discourse/app/models/draft.rb

298 lines
8.1 KiB
Ruby

# frozen_string_literal: true
class Draft < ActiveRecord::Base
NEW_TOPIC ||= 'new_topic'
NEW_PRIVATE_MESSAGE ||= 'new_private_message'
EXISTING_TOPIC ||= 'topic_'
class OutOfSequence < StandardError; end
def self.set(user, key, sequence, data, owner = nil, retry_not_unique: true)
if SiteSetting.backup_drafts_to_pm_length > 0 && SiteSetting.backup_drafts_to_pm_length < data.length
backup_draft(user, key, sequence, data)
end
# this is called a lot so we should micro optimize here
draft_id, current_owner, current_sequence = DB.query_single(<<~SQL, user_id: user.id, key: key)
WITH draft AS (
SELECT id, owner FROM drafts
WHERE
user_id = :user_id AND
draft_key = :key
),
draft_sequence AS (
SELECT sequence
FROM draft_sequences
WHERE
user_id = :user_id AND
draft_key = :key
)
SELECT
(SELECT id FROM draft),
(SELECT owner FROM draft),
(SELECT sequence FROM draft_sequence)
SQL
current_sequence ||= 0
if draft_id
if current_sequence != sequence
raise Draft::OutOfSequence
end
if owner && current_owner && current_owner != owner
sequence += 1
DraftSequence.upsert({
sequence: sequence,
draft_key: key,
user_id: user.id,
},
unique_by: [:user_id, :draft_key]
)
end
DB.exec(<<~SQL, id: draft_id, sequence: sequence, data: data, owner: owner || current_owner)
UPDATE drafts
SET sequence = :sequence
, data = :data
, revisions = revisions + 1
, owner = :owner
WHERE id = :id
SQL
elsif sequence != current_sequence
raise Draft::OutOfSequence
else
begin
Draft.create!(
user_id: user.id,
draft_key: key,
data: data,
sequence: sequence,
owner: owner
)
rescue ActiveRecord::RecordNotUnique => e
# we need this to be fast and with minimal locking, in some cases we can have a race condition
# around 2 controller actions calling for draft creation at the exact same time
# to avoid complex locking and a distributed mutex, since this is so rare, simply add a single retry
if retry_not_unique
set(user, key, sequence, data, owenr, retry_not_unique: false)
else
raise e
end
end
end
sequence
end
def self.get(user, key, sequence)
opts = {
user_id: user.id,
draft_key: key,
sequence: sequence
}
current_sequence, data, draft_sequence = DB.query_single(<<~SQL, opts)
WITH draft AS (
SELECT data, sequence
FROM drafts
WHERE draft_key = :draft_key AND user_id = :user_id
),
draft_sequence AS (
SELECT sequence
FROM draft_sequences
WHERE draft_key = :draft_key AND user_id = :user_id
)
SELECT
( SELECT sequence FROM draft_sequence) ,
( SELECT data FROM draft ),
( SELECT sequence FROM draft )
SQL
current_sequence ||= 0
if sequence != current_sequence
raise Draft::OutOfSequence
end
data if current_sequence == draft_sequence
end
def self.clear(user, key, sequence)
current_sequence = DraftSequence.current(user, key)
# bad caller is a reason to complain
if sequence != current_sequence
raise Draft::OutOfSequence
end
# corrupt data is not a reason not to leave data
Draft.where(user_id: user.id, draft_key: key).destroy_all
end
def self.stream(opts = nil)
opts ||= {}
user_id = opts[:user].id
offset = (opts[:offset] || 0).to_i
limit = (opts[:limit] || 30).to_i
# JOIN of topics table based on manipulating draft_key seems imperfect
builder = DB.build <<~SQL
SELECT
d.*, t.title, t.id topic_id, t.archetype,
t.category_id, t.closed topic_closed, t.archived topic_archived,
pu.username, pu.name, pu.id user_id, pu.uploaded_avatar_id, pu.username_lower,
du.username draft_username, NULL as raw, NULL as cooked, NULL as post_number
FROM drafts d
LEFT JOIN LATERAL json_extract_path_text (d.data::json, 'postId') postId ON TRUE
LEFT JOIN posts p ON postId :: BIGINT = p.id
LEFT JOIN topics t ON
CASE
WHEN d.draft_key LIKE '%' || '#{EXISTING_TOPIC}' || '%'
THEN CAST(replace(d.draft_key, '#{EXISTING_TOPIC}', '') AS INT)
ELSE 0
END = t.id
JOIN users pu on pu.id = COALESCE(p.user_id, t.user_id, d.user_id)
JOIN users du on du.id = #{user_id}
/*where*/
/*order_by*/
/*offset*/
/*limit*/
SQL
builder
.where('d.user_id = :user_id', user_id: user_id.to_i)
.order_by('d.updated_at desc')
.offset(offset)
.limit(limit)
.query
end
def self.cleanup!
