diff -r 3dfbd0b91950 -r 4cfaa02055cd src/server/plugins/postgresql/resource.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/server/plugins/postgresql/resource.c	Sat Jan 22 19:13:40 2022 +0100
@@ -0,0 +1,130 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 2022 Olaf Wintermann. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "resource.h"
+
+static ResourceType pg_resource_type = {
+    (resource_pool_init_func)pg_resourcepool_init,
+    (resource_pool_destroy_func)pg_resourcepool_destroy,
+    (resource_pool_createresource_func)pg_resourcepool_createresource,
+    (resource_pool_freeresource_func)pg_resourcepool_freeresource,
+    (resource_pool_prepare_func)pg_resourcepool_prepare,
+    (resource_pool_finish_func)pg_resourcepool_finish,
+    (resource_pool_getresourcedata_func)pg_resourcepool_getresourcedata
+};
+
+ResourceType* pg_get_resource_type(void) {
+    return &pg_resource_type;
+}
+
+void * pg_resourcepool_init(pool_handle_t *pool, const char *rpname, pblock *pb) {
+    char *connection = pblock_findval("Connection", pb);
+    if(!connection) {
+        log_ereport(LOG_MISCONFIG, "Resource pool %s: Missing Connection parameter", rpname);
+        return NULL;
+    }
+    
+    // test connection
+    PGconn *test_connection = PQconnectdb(connection);
+    if(pg_check_connection(rpname, test_connection)) {
+        return NULL; // error, pg_check_connection does the logging
+    }
+    PQfinish(test_connection);
+    
+    PgResourcePool *pg = pool_malloc(pool, sizeof(PgResourcePool));
+    if(!pg) {
+        return NULL;
+    }
+    pg->pool = pool;
+    pg->name = rpname;
+    pg->connection = connection;
+    
+    return pg;
+    
+}
+
+int pg_check_connection(const char *rpname, PGconn *connection) {
+    if(!connection) {
+        log_ereport(LOG_FAILURE, "Resource pool %s: Cannot create PQ connection", rpname);
+        return 1;
+    }
+    if(PQstatus(connection) != CONNECTION_OK) {
+        char *err = PQerrorMessage(connection);
+        int errlen = 0;
+        if(err) {
+            errlen = strlen(err);
+            if(errlen > 0 && err[errlen-1] == '\n') {
+                errlen--;
+            }
+        }
+        log_ereport(LOG_FAILURE, "Resource pool %s: Failed to connect to database: %.*s", rpname, errlen, err);
+        PQfinish(connection);
+        return 1;
+    }
+    return 0;
+}
+
+
+void   pg_resourcepool_destroy(PgResourcePool *pg) {
+    // unused
+}
+    
+void * pg_resourcepool_createresource(PgResourcePool *pg) {
+    PGconn *connection = PQconnectdb(pg->connection);
+    if(pg_check_connection(pg->name, connection)) {
+        return NULL;
+    }
+    
+    PgResource *res = pool_malloc(pg->pool, sizeof(PgResource));
+    if(!res) {
+        PQfinish(connection);
+        log_ereport(LOG_CATASTROPHE, "pg_resourcepool_createresource: OOM");
+        return NULL;
+    }
+    res->connection = connection;
+    
+    return res;
+}
+
+void   pg_resourcepool_freeresource(PgResourcePool *pg, PgResource *res) {
+    if(res->connection) {
+        PQfinish(res->connection);
+    }
+}
+
+int    pg_resourcepool_prepare(PgResourcePool *pg, PgResource *res) {
+    return 0;
+}
+
+int    pg_resourcepool_finish(PgResourcePool *pg, PgResource *res) {
+    return 0;
+}
+
+void * pg_resourcepool_getresourcedata(PgResource *res) {
+    return res->connection;
+}