Convert to flake

This also changes how reveal.js is vendored and as a consequence of this
change, it needs to dereference the build result before deploying it
with netlify. This is because flakes do not like submodules and netlify
does not like symlinks.

.drone.yml

@@ -3,21 +3,20 @@ name: default
 type: exec
 
 steps:
-  - name: submodules
+  - name: lfs
     commands:
-      - git submodule init
-      - git submodule update --recursive --remote
+      - git lfs install
+      - git lfs pull
 
   - name: build
     commands:
-      - nix-build
+      - nix build -L
 
   - name: push
     environment:
       NETLIFY_AUTH_TOKEN:
         from_secret: netlify_auth_token
     commands:
-      - nix-shell -I nixpkgs=./pkgs.nix --run "netlify deploy --prod -d $(readlink -f result)"
-
-node:
-  nix: 1
+      - cp --no-preserve=mode -rL result netlify-does-not-follow-symlinks
+      - nix develop -c netlify deploy --prod -d netlify-does-not-follow-symlinks
+      - rm -rf netlify-does-not-follow-symlinks

.envrc

@@ -1 +1 @@
-use nix
+use flake

.gitignore

@@ -22,4 +22,7 @@
 # reveal js (generated)
 /revealjs/*/index.html
 
+# dependencies added by shell hook
+/revealjs/_assets/reveal.js
+
 /result

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "revealjs/_assets/reveal.js"]
-	path = revealjs/_assets/reveal.js
-	url = https://github.com/hakimel/reveal.js

default.nix

@@ -1,54 +0,0 @@
-let
-  sources = import ./nix/sources.nix;
-  pkgs = import sources.nixpkgs {};
-
-  inherit (import sources.gitignore { inherit (pkgs) lib; }) gitignoreSource;
-
-  python = (pkgs.python38.withPackages (ps: with ps; [
-    CommonMark
-    jinja2
-    pyyaml
-  ]));
-
-  texlive = pkgs.texlive.combine {
-    inherit (pkgs.texlive) scheme-medium
-      appendixnumberbeamer
-      beamertheme-focus
-      beamertheme-metropolis
-      biber
-      biblatex
-      csquotes
-      datetime
-      datetime2
-      datetime2-german
-      enumitem
-      fmtcount
-      multirow
-      pgfopts;
-  };
-in
-pkgs.stdenv.mkDerivation {
-  name = "presis";
-
-  nativeBuildInputs = [
-    python
-    texlive
-  ];
-
-  src = gitignoreSource ./.;
-
-  FONTCONFIG_FILE = pkgs.makeFontsConf {
-    fontDirectories = with pkgs; [
-      fira
-      iosevka
-    ];
-  };
-
-  enableParallelBuilding = true;
-
-  dontFixup = true;
-
-  installPhase = ''
-    cp -r . $out;
-  '';
-}

flake.lock

@@ -0,0 +1,61 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1620759905,
+        "narHash": "sha256-WiyWawrgmyN0EdmiHyG2V+fqReiVi8bM9cRdMaKQOFg=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "b543720b25df6ffdfcf9227afafc5b8c1fabfae8",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1620842550,
+        "narHash": "sha256-hpJOMy5HOKIOxJ5aJoFuXqYjEbkYrFY7pDlXYWowxLg=",
+        "owner": "sbruder",
+        "repo": "nixpkgs",
+        "rev": "3a4a2227bb38ec1f3c773829f5d724248af9632c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "sbruder",
+        "ref": "fix-netlify-cli",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "revealjs": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1602496264,
+        "narHash": "sha256-oN77CUmmvrzObhQbORXAujjb+4IkiYbKVLsi7hddsIM=",
+        "owner": "hakimel",
+        "repo": "reveal.js",
+        "rev": "0582f57517c97a4c7bfeb58762138c78883f94c5",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hakimel",
+        "ref": "4.1.0",
+        "repo": "reveal.js",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs",
+        "revealjs": "revealjs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,84 @@
+{
+  inputs = {
+    #nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
+    # At the time of writing, netlify-cli’s build is failing on unstable.
+    nixpkgs.url = "github:sbruder/nixpkgs/fix-netlify-cli";
+    flake-utils.url = "github:numtide/flake-utils";
+
+    revealjs.url = "github:hakimel/reveal.js/4.1.0";
+    revealjs.flake = false;
+  };
+
+  outputs = { self, flake-utils, nixpkgs, revealjs }: flake-utils.lib.eachDefaultSystem (system:
+    let
+      pkgs = nixpkgs.legacyPackages.${system};
+    in
+    rec {
+      packages.sbruder.presis =
+        let
+          python = (pkgs.python38.withPackages (ps: with ps; [
+            CommonMark
+            jinja2
+            pyyaml
+          ]));
+
+          texlive = pkgs.texlive.combine {
+            inherit (pkgs.texlive)
+              scheme-medium
+              appendixnumberbeamer
+              beamertheme-focus
+              beamertheme-metropolis
+              biber
+              biblatex
+              csquotes
+              datetime
+              datetime2
+              datetime2-german
+              enumitem
+              fmtcount
+              multirow
+              pgfopts;
+          };
+        in
+        pkgs.stdenv.mkDerivation {
+          name = "sbruder-presis";
+
+          nativeBuildInputs = [
+            python
+            texlive
+          ];
+
+          src = self;
+
+          FONTCONFIG_FILE = pkgs.makeFontsConf {
+            fontDirectories = with pkgs; [
+              fira
+              iosevka
+            ];
+          };
+
+          enableParallelBuilding = true;
+
+          configurePhase = ''
+            ln -sfT ${revealjs} revealjs/_assets/reveal.js
+          '';
+
+          installPhase = ''
+            cp -r . $out;
+          '';
+
+          dontFixup = true;
+        };
+
+      defaultPackage = packages.sbruder.presis;
+
+      devShell = pkgs.mkShell {
+        buildInputs = packages.sbruder.presis.nativeBuildInputs ++ (with pkgs; [
+          bash
+          netlify-cli
+        ]);
+
+        shellHook = packages.sbruder.presis.configurePhase;
+      };
+    });
+}

