Read data from a file in CodeQl Query

[Shivam60]

We have a JavaScript database which we want to scan through for a list of literals (URLS)

The list of literals that we want to scan against is 1000 long and we are trying to find the possible way to do so.
One solution that comes to mind is to store all the 1000 literals in a JSON file, read the JSON file in query and use it for comparison?

Is it possible to read a JSON/file in a CodeQl query ?
Is there any other approach that can be suggested for this use case?

[aibaars]

@Shivam60 The feature you are asking for is not currently available, but it is something that the team is working on. In the mean time there are a couple of solutions:

Is this a static list of URLs? If so, you could include the contents in the query or a QLL library file. For example:

string getAUrl() {
  result = [ "https://bing.com", "https://google.com", ... ]
}

Defining a 1000 literals like that should be fine. See for example the "typo database" used by some queries: https://github.com/github/codeql/blob/b609f1ea52ccd866dde87d093fe67648471ef6f6/ql/ql/src/codeql_ql/style/TypoDatabase.qll

If the list is different each time you run the query, then you could consider using an external predicate and supply a CSV file with the URLs for that predicate when running the query.

external string getAUrl();

> codeql query run --help
Usage: codeql query run [OPTIONS] -- <file.ql>
Run a single query.
...
      --external=<pred>=<file.csv>
                             A CSV file that contains rows for external
                               predicate <pred>. Multiple --external options
                               can be supplied.
...

[AryazE]

@aibaars I didn't find documentation for external predicates. Can the CSV file contain multiple columns to specify a more complicated type or each line should be a single literal of primitive types?