HedSchema¶

class HedSchema[source]: A HED schema suitable for processing.

Methods

`HedSchema.__init__`()	Constructor for the HedSchema class.
`HedSchema.can_save`()	Returns if it's legal to save this schema.
`HedSchema.check_compliance`([...])	Check for HED3 compliance of this schema.
`HedSchema.finalize_dictionaries`()	Call to finish loading.
`HedSchema.find_tag_entry`(tag[, schema_namespace])	Find the schema entry for a given source tag.
`HedSchema.get_all_schema_tags`([return_last_term])	Get a list of all hed terms from the schema.
`HedSchema.get_all_tag_attributes`(tag_name[, ...])	Gather all attributes for a given tag name.
`HedSchema.get_as_mediawiki_string`([save_merged])	Return the schema to a mediawiki string.
`HedSchema.get_as_owl_string`([save_merged, ...])	Return the schema to a mediawiki string.
`HedSchema.get_as_xml_string`([save_merged])	Return the schema to an XML string.
`HedSchema.get_desc_iter`()	Return an iterator over all the descriptions.
`HedSchema.get_formatted_version`()	The HED version string including namespace and library name if any of this schema.
`HedSchema.get_save_header_attributes`([...])	returns the attributes that should be saved.
`HedSchema.get_schema_versions`()	A list of HED version strings including namespace and library name if any of this schema.
`HedSchema.get_tag_attribute_names`()	Return a dict of all allowed tag attributes.
`HedSchema.get_tag_description`(tag_name[, ...])	Return the description associated with the tag.
`HedSchema.get_tag_entry`(name[, key_class, ...])	Return the schema entry for this tag, if one exists.
`HedSchema.get_tags_with_attribute`(attribute)	Return tag entries with the given attribute.
`HedSchema.get_unknown_attributes`()	Retrieve the current list of unknown attributes.
`HedSchema.has_duplicates`()	Returns the first duplicate tag/unit/etc if any section has a duplicate name
`HedSchema.save_as_mediawiki`(filename[, ...])	Save as mediawiki to a file.
`HedSchema.save_as_owl`(filename[, ...])	Save as json to a file.
`HedSchema.save_as_xml`(filename[, save_merged])	Save as XML to a file.
`HedSchema.schema_for_namespace`(namespace)	Return HedSchema object for this namespace.
`HedSchema.set_schema_prefix`(schema_namespace)	Set library namespace associated for this schema.

Attributes

`HedSchema.attributes`	Return the attributes schema section.
`HedSchema.library`	The name of this library schema if one exists.
`HedSchema.merged`	Returns if this schema was loaded from a merged file
`HedSchema.name`	User provided name for this schema, defaults to filename or version if no name provided.
`HedSchema.properties`	Return the properties schema section.
`HedSchema.schema_namespace`	Returns the schema namespace prefix
`HedSchema.tags`	Return the tag schema section.
`HedSchema.unit_classes`	Return the unit classes schema section.
`HedSchema.unit_modifiers`	Return the modifiers classes schema section
`HedSchema.units`	Return the unit schema section.
`HedSchema.valid_prefixes`	Return a list of all prefixes this schema will accept
`HedSchema.value_classes`	Return the value classes schema section.
`HedSchema.version`	The complete schema version, including prefix and library name(if applicable)
`HedSchema.version_number`	The HED version of this schema.
`HedSchema.with_standard`	The version of the base schema this is extended from, if it exists.

HedSchema.__init__()[source]¶

Constructor for the HedSchema class.

A HedSchema can be used for validation, checking tag attributes, parsing tags, etc.

HedSchema.can_save()[source]¶

Returns if it’s legal to save this schema.

You cannot save schemas loaded as merged from multiple library schemas.

Returns:: True if this can be saved
Return type:: bool

HedSchema.check_compliance(check_for_warnings=True, name=None, error_handler=None)[source]¶

Check for HED3 compliance of this schema.

Parameters:

check_for_warnings (bool) – If True, checks for formatting issues like invalid characters, capitalization.
name (str) – If present, use as the filename for context, rather than using the actual filename. Useful for temp filenames when supporting web services.
error_handler (ErrorHandler or None) – Used to report errors. Uses a default one if none passed in.

Returns:

A list of all warnings and errors found in the file. Each issue is a dictionary.

Return type:

list

HedSchema.finalize_dictionaries()[source]¶: Call to finish loading.

