Class: Moab::FileGroupDifference

Inherits:
Serializable
  • Object
show all
Includes:
HappyMapper
Defined in:
lib/moab/file_group_difference.rb

Overview

Note:

Copyright © 2012 by The Board of Trustees of the Leland Stanford Junior University. All rights reserved. See LICENSE for details.

Performs analysis and reports the differences between two matching FileGroup objects. The descending elements of the report hold a detailed breakdown of file-level differences, organized by change type. This stanza is a child element of FileInventoryDifference, the documentation of which contains a full example.

In order to determine the detailed nature of the differences that are present between the two manifests, this algorithm first compares the sets of file signatures present in the groups being compared, then uses the result of that operation for subsequent analysis of filename correspondences.

For the first step, a Ruby Hash is extracted from each of the of the two groups, with an array of FileSignature object used as hash keys, and the corresponding FileInstance arrays as the hash values. The set of keys from the basis hash can be compared against the keys from the other hash using Array operators:

  • matching = basis_array & other_array

  • basis_only = basis_array - other_array

  • other_only = other_array - basis_array

For the second step of the comparison, the matching and non-matching sets of hash entries are further categorized as follows:

  • identical = signature and file path is the same in both basis and other file group

  • renamed = signature is unchanged, but the path has moved

  • copyadded = duplicate copy of file was added

  • copydeleted = duplicate copy of file was deleted

  • modified = path is same in both groups, but the signature has changed

  • added = signature and path are only in the other inventor

  • deleted = signature and path are only in the basis inventory

Data Model

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(opts = {}) ⇒ FileGroupDifference

Returns a new instance of FileGroupDifference


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# File 'lib/moab/file_group_difference.rb', line 56

def initialize(opts={})
  @subset_hash = Hash.new {|hash, key| hash[key] = FileGroupDifferenceSubset.new(:change => key.to_s)}
  super(opts)
end

Instance Attribute Details

#addedInteger

Returns How many files were added

Returns:

  • (Integer)

    How many files were added


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# File 'lib/moab/file_group_difference.rb', line 114

attribute :added, Integer, :on_save => Proc.new { |n| n.to_s }

#copyaddedInteger

Returns How many duplicate copies of files were added

Returns:

  • (Integer)

    How many duplicate copies of files were added


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# File 'lib/moab/file_group_difference.rb', line 86

attribute :copyadded, Integer, :on_save => Proc.new { |n| n.to_s }

#copydeletedInteger

Returns How many duplicate copies of files were deleted

Returns:

  • (Integer)

    How many duplicate copies of files were deleted


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# File 'lib/moab/file_group_difference.rb', line 93

attribute :copydeleted, Integer, :on_save => Proc.new { |n| n.to_s }

#deletedInteger

Returns How many files were deleted

Returns:

  • (Integer)

    How many files were deleted


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# File 'lib/moab/file_group_difference.rb', line 121

attribute :deleted, Integer, :on_save => Proc.new { |n| n.to_s }

#difference_countInteger

Returns the total number of differences found between the two inventories that were compared (dynamically calculated)

Returns:

  • (Integer)

    the total number of differences found between the two inventories that were compared (dynamically calculated)


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# File 'lib/moab/file_group_difference.rb', line 67

attribute :difference_count, Integer, :tag => 'differenceCount', :on_save => Proc.new { |i| i.to_s }

#group_idString

Returns The name of the file group

Returns:

  • (String)

    The name of the file group


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# File 'lib/moab/file_group_difference.rb', line 63

attribute :group_id, String, :tag => 'groupId', :key => true

#identicalInteger

Returns How many files were unchanged

Returns:

  • (Integer)

    How many files were unchanged


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# File 'lib/moab/file_group_difference.rb', line 79

attribute :identical, Integer, :on_save => Proc.new { |n| n.to_s }

#modifiedInteger

Returns How many files were modified

Returns:

  • (Integer)

    How many files were modified


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# File 'lib/moab/file_group_difference.rb', line 107

attribute :modified, Integer, :on_save => Proc.new { |n| n.to_s }

#renamedInteger

Returns How many files were renamed

Returns:

  • (Integer)

    How many files were renamed


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# File 'lib/moab/file_group_difference.rb', line 100

attribute :renamed, Integer, :on_save => Proc.new { |n| n.to_s }

#subset_hashHash<Symbol,FileGroupDifferenceSubset>

Returns A set of containers (one for each change type), each of which contains a collection of file-level differences having that change type.

Returns:

  • (Hash<Symbol,FileGroupDifferenceSubset>)

    A set of containers (one for each change type), each of which contains a collection of file-level differences having that change type.


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# File 'lib/moab/file_group_difference.rb', line 47

def subset_hash
  @subset_hash
end

#subsetsArray<FileGroupDifferenceSubset>

Returns A set of Arrays (one for each change type), each of which contains an collection of file-level differences having that change type.

