problem with cached rules after changing a rule

[tq-krutzc]

Description

If I add/update/delete a rule, scancode is somehow caching the old ones. I tried deleting ~/.cache/scancode-tk and drop the cache (/proc/sys/vm/drop_cache), unsuccessfully.
How can the cached data be updated or be ignored?

How To Reproduce

• run a scan
• add/update/delete a rule
• run the same scan, again
• scancode does not know the changes in the rules

System configuration

• What OS are you running on? (Windows/MacOS/Linux)
  Ubuntu 18.04
• What version of scancode-toolkit was used to generate the scan file?
  3.1.1
• What installation method was used to install/run scancode? (pip/source download/other)
  download

[pombredanne]

The short story:

Use this

• add/update/delete a rule
• run scancode --reindex-licenses
• run the same scan, again

The long story:

There are two modes that drive license cache handling: the regular "user" mode and the "development" mode.

• In "development" mode, (typically from a git checkout), you typically start by calling first ./configure. This will create an empty tag file at the root of your scancode checkout named SCANCODE_DEV_MODE. When this file is present, any change to the code or to the license data (e.g. rules or licenses) will trigger a cache deletion and reindexing. In that mode the cache is stored at the root of your scancode checkout in a .cache directory

• Otherwise if that file is not present (e.g. when running from an archive and when you start with a call to ./scancode rather than ./configure), the cache is created once and never checked afterwards. The cache is created and used in ~/.cache/scancode-tk as you found out..

FWIW, the code that handles this is there https://github.com/nexB/scancode-toolkit/blob/9202df472aaec9dd6657e8babe8e79519140519f/src/licensedcode/cache.py#L184

In any case and in any mode, you can force a cache check and a reindexing by running scancode --reindex-licenses. If needed the cache will be recreated in the location used for your "mode"

(though it happens automatically when you have a SCANCODE_DEV_MODE tag file present)

Note also that there is this ticket #480 that has long been in the waiting.

[tq-krutzc]

Thanks, again :-)