Make PG pool size configurable

t-rex-core/src/datasource/postgis_ds.rs

@@ -200,6 +200,7 @@ pub struct SqlQuery {
 #[derive(Clone)]
 pub struct PostgisDatasource {
     pub connection_url: String,
+    pub pool_size: Option<u16>,
     conn_pool: Option<r2d2::Pool<PostgresConnectionManager>>,
     // Queries for all layers and zoom levels
     queries: BTreeMap<String, BTreeMap<u8, SqlQuery>>,
@@ -247,9 +248,10 @@ impl SqlQuery {
 }
 
 impl PostgisDatasource {
-    pub fn new(connection_url: &str) -> PostgisDatasource {
+    pub fn new(connection_url: &str, pool_size: Option<u16>) -> PostgisDatasource {
         PostgisDatasource {
             connection_url: connection_url.to_string(),
+            pool_size,
             conn_pool: None,
             queries: BTreeMap::new(),
         }
@@ -611,12 +613,12 @@ impl PostgisDatasource {
 impl DatasourceType for PostgisDatasource {
     /// New instance with connected pool
     fn connected(&self) -> PostgisDatasource {
-        let pool_size = 10; //FIXME: make configurable
-                            // Emulate TlsMode::Allow (https://github.com/sfackler/rust-postgres/issues/278)
+        // Emulate TlsMode::Allow (https://github.com/sfackler/rust-postgres/issues/278)
         let manager =
             PostgresConnectionManager::new(self.connection_url.as_ref(), TlsMode::None).unwrap();
+        let pool_size = self.pool_size.unwrap_or(8); // TODO: use number of workers as default pool size
         let pool = r2d2::Pool::builder()
-            .max_size(pool_size)
+            .max_size(pool_size as u32)
             .build(manager)
             .or_else(|e| match e.description() {
                 "unable to initialize connections" => {
@@ -627,13 +629,16 @@ impl DatasourceType for PostgisDatasource {
                         TlsMode::Require(Box::new(negotiator)),
                     )
                     .unwrap();
-                    r2d2::Pool::builder().max_size(pool_size).build(manager)
+                    r2d2::Pool::builder()
+                        .max_size(pool_size as u32)
+                        .build(manager)
                 }
                 _ => Err(e),
             })
             .unwrap();
         PostgisDatasource {
             connection_url: self.connection_url.clone(),
+            pool_size: Some(pool_size),
             conn_pool: Some(pool),
             queries: BTreeMap::new(),
         }
@@ -868,9 +873,12 @@ impl<'a> Config<'a, DatasourceCfg> for PostgisDatasource {
     fn from_config(ds_cfg: &DatasourceCfg) -> Result<Self, String> {
         if let Ok(url) = env::var("TREX_DATASOURCE_URL") {
             // FIXME: this overwrites *all* PostGIS connections instead of a specific one
-            Ok(PostgisDatasource::new(url.as_str()))
+            Ok(PostgisDatasource::new(url.as_str(), None))
         } else {
-            Ok(PostgisDatasource::new(ds_cfg.dbconn.as_ref().unwrap()))
+            Ok(PostgisDatasource::new(
+                ds_cfg.dbconn.as_ref().unwrap(),
+                ds_cfg.pool,
+            ))
         }
     }
 

