Pymarc utils

A set of functions to handle data using Python pymarc library :

• marc_utils_4.py using version 4.2.2 of the library
• marc_utils_5.py using version 5.2.0

Incompatible changes from marc_utils_4.py to marc_utils_5.py

• __sort_subfields() parameter curr_subf was renammed to subf_list
• force_indicators :
  • Parameter indicators (list of strings, defaulted to [" ", " "]) was changed to become two parameter ind1 & ind2, both str defaulted to None
  • Now, if their value is set to None (default behaviour), keeps their current value (before, default behaviour was to write to a blank and this function could not be used to keep the current field indicators)
• edit_specific_repeatable_subfield_content_with_regexp() returns a list of pymarc.field.Subfield instead of a list of string following old subfield managing system (code 1, value 1, code 2, value 2, etc.)
• Added edit_repeatable_subf_content_with_regexp_for_tag() which is the same as edit_specific_repeatable_subfield_content_with_regexp() except it takes as argument a record and a tag and edit all fields with that tag, like all functions except the two using regular expressions
• replace_specific_repeatable_subfield_content_not_matching_regexp() returns a list of pymarc.field.Subfield instead of a list of string following old subfield managing system (code 1, value 1, code 2, value 2, etc.)
• Added replace_repeatable_subf_content_not_matching_regexp_for_tag() which is the same as replace_specific_repeatable_subfield_content_not_matching_regexp() except it takes as argument a record and a tag and edit all fields with that tag, like all functions except the two using regular expressions
• Added field_as_string() and record_as_string() which returns the field / record as a string in WinIBW style
• Added all functions to retrieve dates from the record (get_years_in_specific_subfield(), get_year_from_UNM_100(), get_years_less_accurate() & get_years())
• Added merge_all_subfields_with_code() to merge all subfields witht the same code for each field with given tag

See pymarc releases in the GitLab repository for important changes in the library.

Functions

Getting data from fields

Function get_years_in_specific_subfield()

Returns a list of ints containing the first 4 consecutive numbers in the specified field-subfield couple.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag
• code (str) : the subfields code tag

Function get_year_from_UNM_100()

Returns a list of ints containing the position 9-12 or 0-3 of the 100$a if they are 4 consecutive numbers.

Takes as argument :

• record (pymarc.record.Record)
• [Optionnal] creation (bool, defaulted to False) : return the creation date (pos. 0-3) instead of the publication one (pos. 9-12)

Function get_years_less_accurate()

Returns a list of ints containing the first 4 consecutive numbers in the specified field (all subfields are analyzed). Note : dates inferior to 1700 or superioir to 2100 are deleted before returning the list.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag

Function get_years()

Returns a list of ints containing either :

• The first 4 consecutive numbers in the specified field-subfield (calls get_years_in_specific_subfield())
• The first 4 consecutive numbers in the specified field (calls get_years_less_accurate()).

Takes as argument :

• record (pymarc.record.Record)
• tags (list of tuple of 2 str) : a list of field + subfield or field + None

Example :

marc_utils.get_years(record, [
            ("214", "d"),
            ("330", None),
            ("615", "a"),
            ("200", None),
            ])
# Will call get_years_in_specific_subfield() for 214$d
# Then get_years_less_accurate() for 330
# Then get_years_in_specific_subfield() for 615$a
# Then get_years_less_accurate() for 200

Sorting fields or subfields

sort argument logic

Every functions that uses sort on subfields follow this logic :

• If a subfield code is not in the sort argument, its position will stay the same relative to the other subfields not moving
• If a subfield is in the sort argument, it will be moved to that order
• To sort at the end, use * as a code to separate codes used to sort at the beginning from codes used to sort at the end

For example :

• ["a", "b"] will put at the beginning all subfields using code a, followed by all subfields using code b, followed by all other subfields, keeping their original order
• ["*", "y", "z"] will keep every subfield in their original order except those with codes y & z, followed by all subfields with code y, followed at the end by all subfields with code z
• ["a", "*", "z"] will put at the beginning all subfields using code a, followed by all other subfields except those with codes z, followed at the end by all subfields with code z

Function sort_fields_by_tag()

Sorts the record fields by their tag.

