httk.serve.optimade.backend.translation

Translation of OPTIMADE filter syntax trees into backend search expressions.

The generic translation is implemented in httk.store.query.optimade_filters; translate_filter() delegates to translate_filter_ast() and wraps its neutral FilterTranslationError failure categories into TranslatorError HTTP errors. format_value() and translate_filter_node() are thin OPTIMADE-side wrappers over the upstream functions.

Functions

format_value(fulltype, val[, allow_null])	Convert a filter value and translate neutral failures to HTTP errors.
translate_filter(filter_ast, entries, adapter[, sort])	Build one searcher per entry source, with the filter applied to each.
translate_filter_node(node, search_variable, entry, ...)	Translate one filter node against an OPTIMADE entry-info property mapping.

Module Contents

httk.serve.optimade.backend.translation.format_value(fulltype, val, allow_null=False)

Convert a filter value and translate neutral failures to HTTP errors.

Delegates to httk.store.query.optimade_filters.format_value() and raises TranslatorError for its neutral FilterTranslationError failures.

Parameters:

• fulltype (str) – Simplified OPTIMADE property type.

• val (tuple[Any, Ellipsis]) – Parsed filter values.

• allow_null (bool) – Allow a null value for the property.

Returns:

Backend-ready filter value.

Raises:

httk.serve.optimade.model.errors.TranslatorError – If the value cannot be translated.

Return type:

Any

httk.serve.optimade.backend.translation.translate_filter(filter_ast, entries, adapter, sort=None)

Build one searcher per entry source, with the filter applied to each.

Relationship-property filters (dotted identifiers over served entry types) are resolved through the adapter’s related-property resolver (built by _related_property_resolver), so filtering references.doi behaves exactly like filtering /references directly.

Parameters:

• filter_ast (httk.core.optimade.FilterAst | None) – Parsed filter, or None for an unfiltered query.

• entries (list[str]) – Entry endpoints to search.

• adapter (httk.serve.optimade.backend.adapter.BackendAdapter) – Backend adapter supplying sources and handlers.

• sort (collections.abc.Sequence[tuple[str, bool]] | None) – Response fields and descending flags for sorting.

Returns:

Source/searcher pairs with the filter and sort applied.

Raises:

httk.serve.optimade.model.errors.TranslatorError – If the filter cannot be translated.

Return type:

list[tuple[httk.serve.optimade.backend.adapter.EntrySource, httk.store.query.Searcher]]

httk.serve.optimade.backend.translation.translate_filter_node(node, search_variable, entry, entry_info, handlers, recognized_prefixes, served_entries=())

Translate one filter node against an OPTIMADE entry-info property mapping.

An OPTIMADE-side adaptation of translate_filter_ast(): entry_info maps property names to their property dictionaries (only their 'fulltype' keys are read) rather than straight to fulltypes, served_entries names the relationship targets, and failures surface as TranslatorError instead of the upstream neutral FilterTranslationError.

No related-property resolver is threaded through, so relationship-property filters other than <type>.id HAS ... raise a not-implemented (501) error. Use translate_filter() (which builds the resolver from its adapter) for full relationship-property filtering.

Parameters:

• node (httk.core.optimade.FilterAst) – Filter node to translate.

• search_variable (httk.store.query.SearchVariable) – Backend variable used by the expression.

• entry (str) – Entry endpoint being filtered.

• entry_info (collections.abc.Mapping[str, Any]) – Simplified property metadata for the entry.

• handlers (httk.store.query.optimade_filters.HandlerTable) – Property handlers used for translation.

• recognized_prefixes (tuple[str, Ellipsis]) – Property-definition prefixes accepted by the filter.

• served_entries (tuple[str, Ellipsis]) – Entry types available as relationship targets.

Returns:

Backend search expression.

Raises:

httk.serve.optimade.model.errors.TranslatorError – If the filter cannot be translated.

Return type:

httk.store.query.SearchExpression