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OpenHAB JRuby Script Library

watch

watch provides the ability to create a trigger on file and directory changes

argumentDescription
 Path to watch for changes, can be a directory or a file
glob:Limit events to paths matching this glob. Globs are matched using File.fnmatch? rules
for:Array of symbols to limit events to only specific change types, valid values are :created, :deleted, :modified

If a file or a path that does not exist is supplied as the argument to watch, the parent directory will be watched and the file or non-existent part of the supplied path will become the glob. For example, if the directory given is /tmp/foo/bar and /tmp/foo exists but bar does not exist inside of of /tmp/foo then the directory /tmp/foo will be watched for any files that match */bar.

If the last part of the path contains any glob characters e.g. /tmp/foo/*bar, the parent directory will be watched and the last part of the path will be treated as if it was passed as the glob: argument.

In other words, watch '/tmp/foo/*bar' is equivalent to watch '/tmp/foo', glob: '*bar'

Event

When an event is triggered to a rule, the event object has the following fields | field | Description | | ———- | ————————————————————————————————————————– | | path | Ruby Pathname object of the path that had an event | | type | Type of changes as a symbol, valid values are :created, :deleted, or :modified | | attachment | Attachment if supplied |

Examples

Watch items directory inside of the openhab configuration path and log any changes. OpenHAB.conf_root is available and is the path to the OpenHAB configuration directory as a Ruby pathname object.

rule 'watch directory' do
  watch OpenHAB.conf_root/'items'
  run { |event| logger.info("#{event.path.basename} - #{event.type}") }
end

Watch items directory for files that end in *.erb inside of the openhab configuration path and log any changes

rule 'watch directory' do
  watch OpenHAB.conf_root/'items', glob: '*.erb'
  run { |event| logger.info("#{event.path.basename} - #{event.type}") }
end

Watch items/foo.items inside of the openhab configuration path and log any changes

rule 'watch directory' do
  watch OpenHAB.conf_root/'items/foo.items'
  run { |event| logger.info("#{event.path.basename} - #{event.type}") }
end

Watch items/*.items inside of the openhab configuration path and log any changes

rule 'watch directory' do
  watch OpenHAB.conf_root/'items/*.items'
  run { |event| logger.info("#{event.path.basename} - #{event.type}") }
end

Watch items/*.items inside of the openhab configuration path for when items files are deleted or created (ignore changes)

rule 'watch directory' do
  watch OpenHAB.conf_root/'items/*.items', for: [:deleted, :created]
  run { |event| logger.info("#{event.path.basename} - #{event.type}") }
end