add shard init for shard node

src/exchange-tools/taler-exchange-dbinit.c

@@ -50,9 +50,14 @@ static int gc_db;
 static uint32_t num_partitions;
 
 /**
- * -S option: setup a sharded database
+ * -F option: setup a sharded database, i.e. create foreign tables/server
  */
-static uint32_t num_shards;
+static uint32_t num_foreign_servers;
+
+/**
+ * -S option: setup a database on a shard server, creates tables with suffix shard_idx
+ */
+static uint32_t shard_idx;
 
 /**
  * Main function that will be run.
@@ -89,6 +94,20 @@ run (void *cls,
                   "Could not drop tables as requested. Either database was not yet initialized, or permission denied. Consult the logs. Will still try to create new tables.\n");
     }
   }
+  if (1 <
+      shard_idx)
+  {
+    if (GNUNET_OK != plugin->create_shard_tables (plugin->cls, shard_idx))
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  "Could not create shard database\n");
+      global_ret = EXIT_NOTINSTALLED;
+    }
+    /* We do not want to continue if we are on a shard */
+    TALER_EXCHANGEDB_plugin_unload (plugin);
+    plugin = NULL;
+    return;
+  }
   if (GNUNET_OK !=
       plugin->create_tables (plugin->cls))
   {
@@ -118,9 +137,10 @@ run (void *cls,
     }
   }
   else if (1 <
-           num_shards)
+           num_foreign_servers)
   {
-    if (GNUNET_OK != plugin->setup_shards (plugin->cls, num_shards))
+    if (GNUNET_OK != plugin->setup_foreign_servers (plugin->cls,
+                                                    num_foreign_servers))
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                   "Could not setup shards. Aborting\n");
@@ -200,11 +220,16 @@ main (int argc,
                                "NUMBER",
                                "Setup a partitioned database where each table which can be partitioned holds NUMBER partitions on a single DB node (NOTE: this is different from sharding)",
                                &num_partitions),
+    GNUNET_GETOPT_option_uint ('F',
+                               "foreign",
+                               "NUMBER",
+                               "Setup a sharded database whit N foreign servers (shards) / tables",
+                               &num_foreign_servers),
     GNUNET_GETOPT_option_uint ('S',
                                "shard",
-                               "NUMBER",
+                               "INDEX",
-                               "Setup a sharded database whit N shards",
+                               "Setup a shard server, creates tables with INDEX as suffix",
-                               &num_shards),
+                               &shard_idx),
     GNUNET_GETOPT_OPTION_END
   };
   enum GNUNET_GenericReturnValue ret;

src/exchangedb/common-0001.sql

@@ -1484,6 +1484,7 @@ $$;
 --------------------- Sharding ---------------------------
 
 ---------------------- Shards ----------------------------
+
 CREATE OR REPLACE FUNCTION setup_shard(
   shard_suffix VARCHAR
 )
@@ -1553,6 +1554,7 @@ END
 $$;
 
 ------------------------------ Master ----------------------------------
+
 CREATE OR REPLACE FUNCTION create_foreign_table(
     source_table_name VARCHAR
     ,modulus INTEGER
@@ -1849,18 +1851,21 @@ COMMENT ON FUNCTION create_shard_server
   IS 'Create a shard server on the master
       node with all foreign tables and user mappings';
 
-CREATE OR REPLACE FUNCTION create_shards(
+CREATE OR REPLACE FUNCTION create_foreign_servers(
-  num_shards INTEGER
+  amount INTEGER
   ,domain VARCHAR DEFAULT 'perf.taler'
 )
   RETURNS VOID
   LANGUAGE plpgsql
 AS $$
 BEGIN
-  FOR i IN 1..num_shards LOOP
+
+  PERFORM master_prepare_sharding();
+
+  FOR i IN 1..amount LOOP
     PERFORM create_shard_server(
       i
-     ,num_shards
+     ,amount
      ,i
      ,'shard-' || i::varchar || '.' || domain
      ,'taler'

src/exchangedb/exchange-0001.sql

@@ -1484,6 +1484,7 @@ $$;
 --------------------- Sharding ---------------------------
 
 ---------------------- Shards ----------------------------
+
 CREATE OR REPLACE FUNCTION setup_shard(
   shard_suffix VARCHAR
 )
@@ -1553,6 +1554,7 @@ END
 $$;
 
