Add a nix flake that sets up a development environment (via devenv) (#15495)

1 files changed, 204 insertions, 0 deletions

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+# A nix flake that sets up a complete Synapse development environment. Dependencies
+# for the SyTest (https://github.com/matrix-org/sytest) and Complement
+# (https://github.com/matrix-org/complement) Matrix homeserver test suites are also
+# installed automatically.
+#
+# You must have already installed nix (https://nixos.org) on your system to use this.
+# nix can be installed on Linux or MacOS; NixOS is not required. Windows is not
+# directly supported, but nix can be installed inside of WSL2 or even Docker
+# containers. Please refer to https://nixos.org/download for details.
+#
+# You must also enable support for flakes in Nix. See the following for how to
+# do so permanently: https://nixos.wiki/wiki/Flakes#Enable_flakes
+#
+# Usage:
+#
+# With nix installed, navigate to the directory containing this flake and run
+# `nix develop --impure`. The `--impure` is necessary in order to store state
+# locally from "services", such as PostgreSQL and Redis.
+#
+# You should now be dropped into a new shell with all programs and dependencies
+# availabile to you!
+#
+# You can start up pre-configured, local PostgreSQL and Redis instances by
+# running: `devenv up`. To stop them, use Ctrl-C.
+#
+# A PostgreSQL database called 'synapse' will be set up for you, along with
+# a PostgreSQL user named 'synapse_user'.
+# The 'host' can be found by running `echo $PGHOST` with the development
+# shell activated. Use these values to configure your Synapse to connect
+# to the local PostgreSQL database. You do not need to specify a password.
+# https://matrix-org.github.io/synapse/latest/postgres
+#
+# All state (the venv, postgres and redis data and config) are stored in
+# .devenv/state. Deleting a file from here and then re-entering the shell
+# will recreate these files from scratch.
+#
+# You can exit the development shell by typing `exit`, or using Ctrl-D.
+#
+# If you would like this development environment to activate automatically
+# upon entering this directory in your terminal, first install `direnv`
+# (https://direnv.net/). Then run `echo 'use flake . --impure' >> .envrc` at
+# the root of the Synapse repo. Finally, run `direnv allow .` to allow the
+# contents of '.envrc' to run every time you enter this directory. Voilà!
+
+{
+  inputs = {
+    # Use the master/unstable branch of nixpkgs. The latest stable, 22.11,
+    # does not contain 'perl536Packages.NetAsyncHTTP', needed by Sytest.
+    nixpkgs.url = "github:NixOS/nixpkgs/master";
+    # Output a development shell for x86_64/aarch64 Linux/Darwin (MacOS).
+    systems.url = "github:nix-systems/default";
+    # A development environment manager built on Nix. See https://devenv.sh.
+    # This is temporarily overridden to a fork that fixes a quirk between
+    # devenv's service and python language features. This can be removed
+    # when https://github.com/cachix/devenv/pull/559 is merged upstream.
+    devenv.url = "github:anoadragon453/devenv/anoa/fix_languages_python";
+    #devenv.url = "github:cachix/devenv/main";
+    # Rust toolchains and rust-analyzer nightly.
+    fenix = {
+      url = "github:nix-community/fenix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+  };
+
+  outputs = { self, nixpkgs, devenv, systems, ... } @ inputs:
+    let
+      forEachSystem = nixpkgs.lib.genAttrs (import systems);
+    in {
+      devShells = forEachSystem (system:
+        let
+          pkgs = nixpkgs.legacyPackages.${system};
+        in {
+          # Everything is configured via devenv - a nix module for creating declarative
+          # developer environments. See https://devenv.sh/reference/options/ for a list
+          # of all possible options.
+          default = devenv.lib.mkShell {
+            inherit inputs pkgs;
+            modules = [
+              {
+                # Make use of the Starship command prompt when this development environment
+                # is manually activated (via `nix develop --impure`).
+                # See https://starship.rs/ for details on the prompt itself.
+                starship.enable = true;
+
+                # Configure packages to install.
+                # Search for package names at https://search.nixos.org/packages?channel=unstable
+                packages = with pkgs; [
+                  # Native dependencies for running Synapse.
