Module: ActiveStorage::AsyncVariants::Helper

Included in:
AssetTagHelperExtension
Defined in:
lib/active_storage/async_variants/helper.rb

Overview

View/controller helper methods. Included in the AssetTagHelperExtension (so image_tag/video_tag can use them) and added to StatesController via ‘helper ActiveStorage::AsyncVariants::Helper` (so the state partials can use them).

Constant Summary collapse

PLACEHOLDER_SRC =

1x1 transparent GIF: reserves the variant’s box without fetching the original through the representations path on every poll.

"data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7"

Instance Method Summary collapse

Instance Method Details

#async_variant_box_dimensions(variant) ⇒ Object 



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# File 'lib/active_storage/async_variants/helper.rb', line 22

def async_variant_box_dimensions(variant)
  resize = variant.variation.transformations
    .values_at(:resize_to_limit, :resize_to_fit, :resize_to_fill)
    .compact.first
  resize.is_a?(Array) ? { width: resize[0], height: resize[1] } : {}
end

#async_variant_direct_url(variant) ⇒ Object 



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# File 'lib/active_storage/async_variants/helper.rb', line 61

def async_variant_direct_url(variant)
  if cdn = ActiveStorage::AsyncVariants.cdn_host
    "#{cdn}/#{variant.key}"
  else
    variant.image.url
  end
end

#async_variant_frame_id(variant) ⇒ Object 



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# File 'lib/active_storage/async_variants/helper.rb', line 46

def async_variant_frame_id(variant)
  digest = variant.variation.digest.gsub(/[^a-zA-Z0-9_-]/, "")
  "async-variant-#{variant.blob.id}-#{digest}"
end

#async_variant_frame_src(variant, kind:, direct:, html_options: {}) ⇒ Object 



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# File 'lib/active_storage/async_variants/helper.rb', line 51

def async_variant_frame_src(variant, kind:, direct:, html_options: {})
  async_variant_state_path(
    signed_blob_id: variant.blob.signed_id,
    variation_key: variant.variation.key,
    kind:,
    direct:,
    opts: html_options.slice(*PASS_THROUGH_HTML_OPTIONS),
  )
end

#async_variant_placeholder_tag(variant, html_options = {}, kind: :image) ⇒ Object 



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# File 'lib/active_storage/async_variants/helper.rb', line 14

def async_variant_placeholder_tag(variant, html_options = {}, kind: :image)
  opts = async_variant_box_dimensions(variant)
    .merge(html_options.symbolize_keys.except(:src, :controls, :autoplay, :preload, :poster))
  # A video placeholder carries no <source>, so it reserves the box
  # without loading anything -- same zero-network intent as the GIF.
  kind == :video ? content_tag(:video, "", opts) : image_tag(PLACEHOLDER_SRC, opts)
end

#async_variant_processed_inline?(variant) ⇒ Boolean

In test with non-bucket-backed services, the gem defers to vanilla ActiveStorage (synchronous vips transform) – inline rendering keeps those environments simple. Otherwise, only inline a normal <img> when the variant has reached the processed terminal state.

Returns:

  • (Boolean) 


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# File 'lib/active_storage/async_variants/helper.rb', line 33

def async_variant_processed_inline?(variant)
  !variant.blob.bucket_backed? || variant.async_state == "processed"
end

#async_variant_representation_path(variant) ⇒ Object 



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# File 'lib/active_storage/async_variants/helper.rb', line 69

def async_variant_representation_path(variant)
  Rails.application.routes.url_helpers.rails_blob_representation_path(
    variant.blob.signed_id,
    variant.variation.key,
    variant.blob.filename.to_s,
  )
end

#async_variant_resolved_src(variant, direct:) ⇒ Object 



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# File 'lib/active_storage/async_variants/helper.rb', line 37

def async_variant_resolved_src(variant, direct:)
  if direct && variant.async_state == "processed"
    async_variant_direct_url(variant)
  else
    variant.processed if variant.blob.bucket_backed?
    async_variant_representation_path(variant)
  end
end