 ------------------------------ Master ----------------------------------
+
 CREATE OR REPLACE FUNCTION create_foreign_table(
     source_table_name VARCHAR
     ,modulus INTEGER
@@ -1849,18 +1851,21 @@ COMMENT ON FUNCTION create_shard_server
   IS 'Create a shard server on the master
       node with all foreign tables and user mappings';
 
-CREATE OR REPLACE FUNCTION create_shards(
+CREATE OR REPLACE FUNCTION create_foreign_servers(
-  num_shards INTEGER
+  amount INTEGER
   ,domain VARCHAR DEFAULT 'perf.taler'
 )
   RETURNS VOID
   LANGUAGE plpgsql
 AS $$
 BEGIN
-  FOR i IN 1..num_shards LOOP
+
+  PERFORM master_prepare_sharding();
+
+  FOR i IN 1..amount LOOP
     PERFORM create_shard_server(
       i
-     ,num_shards
+     ,amount
      ,i
      ,'shard-' || i::varchar || '.' || domain
      ,'taler'

src/exchangedb/plugin_exchangedb_postgres.c

@@ -198,6 +198,49 @@ postgres_create_tables (void *cls)
 }
 
 
+/**
+ * Create tables of a shard node with index idx
+ *
+ * @param cls the `struct PostgresClosure` with the plugin-specific state
+ * @param idx the shards index, will be appended as suffix to all tables
+ * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
+ */
+static enum GNUNET_GenericReturnValue
+postgres_create_shard_tables (void *cls,
+                              uint32_t idx)
+{
+  struct PostgresClosure *pg = cls;
+  struct GNUNET_PQ_Context *conn;
+  enum GNUNET_GenericReturnValue ret;
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_uint32 (&idx),
+    GNUNET_PQ_query_param_end
+  };
+  struct GNUNET_PQ_PreparedStatement ps[] = {
+    GNUNET_PQ_make_prepare ("create_shard_tables",
+                            "SELECT"
+                            " setup_shard"
+                            " ($1);",
+                            1),
+    GNUNET_PQ_PREPARED_STATEMENT_END
+  };
+
+  conn = GNUNET_PQ_connect_with_cfg (pg->cfg,
+                                     "exchangedb-postgres",
+                                     "shard-",
+                                     NULL,
+                                     ps);
+  if (NULL == conn)
+    return GNUNET_SYSERR;
+  if (0 > GNUNET_PQ_eval_prepared_non_select (conn,
+                                              "create_shard_tables",
+                                              params))
+    ret = GNUNET_SYSERR;
+  GNUNET_PQ_disconnect (conn);
+  return ret;
+}
+
+
 /**
  * Setup partitions of already existing tables
  *
@@ -207,7 +250,7 @@ postgres_create_tables (void *cls)
  */
 static enum GNUNET_GenericReturnValue
 postgres_setup_partitions (void *cls,
-                           const uint32_t num)
+                           uint32_t num)
 {
   struct PostgresClosure *pg = cls;
   struct GNUNET_PQ_Context *conn;
@@ -227,7 +270,7 @@ postgres_setup_partitions (void *cls,
 
   conn = GNUNET_PQ_connect_with_cfg (pg->cfg,
                                      "exchangedb-postgres",
-                                     "exchage-",
+                                     NULL,
                                      NULL,
                                      ps);
   if (NULL == conn)
@@ -243,15 +286,15 @@ postgres_setup_partitions (void *cls,
 
 
 /**
- * Setup shards for already existing tables
+ * Setup foreign servers (shards) for already existing tables
  *
  * @param cls the `struct PostgresClosure` with the plugin-specific state
- * @param num the number of shard servers to create for each partitioned table
+ * @param num the number of foreign servers (shards) to create for each partitioned table
  * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
  */
 static enum GNUNET_GenericReturnValue
-postgres_setup_shards (void *cls,
+postgres_setup_foreign_servers (void *cls,
-                       const uint32_t num)
+                                uint32_t num)
 {
   struct PostgresClosure *pg = cls;
   struct GNUNET_PQ_Context *conn;
@@ -261,14 +304,9 @@ postgres_setup_shards (void *cls,
     GNUNET_PQ_query_param_end
   };
   struct GNUNET_PQ_PreparedStatement ps[] = {
-    GNUNET_PQ_make_prepare ("setup_shards",
+    GNUNET_PQ_make_prepare ("create_foreign_servers",
                             "SELECT"
-                            " master_prepare_sharding"
+                            " create_foreign_servers"
-                            " ();",
-                            0),
-    GNUNET_PQ_make_prepare ("create_shards",
-                            "SELECT"
-                            " create_shards"
                             " ($1);",
                             1),
     GNUNET_PQ_PREPARED_STATEMENT_END
@@ -276,18 +314,13 @@ postgres_setup_shards (void *cls,
 
