from typing import List, Optional, Union class Query: """ Query is used to build complex queries that have more parameters than just the query string. The query string is set in the constructor, and other options have setter functions. The setter functions return the query object, so they can be chained, i.e. `Query("foo").verbatim().filter(...)` etc. """ def __init__(self, query_string: str) -> None: """ Create a new query object. The query string is set in the constructor, and other options have setter functions. """ self._query_string: str = query_string self._offset: int = 0 self._num: int = 10 self._no_content: bool = False self._no_stopwords: bool = False self._fields: Optional[List[str]] = None self._verbatim: bool = False self._with_payloads: bool = False self._with_scores: bool = False self._scorer: Optional[str] = None self._filters: List = list() self._ids: Optional[List[str]] = None self._slop: int = -1 self._timeout: Optional[float] = None self._in_order: bool = False self._sortby: Optional[SortbyField] = None self._return_fields: List = [] self._summarize_fields: List = [] self._highlight_fields: List = [] self._language: Optional[str] = None self._expander: Optional[str] = None self._dialect: Optional[int] = None def query_string(self) -> str: """Return the query string of this query only.""" return self._query_string def limit_ids(self, *ids) -> "Query": """Limit the results to a specific set of pre-known document ids of any length.""" self._ids = ids return self def return_fields(self, *fields) -> "Query": """Add fields to return fields.""" self._return_fields += fields return self def return_field(self, field: str, as_field: Optional[str] = None) -> "Query": """Add field to return fields (Optional: add 'AS' name to the field).""" self._return_fields.append(field) if as_field is not None: self._return_fields += ("AS", as_field) return self def _mk_field_list(self, fields: List[str]) -> List: if not fields: return [] return [fields] if isinstance(fields, str) else list(fields) def summarize( self, fields: Optional[List] = None, context_len: Optional[int] = None, num_frags: Optional[int] = None, sep: Optional[str] = None, ) -> "Query": """ Return an abridged format of the field, containing only the segments of the field which contain the matching term(s). If `fields` is specified, then only the mentioned fields are summarized; otherwise all results are summarized. Server side defaults are used for each option (except `fields`) if not specified - **fields** List of fields to summarize. All fields are summarized if not specified - **context_len** Amount of context to include with each fragment - **num_frags** Number of fragments per document - **sep** Separator string to separate fragments """ args = ["SUMMARIZE"] fields = self._mk_field_list(fields) if fields: args += ["FIELDS", str(len(fields))] + fields if context_len is not None: args += ["LEN", str(context_len)] if num_frags is not None: args += ["FRAGS", str(num_frags)] if sep is not None: args += ["SEPARATOR", sep] self._summarize_fields = args return self def highlight( self, fields: Optional[List[str]] = None, tags: Optional[List[str]] = None ) -> None: """ Apply specified markup to matched term(s) within the returned field(s). - **fields** If specified then only those mentioned fields are highlighted, otherwise all fields are highlighted - **tags** A list of two strings to surround the match. """ args = ["HIGHLIGHT"] fields = self._mk_field_list(fields) if fields: args += ["FIELDS", str(len(fields))] + fields if tags: args += ["TAGS"] + list(tags) self._highlight_fields = args return self def language(self, language: str) -> "Query": """ Analyze the query as being in the specified language. :param language: The language (e.g. `chinese` or `english`) """ self._language = language return self def slop(self, slop: int) -> "Query": """Allow a maximum of N intervening non matched terms between phrase terms (0 means exact phrase). """ self._slop = slop return self def timeout(self, timeout: float) -> "Query": """overrides the timeout parameter of the module""" self._timeout = timeout return self def in_order(self) -> "Query": """ Match only documents where the query terms appear in the same order in the document. i.e. for the query "hello world", we do not match "world hello" """ self._in_order = True return self def scorer(self, scorer: str) -> "Query": """ Use a different scoring function to evaluate document relevance. Default is `TFIDF`. :param scorer: The scoring function to use (e.g. `TFIDF.DOCNORM` or `BM25`) """ self._scorer = scorer return self def get_args(self) -> List[str]: """Format the redis arguments for this query and return them.""" args = [self._query_string] args += self._get_args_tags() args += self._summarize_fields + self._highlight_fields args += ["LIMIT", self._offset, self._num] return args def _get_args_tags(self) -> List[str]: args = [] if self._no_content: args.append("NOCONTENT") if self._fields: args.append("INFIELDS") args.append(len(self._fields)) args += self._fields if self._verbatim: args.append("VERBATIM") if self._no_stopwords: args.append("NOSTOPWORDS") if self._filters: for flt in self._filters: if not isinstance(flt, Filter): raise AttributeError("Did not receive a Filter object.") args += flt.args if self._with_payloads: args.append("WITHPAYLOADS") if self._scorer: args += ["SCORER", self._scorer] if self._with_scores: args.append("WITHSCORES") if self._ids: args.append("INKEYS") args.append(len(self._ids)) args += self._ids if self._slop >= 0: args += ["SLOP", self._slop] if self._timeout is not None: args += ["TIMEOUT", self._timeout] if self._in_order: args.append("INORDER") if self._return_fields: args.append("RETURN") args.append(len(self._return_fields)) args += self._return_fields if self._sortby: if not isinstance(self._sortby, SortbyField): raise AttributeError("Did not receive a SortByField.") args.append("SORTBY") args += self._sortby.args if self._language: args += ["LANGUAGE", self._language] if self._expander: args += ["EXPANDER", self._expander] if self._dialect: args += ["DIALECT", self._dialect] return args def paging(self, offset: int, num: int) -> "Query": """ Set the paging for the query (defaults to 0..10). - **offset**: Paging offset for the results. Defaults to 0 - **num**: How many results do we want """ self._offset = offset self._num = num return self def verbatim(self) -> "Query": """Set the query to be verbatim, i.e. use no query expansion or stemming. """ self._verbatim = True return self def no_content(self) -> "Query": """Set the query to only return ids and not the document content.""" self._no_content = True return self def no_stopwords(self) -> "Query": """ Prevent the query from being filtered for stopwords. Only useful in very big queries that you are certain contain no stopwords. """ self._no_stopwords = True return self def with_payloads(self) -> "Query": """Ask the engine to return document payloads.""" self._with_payloads = True return self def with_scores(self) -> "Query": """Ask the engine to return document search scores.""" self._with_scores = True return self def limit_fields(self, *fields: List[str]) -> "Query": """ Limit the search to specific TEXT fields only. - **fields**: A list of strings, case sensitive field names from the defined schema. """ self._fields = fields return self def add_filter(self, flt: "Filter") -> "Query": """ Add a numeric or geo filter to the query. **Currently only one of each filter is supported by the engine** - **flt**: A NumericFilter or GeoFilter object, used on a corresponding field """ self._filters.append(flt) return self def sort_by(self, field: str, asc: bool = True) -> "Query": """ Add a sortby field to the query. - **field** - the name of the field to sort by - **asc** - when `True`, sorting will be done in asceding order """ self._sortby = SortbyField(field, asc) return self def expander(self, expander: str) -> "Query": """ Add a expander field to the query. - **expander** - the name of the expander """ self._expander = expander return self def dialect(self, dialect: int) -> "Query": """ Add a dialect field to the query. - **dialect** - dialect version to execute the query under """ self._dialect = dialect return self class Filter: def __init__(self, keyword: str, field: str, *args: List[str]) -> None: self.args = [keyword, field] + list(args) class NumericFilter(Filter): INF = "+inf" NEG_INF = "-inf" def __init__( self, field: str, minval: Union[int, str], maxval: Union[int, str], minExclusive: bool = False, maxExclusive: bool = False, ) -> None: args = [ minval if not minExclusive else f"({minval}", maxval if not maxExclusive else f"({maxval}", ] Filter.__init__(self, "FILTER", field, *args) class GeoFilter(Filter): METERS = "m" KILOMETERS = "km" FEET = "ft" MILES = "mi" def __init__( self, field: str, lon: float, lat: float, radius: float, unit: str = KILOMETERS ) -> None: Filter.__init__(self, "GEOFILTER", field, lon, lat, radius, unit) class SortbyField: def __init__(self, field: str, asc=True) -> None: self.args = [field, "ASC" if asc else "DESC"]