vfsoraki
How to get current(or old?) value of field from an Ecto changeset?
I am currently using the following snippet to do it
old_value =
cs
|> Map.get(:data, %{})
|> Map.get(field, %{})
Is it the right way? I didn’t find a suitable function in Ecto docs, get_field gives the current change if it exists, but I want to get current(or old, not sure about the term) value, if there is a change or not.
Ecto version is 2.1.6.
Marked As Solved
josevalim
Yes, it is. But since you expect both the data field and the field itself to exist, you should do: changeset.data.name_of_the_field, as it will raise if you have a typo.
Also Liked
snofang
BTW, Referring to data in changeset without using Optimistic Locking is unreliable (except it is schema less or very special use case).
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