Create swf_assets:manifests:load task to save all manifest files

Doing that sweet, sweet backfill!! It's not exactly *fast*, since
there's about 570k records to work through, but it's pretty good all
things considered! Thanks, surprisingly-reusable async code!
This commit is contained in:
Emi Matchu 2024-02-23 14:06:49 -08:00
parent 9a3b33ea2f
commit 992954ce89
2 changed files with 98 additions and 60 deletions

View file

@ -117,10 +117,12 @@ class SwfAsset < ApplicationRecord
end
def manifest
raise "manifest_url is blank" if manifest_url.blank?
NeopetsMediaArchive.load_json(manifest_url)
end
def preload_manifest
raise "manifest_url is blank" if manifest_url.blank?
NeopetsMediaArchive.preload_file(manifest_url)
end
@ -251,7 +253,14 @@ class SwfAsset < ApplicationRecord
# NeopetsMediaArchive will share a pool of persistent connections for
# them.
swf_assets.map do |swf_asset|
semaphore.async { swf_asset.preload_manifest }
semaphore.async do
begin
swf_asset.preload_manifest
rescue StandardError => error
Rails.logger.error "Could not preload manifest for asset " +
"#{swf_asset.id} (#{swf_asset.manifest_url}): #{error.message}"
end
end
end
# Wait until all tasks are done.

View file

@ -35,75 +35,104 @@ namespace :swf_assets do
end
end
desc "Backfill manifest_url for SwfAsset models"
task manifests: [:environment] do
timeout = ENV.fetch("TIMEOUT", "5").to_i
namespace :manifests do
desc "Save all known manifests to the Neopets Media Archive"
task load: [:environment] do
# Log errors to STDOUT, but we don't need the info messages about
# successful saves.
Rails.logger = Logger.new(STDOUT, level: :error)
assets = SwfAsset.where(manifest_url: nil)
count = assets.count
puts "Found #{count} assets without manifests"
# Find all the manifests with known URLs. (We don't have a database
# filter for "do we already have the manifest downloaded", but that's
# okay, the preload method will quickly check that for us!)
swf_assets = SwfAsset.where.not(manifest_url: nil)
total_count = swf_assets.count
puts "Found #{total_count} assets with manifests"
Async do
# Share a pool of persistent connections, rather than reconnecting on
# each request. (This library does that automatically!)
internet = Async::HTTP::Internet.instance
# Load the assets in batches, then process each batch in two steps: first
# inferring all manifest URLs in the batch, then saving all assets in the
# batch. (This makes the update step more efficient, and it also avoids
# simultaneous queries across the fibers, which ActiveRecord disallows!)
#
# We keep track of a shared index `i` here, but we only actually
# increment it once each task is *done*, so that the numbers output in
# the right order!
i = 0
assets.find_in_batches(batch_size: 1000) do |batch|
# Create a barrier, to let us wait on all the tasks; then under it
# create a semaphore, to limit how many tasks run at once.
barrier = Async::Barrier.new
semaphore = Async::Semaphore.new(100, parent: barrier)
batch.each do |asset|
semaphore.async do |task|
manifest_url = nil
begin
task.with_timeout(timeout) do
manifest_url = infer_manifest_url(asset.url, internet)
end
rescue StandardError => error
i += 1
puts "[#{i}/#{count}] ⚠️ Skipping #{asset.id}: #{error.message}"
next
end
i += 1
puts "[#{i}/#{count}] Manifest for #{asset.id}: #{manifest_url}"
# Write, but don't yet save, the manifest URL.
asset.manifest_url = manifest_url
end
# For each batch of 1000 assets, load their manifests concurrently.
# Wrap everything in a top-level sync, so keyboard interrupts will
# propagate all the way up to here, instead of just cancelling the
# current batch.
Sync do
saved_count = 0
swf_assets.find_in_batches(batch_size: 1000) do |swf_assets|
SwfAsset.preload_manifests(swf_assets)
saved_count += swf_assets.size
puts "Loaded #{saved_count} of #{total_count} manifests"
end
end
end
# Wait for all the above tasks to finish. (Then, all of the assets that
# succeeded should have an unsaved `manifest_url` change.)
barrier.wait
desc "Backfill manifest_url for SwfAsset models"
task urls: [:environment] do
timeout = ENV.fetch("TIMEOUT", "5").to_i
# Save all of the assets in the batch. (We do this in a transaction not
# for the transactional semantics, but because it's notably faster than
# doing a commit between each query, which is what sending the queries
# individually would effectively do!)
begin
SwfAsset.transaction do
batch.each do |asset|
assets = SwfAsset.where(manifest_url: nil)
count = assets.count
puts "Found #{count} assets without manifests"
Sync do
# Share a pool of persistent connections, rather than reconnecting on
# each request. (This library does that automatically!)
internet = Async::HTTP::Internet.instance
# Load the assets in batches, then process each batch in two steps: first
# inferring all manifest URLs in the batch, then saving all assets in the
# batch. (This makes the update step more efficient, and it also avoids
# simultaneous queries across the fibers, which ActiveRecord disallows!)
#
# We keep track of a shared index `i` here, but we only actually
# increment it once each task is *done*, so that the numbers output in
# the right order!
i = 0
assets.find_in_batches(batch_size: 1000) do |batch|
# Create a barrier, to let us wait on all the tasks; then under it
# create a semaphore, to limit how many tasks run at once.
barrier = Async::Barrier.new
semaphore = Async::Semaphore.new(100, parent: barrier)
batch.each do |asset|
semaphore.async do |task|
manifest_url = nil
begin
asset.save!
task.with_timeout(timeout) do
manifest_url = infer_manifest_url(asset.url, internet)
end
rescue StandardError => error
puts "⚠️ Saving asset #{asset.id} failed: #{error.full_message}"
i += 1
puts "[#{i}/#{count}] ⚠️ Skipping #{asset.id}: #{error.message}"
next
end
i += 1
puts "[#{i}/#{count}] Manifest for #{asset.id}: #{manifest_url}"
# Write, but don't yet save, the manifest URL.
asset.manifest_url = manifest_url
end
end
rescue StandardError => error
puts "⚠️ Saving this batch failed: #{error.full_message}"
# Wait for all the above tasks to finish. (Then, all of the assets that
# succeeded should have an unsaved `manifest_url` change.)
barrier.wait
# Save all of the assets in the batch. (We do this in a transaction not
# for the transactional semantics, but because it's notably faster than
# doing a commit between each query, which is what sending the queries
# individually would effectively do!)
begin
SwfAsset.transaction do
batch.each do |asset|
begin
asset.save!
rescue StandardError => error
puts "⚠️ Saving asset #{asset.id} failed: #{error.full_message}"
end
end
end
rescue StandardError => error
puts "⚠️ Saving this batch failed: #{error.full_message}"
end
end
end
end