Takes as argument : record (pymarc.record.Record)

Function sort_subfields_for_tag()

Sorts subfields for all fields with given tag.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to sort
• sort (list of str) : list of subfields codes to sort. See sort argument logic to see how to configure it for this indicator.

Forcing data

Function force_indicators()

Forces the indicators on every field with given tag. If an indicator is set to None, the field will keep it's current value.

The function does not check if given values are legal values.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to edit
• ind1 (str, default to None) : first indicator value
• ind2 (str, default to None) : second indicator value

Adding data

Function add_missing_subfield_to_field()

Adds a new subfield with given code & value to every field with given tag if they do not already have a subfield with that code.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to edit
• code (str) : the subfield code
• val (str) : the subfield value to add
• [Optionnal] pos (int, defaulted to 999) : the position of the new subfield (if added). First position is 0

Function edit_repeatable_subf_content_with_regexp_for_tag()

Applies a substitution using regular expression to all subfields with given codes for all fields with given tag. No flag are used and no flag can be set.

Alternate version edit_specific_repeatable_subfield_content_with_regexp() is not described here to keep all documented functions using the same logic in arguments to pass.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to edit
• codes (list of str) : list of subfield codes to edit
• pattern (str) : regular expression matching pattern
• repl (str) : regular expression substitution expression

Function replace_repeatable_subf_content_not_matching_regexp_for_tag()

Replaces all subfields value with given codes for all fields with given tag if they do not match given regular expression. No flag are used and no flag can be set.

Alternate version replace_specific_repeatable_subfield_content_not_matching_regexp() is not described here to keep all documented functions using the same logic in arguments to pass.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to edit
• codes (list of str) : list of subfield codes to edit
• pattern (str) : regular expression matching pattern
• repl (str) : the replacement text to use

Function fix_7XX()

Change tags in 7XX fields to make sure that only 1 7X0 is in the record and there's at least one 7X0 if there are 7X1 or 7X2

Takes as argument :

• record (pymarc.record.Record)
• [Optionnal] prioritize_71X (bool, default to False) : prioritize 710 over 700

Merge fields

Function merge_all_fields_by_tag()

Merges all fields with given tag, sorting the subfields if wanted. Edits the record and returns the new field (pymarc.field.Field). Indicators used are those from the first field occurrence.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to merge
• [Optionnal] sort (list of str, default to no sort) : list of subfields codes to sort. See sort argument logic to see how to configure it.

Function merge_all_subfields_with_code()

Merges all subfields with given code in every field with given tag. The position of the first subfield will be kept.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to edit
• code (str) : the subfield code to merge
• separator (str) : the separtor to use between subfields

Split fields

Function split_tags_if_multiple_specific_subfield()

Splits all fields with given tag into multiple fields if the field has multiple subfields with given code. Every other subfield is copied into all created fields.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to split
• code (str) : the subfield code to check

Function split_merged_tags()

Splits all fields with given tag into multiple fields if there are multiple subfields with the same code. In case some fields sufields have less occurrence than other subfields, copies the first subfield occurence for this code.

• record (pymarc.record.Record)
• tag (str) : the fields tag to split

Delete data

Function delete_empty_subfields()

Deletes every empty subfields in whole the record.

Takes as argument : record (pymarc.record.Record)

Function delete_empty_fields()

Deletes every empty fields in whole the record.

Takes as argument : record (pymarc.record.Record)

Function delete_field_if_all_subfields_match_regexp()

For all fields with given tag, deletes the entire field if all subfields with given code match the given regular expression.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to delete
• code (str) : the subfield code to check
• pattern (str) : regular expression matching pattern
• [Optionnal] keep_if_no_subf (bool, default to True) : if no subfield has given code, should the field be kept

Function delete_multiple_subfield_for_tag()

For all fields with given tag, only keeps the first subfield with given code.

Takes as argument :

• record (pymarc.record.Record)
• tag (str) : the fields tag to edit
• code (str) : the subfield code to keep only once

Debugging

Function field_as_string()

Returns the field as a string in WinIBW (blank indicators are returned as #)

Takes as argument :

• field (pymarc.field.Field)

Function record_as_string()

Returns the record as a string in WinIBW (blank indicators are returned as #)

Takes as argument :

• record (pymarc.record.Record)