   conn = GNUNET_PQ_connect_with_cfg (pg->cfg,
                                      "exchangedb-postgres",
-                                     "exchage-",
+                                     NULL,
                                      NULL,
                                      ps);
   if (NULL == conn)
     return GNUNET_SYSERR;
-  ret = GNUNET_OK;
   if (0 > GNUNET_PQ_eval_prepared_non_select (conn,
-                                              "setup_shards",
+                                              "create_foreign_servers",
-                                              NULL))
-    ret = GNUNET_SYSERR;
-  if (0 > GNUNET_PQ_eval_prepared_non_select (conn,
-                                              "create_shards",
                                               params))
     ret = GNUNET_SYSERR;
   GNUNET_PQ_disconnect (conn);
@@ -13114,8 +13147,9 @@ libtaler_plugin_exchangedb_postgres_init (void *cls)
   plugin->cls = pg;
   plugin->drop_tables = &postgres_drop_tables;
   plugin->create_tables = &postgres_create_tables;
+  plugin->create_shard_tables = &postgres_create_shard_tables;
   plugin->setup_partitions = &postgres_setup_partitions;
-  plugin->setup_shards = &postgres_setup_shards;
+  plugin->setup_foreign_servers = &postgres_setup_foreign_servers;
   plugin->start = &postgres_start;
   plugin->start_read_committed = &postgres_start_read_committed;
   plugin->commit = &postgres_commit;

src/exchangedb/shard-0001.sql

@@ -1484,6 +1484,7 @@ $$;
 --------------------- Sharding ---------------------------
 
 ---------------------- Shards ----------------------------
+
 CREATE OR REPLACE FUNCTION setup_shard(
   shard_suffix VARCHAR
 )
@@ -1553,6 +1554,7 @@ END
 $$;
 
 ------------------------------ Master ----------------------------------
+
 CREATE OR REPLACE FUNCTION create_foreign_table(
     source_table_name VARCHAR
     ,modulus INTEGER
@@ -1849,18 +1851,21 @@ COMMENT ON FUNCTION create_shard_server
   IS 'Create a shard server on the master
       node with all foreign tables and user mappings';
 
-CREATE OR REPLACE FUNCTION create_shards(
+CREATE OR REPLACE FUNCTION create_foreign_servers(
-  num_shards INTEGER
+  amount INTEGER
   ,domain VARCHAR DEFAULT 'perf.taler'
 )
   RETURNS VOID
   LANGUAGE plpgsql
 AS $$
 BEGIN
-  FOR i IN 1..num_shards LOOP
+
+  PERFORM master_prepare_sharding();
+
+  FOR i IN 1..amount LOOP
     PERFORM create_shard_server(
       i
-     ,num_shards
+     ,amount
      ,i
      ,'shard-' || i::varchar || '.' || domain
      ,'taler'

src/include/taler_exchangedb_plugin.h

@@ -2229,6 +2229,17 @@ struct TALER_EXCHANGEDB_Plugin
   enum GNUNET_GenericReturnValue
   (*create_tables)(void *cls);
 
+  /**
+   * Initialize the database of a shard node
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param idx the current shard index, will be appended to tables as suffix
+   * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
+   */
+  enum GNUNET_GenericReturnValue
+  (*create_shard_tables)(void *cls,
+                         uint32_t idx);
+
   /**
    * Change already present tables of the database to num partitions
    * Only has an effect if there are default partitions only
@@ -2239,10 +2250,11 @@ struct TALER_EXCHANGEDB_Plugin
    */
   enum GNUNET_GenericReturnValue
   (*setup_partitions)(void *cls,
-                      const uint32_t num);
+                      uint32_t num);
 
   /**
-   * Change already present tables of the database to num shards
+   * Change already present tables of the database to num foreign tables on
+   * num foreign servers (shards).
    * Only has an effect if there are default partitions only
    *
    * @param cls the @e cls of this struct with the plugin-specific state
@@ -2253,8 +2265,8 @@ struct TALER_EXCHANGEDB_Plugin
    * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
    */
   enum GNUNET_GenericReturnValue
-  (*setup_shards)(void *cls,
+  (*setup_foreign_servers)(void *cls,
-                  const uint32_t num);
+                           uint32_t num);
 
   /**
    * Start a transaction.