Class: Longleaf::ServiceCandidateIndexIterator

Inherits:
Object
  • Object
show all
Includes:
Logging
Defined in:
lib/longleaf/candidates/service_candidate_index_iterator.rb

Overview

Iterator for getting file candidates which have services which need to be run. Implementation uses an index of file metadata to determine if the file needs any services run.

Instance Method Summary collapse

Methods included from Logging

#initialize_logger, initialize_logger, logger, #logger

Constructor Details

#initialize(file_selector, event, app_config, force = false) ⇒ ServiceCandidateIndexIterator

Returns a new instance of ServiceCandidateIndexIterator.



13
14
15
16
17
18
19
20
21
 
# File 'lib/longleaf/candidates/service_candidate_index_iterator.rb', line 13

def initialize(file_selector, event, app_config, force = false)
  @file_selector = file_selector
  @event = event
  @app_config = app_config
  @force = force
  @index_manager = @app_config.index_manager
  @stale_datetime = Time.now.utc
  @result_set = nil
end

Instance Method Details

#each ⇒ Object

Iterate through the candidates in this object and execute the provided block with each candidate. A block is required.



60
61
62
63
64
65
66
67
 
# File 'lib/longleaf/candidates/service_candidate_index_iterator.rb', line 60

def each
  file_rec = next_candidate
  until file_rec.nil?
    yield file_rec

    file_rec = next_candidate
  end
end

#next_candidate ⇒ FileRecord

Get the file record for the next candidate which needs services run which match the provided file_selector

Returns:

  • (FileRecord) —

    file record of the next candidate with services needing to be run, or nil if there are no more candidates.



27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
 
# File 'lib/longleaf/candidates/service_candidate_index_iterator.rb', line 27

def next_candidate
  file_rec = nil
  # loop until a candidate with metadata is retrieved
  loop do
    # Get the next page of results if the previous page has been processed
    fetch_next_page if @result_set.nil? || @result_set.empty?

    # Retrieve the next possible candidate path from the page
    next_path = @result_set.shift
    # given that the page was just retrieved, getting a nil path indicates that the retrieved page of
    # candidates is empty and there are no more candidates to iterate at this time.
    return nil if next_path.nil?

    logger.debug("Retrieved candidate #{next_path}")
    storage_loc = @app_config.location_manager.get_location_by_path(next_path)
    file_rec = FileRecord.new(next_path, storage_loc)

    # Keep seeking until a registered candidate is found, according to the file system.
    if file_rec.metadata_present?
      break
    else
      logger.warn("Encountered #{next_path} in index, but path is not registered. Clearing out of synch entry.")
      @index_manager.remove(file_rec)
    end
  end

  @app_config.md_manager.load(file_rec)

  file_rec
end