfs"
)
func IdempotentDestroy(ctx *platformtest.Context) {
platformtest.Run(ctx, platformtest.PanicErr, ctx.RootDataset, `
DESTROYROOT
CREATEROOT
+ "foo bar"
+ "foo bar@a snap"
`)
fs := fmt.Sprintf("%s/foo bar", ctx.RootDataset)
asnap := fsversion(ctx, fs, "@a snap")
_, err := zfs.ZFSBookmark(ctx, fs, asnap, "a bookmark")
if err != nil {
panic(err)
}
type testCase struct {
description, path string
}
cases := []testCase{
{"snapshot", fmt.Sprintf("%s@a snap", fs)},
{"bookmark", fmt.Sprintf("%s#a bookmark", fs)},
{"filesystem", fs},
}
for i := range cases {
func() {
c := cases[i]
log.Printf("SUBBEGIN testing idempotent destroy %q for path %q", c.description, c.path)
log.Println("destroy existing")
err = zfs.ZFSDestroy(ctx, c.path)
if err != nil {
panic(err)
}
log.Println("destroy again, non-idempotently, must error")
err = zfs.ZFSDestroy(ctx, c.path)
if _, ok := err.(*zfs.DatasetDoesNotExist); !ok {
panic(fmt.Sprintf("%T: %s", err, err))
}
log.Println("destroy again, idempotently, must not error")
err = zfs.ZFSDestroyIdempotent(ctx, c.path)
if err != nil {
panic(err)
}
log.Println("SUBEND")
}()
}
// also test idempotent destroy for cases where the parent dataset does not exist
err = zfs.ZFSDestroyIdempotent(ctx, fmt.Sprintf("%s/not foo bar@nonexistent snapshot", ctx.RootDataset))
if err != nil {
panic(err)
}
err = zfs.ZFSDestroyIdempotent(ctx, fmt.Sprintf("%s/not foo bar#nonexistent bookmark", ctx.RootDataset))
if err != nil {
panic(err)
}
}