t-rex-core/src/datasource/postgis_test.rs

@@ -61,7 +61,7 @@ fn test_from_geom_fields() {
 #[ignore]
 fn test_detect_layers() {
     let pg: PostgisDatasource = match env::var("DBCONN") {
-        Result::Ok(val) => Some(PostgisDatasource::new(&val).connected()),
+        Result::Ok(val) => Some(PostgisDatasource::new(&val, Some(1)).connected()),
         Result::Err(_) => panic!("DBCONN undefined"),
     }
     .unwrap();
@@ -75,7 +75,7 @@ fn test_detect_layers() {
 #[ignore]
 fn test_detect_columns() {
     let pg: PostgisDatasource = match env::var("DBCONN") {
-        Result::Ok(val) => Some(PostgisDatasource::new(&val).connected()),
+        Result::Ok(val) => Some(PostgisDatasource::new(&val, Some(1)).connected()),
         Result::Err(_) => panic!("DBCONN undefined"),
     }
     .unwrap();
@@ -99,7 +99,7 @@ fn test_detect_columns() {
 #[ignore]
 fn test_extent_query() {
     let pg: PostgisDatasource = match env::var("DBCONN") {
-        Result::Ok(val) => Some(PostgisDatasource::new(&val).connected()),
+        Result::Ok(val) => Some(PostgisDatasource::new(&val, Some(1)).connected()),
         Result::Err(_) => panic!("DBCONN undefined"),
     }
     .unwrap();
@@ -121,7 +121,7 @@ fn test_extent_query() {
 
 #[test]
 fn test_feature_query() {
-    let pg = PostgisDatasource::new("postgresql://pi@localhost/osm2vectortiles");
+    let pg = PostgisDatasource::new("postgresql://pi@localhost/osm2vectortiles", Some(1));
     let mut layer = Layer::new("points");
     layer.table_name = Some(String::from("osm_place_point"));
     layer.geometry_field = Some(String::from("geometry"));
@@ -236,7 +236,7 @@ fn test_feature_query() {
 
 #[test]
 fn test_query_params() {
-    let pg = PostgisDatasource::new("postgresql://pi@localhost/osm2vectortiles");
+    let pg = PostgisDatasource::new("postgresql://pi@localhost/osm2vectortiles", Some(1));
     let mut layer = Layer::new("buildings");
     layer.geometry_field = Some(String::from("way"));
 
@@ -281,7 +281,7 @@ fn test_query_params() {
 #[ignore]
 fn test_retrieve_features() {
     let mut pg: PostgisDatasource = match env::var("DBCONN") {
-        Result::Ok(val) => Some(PostgisDatasource::new(&val).connected()),
+        Result::Ok(val) => Some(PostgisDatasource::new(&val, Some(1)).connected()),
         Result::Err(_) => panic!("DBCONN undefined"),
     }
     .unwrap();
@@ -340,7 +340,7 @@ fn test_retrieve_features() {
 #[should_panic(expected = "geometry_field undefined")]
 fn test_no_geom_field() {
     let mut pg: PostgisDatasource = match env::var("DBCONN") {
-        Result::Ok(val) => Some(PostgisDatasource::new(&val).connected()),
+        Result::Ok(val) => Some(PostgisDatasource::new(&val, Some(1)).connected()),
         Result::Err(_) => panic!("DBCONN undefined"),
     }
     .unwrap();

t-rex-service/src/datasources.rs

@@ -157,7 +157,7 @@ impl Datasources {
         if let Some(dbconn) = args.value_of("dbconn") {
             datasources.add(
                 &"dbconn".to_string(),
-                Datasource::Postgis(PostgisDatasource::new(dbconn)),
+                Datasource::Postgis(PostgisDatasource::new(dbconn, None)),
             );
         }
         if let Some(datasource) = args.value_of("datasource") {

t-rex-service/src/mvt_service_test.rs

@@ -17,7 +17,7 @@ fn mvt_service() -> MvtService {
     use std::env;
 
     let pg: PostgisDatasource = match env::var("DBCONN") {
-        Result::Ok(val) => Some(PostgisDatasource::new(&val).connected()),
+        Result::Ok(val) => Some(PostgisDatasource::new(&val, Some(1)).connected()),
         Result::Err(_) => panic!("DBCONN undefined"),
     }
     .unwrap();

t-rex-service/src/qgs_reader.rs

@@ -203,7 +203,7 @@ pub fn read_qgs(fname: &str) -> (Datasources, Tileset) {
                 layer.geometry_field = Some(info.geometry_field);
                 layer.geometry_type = Some(info.geometry_type);
                 layer.srid = Some(info.srid);
-                Datasource::Postgis(PostgisDatasource::new(&info.dbconn))
+                Datasource::Postgis(PostgisDatasource::new(&info.dbconn, None))
             }
             _ => continue,
         };