I’ll post this here, It might help someone in the future.
Feedback is greatly appreciated.
I use it with direnv on NixOS, It should work with nix on Linux or macOS.
custom commands: pg-stop, pg-start, …
flake.nix
{
description = "General Elixir Project Flake";
#source: 20221130; https://github.com/toraritte/shell.nixes/blob/f9af46639a9bb5fb22705ebdfd25783866e22c0f/elixir-phoenix-postgres/shell.nix
#source: 20221130; https://github.com/webuhu/elixir_nix_example
inputs = {
nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
# otherNixpkgs.url = "github:cw789/nixpkgs/erlang_update";
flake-utils.url = "github:numtide/flake-utils";
};
# outputs = { self, nixpkgs, otherNixpkgs, flake-utils }:
outputs = { self, nixpkgs, flake-utils }:
flake-utils.lib.eachDefaultSystem (system:
let
# elixir_master_overlay = (self: super: {
# elixir = (super.beam.packagesWith super.erlang).elixir.override {
# src = builtins.fetchGit {
# url = "https://github.com/elixir-lang/elixir";
# ref = "master";
# };
# minimumOTPVersion = "25";
# };
# });
# pkgs = import <nixpkgs> { overlays = [ elixir_master_overlay ]; };
# elixir_1_13_1_overlay = (self: super: {
# elixir_1_13 = super.elixir_1_13.override {
# version = "1.13.1";
# sha256 = "0z0b1w2vvw4vsnb99779c2jgn9bgslg7b1pmd9vlbv02nza9qj5p";
# };
# });
# pkgs = import <nixpkgs> { overlays = [ elixir_1_13_1_overlay ]; };
# pkgs = nixpkgs.legacyPackages.${system};
pkgs = import nixpkgs {
inherit system;
};
# otherPkgs = otherNixpkgs.legacyPackages.${system};
LANG = "C.UTF-8";
# LANG= "en_US.UTF-8";
root = ./.;
# otherPkgs = import otherNixpkgs { system = "x86_64-linux"; };
# myOverlay = self: super: { inherit (otherPkgs.legacyPackages) erlang }
# pkgs = import nixpkgs { system = "x86_64-linux"; overlays = [ myOverlay ]; };
# erlang = pkgs.beam.interpreters.erlangR25;
# erlang = otherPkgs.beam.interpreters.erlangR25;
elixir = pkgs.beam.packages.erlangR25.elixir_1_14;
# elixir = otherPkgs.beam.packages.erlangR25.elixir_1_14;
nodejs = pkgs.nodejs-18_x;
postgresql = pkgs.postgresql_14;
in
{
devShells.default = pkgs.mkShell {
inherit LANG;
# PGPORT = "5433"; # default 5432
# enable IEx shell history
ERL_AFLAGS = "-kernel shell_history enabled";
# # In IEX: `open Enum.map`
# ELIXIR_EDITOR = "code --goto __FILE__:__LINE__";
##########################################################
# Without this, almost everything fails with locale issues when
# using `nix-shell --pure` (at least on NixOS).
# See
# + https://github.com/NixOS/nix/issues/318#issuecomment-52986702
# + http://lists.linuxfromscratch.org/pipermail/lfs-support/2004-June/023900.html
##########################################################
LOCALE_ARCHIVE = if pkgs.stdenv.isLinux then "${pkgs.glibcLocales}/lib/locale/locale-archive" else "";
buildInputs = with pkgs; [
elixir
nodejs
postgresql
git
beamPackages.elixir_ls
# Show erlang version:
# erl -eval '{ok, Version} = file:read_file(filename:join([code:root_dir(), "releases", erlang:system_info(otp_release), "OTP_VERSION"])), io:fwrite(Version), halt().' -noshell
# erlang
pgcli
glibcLocales
gnumake
gcc
# readline
# openssl
# libxml2
# curl
# libiconv
# yarn
## Deploy tools
flyctl # fly.io
# gigalixir
# Used for frontend dependencies, you are free to use yarn2nix as well
nodePackages.node2nix
# Formatting .js file
nodePackages.prettier
nixpkgs-fmt
# codespell --skip="./deps/*,./.git/*,./assets/*,./erl_crash.dump" -w
codespell
# dot -Tpng ecto_erd.dot -o erd.png
graphviz
(pkgs.writeShellScriptBin "pg-stop" ''
pg_ctl -D $PGDATA -U postgres stop
'')
(pkgs.writeShellScriptBin "pg-reset" ''
rm -rf $PGDATA
'')
(pkgs.writeShellScriptBin "pg-setup" ''