+                  icu
+                  libffi
+                  libjpeg
+                  libpqxx
+                  libwebp
+                  libxml2
+                  libxslt
+                  sqlite
+
+                  # Native dependencies for unit tests (SyTest also requires OpenSSL).
+                  openssl
+
+                  # Native dependencies for running Complement.
+                  olm
+                ];
+
+                # Install Python and manage a virtualenv with Poetry.
+                languages.python.enable = true;
+                languages.python.poetry.enable = true;
+                # Automatically activate the poetry virtualenv upon entering the shell.
+                languages.python.poetry.activate.enable = true;
+                # Install all extra Python dependencies; this is needed to run the unit
+                # tests and utilitise all Synapse features.
+                languages.python.poetry.install.arguments = ["--extras all"];
+                # Install the 'matrix-synapse' package from the local checkout.
+                languages.python.poetry.install.installRootPackage = true;
+
+                # This is a work-around for NixOS systems. NixOS is special in
+                # that you can have multiple versions of packages installed at
+                # once, including your libc linker!
+                #
+                # Some binaries built for Linux expect those to be in a certain
+                # filepath, but that is not the case on NixOS. In that case, we
+                # force compiling those binaries locally instead.
+                env.POETRY_INSTALLER_NO_BINARY = "ruff";
+
+                # Install dependencies for the additional programming languages
+                # involved with Synapse development.
+                #
+                # * Rust is used for developing and running Synapse.
+                # * Golang is needed to run the Complement test suite.
+                # * Perl is needed to run the SyTest test suite.
+                languages.go.enable = true;
+                languages.rust.enable = true;
+                languages.rust.version = "stable";
+                languages.perl.enable = true;
+
+                # Postgres is needed to run Synapse with postgres support and
+                # to run certain unit tests that require postgres.
+                services.postgres.enable = true;
+
+                # On the first invocation of `devenv up`, create a database for
+                # Synapse to store data in.
+                services.postgres.initdbArgs = ["--locale=C" "--encoding=UTF8"];
+                services.postgres.initialDatabases = [
+                  { name = "synapse"; }
+                ];
+                # Create a postgres user called 'synapse_user' which has ownership
+                # over the 'synapse' database.
+                services.postgres.initialScript = ''
+                CREATE USER synapse_user;
+                ALTER DATABASE synapse OWNER TO synapse_user;
+                '';
+
+                # Redis is needed in order to run Synapse in worker mode.
+                services.redis.enable = true;
+
+                # Define the perl modules we require to run SyTest.
+                #
+                # This list was compiled by cross-referencing https://metacpan.org/
+                # with the modules defined in './cpanfile' and then finding the
+                # corresponding nix packages on https://search.nixos.org/packages.
+                #
+                # This was done until `./install-deps.pl --dryrun` produced no output.
+                env.PERL5LIB = "${with pkgs.perl536Packages; makePerlPath [
+                  DBI
+                  ClassMethodModifiers
+                  CryptEd25519
+                  DataDump
+                  DBDPg
+                  DigestHMAC
+                  DigestSHA1
+                  EmailAddressXS
+                  EmailMIME
+                  EmailSimple  # required by Email::Mime
+                  EmailMessageID  # required by Email::Mime
+                  EmailMIMEContentType  # required by Email::Mime
+                  TextUnidecode  # required by Email::Mime
+                  ModuleRuntime  # required by Email::Mime
+                  EmailMIMEEncodings  # required by Email::Mime
+                  FilePath
+                  FileSlurper
+                  Future
+                  GetoptLong
+                  HTTPMessage
+                  IOAsync
+                  IOAsyncSSL
+                  IOSocketSSL
+                  NetSSLeay
+                  JSON
+                  ListUtilsBy
+                  ScalarListUtils
+                  ModulePluggable
+                  NetAsyncHTTP
+                  MetricsAny  # required by Net::Async::HTTP
+                  NetAsyncHTTPServer
+                  StructDumb
+                  URI
+                  YAMLLibYAML
+                ]}";
+              }
+            ];
+          };
+        });
+    };
+}