HedSchema.find_tag_entry(tag, schema_namespace='')[source]¶

Find the schema entry for a given source tag.

Parameters:

tag (str, HedTag) – Any form of tag to look up. Can have an extension, value, etc.
schema_namespace (str) – The schema namespace of the tag, if any.

Returns:

The located tag entry for this tag. str: The remainder of the tag that isn’t part of the base tag. list: A list of errors while converting.

Return type:

HedTagEntry

Notes

Works left to right (which is mostly relevant for errors).

HedSchema.get_all_schema_tags(return_last_term=False)[source]¶

Get a list of all hed terms from the schema.

Returns:: A list of all terms(short tags) from the schema.
Return type:: list

Notes

Compatible with Hed2 or Hed3.

HedSchema.get_all_tag_attributes(tag_name, key_class=HedSectionKey.Tags)[source]¶

Gather all attributes for a given tag name.

Parameters:

tag_name (str) – The name of the tag to check.
key_class (str) – The type of attributes requested. e.g. Tag, Units, Unit modifiers, or attributes.

Returns:

A dictionary of attribute name and attribute value.

Return type:

dict

Notes

If keys is None, gets all normal hed tag attributes.

HedSchema.get_as_mediawiki_string(save_merged=False)[source]¶

Return the schema to a mediawiki string.

Parameters:: save_merged (bool) – If True, this will save the schema as a merged schema if it is a “withStandard” schema. If it is not a “withStandard” schema, this setting has no effect.
Returns:: The schema as a string in mediawiki format.
Return type:: str

HedSchema.get_as_owl_string(save_merged=False, file_format='owl')[source]¶

Return the schema to a mediawiki string.

Parameters:

save_merged (bool) – If True, this will save the schema as a merged schema if it is a “withStandard” schema. If it is not a “withStandard” schema, this setting has no effect.
file_format (str or None) – Override format from filename extension. Accepts any value rdflib accepts(We fully support “turtle”, “xml”(“owl” also accepted) and “json-ld”). Other values should work, but aren’t as fully supported.

Returns:

The schema as a string in mediawiki format.

Return type:

str

Raises:

rdflib.plugin.PluginException –

Invalid format of file_format. Make sure you use a supported RDF format.

HedSchema.get_as_xml_string(save_merged=True)[source]¶

Return the schema to an XML string.

Parameters:

save_merged (bool) –
True (If) –
schema. (this will save the schema as a merged schema if it is a "withStandard") –
schema (If it is not a "withStandard") –
effect. (this setting has no) –

Returns:

Return the schema as an XML string.

Return type:

str

HedSchema.get_desc_iter()[source]¶

Return an iterator over all the descriptions.

Yields:: tuple – - str: The tag node name. - str: The description associated with the node.

HedSchema.get_formatted_version()[source]¶

The HED version string including namespace and library name if any of this schema.

Returns:: A json formatted string of the complete version of this schema including library name and namespace.
Return type:: str

HedSchema.get_save_header_attributes(save_merged=False)[source]¶: returns the attributes that should be saved.

HedSchema.get_schema_versions()[source]¶

A list of HED version strings including namespace and library name if any of this schema.

Returns:: The complete version of this schema including library name and namespace.
Return type:: list

HedSchema.get_tag_attribute_names()[source]¶

Return a dict of all allowed tag attributes.

Returns:: A dictionary whose keys are attribute names and values are HedSchemaEntry object.
Return type:: dict

HedSchema.get_tag_description(tag_name, key_class=HedSectionKey.Tags)[source]¶

Return the description associated with the tag.

Parameters:

tag_name (str) – A hed tag name(or unit/unit modifier etc) with proper capitalization.
key_class (str) – A string indicating type of description (e.g. All tags, Units, Unit modifier). The default is HedSectionKey.Tags.

Returns:

A description of the specified tag.

Return type:

str

HedSchema.get_tag_entry(name, key_class=HedSectionKey.Tags, schema_namespace='')[source]¶

Return the schema entry for this tag, if one exists.

Parameters:

name (str) – Any form of basic tag(or other section entry) to look up. This will not handle extensions or similar. If this is a tag, it can have a schema namespace, but it’s not required
key_class (HedSectionKey or str) – The type of entry to return.
schema_namespace (str) – Only used on Tags. If incorrect, will return None.

Returns:

The schema entry for the given tag.