Returns:

  • (Array<FileGroupDifferenceSubset>)

    A set of Arrays (one for each change type), each of which contains an collection of file-level differences having that change type.


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# File 'lib/moab/file_group_difference.rb', line 129

has_many :subsets, FileGroupDifferenceSubset, :tag => 'subset'

Instance Method Details

#basis_only_keys(basis_hash, other_hash) ⇒ Array

Returns Compare the keys of two hashes and return the keys unique to the first hash

Parameters:

  • basis_hash (Hash)

    The first hash being compared

  • other_hash (Hash)

    The second hash being compared

Returns:

  • (Array)

    Compare the keys of two hashes and return the keys unique to the first hash


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# File 'lib/moab/file_group_difference.rb', line 173

def basis_only_keys(basis_hash, other_hash)
  basis_hash.keys - other_hash.keys
end

#compare_file_groups(basis_group, other_group) ⇒ FileGroupDifference

Returns Compare two file groups and return a differences report

Parameters:

  • basis_group (FileGroup)

    The file group that is the basis of the comparison

  • other_group (FileGroup)

    The file group that is compared against the basis group

Returns:


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# File 'lib/moab/file_group_difference.rb', line 188

def compare_file_groups(basis_group, other_group)
  @group_id = basis_group.group_id
  compare_matching_signatures(basis_group, other_group)
  compare_non_matching_signatures(basis_group, other_group)
  self
end

#compare_matching_signatures(basis_group, other_group) ⇒ FileGroupDifference

Returns For signatures that are present in both groups, report which file instances are identical or renamed

Parameters:

  • basis_group (FileGroup)

    The file group that is the basis of the comparison

  • other_group (FileGroup)

    The file group that is compared against the basis group

Returns:

  • (FileGroupDifference)

    For signatures that are present in both groups, report which file instances are identical or renamed


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# File 'lib/moab/file_group_difference.rb', line 199

def compare_matching_signatures(basis_group, other_group)
  matching_signatures = matching_keys(basis_group.signature_hash, other_group.signature_hash)
  tabulate_unchanged_files(matching_signatures, basis_group.signature_hash, other_group.signature_hash)
  tabulate_renamed_files(matching_signatures, basis_group.signature_hash, other_group.signature_hash)
  self
end

#compare_non_matching_signatures(basis_group, other_group) ⇒ FileGroupDifference

Returns For signatures that are present in only one or the other group, report which file instances are modified, deleted, or added

Parameters:

  • basis_group (FileGroup)

    The file group that is the basis of the comparison

  • other_group (FileGroup)

    The file group that is compared against the basis group

Returns:

  • (FileGroupDifference)

    For signatures that are present in only one or the other group, report which file instances are modified, deleted, or added


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# File 'lib/moab/file_group_difference.rb', line 210

def compare_non_matching_signatures(basis_group, other_group)
  basis_only_signatures = basis_only_keys(basis_group.signature_hash, other_group.signature_hash)
  other_only_signatures = other_only_keys(basis_group.signature_hash, other_group.signature_hash)
  basis_path_hash = basis_group.path_hash_subset(basis_only_signatures)
  other_path_hash = other_group.path_hash_subset(other_only_signatures)
  tabulate_modified_files(basis_path_hash, other_path_hash)
  tabulate_added_files(basis_path_hash, other_path_hash)
  tabulate_deleted_files(basis_path_hash, other_path_hash)
  self
end

#file_deltasHash<Symbol,Array>

Returns Sets of filenames grouped by change type for use in performing file or metadata operations

Returns:

  • (Hash<Symbol,Array>)

    Sets of filenames grouped by change type for use in performing file or metadata operations


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# File 'lib/moab/file_group_difference.rb', line 338

def file_deltas()
  # The hash to be returned
  deltas = Hash.new {|hash, key| hash[key] = []}
  # case where other_path is empty or 'same'.  (create array of strings)
  [:identical, :modified, :deleted, :copydeleted].each do |change|
    deltas[change].concat @subset_hash[change].files.collect{|file| file.basis_path}
  end
  # case where basis_path and other_path are both present.  (create array of arrays)
  [:copyadded, :renamed].each do |change|
    deltas[change].concat @subset_hash[change].files.collect{|file| [file.basis_path,file.other_path]}
  end
  # case where basis_path is empty.  (create array of strings)
  [:added].each do |change|
    deltas[change].concat @subset_hash[change].files.collect{|file| file.other_path}
  end
  deltas
end

#matching_keys(basis_hash, other_hash) ⇒ Array

Returns Compare the keys of two hashes and return the intersection

Parameters:

  • basis_hash (Hash)

    The first hash being compared

  • other_hash (Hash)

