Improve our docker compose file a little. (#724)

* Improve our docker compose file a little.

Use environment variables rather than very long command lines where it makes
sense, making it easier to see that we're doing the same thing in the three
Postgres nodes.

* Add support for env variables for pg_autoctl do demo run.

Makefile

@@ -207,6 +207,9 @@ build-check:
 build-i386:
 	docker build -t i386:latest -f Dockerfile.i386 .
 
+build-demo:
+	docker build -t citusdata/pg_auto_failover:demo .
+
 # expected to be run from within the i386 docker container
 installcheck-i386:
 	pg_autoctl run &

docker-compose.yml

@@ -12,60 +12,41 @@ services:
     image: citusdata/pg_auto_failover:demo
     environment:
       PGDATA: /tmp/pgaf
-      PG_AUTOCTL_DEBUG: 1
-    command: [
-    "pg_autoctl", "create", "postgres",
-    "--ssl-self-signed",
-    "--auth", "trust",
-    "--pg-hba-lan",
-    "--username", "ad",
-    "--dbname", "analytics",
-    "--monitor", "postgresql://autoctl_node@monitor/pg_auto_failover",
-    "--run"]
+      PGUSER: ad
+      PGDATABASE: analytics
+      PG_AUTOCTL_MONITOR: "postgresql://autoctl_node@monitor/pg_auto_failover"
+    command:  pg_autoctl create postgres --ssl-self-signed --auth trust --pg-hba-lan --run
     expose:
       - 5432
   node2:
     image: citusdata/pg_auto_failover:demo
     environment:
       PGDATA: /tmp/pgaf
-      PG_AUTOCTL_DEBUG: 1
-    command: [
-    "pg_autoctl", "create", "postgres",
-    "--ssl-self-signed",
-    "--auth", "trust",
-    "--pg-hba-lan",
-    "--username", "ad",
-    "--dbname", "analytics",
-    "--monitor", "postgresql://autoctl_node@monitor/pg_auto_failover",
-    "--run"]
+      PGUSER: ad
+      PGDATABASE: analytics
+      PG_AUTOCTL_MONITOR: "postgresql://autoctl_node@monitor/pg_auto_failover"
+    command:  pg_autoctl create postgres --ssl-self-signed --auth trust --pg-hba-lan --run
     expose:
       - 5432
   node3:
     image: citusdata/pg_auto_failover:demo
     environment:
       PGDATA: /tmp/pgaf
-      PG_AUTOCTL_DEBUG: 1
-    command: [
-    "pg_autoctl", "create", "postgres",
-    "--ssl-self-signed",
-    "--auth", "trust",
-    "--pg-hba-lan",
-    "--username", "ad",
-    "--dbname", "analytics",
-    "--monitor", "postgresql://autoctl_node@monitor/pg_auto_failover",
-    "--run"]
+      PGUSER: ad
+      PGDATABASE: analytics
+      PG_AUTOCTL_MONITOR: "postgresql://autoctl_node@monitor/pg_auto_failover"
+    command:  pg_autoctl create postgres --ssl-self-signed --auth trust --pg-hba-lan --run
     expose:
       - 5432
   demo-app:
     image: citusdata/pg_auto_failover:demo
     environment:
       PGDATA: /tmp/pgaf
-      PG_AUTOCTL_DEBUG: 1
-    command: [
-    "pg_autoctl", "do", "demo", "run",
-    "--username", "ad",
-    "--clients", "10",
-    "--duration", "125",
-    "--first-failover", "45",
-    "--failover-freq", "30",
-    "--monitor", "postgresql://autoctl_node@monitor/pg_auto_failover"]
+      PGUSER: ad
+      PGDATABASE: analytics
+      PG_AUTOCTL_MONITOR: "postgresql://autoctl_node@monitor/pg_auto_failover"
+      PG_AUTOCTL_DEMO_CLIENTS: 10
+      PG_AUTOCTL_DEMO_DURATION: 125
+      PG_AUTOCTL_DEMO_FAILOVER_FREQ: 30
+      PG_AUTOCTL_DEMO_FAILOVER_FIRST: 45
+    command:  pg_autoctl do demo run

src/bin/pg_autoctl/cli_do_demoapp.c

@@ -143,6 +143,85 @@ cli_do_demoapp_getopts(int argc, char **argv)
 	options.doFailover = true;
 	strlcpy(options.formation, "default", sizeof(options.formation));
 
