[PATCH] RPC: Allow to search packages by "*depends" fields

[Baptiste Jonglez]

From: Baptiste Jonglez <git at bitsofnetworks.org>

It is now possible to search for packages that depend on a given package,
for instance:

    /rpc/?v=5&type=search&by=depends&arg=ocaml

It is similarly possible to match on "makedepends", "checkdepends" and
"optdepends".

Signed-off-by: Baptiste Jonglez <git at bitsofnetworks.org>
---
 doc/rpc.txt               |  8 +++++++-
 web/lib/aurjson.class.php | 33 +++++++++++++++++++++++++++++----
 2 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/doc/rpc.txt b/doc/rpc.txt
index f353ff0..3148ebe 100644
--- a/doc/rpc.txt
+++ b/doc/rpc.txt
@@ -11,6 +11,10 @@ search argument and _field_ is one of the following values:
 * `name` (search by package name only)
 * `name-desc` (search by package name and description)
 * `maintainer` (search by package maintainer)
+* `depends` (search for packages that depend on _keywords_)
+* `makedepends` (search for packages that makedepend on _keywords_)
+* `optdepends` (search for packages that optdepend on _keywords_)
+* `checkdepends` (search for packages that checkdepend on _keywords_)
 
 The _by_ parameter can be skipped and defaults to `name-desc`.
 
@@ -30,7 +34,9 @@ Examples
 `search`::
   `/rpc/?v=5&type=search&arg=foobar`
 `search` by maintainer::
-  `/rpc/?v=5&type=search&search_by=maintainer&arg=john`
+  `/rpc/?v=5&type=search&by=maintainer&arg=john`
+`search` packages that have _boost_ as `makedepends`::
+  `/rpc/?v=5&type=search&by=makedepends&arg=boost`
 `search` with callback::
   `/rpc/?v=5&type=search&arg=foobar&callback=jsonp1192244621103`
 `info`::
diff --git a/web/lib/aurjson.class.php b/web/lib/aurjson.class.php
index 9eeaafd..30bdc89 100644
--- a/web/lib/aurjson.class.php
+++ b/web/lib/aurjson.class.php
@@ -17,7 +17,8 @@ class AurJSON {
 		'suggest-pkgbase', 'get-comment-form'
 	);
 	private static $exposed_fields = array(
-		'name', 'name-desc', 'maintainer'
+		'name', 'name-desc', 'maintainer',
+		'depends', 'makedepends', 'checkdepends', 'optdepends'
 	);
 	private static $fields_v1 = array(
 		'Packages.ID', 'Packages.Name',
@@ -243,16 +244,27 @@ class AurJSON {
 
 	/*
 	 * Retrieve package information (used in info, multiinfo, search and
-	 * msearch requests).
+	 * depends requests).
 	 *
 	 * @param $type The request type.
 	 * @param $where_condition An SQL WHERE-condition to filter packages.
+	 * @param $join_depends Whether to add a SQL JOIN on the PackageDepends table.
+	 *        It will produce duplicate packages unless $where_condition filters
+	 *        the result appropriately.
 	 *
 	 * @return mixed Returns an array of package matches.
 	 */
-	private function process_query($type, $where_condition) {
+	private function process_query($type, $where_condition, $join_depends=false) {
 		$max_results = config_get_int('options', 'max_rpc_results');
 
+		$additional_joins = "";
+		if ($join_depends) {
+			$additional_joins .= "LEFT JOIN PackageDepends " .
+					"ON Packages.ID = PackageDepends.PackageID " .
+					"LEFT JOIN DependencyTypes " .
+					"ON PackageDepends.DepTypeID = DependencyTypes.ID";
+		}
+
 		if ($this->version == 1) {
 			$fields = implode(',', self::$fields_v1);
 			$query = "SELECT {$fields} " .
@@ -264,6 +276,7 @@ class AurJSON {
 				"ON PackageLicenses.PackageID = Packages.ID " .
 				"LEFT JOIN Licenses " .
 				"ON Licenses.ID = PackageLicenses.LicenseID " .
+				"${additional_joins} " .
 				"WHERE ${where_condition} " .
 				"AND PackageBases.PackagerUID IS NOT NULL " .
 				"LIMIT $max_results";
@@ -278,6 +291,7 @@ class AurJSON {
 				"ON PackageBases.ID = Packages.PackageBaseID " .
 				"LEFT JOIN Users " .
 				"ON PackageBases.MaintainerUID = Users.ID " .
+				"${additional_joins} " .
 				"WHERE ${where_condition} " .
 				"AND PackageBases.PackagerUID IS NOT NULL " .
 				"LIMIT $max_results";
@@ -380,6 +394,7 @@ class AurJSON {
 	 * @return mixed Returns an array of package matches.
 	 */
 	private function search($http_data) {
+		$join_depends = false;
 		$keyword_string = $http_data['arg'];
 
 		if (isset($http_data['by'])) {
@@ -407,9 +422,19 @@ class AurJSON {
 				$keyword_string = $this->dbh->quote($keyword_string);
 				$where_condition = "Users.Username = $keyword_string ";
 			}
+		} else if (in_array($search_by, ['depends', 'makedepends', 'checkdepends', 'optdepends'])) {
+			if (empty($keyword_string)) {
+				return $this->json_error('Query arg is empty.');
+			} else {
+				$keyword_string = $this->dbh->quote($keyword_string);
+				$search_string = $this->dbh->quote($search_by);
+				$where_condition = "PackageDepends.DepName = $keyword_string AND ";
+				$where_condition .= "DependencyTypes.Name = $search_string";
+				$join_depends = true;
+			}
 		}
 
-		return $this->process_query('search', $where_condition);
+		return $this->process_query('search', $where_condition, $join_depends);
 	}
 
 	/*
-- 
2.16.1