    The second hash being compared

Returns:

  • (Array)

    Compare the keys of two hashes and return the intersection


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# File 'lib/moab/file_group_difference.rb', line 166

def matching_keys(basis_hash, other_hash)
  basis_hash.keys & other_hash.keys
end

#other_only_keys(basis_hash, other_hash) ⇒ Array

Returns Compare the keys of two hashes and return the keys unique to the second hash

Parameters:

  • basis_hash (Hash)

    The first hash being compared

  • other_hash (Hash)

    The second hash being compared

Returns:

  • (Array)

    Compare the keys of two hashes and return the keys unique to the second hash


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# File 'lib/moab/file_group_difference.rb', line 180

def other_only_keys(basis_hash, other_hash)
  other_hash.keys - basis_hash.keys
end

#rename_require_temp_files(filepairs) ⇒ Boolean

Returns Test whether any of the new names are the same as one of the old names, such as would be true for insertion of a new file into a page sequence, or a circular rename. In such a case, return true, indicating that use of intermediate temporary files would be required when updating a copy of an object's files at a given location.

Parameters:

  • filepairs (Array<Array<String>>)

    The set of oldname, newname pairs for all files being renamed

Returns:

  • (Boolean)

    Test whether any of the new names are the same as one of the old names, such as would be true for insertion of a new file into a page sequence, or a circular rename. In such a case, return true, indicating that use of intermediate temporary files would be required when updating a copy of an object's files at a given location.


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# File 'lib/moab/file_group_difference.rb', line 361

def rename_require_temp_files(filepairs)
  # Split the filepairs into two arrays
  oldnames = []
  newnames = []
  filepairs.each do |old,new|
    oldnames << old
    newnames << new
  end
  # Are any of the filenames the same in set of oldnames and set of newnames?
  intersection = oldnames & newnames
  intersection.count > 0
end

#rename_tempfile_triplets(filepairs) ⇒ Array<Array<String>>

Returns a set of file triples containing oldname, tempname, newname

Parameters:

  • filepairs (Array<Array<String>>)

    The set of oldname, newname pairs for all files being renamed

Returns:

  • (Array<Array<String>>)

    a set of file triples containing oldname, tempname, newname


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# File 'lib/moab/file_group_difference.rb', line 376

def rename_tempfile_triplets(filepairs)
  filepairs.collect{|old,new| [old, new, "#{new}-#{Time.now.strftime('%Y%m%d%H%H%S')}-tmp"]}
end

#subset(change) ⇒ FileGroupDifferenceSubset

Returns Find a specified subset of changes

Parameters:

  • change (String)

    the change type to search for

Returns:


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# File 'lib/moab/file_group_difference.rb', line 51

def subset(change)
  @subset_hash[change.to_sym]
end

#summaryFileGroupDifference

Returns Clone just this element for inclusion in a versionMetadata structure

Returns:

  • (FileGroupDifference)

    Clone just this element for inclusion in a versionMetadata structure


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# File 'lib/moab/file_group_difference.rb', line 149

def summary()
  FileGroupDifference.new(
      :group_id => group_id,
      :identical => identical,
      :copyadded => copyadded,
      :copydeleted => copydeleted,
      :renamed => renamed,
      :modified => modified,
      :added => added,
      :deleted => deleted
  )
end

#summary_fieldsArray<String>

Returns The data fields to include in summary reports

Returns:

  • (Array<String>)

    The data fields to include in summary reports


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# File 'lib/moab/file_group_difference.rb', line 142

def summary_fields
  %w{group_id difference_count identical copyadded copydeleted renamed modified deleted added}
end

#tabulate_added_files(basis_path_hash, other_path_hash) ⇒ FileGroupDifference

Returns Container for reporting the set of file-level differences of type 'added'

Parameters:

  • basis_path_hash (Hash<String,FileSignature>)

    The file paths and associated signatures for manifestations appearing only in the basis group

  • other_path_hash (Hash<String,FileSignature>)

    The file paths and associated signatures for manifestations appearing only in the other group

Returns:

  • (FileGroupDifference)

    Container for reporting the set of file-level differences of type 'added'


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# File 'lib/moab/file_group_difference.rb', line 308

def tabulate_added_files(basis_path_hash, other_path_hash)
  other_only_keys(basis_path_hash, other_path_hash).each do |path|
    fid = FileInstanceDifference.new(:change => 'added')
    fid.basis_path = ""
    fid.other_path = path
    fid.signatures << other_path_hash[path]
    @subset_hash[:added].files << fid
  end
  self
end

#tabulate_deleted_files(basis_path_hash, other_path_hash) ⇒ FileGroupDifference

Returns Container for reporting the set of file-level differences of type 'deleted'

Parameters:

  • basis_path_hash (Hash<String,FileSignature>)

