lib_solr.php

<?php

	#
	# $Id$
	#

	# This is *not* a general purpose wrapper library for talking to Solr.

	#################################################################

	loadlib("http");
	loadlib("solr_utils");

	#################################################################

	# Note: this doesn't do any magic with 'q' query parameters yet
	# so you'll need to do that before you get here

	function solr_select($params, $more=array()){

		# defaults (to do: spill)

		$page = isset($more['page']) ? max(1, $more['page']) : 1;
		$per_page = isset($more['per_page']) ? max(1, $more['per_page']) : $GLOBALS['cfg']['pagination_per_page'];

		$start = ($page - 1) * $per_page;
		$rows = $per_page;

		$params['rows'] = $rows;
		$params['start'] = $start;

		$rsp = _solr_select($params);

		if (! $rsp['ok']){
			return $rsp;
		}

		# pagination

		$total_count = $rsp['data']['response']['numFound'];
		$page_count = ceil($total_count / $per_page);
		$last_page_count = $total_count - (($page_count - 1) * $per_page);

		$rsp = array(
			'ok' => 1,
			'rows' => $rsp['data']['response']['docs'],
			'pagination' => array(
				'total_count' => $total_count,
				'page' => $page,
				'per_page' => $per_page,
				'page_count' => $page_count,
			)
		);

		# TO DO: put this someplace common (like not here or lib_db)

		if ($GLOBALS['cfg']['pagination_assign_smarty_variable']) {
			$GLOBALS['smarty']->assign('pagination', $rsp['pagination']);
			$GLOBALS['smarty']->register_function('pagination', 'smarty_function_pagination');
		}
		
		return $rsp;
	}

	#################################################################

	# https://wiki.apache.org/solr/SpatialSearch#QuickStart
	# http://e-mats.org/2011/12/solr-missing-geographic-distance-in-response-when-using-fl_dist_geodist/

	function solr_select_nearby($lat, $lon, $params=array(), $more=array()){

		$defaults = array(
			"d" => 1,
			"sfield" => "location",
			"sort" => "geodist() asc",
		);

		$more = array_merge($defaults, $more);

		if (! isset($params['q'])){

			$query = array(
				"*" => "*",
			);

			$q = solr_utils_hash2query($query, " AND ");
			$params['q'] = $q;
		}

		$params['fq'] = "{!geofilt}";
		$params['pt'] = "{$lat},{$lon}";
		$params['sfield'] = $more['sfield'];
		$params['d'] = $more['d'];
		$params['sort'] = $more['sort'];

		return solr_select($params, $more);
	}

	#################################################################

	# https://wiki.apache.org/solr/SimpleFacetParameters
	# https://wiki.apache.org/solr/SolrFacetingOverview

	function solr_facet($params, $more=array()){

		$params['rows'] = 0;
		$params['facet'] = "on";

		$params['facet.mincount'] = (isset($more['mincount'])) ? $more['mincount'] : 1;

		# TO DO: pagination...
		$params['facet.limit'] = -1;

		$rsp = _solr_select($params);

		if (! $rsp['ok']){
			return $rsp;
		}

		$facet = $params['facet.field'];

		$fields = $rsp['data']['facet_counts']['facet_fields'];
		$facets = _solr_facet_fields_to_hash($fields[$facet]);

		arsort($facets);

		return array(
			'ok' => 1,
			'facets' => $facets,
		);
	}

	#################################################################

	# https://wiki.apache.org/solr/SimpleFacetParameters#rangefaceting

	function solr_facet_range($params, $more=array()){

		$params['rows'] = 0;
		$params['facet'] = "on";

		$params['facet.mincount'] = (isset($more['mincount'])) ? $more['mincount'] : 1;

		# TO DO: pagination?

		$params['facet.range.other'] = 'all';

		$rsp = _solr_select($params);

		if (! $rsp['ok']){
			return $rsp;
		}

	 	# see above (solr_facet) for notes about multiple facets

		$facet = $params['facet.range'];

		$ranges = $rsp['data']['facet_counts']['facet_ranges'];
		$fields = $ranges[$facet];

		$facets = _solr_facet_fields_to_hash($fields['counts']);
		$details = array();

		foreach (array('gap', 'start', 'end', 'before', 'after', 'between') as $key){

			if (! isset($fields[$key])){
				continue;
			}

			$details[$key] = $fields[$key];
		}

		return array(
			'ok' => 1,
			$facet => $facets,
			'details' => $details,
		);

		return $rsp;
	}

	#################################################################

	# https://wiki.apache.org/solr/UpdateJSON

	function solr_add($docs, $more=array()){

		$url = $GLOBALS['cfg']['solr_endpoint'] . "update/json";

		$params = array(
			'commit' => 'true',
			'wt' => 'json',
		);

		$str_params = http_build_query($params);
		$url = implode("?", array($url, $str_params));

		$body = json_encode($docs);

		$headers = array(
			'Content-type' => 'application/json',
		);

		$http_rsp = http_post($url, $body, $headers);

		$rsp = _solr_parse_response($http_rsp);
		return $rsp;
	}

	#################################################################

	# TO DO: solr_update (this is more complicated than it seems...)

	#################################################################

	function solr_delete(){

		# please write me
	}

	#################################################################

	# this is called by both solr_select and solr_facet

	function _solr_select($params){

		$params['wt'] = 'json';

		$url = $GLOBALS['cfg']['solr_endpoint'] . "select/";
		$str_params = _solr_build_query($params, "stringify");

		$http_rsp = http_post($url, $str_params);
		return _solr_parse_response($http_rsp);
	}

	#################################################################

	function _solr_parse_response($http_rsp){

		if (! $http_rsp['ok']){
			return $http_rsp;
		}

		$json = json_decode($http_rsp['body'], "as a hash");

		if (! $json){
			return array(
				'ok' => 0,
				'error' => 'Failed to parse response',
			);
		}

		$rsp = array(
			'ok' => 1,
			'data' => $json,
		);

		return $rsp;
	}

	#################################################################

	function _solr_build_query(&$params, $stringify=0){

		$query = array();

		foreach ($params as $k => $v){

			$v = (is_array($v)) ? $v : array($v);

			foreach ($v as $_v){
			 	$query[] = "$k=" . urlencode($_v);
			}
		}

		if ($stringify){
			$query = implode("&", $query);
		}

		return $query;
	}

	#################################################################

	function _solr_facet_fields_to_hash(&$fields){

		$hash = array();

		$count_facet = count($fields);

		foreach (range(0, $count_facet, 2) as $i){

			if ($i == $count_facet){
				break;
			}

			$key = $fields[$i];
			$count = $fields[$i + 1];
			$hash[$key] = $count;
		}

		return $hash;
	}

	#################################################################
?>