Ecto Custom Field Setting

Elixir Snippet: How to set a custom field in ecto changeset pipelines based on previous data fields.

# declare this in your schema file
defp slugify(changeset, from_field, to_field, options \\ []) do
  case Map.get(changeset.changes, from_field) do
    nil -> changeset
    str -> put_change(changeset, to_field, Slug.slugify(str, options))

# use it like this
# ...
|> slugify(:name, :slug)
# ...

Instead of passing everything as attrs from the outside, you can modify data fields during changeset casting. In this example, the slugify library is used to automatically generate a slug field from a name field, but only if the changeset wants to actually change the name field.

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A toolkit for data mapping and language integrated query. The Elixir answer to Ruby's ActiveRecord.

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Harness the power of concurrent, fault-tolerant programming for scalable, maintainable applications. Code that flows like water!

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Data Engineering

Explore the essentials of Data Engineering, delving into how data systems are built and maintained. From organizing data flows to automating complex data processes, discover the tools and techniques that make data easily accessible and useful for everyday projects and insights.