    The file paths and associated signatures for manifestations appearing only in the basis group

  • other_path_hash (Hash<String,FileSignature>)

    The file paths and associated signatures for manifestations appearing only in the other group

Returns:

  • (FileGroupDifference)

    Container for reporting the set of file-level differences of type 'deleted'


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# File 'lib/moab/file_group_difference.rb', line 326

def tabulate_deleted_files(basis_path_hash, other_path_hash)
  basis_only_keys(basis_path_hash, other_path_hash).each do |path|
    fid = FileInstanceDifference.new(:change => 'deleted')
    fid.basis_path = path
    fid.other_path = ""
    fid.signatures << basis_path_hash[path]
    @subset_hash[:deleted].files << fid
  end
  self
end

#tabulate_modified_files(basis_path_hash, other_path_hash) ⇒ FileGroupDifference

Returns Container for reporting the set of file-level differences of type 'modified'

Parameters:

  • basis_path_hash (Hash<String,FileSignature>)

    The file paths and associated signatures for manifestations appearing only in the basis group

  • other_path_hash (Hash<String,FileSignature>)

    The file paths and associated signatures for manifestations appearing only in the other group

Returns:

  • (FileGroupDifference)

    Container for reporting the set of file-level differences of type 'modified'


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# File 'lib/moab/file_group_difference.rb', line 289

def tabulate_modified_files(basis_path_hash, other_path_hash)
  matching_keys(basis_path_hash, other_path_hash).each do |path|
    fid = FileInstanceDifference.new(:change => 'modified')
    fid.basis_path = path
    fid.other_path = "same"
    fid.signatures << basis_path_hash[path]
    fid.signatures << other_path_hash[path]
    @subset_hash[:modified].files << fid
  end
  self
end

#tabulate_renamed_files(matching_signatures, basis_signature_hash, other_signature_hash) ⇒ FileGroupDifference

Returns Container for reporting the set of file-level differences of type 'renamed','copyadded', or 'copydeleted'

Parameters:

  • matching_signatures (Array<FileSignature>)

    The file signature of the file manifestations being compared

  • basis_signature_hash (Hash<FileSignature, FileManifestation>)

    Signature to file path mapping from the file group that is the basis of the comparison

  • other_signature_hash (Hash<FileSignature, FileManifestation>)

    Signature to file path mapping from the file group that is the being compared to the basis group

Returns:

  • (FileGroupDifference)

    Container for reporting the set of file-level differences of type 'renamed','copyadded', or 'copydeleted'


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# File 'lib/moab/file_group_difference.rb', line 254

def tabulate_renamed_files(matching_signatures, basis_signature_hash, other_signature_hash)
  matching_signatures.each do |signature|
    basis_paths = basis_signature_hash[signature].paths
    other_paths = other_signature_hash[signature].paths
    basis_only_paths = basis_paths - other_paths
    other_only_paths = other_paths - basis_paths
    maxsize = [basis_only_paths.size, other_only_paths.size].max
    (0..maxsize-1).each do |n|
      fid = FileInstanceDifference.new()
      fid.basis_path = basis_only_paths[n]
      fid.other_path = other_only_paths[n]
      fid.signatures << signature
      case true
        when fid.basis_path.nil?
          fid.change = 'copyadded'
          fid.basis_path = basis_paths[0]
        when fid.other_path.nil?
          fid.change = 'copydeleted'
        else
          fid.change = 'renamed'
      end
      @subset_hash[fid.change.to_sym].files << fid
    end
  end
  self
end

#tabulate_unchanged_files(matching_signatures, basis_signature_hash, other_signature_hash) ⇒ FileGroupDifference

Returns Container for reporting the set of file-level differences of type 'identical'

Parameters:

  • matching_signatures (Array<FileSignature>)

    The file signature of the file manifestations being compared

  • basis_signature_hash (Hash<FileSignature, FileManifestation>)

    Signature to file path mapping from the file group that is the basis of the comparison

  • other_signature_hash (Hash<FileSignature, FileManifestation>)

    Signature to file path mapping from the file group that is the being compared to the basis group

Returns:

  • (FileGroupDifference)

    Container for reporting the set of file-level differences of type 'identical'


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# File 'lib/moab/file_group_difference.rb', line 229

def tabulate_unchanged_files(matching_signatures, basis_signature_hash, other_signature_hash)
  matching_signatures.each do |signature|
    basis_paths = basis_signature_hash[signature].paths
    other_paths = other_signature_hash[signature].paths
    matching_paths = basis_paths & other_paths
    matching_paths.each do |path|
      fid = FileInstanceDifference.new(:change => 'identical')
      fid.basis_path = path
      fid.other_path = "same"
      fid.signatures << signature
      @subset_hash[:identical].files << fid
    end
  end
  self
end