36 lines
1.2 KiB
Ruby
36 lines
1.2 KiB
Ruby
# references:
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# https://evilmartians.com/chronicles/active-storage-meets-graphql-pt-2-exposing-attachment-urls
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module Extensions
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class Attachment < GraphQL::Schema::FieldExtension
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attr_reader :attachment_assoc
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def apply
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# Here we try to define the attachment name:
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# - it could be set explicitly via extension options
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# - or we imply that is the same as the field name w/o "_url"
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# suffix (e.g., "avatar_url" => "avatar")
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attachment = options&.[](:attachment) || field.original_name.to_s.sub(/_url$/, "")
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# that's the name of the Active Record association
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@attachment_assoc = "#{attachment}_attachment"
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end
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# This method resolves (as it states) the field itself
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# (it's the same as defining a method within a type)
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def resolve(object:, **_rest)
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Loaders::Association.for(
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object.object.class,
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attachment_assoc => :blob
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).load(object.object)
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end
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# This method is called if the result of the `resolve`
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# is a lazy value (e.g., a Promise – like in our case)
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def after_resolve(value:, **_rest)
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return if value.nil?
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Rails.application.routes.url_helpers.url_for(value)
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end
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end
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end
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