####################################################################
# If database is not initialized (i.e., $PGDATA directory does not
# exist), then set it up. Seems superfluous given the cleanup step
# above, but handy when one gets to force reboot the iron.
####################################################################
if ! test -d $PGDATA; then
######################################################
# Init PostgreSQL
######################################################
pg_ctl initdb -D $PGDATA
#### initdb --locale=C --encoding=UTF8 --auth-local=peer --auth-host=scram-sha-256 > /dev/null || exit
# initdb --encoding=UTF8 --no-locale --no-instructions -U postgres
######################################################
# PORT ALREADY IN USE
######################################################
# If another `nix-shell` is running with a PostgreSQL
# instance, the logs will show complaints that the
# default port 5432 is already in use. Edit the line
# below with a different port number, uncomment it,
# and try again.
######################################################
if [[ "$PGPORT" ]]; then
sed -i "s|^#port.*$|port = $PGPORT|" $PGDATA/postgresql.conf
fi
echo "listen_addresses = ${"'"}${"'"}" >> $PGDATA/postgresql.conf
echo "unix_socket_directories = '$PGDATA'" >> $PGDATA/postgresql.conf
echo "CREATE USER postgres WITH PASSWORD 'postgres' CREATEDB SUPERUSER;" | postgres --single -E postgres
fi
'')
(pkgs.writeShellScriptBin "pg-start" ''
## # Postgres Fallback using docker
## docker run -e POSTGRES_USER=postgres -e POSTGRES_PASSWORD=postgres -p 5432:5432 postgres:14
[ ! -d $PGDATA ] && pg-setup
####################################################################
# Start PostgreSQL
# ==================================================================
# Setting all necessary configuration options via `pg_ctl` (which
# is basically a wrapper around `postgres`) instead of editing
# `postgresql.conf` directly with `sed`. See docs:
#
# + https://www.postgresql.org/docs/current/app-pg-ctl.html
# + https://www.postgresql.org/docs/current/app-postgres.html
#
# See more on the caveats at
# https://discourse.nixos.org/t/how-to-configure-postgresql-declaratively-nixos-and-non-nixos/4063/1
# but recapping out of paranoia:
#
# > use `SHOW` commands to check the options because `postgres -C`
# > "_returns values from postgresql.conf_" (which is not changed by
# > supplying the configuration options on the command line) and
# > "_it does not reflect parameters supplied when the cluster was
# > started._"
#
# OPTION SUMMARY
# --------------------------------------------------------------------
#
# + `unix_socket_directories`
#
# > PostgreSQL will attempt to create a pidfile in
# > `/run/postgresql` by default, but it will fail as it
# > doesn't exist. By changing the configuration option
# > below, it will get created in $PGDATA.
#
# + `listen_addresses`
#
# > In tandem with edits in `pg_hba.conf` (see
# > `HOST_COMMON` below), it configures PostgreSQL to
# > allow remote connections (otherwise only `localhost`
# > will get authenticated and the rest of the traffic
# > discarded).
# >
# > NOTE: the edit to `pga_hba.conf` needs to come
# > **before** `pg_ctl start` (or the service
# > needs to be restarted otherwise), because then
# > the changes are not being reloaded.
# >
# > More info on setting up and troubleshooting remote
# > PosgreSQL connections (these are all mirrors of the
# > same text; again, paranoia):
# >
# > + https://stackoverflow.com/questions/24504680/connect-to-postgres-server-on-google-compute-engine
# > + https://stackoverflow.com/questions/47794979/connecting-to-postgres-server-on-google-compute-engine
# > + https://medium.com/scientific-breakthrough-of-the-afternoon/configure-postgresql-to-allow-remote-connections-af5a1a392a38
# > + https://gist.github.com/toraritte/f8c7fe001365c50294adfe8509080201#file-configure-postgres-to-allow-remote-connection-md
HOST_COMMON="host\s\+all\s\+all"
sed -i "s|^$HOST_COMMON.*127.*$|host all all 0.0.0.0/0 trust|" $PGDATA/pg_hba.conf
