discourse/spec/lib/db_helper_spec.rb
Selase Krakani 9b0cfa99c5
DEV: Gracefully handle remaps which violate DB column constraints (#29501)
* DEV: Gracefully handle remaps which violate DB column constraints

This change implements length constraint enforcement to skip remaps
which exceed column max lengths

* DEV: Only perform skipped column stats lookup when verbose is true

* DEV: Tidy up specs

* DEV: Make skipping violating remap behaviour opt-in

This change introduces a new `skip_max_length_violations` param for
`remap`, set to `false` by default to ensure we still continue to fail
hard when max lenth constraints are violated.

To aid in quick resolution when remaps fail, this change also
adds more context to the exception message to include the offending table
and column information

* Apply suggestions from code review

Co-authored-by: Gerhard Schlager <gerhard.schlager@discourse.org>

* FIX: Various fixes

- Linter errors
- Remap status "logger" early return condition

---------

Co-authored-by: Gerhard Schlager <gerhard.schlager@discourse.org>
2024-11-15 10:42:25 +00:00

102 lines
3.1 KiB
Ruby

# frozen_string_literal: true
RSpec.describe DbHelper do
describe ".remap" do
fab!(:bookmark1) { Fabricate(:bookmark, name: "short-bookmark") }
fab!(:bookmark2) { Fabricate(:bookmark, name: "another-bookmark") }
let(:bookmark_name_limit) { Bookmark.columns_hash["name"].limit }
let(:long_bookmark_name) { "a" * (bookmark_name_limit + 1) }
it "should remap columns properly" do
post = Fabricate(:post, cooked: "this is a specialcode that I included")
post_attributes = post.reload.attributes
badge = Fabricate(:badge, query: "specialcode")
badge_attributes = badge.reload.attributes
DbHelper.remap("specialcode", "codespecial")
post.reload
expect(post.cooked).to include("codespecial")
badge.reload
expect(badge.query).to eq("codespecial")
expect(badge_attributes.except("query")).to eq(badge.attributes.except("query"))
end
it "allows tables to be excluded from scanning" do
post = Fabricate(:post, cooked: "test")
DbHelper.remap("test", "something else", excluded_tables: %w[posts])
expect(post.reload.cooked).to eq("test")
end
it "does not remap readonly columns" do
post = Fabricate(:post, raw: "This is a test", cooked: "This is a test")
Migration::ColumnDropper.mark_readonly("posts", "cooked")
DbHelper.remap("test", "something else")
post.reload
expect(post.raw).to eq("This is a something else")
expect(post.cooked).to eq("This is a test")
DB.exec "DROP FUNCTION #{Migration::BaseDropper.readonly_function_name("posts", "cooked")} CASCADE"
end
context "when skip_max_length_violations is false" do
it "raises an exception if remap exceeds column length constraint by default" do
expect { DbHelper.remap("bookmark", long_bookmark_name) }.to raise_error(
PG::StringDataRightTruncation,
/value too long.*table: bookmarks,.*name/,
)
end
end
context "when skip_max_length_violations is true" do
it "skips a remap eligible row if new value exceeds column length constraint" do
DbHelper.remap("bookmark", long_bookmark_name, skip_max_length_violations: true)
bookmark1.reload
bookmark2.reload
expect(bookmark1.name).to eq("short-bookmark")
expect(bookmark2.name).to eq("another-bookmark")
end
it "logs skipped remaps due to max length constraints when verbose is true" do
expect {
DbHelper.remap(
"bookmark",
long_bookmark_name,
verbose: true,
skip_max_length_violations: true,
)
}.to output(/SKIPPED:/).to_stdout
bookmark1.reload
bookmark2.reload
expect(bookmark1.name).to eq("short-bookmark")
expect(bookmark2.name).to eq("another-bookmark")
end
end
end
describe ".regexp_replace" do
it "should remap columns correctly" do
post = Fabricate(:post, raw: "this is a [img]test[/img] post")
DbHelper.regexp_replace("\\[img\\]test\\[/img\\]", "[img]something[/img]")
expect(post.reload.raw).to include("[img]something[/img]")
end
end
end