.. _engines-dev: =============== Engine Overview =============== .. _metasearch-engine: https://en.wikipedia.org/wiki/Metasearch_engine .. sidebar:: Further reading .. - :ref:`configured engines` - :ref:`settings engine` .. contents:: :depth: 3 :backlinks: entry SearXNG is a metasearch-engine_, so it uses different search engines to provide better results. Because there is no general search API which could be used for every search engine, an adapter has to be built between SearXNG and the external search engines. Adapters are stored under the folder :origin:`searx/engines`. .. _general engine configuration: General Engine Configuration ============================ It is required to tell SearXNG the type of results the engine provides. The arguments can be set in the engine file or in the settings file (normally ``settings.yml``). The arguments in the settings file override the ones in the engine file. It does not matter if an option is stored in the engine file or in the settings. However, the standard way is the following: .. _engine file: Engine File ----------- .. table:: Common options in the engine module :width: 100% ======================= =========== ======================================================== argument type information ======================= =========== ======================================================== categories list pages, in which the engine is working paging boolean support multiple pages time_range_support boolean support search time range engine_type str - ``online`` :ref:`[ref] ` by default, other possibles values are: - ``offline`` :ref:`[ref] ` - ``online_dictionary`` - ``online_currency`` ======================= =========== ======================================================== .. _engine settings: Engine ``settings.yml`` ----------------------- For a more detailed description, see :ref:`settings engine` in the :ref:`settings.yml`. .. table:: Common options in the engine setup (``settings.yml``) :width: 100% ======================= =========== ================================================== argument type information ======================= =========== ================================================== name string name of search-engine engine string name of searxng-engine (file name without ``.py``) enable_http bool enable HTTP (by default only HTTPS is enabled). shortcut string shortcut of search-engine timeout string specific timeout for search-engine display_error_messages boolean display error messages on the web UI proxies dict set proxies for a specific engine (e.g. ``proxies : {http: socks5://proxy:port, https: socks5://proxy:port}``) ======================= =========== ================================================== .. _engine overrides: Overrides --------- A few of the options have default values in the namespace of engine's python modul, but are often overwritten by the settings. If ``None`` is assigned to an option in the engine file, it has to be redefined in the settings, otherwise SearXNG will not start with that engine (global names with a leading underline can be ``None``). Here is an very simple example of the global names in the namespace of engine's module: .. code:: python # engine dependent config categories = ['general'] paging = True _non_overwritten_global = 'foo' .. table:: The naming of overrides is arbitrary / recommended overrides are: :width: 100% ======================= =========== =========================================== argument type information ======================= =========== =========================================== base_url string base-url, can be overwritten to use same engine on other URL number_of_results int maximum number of results per request language string ISO code of language and country like en_US api_key string api-key if required by engine ======================= =========== =========================================== .. _engine request: Making a Request ================ To perform a search an URL have to be specified. In addition to specifying an URL, arguments can be passed to the query. .. _engine request arguments: Passed Arguments (request) -------------------------- These arguments can be used to construct the search query. Furthermore, parameters with default value can be redefined for special purposes. .. table:: If the ``engine_type`` is ``online`` :width: 100% ====================== ============== ======================================================================== argument type default-value, information ====================== ============== ======================================================================== url str ``''`` method str ``'GET'`` headers set ``{}`` data set ``{}`` cookies set ``{}`` verify bool ``True`` headers.User-Agent str a random User-Agent category str current category, like ``'general'`` safesearch int ``0``, between ``0`` and ``2`` (normal, moderate, strict) time_range Optional[str] ``None``, can be ``day``, ``week``, ``month``, ``year`` pageno int current pagenumber language str specific language code like ``'en_US'``, or ``'all'`` if unspecified ====================== ============== ======================================================================== .. table:: If the ``engine_type`` is ``online_dictionary``, in addition to the ``online`` arguments: :width: 100% ====================== ============== ======================================================================== argument type default-value, information ====================== ============== ======================================================================== from_lang str specific language code like ``'en_US'`` to_lang str specific language code like ``'en_US'`` query str the text query without the languages ====================== ============== ======================================================================== .. table:: If the ``engine_type`` is ``online_currency```, in addition to the ``online`` arguments: :width: 100% ====================== ============== ======================================================================== argument type default-value, information ====================== ============== ======================================================================== amount float the amount to convert from str ISO 4217 code to str ISO 4217 code from_name str currency name to_name str currency name ====================== ============== ======================================================================== Specify Request --------------- The function :py:func:`def request(query, params): ` always returns the ``params`` variable, the following parameters can be used to specify a search request: .. table:: :width: 