+	/*
+	 * Add support for environment variables for some of those options.
+	 */
+	if (env_exists(PG_AUTOCTL_DEMO_CLIENTS))
+	{
+		char clients[BUFSIZE] = { 0 };
+
+		if (!get_env_copy(PG_AUTOCTL_DEMO_CLIENTS, clients, sizeof(clients)))
+		{
+			/* errors have already been logged */
+			exit(EXIT_CODE_BAD_ARGS);
+		}
+
+		if (!stringToInt(clients, &(options.clientsCount)))
+		{
+			log_fatal("Failed to parse \"%s\" integer value \"%s\"",
+					  PG_AUTOCTL_DEMO_CLIENTS,
+					  clients);
+			exit(EXIT_CODE_BAD_ARGS);
+		}
+	}
+
+	if (env_exists(PG_AUTOCTL_DEMO_DURATION))
+	{
+		char duration[BUFSIZE] = { 0 };
+
+		if (!get_env_copy(PG_AUTOCTL_DEMO_DURATION, duration, sizeof(duration)))
+		{
+			/* errors have already been logged */
+			exit(EXIT_CODE_BAD_ARGS);
+		}
+
+		if (!stringToInt(duration, &(options.duration)))
+		{
+			log_fatal("Failed to parse \"%s\" integer value \"%s\"",
+					  PG_AUTOCTL_DEMO_DURATION,
+					  duration);
+			exit(EXIT_CODE_BAD_ARGS);
+		}
+	}
+
+	if (env_exists(PG_AUTOCTL_DEMO_FAILOVER_FIRST))
+	{
+		char first[BUFSIZE] = { 0 };
+
+		if (!get_env_copy(PG_AUTOCTL_DEMO_FAILOVER_FIRST, first, sizeof(first)))
+		{
+			/* errors have already been logged */
+			exit(EXIT_CODE_BAD_ARGS);
+		}
+
+		if (!stringToInt(first, &(options.firstFailover)))
+		{
+			log_fatal("Failed to parse \"%s\" integer value \"%s\"",
+					  PG_AUTOCTL_DEMO_FAILOVER_FIRST,
+					  first);
+			exit(EXIT_CODE_BAD_ARGS);
+		}
+	}
+
+	if (env_exists(PG_AUTOCTL_DEMO_FAILOVER_FREQ))
+	{
+		char freq[BUFSIZE] = { 0 };
+
+		if (!get_env_copy(PG_AUTOCTL_DEMO_FAILOVER_FREQ, freq, sizeof(freq)))
+		{
+			/* errors have already been logged */
+			exit(EXIT_CODE_BAD_ARGS);
+		}
+
+		if (!stringToInt(freq, &(options.failoverFreq)))
+		{
+			log_fatal("Failed to parse \"%s\" integer value \"%s\"",
+					  PG_AUTOCTL_DEMO_FAILOVER_FREQ,
+					  freq);
+			exit(EXIT_CODE_BAD_ARGS);
+		}
+	}
+
 	/*
 	 * The only command lines that are using cli_do_demoapp_getopts are
 	 * terminal ones: they don't accept subcommands. In that case our option

src/bin/pg_autoctl/defaults.h

@@ -34,6 +34,12 @@
 #define PG_AUTOCTL_CANDIDATE_PRIORITY "PG_AUTOCTL_CANDIDATE_PRIORITY"
 #define PG_AUTOCTL_REPLICATION_QUORUM "PG_AUTOCTL_REPLICATION_QUORUM"
 
+/* environment variables for `pg_autoctl do demo run` */
+#define PG_AUTOCTL_DEMO_CLIENTS "PG_AUTOCTL_DEMO_CLIENTS"
+#define PG_AUTOCTL_DEMO_DURATION "PG_AUTOCTL_DEMO_DURATION"
+#define PG_AUTOCTL_DEMO_FAILOVER_FREQ "PG_AUTOCTL_DEMO_FAILOVER_FREQ"
+#define PG_AUTOCTL_DEMO_FAILOVER_FIRST "PG_AUTOCTL_DEMO_FAILOVER_FIRST"
+
 /* default values for the pg_autoctl settings */
 #define POSTGRES_PORT 5432
 #define POSTGRES_DEFAULT_LISTEN_ADDRESSES "*"

src/bin/pg_autoctl/keeper_pg_init.c

@@ -1016,12 +1016,12 @@ create_database_and_extension(Keeper *keeper)
 	 */
 	if (!IS_EMPTY_STRING_BUFFER(pgSetup->username))
 	{
+		char pguser[NAMEDATALEN] = { 0 };
+
 		/*
 		 * Remove PGUSER from the environment when we want to create that very
 		 * user at bootstrap.
 		 */
-		char pguser[NAMEDATALEN] = { 0 };
-
 		if (!get_env_copy_with_fallback("PGUSER", pguser, NAMEDATALEN, ""))
 		{
 			/* errors have already been logged */

src/bin/pg_autoctl/pgsetup.c

@@ -199,7 +199,7 @@ pg_setup_init(PostgresSetup *pgSetup,
 	}
 
 	/* check or find dbname */
-	if (options->dbname[0] != '\0')
+	if (!IS_EMPTY_STRING_BUFFER(options->dbname))
 	{
 		strlcpy(pgSetup->dbname, options->dbname, NAMEDATALEN);
 	}