nix/sources.json

@@ -1,26 +0,0 @@
-{
-    "gitignore": {
-        "branch": "master",
-        "description": "Nix function for filtering local git sources",
-        "homepage": "",
-        "owner": "hercules-ci",
-        "repo": "gitignore",
-        "rev": "c4662e662462e7bf3c2a968483478a665d00e717",
-        "sha256": "1npnx0h6bd0d7ql93ka7azhj40zgjp815fw2r6smg8ch9p7mzdlx",
-        "type": "tarball",
-        "url": "https://github.com/hercules-ci/gitignore/archive/c4662e662462e7bf3c2a968483478a665d00e717.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    },
-    "nixpkgs": {
-        "branch": "release-20.09",
-        "description": "Nix Packages collection",
-        "homepage": "",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "99f8282a65821f148df596ba389606e732eaf99d",
-        "sha256": "1mm4j1vjs875yzv03plng43ivny0qm09hxpn0if8g9vc849rwc2g",
-        "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/99f8282a65821f148df596ba389606e732eaf99d.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    }
-}

nix/sources.nix

@@ -1,148 +0,0 @@
-# This file has been generated by Niv.
-
-let
-
-  #
-  # The fetchers. fetch_<type> fetches specs of type <type>.
-  #
-
-  fetch_file = pkgs: spec:
-    if spec.builtin or true then
-      builtins_fetchurl { inherit (spec) url sha256; }
-    else
-      pkgs.fetchurl { inherit (spec) url sha256; };
-
-  fetch_tarball = pkgs: name: spec:
-    let
-      ok = str: ! builtins.isNull (builtins.match "[a-zA-Z0-9+-._?=]" str);
-      # sanitize the name, though nix will still fail if name starts with period
-      name' = stringAsChars (x: if ! ok x then "-" else x) "${name}-src";
-    in
-      if spec.builtin or true then
-        builtins_fetchTarball { name = name'; inherit (spec) url sha256; }
-      else
-        pkgs.fetchzip { name = name'; inherit (spec) url sha256; };
-
-  fetch_git = spec:
-    builtins.fetchGit { url = spec.repo; inherit (spec) rev ref; };
-
-  fetch_local = spec: spec.path;
-
-  fetch_builtin-tarball = name: throw
-    ''[${name}] The niv type "builtin-tarball" is deprecated. You should instead use `builtin = true`.
-        $ niv modify ${name} -a type=tarball -a builtin=true'';
-
-  fetch_builtin-url = name: throw
-    ''[${name}] The niv type "builtin-url" will soon be deprecated. You should instead use `builtin = true`.
-        $ niv modify ${name} -a type=file -a builtin=true'';
-
-  #
-  # Various helpers
-  #
-
-  # The set of packages used when specs are fetched using non-builtins.
-  mkPkgs = sources:
-    let
-      sourcesNixpkgs =
-        import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) {};
-      hasNixpkgsPath = builtins.any (x: x.prefix == "nixpkgs") builtins.nixPath;
-      hasThisAsNixpkgsPath = <nixpkgs> == ./.;
-    in
-      if builtins.hasAttr "nixpkgs" sources
-      then sourcesNixpkgs
-      else if hasNixpkgsPath && ! hasThisAsNixpkgsPath then
-        import <nixpkgs> {}
-      else
-        abort
-          ''
-            Please specify either <nixpkgs> (through -I or NIX_PATH=nixpkgs=...) or
-            add a package called "nixpkgs" to your sources.json.
-          '';
-
-  # The actual fetching function.
-  fetch = pkgs: name: spec:
-
-    if ! builtins.hasAttr "type" spec then
-      abort "ERROR: niv spec ${name} does not have a 'type' attribute"
-    else if spec.type == "file" then fetch_file pkgs spec
-    else if spec.type == "tarball" then fetch_tarball pkgs name spec
