def _parse_digital_forms(self, prop=DIGITAL_FORMS):
""" Concatenates a list of Digital Form data structures parsed from the metadata """
xpath_map = self._data_structures[prop]
# Parse base digital form fields: 'name', 'content', 'decompression', 'version', 'specification'
xpath_root = self._data_map['_digital_forms_root']
digital_forms = parse_complex_list(self._xml_tree, xpath_root, xpath_map, prop)
# Parse digital form transfer option fields: 'access_desc', 'access_instrs', 'network_resource'
xpath_root = self._data_map['_transfer_options_root']
transfer_opts = parse_complex_list(self._xml_tree, xpath_root, xpath_map, prop)
# Split out digital form content that has been appended to specifications
content_delim = _DIGITAL_FORMS_CONTENT_DELIM
for digital_form in digital_forms:
specs = reduce_value(digital_form['specification'])
specs = specs.splitlines() if isinstance(specs, string_types) else specs
specifications = wrap_value(s.strip() for s in specs)
digital_form['content'] = []
digital_form['specification'] = []
has_content = False
# For each specification, insert delim before appending content
for spec in specifications:
has_content = has_content or spec == content_delim
if not has_content:
digital_form['specification'].append(spec)
elif spec != content_delim:
digital_form['content'].append(spec)
# Reduce spec and content to single string values if possible
for form_prop in ('content', 'specification'):
digital_form[form_prop] = reduce_value(filter_empty(digital_form[form_prop], u''))
# Combine digital forms and transfer options into a single complex struct
df_len = len(digital_forms)
to_len = len(transfer_opts)
parsed_forms = []
for idx in xrange(0, max(df_len, to_len)):
digital_form = {}.fromkeys(_iso_definitions[prop], u'')
if idx < df_len:
digital_form.update(i for i in digital_forms[idx].items() if i[1])
if idx < to_len:
digital_form.update(i for i in transfer_opts[idx].items() if i[1])
if any(digital_form.values()):
parsed_forms.append(digital_form)
return get_default_for_complex(prop, parsed_forms)
def _update_property(tree_to_update, xpath_root, xpaths, prop, values):
"""
Default update operation for a single parser property. If xpaths contains one xpath,
then one element per value will be inserted at that location in the tree_to_update;
otherwise, the number of values must match the number of xpaths.
"""
# Inner function to update a specific XPATH with the values provided
def update_element(elem, idx, root, path, vals):
""" Internal helper function to encapsulate single item update """
has_root = bool(root and len(path) > len(root) and path.startswith(root))
path, attr = get_xpath_tuple(path) # 'path/@attr' to ('path', 'attr')
if attr:
removed = [get_element(elem, path)]
remove_element_attributes(removed[0], attr)
elif not has_root:
removed = wrap_value(remove_element(elem, path))
else:
path = get_xpath_branch(root, path)
removed = [] if idx != 0 else [remove_element(e, path, True) for e in get_elements(elem, root)]
if not vals:
return removed
items = []
for i, val in enumerate(wrap_value(vals)):
elem_to_update = elem
if has_root:
elem_to_update = insert_element(elem, (i + idx), root)
val = val.decode('utf-8') if not isinstance(val, string_types) else val
if not attr:
items.append(insert_element(elem_to_update, i, path, val))
else:
items.append(insert_element(elem_to_update, i, path, **{attr: val}))
return items
# Code to update each of the XPATHs with each of the values
xpaths = reduce_value(xpaths)
values = filter_empty(values)
if isinstance(xpaths, string_types):
return update_element(tree_to_update, 0, xpath_root, xpaths, values)
else:
each = []
for index, xpath in enumerate(xpaths):
value = values[index] if values else None
each.extend(update_element(tree_to_update, index, xpath_root, xpath, value))
return each
def _parse_digital_forms(self, prop=DIGITAL_FORMS):
""" Concatenates a list of Digital Form data structures parsed from the metadata """
xpath_map = self._data_structures[prop]
# Parse base digital form fields: 'name', 'content', 'decompression', 'version', 'specification'
xpath_root = self._data_map['_digital_forms_root']
digital_forms = parse_complex_list(self._xml_tree, xpath_root, xpath_map, prop)
# Parse digital form transfer option fields: 'access_desc', 'access_instrs', 'network_resource'
xpath_root = self._data_map['_transfer_options_root']
transfer_opts = parse_complex_list(self._xml_tree, xpath_root, xpath_map, prop)
# Split out digital form content that has been appended to specifications
content_delim = _DIGITAL_FORMS_CONTENT_DELIM
for digital_form in digital_forms:
specs = reduce_value(digital_form['specification'])
specs = specs.splitlines() if isinstance(specs, string_types) else specs
specifications = wrap_value(s.strip() for s in specs)
digital_form['content'] = []
digital_form['specification'] = []
has_content = False
# For each specification, insert delim before appending content
for spec in specifications:
has_content = has_content or spec == content_delim
if not has_content:
digital_form['specification'].append(spec)
elif spec != content_delim:
digital_form['content'].append(spec)
# Reduce spec and content to single string values if possible
for form_prop in ('content', 'specification'):
digital_form[form_prop] = reduce_value(filter_empty(digital_form[form_prop], u''))
# Combine digital forms and transfer options into a single complex struct
df_len = len(digital_forms)
to_len = len(transfer_opts)
parsed_forms = []
for idx in xrange(0, max(df_len, to_len)):
digital_form = {}.fromkeys(_iso_definitions[prop], u'')
if idx < df_len:
digital_form.update(i for i in digital_forms[idx].items() if i[1])
if idx < to_len:
digital_form.update(i for i in transfer_opts[idx].items() if i[1])
if any(digital_form.values()):
parsed_forms.append(digital_form)
return get_default_for_complex(prop, parsed_forms)
def _update_property(tree_to_update, xpath_root, xpaths, values):
"""
Default update operation for a single parser property. If xpaths contains one xpath,
then one element per value will be inserted at that location in the tree_to_update;
otherwise, the number of values must match the number of xpaths.
"""
# Inner function to update a specific XPATH with the values provided
def update_element(elem, idx, root, path, vals):
""" Internal helper function to encapsulate single item update """
has_root = bool(root and len(path) > len(root)
and path.startswith(root))
path, attr = get_xpath_tuple(path) # 'path/@attr' to ('path', 'attr')
if attr:
removed = [get_element(elem, path)]
remove_element_attributes(removed[0], attr)
elif not has_root:
removed = wrap_value(remove_element(elem, path))
else:
path = get_xpath_branch(root, path)
removed = [] if idx != 0 else [
remove_element(e, path, True)
for e in get_elements(elem, root)
]
if not vals:
return removed
items = []
for i, val in enumerate(wrap_value(vals)):
elem_to_update = elem
if has_root:
elem_to_update = insert_element(elem, (i + idx), root)
val = val.decode('utf-8') if not isinstance(val,
string_types) else val
if not attr:
items.append(insert_element(elem_to_update, i, path, val))
elif path:
items.append(
insert_element(elem_to_update, i, path, **{attr: val}))
else:
set_element_attributes(elem_to_update, **{attr: val})
items.append(elem_to_update)
return items
# Code to update each of the XPATHs with each of the values
xpaths = reduce_value(xpaths)
values = filter_empty(values)
if isinstance(xpaths, string_types):
return update_element(tree_to_update, 0, xpath_root, xpaths, values)
else:
each = []
for index, xpath in enumerate(xpaths):
value = values[index] if values else None
each.extend(
update_element(tree_to_update, index, xpath_root, xpath,
value))
return each
