fix: start-server conflicting with running pg (#21)

When having a running postgresql, the following error is produced:

```
$ nix run .#start-server 15
...
2023-08-19 15:25:26.476 -05 [1021103] LOG:  starting PostgreSQL 15.3 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 12.3.0, 64-bit
2023-08-19 15:25:26.476 -05 [1021103] LOG:  could not bind IPv6 address "::1": Address already in use
2023-08-19 15:25:26.476 -05 [1021103] HINT:  Is another postmaster already running on port 5432? If not, wait a few seconds and retry.
2023-08-19 15:25:26.476 -05 [1021103] LOG:  could not bind IPv4 address "127.0.0.1": Address already in use
2023-08-19 15:25:26.476 -05 [1021103] HINT:  Is another postmaster already running on port 5432? If not, wait a few seconds and retry.
2023-08-19 15:25:26.476 -05 [1021103] WARNING:  could not create listen socket for "localhost"
2023-08-19 15:25:26.476 -05 [1021103] FATAL:  could not create any TCP/IP sockets
2023-08-19 15:25:26.479 -05 [1021103] LOG:  database system is shut down
```

This is because it runs using the default 5432.

This changes the default port to 5435 to avoid conflicts.

Additionally:

- Parametrizes the pg default port for all configs(docker and local)
- Adds a port parameter to #start-client, e.g. `nix run .#start-client
  15 5433`

Author: steve-chavez

README.md

@@ -99,7 +99,7 @@ need to download this repository; just use `nix run`:
 nix run github:supabase/nix-postgres#start-server 15
 ```
 
-This will start PostgreSQL 15 on port `5432` on localhost with a temporary directory created by `mktemp -d`. Connect to it:
+This will start PostgreSQL 15 on port `5435` on localhost with a temporary directory created by `mktemp -d`. Connect to it:
 
 ```
 austin@GANON:~$ nix run github:supabase/nix-postgres#start-client 14

docker/init.sh docker/init.sh.indocker/init.sh renamed to docker/init.sh.in

@@ -3,4 +3,4 @@
 
 sudo -u postgres /bin/initdb --locale=C -D /data
 sudo -u postgres ln -s /etc/postgresql.conf /data/postgresql.conf
-sudo -u postgres /bin/postgres -p 5432 -D /data
+sudo -u postgres /bin/postgres -p @PGSQL_DEFAULT_PORT@ -D /data