-    else if spec.type == "git" then fetch_git spec
-    else if spec.type == "local" then fetch_local spec
-    else if spec.type == "builtin-tarball" then fetch_builtin-tarball name
-    else if spec.type == "builtin-url" then fetch_builtin-url name
-    else
-      abort "ERROR: niv spec ${name} has unknown type ${builtins.toJSON spec.type}";
-
-  # If the environment variable NIV_OVERRIDE_${name} is set, then use
-  # the path directly as opposed to the fetched source.
-  replace = name: drv:
-    let
-      saneName = stringAsChars (c: if isNull (builtins.match "[a-zA-Z0-9]" c) then "_" else c) name;
-      ersatz = builtins.getEnv "NIV_OVERRIDE_${saneName}";
-    in
-      if ersatz == "" then drv else ersatz;
-
-  # Ports of functions for older nix versions
-
-  # a Nix version of mapAttrs if the built-in doesn't exist
-  mapAttrs = builtins.mapAttrs or (
-    f: set: with builtins;
-    listToAttrs (map (attr: { name = attr; value = f attr set.${attr}; }) (attrNames set))
-  );
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/lists.nix#L295
-  range = first: last: if first > last then [] else builtins.genList (n: first + n) (last - first + 1);
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L257
-  stringToCharacters = s: map (p: builtins.substring p 1 s) (range 0 (builtins.stringLength s - 1));
-
-  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L269
-  stringAsChars = f: s: concatStrings (map f (stringToCharacters s));
-  concatStrings = builtins.concatStringsSep "";
-
-  # fetchTarball version that is compatible between all the versions of Nix
-  builtins_fetchTarball = { url, name, sha256 }@attrs:
-    let
-      inherit (builtins) lessThan nixVersion fetchTarball;
-    in
-      if lessThan nixVersion "1.12" then
-        fetchTarball { inherit name url; }
-      else
-        fetchTarball attrs;
-
-  # fetchurl version that is compatible between all the versions of Nix
-  builtins_fetchurl = { url, sha256 }@attrs:
-    let
-      inherit (builtins) lessThan nixVersion fetchurl;
-    in
-      if lessThan nixVersion "1.12" then
-        fetchurl { inherit url; }
-      else
-        fetchurl attrs;
-
-  # Create the final "sources" from the config
-  mkSources = config:
-    mapAttrs (
-      name: spec:
-        if builtins.hasAttr "outPath" spec
-        then abort
-          "The values in sources.json should not have an 'outPath' attribute"
-        else
-          spec // { outPath = replace name (fetch config.pkgs name spec); }
-    ) config.sources;
-
-  # The "config" used by the fetchers
-  mkConfig =
-    { sourcesFile ? if builtins.pathExists ./sources.json then ./sources.json else null
-    , sources ? if isNull sourcesFile then {} else builtins.fromJSON (builtins.readFile sourcesFile)
-    , pkgs ? mkPkgs sources
-    }: rec {
-      # The sources, i.e. the attribute set of spec name to spec
-      inherit sources;
-
-      # The "pkgs" (evaluated nixpkgs) to use for e.g. non-builtin fetchers
-      inherit pkgs;
-    };
-
-in
-mkSources (mkConfig {}) // { __functor = _: settings: mkSources (mkConfig settings); }

pkgs.nix

@@ -1 +0,0 @@
-import (import ./nix/sources.nix).nixpkgs

revealjs/_assets/reveal.js

@@ -1 +0,0 @@
-Subproject commit 15815efe05ca69c35ce66cfdbf93316e1db66ecb

shell.nix

@@ -1,9 +0,0 @@
-let
-  pkgs = import (import ./nix/sources.nix).nixpkgs {};
-in
-(import ./default.nix).overrideAttrs(o: o // {
-  nativeBuildInputs = o.nativeBuildInputs ++ (with pkgs; [
-    bash
-    netlify-cli
-  ]);
-})