When we introduced unicode support in the regular expressions used in watched words (9a27803) we didn't realize the cost adding the `u` flag would be.
Turns out, it's pretty bad when you have lots of regular expressions to test. A customer had slightly less than 200 watched words, and it would freeze the browser for about 2s on the first check of those regular expressions (roughly 10ms per regular expression).
This commit introduces a new field (`word`) to the serialized watched words which is then converted to a very fast and cheap regular expression on the client-side. We use that regexp to quicly check whether a matcher is even worth trying so that we don't incure the cost of compiling the expensive unicode regexp.
This commit also busts the `WordWatcher` cache since we added a new field to be serialized.
One nice side effect of using `matchAll` instead of a `while / exec` loop is that the likeliness of having a bad regexp matching infinitely is vastly reduced 🙌
Watched words were converted to regular expressions containing \W, which
handled only ASCII characters. Using [^[:word]] instead ensures that
UTF-8 characters are also handled correctly.
We currently apply type: :link watched words to custom user fields. This makes the user card pretty ugly because we don't allow html / links there. Additionally, the admin UI also does not say that we apply this to custom user fields, but only words in posts.
So this PR is to remove the replacement of link-type watch words for custom user fields.
862007fb18 introduced a change to the format that watched words are cached in Redis. Newly-deployed versions of the app were attempting to load the old-format data from Redis, leading to a server error. This commit introduces a CACHE_VERSION constant which we can easily bump when making changes to the cache schema.
* FEATURE: Add case-sensitivity flag to watched_words
Currently, all watched words are matched case-insensitively. This flag
allows a watched word to be flagged for case-sensitive matching.
To allow allow for backwards compatibility the flag is set to false by
default.
* FEATURE: Support case-sensitive creation of Watched Words via API
Extend admin creation and upload of Watched Words to support case
sensitive flag. This lays the ground work for supporting
case-insensitive matching of Watched Words.
Support for an extra column has also been introduced for the Watched
Words upload CSV file. The new column structure is as follows:
word,replacement,case_sentive
* FEATURE: Enable case-sensitive matching of Watched Words
WordWatcher's word_matcher_regexp now returns a list of regular
expressions instead of one case-insensitive regular expression.
With the ability to flag a Watched Word as case-sensitive, an action
can have words of both sensitivities.This makes the use of the global
Regexp::IGNORECASE flag added to all words problematic.
To get around platform limitations around the use of subexpression level
switches/flags, a list of regular expressions is returned instead, one for each
case sensitivity.
Word matching has also been updated to use this list of regular expressions
instead of one.
* FEATURE: Use case-sensitive regular expressions for Watched Words
Update Watched Words regular expressions matching and processing to handle
the extra metadata which comes along with the introduction of
case-sensitive Watched Words.
This allows case-sensitive Watched Words to matched as such.
* DEV: Simplify type casting of case-sensitive flag from uploads
Use builtin semantics instead of a custom method for converting
string case flags in uploaded Watched Words to boolean.
* UX: Add case-sensitivity details to Admin Watched Words UI
Update Watched Word form to include a toggle for case-sensitivity.
This also adds support for, case-sensitive testing and matching of Watched Word
in the admin UI.
* DEV: Code improvements from review feedback
- Extract watched word regex creation out to a utility function
- Make JS array presence check more explicit and readable
* DEV: Extract Watched Word regex creation to utility function
Clean-up work from review feedback. Reduce code duplication.
* DEV: Rename word_matcher_regexp to word_matcher_regexp_list
Since a list is returned now instead of a single regular expression,
change `word_matcher_regexp` to `word_matcher_regexp_list` to better communicate
this change.
* DEV: Incorporate WordWatcher updates from upstream
Resolve conflicts and ensure apply_to_text does not remove non-word characters in matches
that aren't at the beginning of the line.
The previous method for reused the PrettyText logic which applied the
watched word logic, but had the unwanted effect of cooking the text too.
This meant that regular text values were converted to HTML.
Follow up to commit 5a4c35f627.
Fixes a flaky spec:
```
1) WordWatcher.word_matcher_regexp format of the result regexp is correct when watched_words_regular_expressions = true
Failure/Error: expect(regexp.inspect).to eq("/(#{word1})|(#{word2})/i")
expected: "/(word35)|(word36)/i"
got: "/(word36)|(word35)/i"
(compared using ==)
# ./spec/services/word_watcher_spec.rb:19:in `block (4 levels) in <main>'
```
Censored watched words were not censored inside the title of an inline
oneboxes. Malicious users could exploit this behaviour to insert bad
words. The same issue has been fixed for regular Oneboxes in commit
d184fe59ca.
The cache was causing state to leak between tests since the `WatchedWord` record in the DB would have been rolled back but `WordWatcher` still had the word in the cache.
The generated regular expressions did not contain \b which matched
every text that contained the word, even if it was only a substring of
a word.
For example, if "art" was a watched word a post containing word
"artist" matched.
It was not clear that replace watched words can be used to replace text
with URLs. This introduces a new watched word type that makes it easier
to understand.
Watched words are always regular expressions, despite watched_words_
_regular_expressions being enabled or not. Internally, wildcard
characters are replaced with a regular expression that matches any non
whitespace character.
* FIX: Hide tag watched words if tagging is disabled
These 'autotag' words were shown even if tagging was disabled.
* FIX: Make autotag watched words case insensitive
This commit also fixes the bug when no tag was applied if no other tag
was already present.
Previously watched words ignored topic titles when applying auto tagging rules.
Also copy has been improved to reflect how the system behaves.
The text hints that we are only watching first post now
This commit includes other various improvements to watched words.
auto_silence_first_post_regex site setting was removed because it overlapped
with 'require approval' watched words.
- Client-side censoring fixed for non-chrome browsers. (Regular expression rewritten to avoid lookback)
- Regex generation is now done on the server, to reduce repeated logic, and make it easier to extend in plugins
- Censor tests are moved to ruby, to ensure everything works end-to-end
- If "watched words regular expressions" is enabled, warn the admin when the generated regex is invalid
This commit contains 3 features:
- FEATURE: Allow downloading watched words
This introduces a button that allows admins to download watched words per action in a `.txt` file.
- FEATURE: Allow clearing watched words in bulk
This adds a "Clear All" button that clears all deleted words per action (e.g. block, flag etc.)
- FEATURE: List all blocked words contained in the post when it's blocked
When a post is rejected because it contains one or more blocked words, the error message now lists all the blocked words contained in the post.
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This also changes the format of the file for importing watched words from `.csv` to `.txt` so it becomes inconsistent with the extension of the file when watched words are exported.
This reduces chances of errors where consumers of strings mutate inputs
and reduces memory usage of the app.
Test suite passes now, but there may be some stuff left, so we will run
a few sites on a branch prior to merging