docs/start-client-server.md

@@ -5,9 +5,9 @@ repository:
 nix run .#start-server 14
 ```
 
-Replace the `14` with a `15`, and you'll be using a different version.
+Replace the `14` with a `15`, and you'll be using a different version. Optionally you can specify a second argument for the port.
 
-This always uses port 5432.
+You likely have a running postgres, so to not cause a conflict, this uses port 5435 by default.
 
 Actually, you don't even need the repository. You can do this from arbitrary
 directories, if the left-hand side of the hash character (`.` in this case) is a

flake.nix

@@ -24,6 +24,8 @@
       system.aarch64-linux
     ]; in flake-utils.lib.eachSystem ourSystems (system:
       let
+        pgsqlDefaultPort = "5435";
+
         # The 'pkgs' variable holds all the upstream packages in nixpkgs, which
         # we can use to build our own images; it is the common name to refer to
         # a copy of nixpkgs which contains all its packages.
@@ -177,13 +179,16 @@
           let
             initScript = pkgs.runCommand "docker-init.sh" {} ''
               mkdir -p $out/bin
-              cp ${./docker/init.sh} $out/bin/init.sh
+              substitute ${./docker/init.sh.in} $out/bin/init.sh \
+                --subst-var-by 'PGSQL_DEFAULT_PORT' '${pgsqlDefaultPort}'
+
               chmod +x $out/bin/init.sh
             '';
 
             postgresqlConfig = pkgs.runCommand "postgresql.conf" {} ''
               mkdir -p $out/etc/
               substitute ${./tests/postgresql.conf.in} $out/etc/postgresql.conf \
+                --subst-var-by 'PGSQL_DEFAULT_PORT' '${pgsqlDefaultPort}' \
                 --subst-var-by PGSODIUM_GETKEY_SCRIPT "${./tests/util/pgsodium_getkey.sh}"
             '';
 
@@ -211,7 +216,7 @@
 
             config = {
               Cmd = [ "/bin/init.sh" ];
-              ExposedPorts = { "5432/tcp" = {}; };
+              ExposedPorts = { "${pgsqlDefaultPort}/tcp" = {}; };
               WorkingDir = "/data";
               Volumes = { "/data" = { }; };
             };
@@ -249,6 +254,7 @@
           start-server = pkgs.runCommand "start-postgres-server" {} ''
             mkdir -p $out/bin
             substitute ${./tools/run-server.sh.in} $out/bin/start-postgres-server \
+              --subst-var-by 'PGSQL_DEFAULT_PORT' '${pgsqlDefaultPort}' \
               --subst-var-by 'PSQL14_BINDIR' '${basePackages.psql_14.bin}' \
               --subst-var-by 'PSQL15_BINDIR' '${basePackages.psql_15.bin}'
             chmod +x $out/bin/start-postgres-server
@@ -258,6 +264,7 @@
           start-client = pkgs.runCommand "start-postgres-client" {} ''
             mkdir -p $out/bin
             substitute ${./tools/run-client.sh.in} $out/bin/start-postgres-client \
+              --subst-var-by 'PGSQL_DEFAULT_PORT' '${pgsqlDefaultPort}' \
               --subst-var-by 'PSQL14_BINDIR' '${basePackages.psql_14.bin}' \
               --subst-var-by 'PSQL15_BINDIR' '${basePackages.psql_15.bin}'
             chmod +x $out/bin/start-postgres-client

tests/postgresql.conf.in

@@ -58,7 +58,7 @@
 # - Connection Settings -
 
 listen_addresses = '*'		# what IP address(es) to listen on;
-#port = 5432				# (change requires restart)
+#port = @PGSQL_DEFAULT_PORT@				# (change requires restart)
 max_connections = 100			# (change requires restart)
 #superuser_reserved_connections = 3	# (change requires restart)
 unix_socket_directories = '/tmp'	# comma-separated list of directories

tools/migrate-tool.sh.in

@@ -49,7 +49,7 @@ echo "Old server build: PSQL $1"
 echo "New server build: PSQL $2"
 echo "Upgrade method: $UPGRADE_METHOD"
 
-PORTNO="${2:-5432}"
+PORTNO="${2:-@PGSQL_DEFAULT_PORT@}"
 DATDIR=$(mktemp -d)
 NEWDAT=$(mktemp -d)
 mkdir -p "$DATDIR" "$NEWDAT"
@@ -117,6 +117,6 @@ if [ "$UPGRADE_METHOD" == "pg_dumpall" ]; then
     cat "$SQLDAT" | $NEWVER/bin/psql -h localhost -d postgres
 
     printf "\n\n\n\n"
-    echo "NOTE: Done, check logs. Stopping the server; new database is located at $NEWDAT" 
+    echo "NOTE: Done, check logs. Stopping the server; new database is located at $NEWDAT"
     $NEWVER/bin/pg_ctl stop -D "$NEWDAT"
 fi

tools/run-client.sh.in

@@ -19,4 +19,6 @@ fi
 
 export PATH=$BINDIR/bin:$PATH
 
-exec psql -h localhost postgres
+PORTNO="${2:-@PGSQL_DEFAULT_PORT@}"
+
+exec psql -p "$PORTNO" -h localhost postgres

tools/run-server.sh.in

@@ -19,14 +19,14 @@ fi
 
 export PATH=$BINDIR/bin:$PATH
 
-PORTNO="${2:-5432}"
+PORTNO="${2:-@PGSQL_DEFAULT_PORT@}"
 DATDIR=$(mktemp -d)
 mkdir -p "$DATDIR"
 
 echo "NOTE: using port $PORTNO for server"
 echo "NOTE: using temporary directory $DATDIR for data, which will not be removed"
 echo "NOTE: you are free to re-use this data directory at will"
-echo 
+echo
 
 initdb -D "$DATDIR" --locale=C
 exec postgres -p "$PORTNO" -D "$DATDIR" -k /tmp