100% =================== =========== ========================================================================== argument type information =================== =========== ========================================================================== url str requested url method str HTTP request method headers set HTTP header information data set HTTP data information cookies set HTTP cookies verify bool Performing SSL-Validity check allow_redirects bool Follow redirects max_redirects int maximum redirects, hard limit soft_max_redirects int maximum redirects, soft limit. Record an error but don't stop the engine raise_for_httperror bool True by default: raise an exception if the HTTP code of response is >= 300 =================== =========== ========================================================================== .. _engine results: .. _engine media types: Media Types =========== Each result item of an engine can be of different media-types. Currently the following media-types are supported. To set another media-type as ``default``, the parameter ``template`` must be set to the desired type. .. table:: Parameter of the **default** media type: :width: 100% ========================= ===================================================== result-parameter information ========================= ===================================================== url string, url of the result title string, title of the result content string, general result-text publishedDate :py:class:`datetime.datetime`, time of publish ========================= ===================================================== .. table:: Parameter of the **images** media type: :width: 100% ========================= ===================================================== result-parameter information ------------------------- ----------------------------------------------------- template is set to ``images.html`` ========================= ===================================================== url string, url to the result site title string, title of the result *(partly implemented)* content *(partly implemented)* publishedDate :py:class:`datetime.datetime`, time of publish *(partly implemented)* img\_src string, url to the result image thumbnail\_src string, url to a small-preview image ========================= ===================================================== .. table:: Parameter of the **videos** media type: :width: 100% ========================= ===================================================== result-parameter information ------------------------- ----------------------------------------------------- template is set to ``videos.html`` ========================= ===================================================== url string, url of the result title string, title of the result content *(not implemented yet)* publishedDate :py:class:`datetime.datetime`, time of publish thumbnail string, url to a small-preview image ========================= ===================================================== .. _magnetlink: https://en.wikipedia.org/wiki/Magnet_URI_scheme .. table:: Parameter of the **torrent** media type: :width: 100% ========================= ===================================================== result-parameter information ------------------------- ----------------------------------------------------- template is set to ``torrent.html`` ========================= ===================================================== url string, url of the result title string, title of the result content string, general result-text publishedDate :py:class:`datetime.datetime`, time of publish *(not implemented yet)* seed int, number of seeder leech int, number of leecher filesize int, size of file in bytes files int, number of files magnetlink string, magnetlink_ of the result torrentfile string, torrentfile of the result ========================= ===================================================== .. table:: Parameter of the **map** media type: :width: 100% ========================= ===================================================== result-parameter information ------------------------- ----------------------------------------------------- template is set to ``map.html`` ========================= ===================================================== url string, url of the result title string, title of the result content string, general result-text publishedDate :py:class:`datetime.datetime`, time of publish latitude latitude of result (in decimal format) longitude longitude of result (in decimal format) boundingbox boundingbox of result (array of 4. values ``[lat-min, lat-max, lon-min, lon-max]``) geojson geojson of result (https://geojson.org/) osm.type type of osm-object (if OSM-Result) osm.id id of osm-object (if OSM-Result) address.name name of object address.road street name of object address.house_number house number of object address.locality city, place of object address.postcode postcode of object address.country country of object ========================= ===================================================== .. _BibTeX format: https://www.bibtex.com/g/bibtex-format/ .. _BibTeX field types: https://en.wikipedia.org/wiki/BibTeX#Field_types .. list-table:: Parameter of the **paper** media type / see `BibTeX field types`_ and `BibTeX format`_ :header-rows: 2 :width: 100% * - result-parameter - Python type - information * - template - :py:class:`str` - is set to ``paper.html`` * - title - :py:class:`str` - title of the result * - content - :py:class:`str` - abstract * - comments - :py:class:`str` - free text display in italic below the content * - tags - :py:class:`List `\ [\ :py:class:`str`\ ] - free tag list * - publishedDate - :py:class:`datetime ` - last publication date * - type - :py:class:`str` - short description of medium type, e.g. *book*, *pdf* or *html* ... * - authors - :py:class:`List `\ [\ :py:class:`str`\ ] - list of authors of the work (authors with a "s") * - editor - :py:class:`str` - list of editors of a book * - publisher - :py:class:`str` - name of the publisher * - journal - :py:class:`str` - name of the journal or magazine the article was published in * - volume - :py:class:`str` - volume number * - pages - :py:class:`str` - page range where the article is * - number - :py:class:`str` - number of the report or the issue number for a journal article * - doi - :py:class:`str` - DOI number (like ``10.1038/d41586-018-07848-2``) * - issn - :py:class:`str` - ISSN number like ``1476-4687`` * - isbn - :py:class:`str` - ISBN number like ``9780201896831`` * - pdf_url - :py:class:`str` - URL to the full article, the PDF version * - html_url - :py:class:`str` - URL to full article, HTML version