Return type:

HedSchemaEntry

HedSchema.get_tags_with_attribute(attribute, key_class=HedSectionKey.Tags)[source]¶

Return tag entries with the given attribute.

Parameters:

attribute (str) – A tag attribute. Eg HedKey.ExtensionAllowed
key_class (HedSectionKey) – The HedSectionKey for the section to retrieve from.

Returns:

A list of all tags with this attribute.

Return type:

list

Notes

The result is cached so will be fast after first call.

HedSchema.get_unknown_attributes()[source]¶

Retrieve the current list of unknown attributes.

Returns:: The keys are attribute names and the values are lists of tags with this attribute.
Return type:: dict

Notes

This includes attributes found in the wrong section for example unitClass attribute found on a Tag.
The return tag list is in long form.

HedSchema.has_duplicates()[source]¶: Returns the first duplicate tag/unit/etc if any section has a duplicate name

HedSchema.save_as_mediawiki(filename, save_merged=False)[source]¶

Save as mediawiki to a file.

filename: str: save location
save_merged: bool: If True, this will save the schema as a merged schema if it is a “withStandard” schema. If it is not a “withStandard” schema, this setting has no effect.

Raises:

OSError –

File cannot be saved for some reason.

HedSchema.save_as_owl(filename, save_merged=False, file_format=None)[source]¶

Save as json to a file.

filename: str: Save the file here
save_merged: bool: If True, this will save the schema as a merged schema if it is a “withStandard” schema. If it is not a “withStandard” schema, this setting has no effect.
file_format(str or None): Required for owl formatted files other than the following:: .ttl: turtle .owl: xml .json-ld: json-ld

Raises:

OSError –
- File cannot be saved for some reason
rdflib.plugin.PluginException –
- Invalid format of file_format. Make sure you use a supported RDF format.

HedSchema.save_as_xml(filename, save_merged=True)[source]¶

Save as XML to a file.

filename: str: save location
save_merged: bool: If true, this will save the schema as a merged schema if it is a “withStandard” schema. If it is not a “withStandard” schema, this setting has no effect.

Raises:

OSError –

File cannot be saved for some reason

HedSchema.schema_for_namespace(namespace)[source]¶

Return HedSchema object for this namespace.

Parameters:: namespace (str) – The schema library name namespace.
Returns:: The HED schema object for this schema.
Return type:: HedSchema

HedSchema.set_schema_prefix(schema_namespace)[source]¶

Set library namespace associated for this schema.

Parameters:

schema_namespace (str) – Should be empty, or end with a colon.(Colon will be automated added if missing).

Raises:

HedFileError –

The prefix is invalid

HedSchema.attributes¶

Return the attributes schema section.

Returns:: The attributes section.
Return type:: HedSchemaSection

HedSchema.library¶

The name of this library schema if one exists.

Returns:: Library name if any.
Return type:: str

HedSchema.merged¶

Returns if this schema was loaded from a merged file

Returns:: True if file was loaded from a merged file
Return type:: bool

HedSchema.name¶: User provided name for this schema, defaults to filename or version if no name provided.

HedSchema.properties¶

Return the properties schema section.

Returns:: The properties section.
Return type:: HedSchemaSection

HedSchema.schema_namespace¶: Returns the schema namespace prefix

HedSchema.tags¶

Return the tag schema section.

Returns:: The tag section.
Return type:: HedSchemaTagSection

HedSchema.unit_classes¶

Return the unit classes schema section.

Returns:: The unit classes section.
Return type:: HedSchemaUnitClassSection

HedSchema.unit_modifiers¶

Return the modifiers classes schema section

Returns:: The unit modifiers section.
Return type:: HedSchemaSection

HedSchema.units¶

Return the unit schema section.

Returns:: The unit section.
Return type:: HedSchemaSection

HedSchema.valid_prefixes¶

Return a list of all prefixes this schema will accept

Returns:: A list of valid tag prefixes for this schema.
Return type:: list

Notes

The return value is always length 1 if using a HedSchema.

HedSchema.value_classes¶

Return the value classes schema section.

Returns:: The value classes section.
Return type:: HedSchemaSection

HedSchema.version¶: The complete schema version, including prefix and library name(if applicable)

HedSchema.version_number¶

The HED version of this schema.

Returns:: The version of this schema.
Return type:: str

HedSchema.with_standard¶

The version of the base schema this is extended from, if it exists.

Returns:: HED version or “”
Return type:: str