DB.exec(<<~SQL)
DELETE FROM drafts
WHERE sequence < (
SELECT MAX(s.sequence)
FROM draft_sequences s
WHERE s.draft_key = drafts.draft_key
AND s.user_id = drafts.user_id
)
SQL
# remove old drafts
delete_drafts_older_than_n_days = SiteSetting.delete_drafts_older_than_n_days.days.ago
Draft.where("updated_at < ?", delete_drafts_older_than_n_days).destroy_all
end
def self.backup_draft(user, key, sequence, data)
reply = JSON.parse(data)["reply"] || ""
return if reply.length < SiteSetting.backup_drafts_to_pm_length
post_id = BackupDraftPost.where(user_id: user.id, key: key).pluck_first(:post_id)
post = Post.where(id: post_id).first if post_id
if post_id && !post
BackupDraftPost.where(user_id: user.id, key: key).delete_all
end
indented_reply = reply.split("\n").map! do |l|
" #{l}"
end
draft_body = <<~MD
#{indented_reply.join("\n")}
```text
seq: #{sequence}
key: #{key}
```
MD
return if post && post.raw == draft_body
if !post
topic = ensure_draft_topic!(user)
Post.transaction do
post = PostCreator.new(
user,
raw: draft_body,
skip_jobs: true,
skip_validations: true,
topic_id: topic.id,
).create
BackupDraftPost.create!(user_id: user.id, key: key, post_id: post.id)
end
elsif post.last_version_at > 5.minutes.ago
# bypass all validations here to maximize speed
post.update_columns(
raw: draft_body,
cooked: PrettyText.cook(draft_body),
updated_at: Time.zone.now
)
else
revisor = PostRevisor.new(post, post.topic)
revisor.revise!(user, { raw: draft_body },
bypass_bump: true,
skip_validations: true,
skip_staff_log: true,
bypass_rate_limiter: true
)
end
rescue => e
Discourse.warn_exception(e, message: "Failed to backup draft")
end
def self.ensure_draft_topic!(user)
topic_id = BackupDraftTopic.where(user_id: user.id).pluck_first(:topic_id)
topic = Topic.find_by(id: topic_id) if topic_id
if topic_id && !topic
BackupDraftTopic.where(user_id: user.id).delete_all
end
if !topic
Topic.transaction do
creator = PostCreator.new(
user,
title: I18n.t("draft_backup.pm_title"),
archetype: Archetype.private_message,
raw: I18n.t("draft_backup.pm_body"),
skip_jobs: true,
skip_validations: true,
target_usernames: user.username
)
topic = creator.create.topic
BackupDraftTopic.create!(topic_id: topic.id, user_id: user.id)
end
end
topic
end
end
# == Schema Information
#
# Table name: drafts
#
# id :integer not null, primary key
# user_id :integer not null
# draft_key :string not null
# data :text not null
# created_at :datetime not null
# updated_at :datetime not null
# sequence :integer default(0), not null
# revisions :integer default(1), not null
# owner :string
#
# Indexes
#
# index_drafts_on_user_id_and_draft_key (user_id,draft_key) UNIQUE
#