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… mess up the configuration collection.
| return &database.Error{OrigErr: err, Err: "save version failed"} | ||
| filt := bson.D{{"version", bson.D{{"$exists", true}}}} | ||
| upd := bson.D{{"$set", bson.D{ | ||
| {"version", int32(version)}, |
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| {"dirty", dirty}, | ||
| }}} | ||
| var tr = true | ||
| if res := migrationsCollection.FindOneAndUpdate(context.TODO(), filt, upd, &options.FindOneAndUpdateOptions{Upsert: &tr}); res.Err() != nil { |
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dhui
Sep 9, 2019
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You'll probably run into fewer races with FindOneAndUpdate() + Upsert: true than Drop() + InsertOne(), but this change won't actually make it safe to run migrations concurrently. e.g. it doesn't serialize/coordinate changes
To run safely concurrently, you'll need to use transactions. This isn't a blocker for merging this PR, but as is, the release notes would only state that a race condition is less likely to happen.
|
Also, tests (linter) are failing: |
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mrqzzz commentedSep 5, 2019
SetVersion in mongodb.go is now atomical.
Concurrent migrations don't mess up the configuration collection.