sed -i "s|^$HOST_COMMON.*::1.*$|host all all ::/0 trust|" $PGDATA/pg_hba.conf
# + `log*`
#
# > Setting up basic logging, to see remote connections
# > for example.
# >
# > See the docs for more:
# > https://www.postgresql.org/docs/current/runtime-config-logging.html
pg_ctl \
-D $PGDATA \
-l $PGDATA/postgres.log \
-o "-c unix_socket_directories='$PGDATA'" \
-o "-c listen_addresses='*'" \
-o "-c log_destination='stderr'" \
-o "-c logging_collector=on" \
-o "-c log_directory='log'" \
-o "-c log_filename='postgresql-%Y-%m-%d_%H%M%S.log'" \
-o "-c log_min_messages=info" \
-o "-c log_min_error_statement=info" \
-o "-c log_connections=on" \
start
'')
(pkgs.writeShellScriptBin "pg-console" ''
psql --host $PGDATA -U postgres
'')
(pkgs.writeShellScriptBin "pg-mix-setup" ''
# ####/################################################################
# # Install Node.js dependencies if not done yet.
# ####################################################################
# if test -d "$PWD/assets/" && ! test -d "$PWD/assets/node_modules/"; then
# (cd assets && npm install)
# fi
####################################################################
# If $MIX_HOME doesn't exist, set it up.
####################################################################
if ! test -d $MIX_HOME; then
######################################################
# ... but first, test whether there is a `_backup`
# directory. Had issues with installing Hex on NixOS,
# and Hex and Phoenix can be copied from there, just
# in case.
######################################################
if test -d "$PWD/_backup"; then
cp -r _backup/.mix .nix-shell/
else
######################################################
# Install Hex and Phoenix via the network
######################################################
yes | ${elixir}/bin/mix local.hex
# Install Phoenix
# yes | ${elixir}/bin/mix archive.install hex phx_new
#TODO:Go to stable whenever it's released
yes | ${elixir}/bin/mix archive.install hex phx_new 1.7.0-rc.0
fi
fi
if test -f "mix.exs"; then
# These are not in the `if` section above, because of
# the `hex` install glitch, it could be that there is
# already a `$MIX_HOME` folder. See 2019-08-05_0553
${elixir}/bin/mix deps.get
######################################################
# `ecto.setup` is defined in `mix.exs` by default when
# Phoenix project is generated via `mix phx.new`.
# It does `ecto.create`, `ecto.migrate`, and run
# `priv/seeds`.
######################################################
${elixir}/bin/mix ecto.setup
fi
'')
(pkgs.writeShellScriptBin "check-formatted" ''
cd ${root}
echo " > CHECKING nix formatting"
${pkgs.nixpkgs-fmt}/bin/nixpkgs-fmt *.nix --check
echo " > CHECKING mix formatting"
${elixir}/bin/mix format --check-formatted
'')
]
++ pkgs.lib.optional pkgs.stdenv.isLinux pkgs.libnotify # For ExUnit Notifier on Linux.
++ pkgs.lib.optional pkgs.stdenv.isLinux pkgs.inotify-tools # For file_system on Linux.
++ pkgs.lib.optional pkgs.stdenv.isDarwin pkgs.terminal-notifier # For ExUnit Notifier on macOS.
++ pkgs.lib.optionals pkgs.stdenv.isDarwin (with pkgs.darwin.apple_sdk.frameworks; [
# For file_system on macOS.
CoreFoundation
CoreServices
]);
shellHook = ''
if ! test -d .nix-shell; then
mkdir .nix-shell
fi
export NIX_SHELL_DIR=$PWD/.nix-shell
# Put the PostgreSQL databases in the project directory.
export PGDATA=$NIX_SHELL_DIR/db
# Put any Mix-related data in the project directory.
export MIX_HOME=$NIX_SHELL_DIR/.mix
export MIX_ARCHIVES=$MIX_HOME/archives
export HEX_HOME=$NIX_SHELL_DIR/.hex
export PATH=$MIX_HOME/bin:$PATH
export PATH=$HEX_HOME/bin:$PATH
export PATH=$MIX_HOME/escripts:$PATH
export LIVEBOOK_HOME=$PWD
${elixir}/bin/mix --version
${elixir}/bin/iex --version
'';
};
}
);
}
