From d3a3aa85835442262ae6a823dd66bce3d8403ed5 Mon Sep 17 00:00:00 2001
From: Daniel Underwood <git@danielunderwood.dev>
Date: Sat, 5 Mar 2022 17:42:04 -0500
Subject: [PATCH] Tooling: Move from nix-shell to flakes

---
 .gitignore |  1 +
 README.md  |  2 +-
 flake.lock | 26 ++++++++++++++++++++
 flake.nix  | 71 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 99 insertions(+), 1 deletion(-)
 create mode 100644 flake.lock
 create mode 100644 flake.nix

diff --git a/.gitignore b/.gitignore
index 8fce603..b515021 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 data/
+result
diff --git a/README.md b/README.md
index bbe67de..b377fab 100644
--- a/README.md
+++ b/README.md
@@ -7,7 +7,7 @@ An ingress for RSS, Atom, JSONFeed, and other news feeds that provides configura
 ### Local Go
 
 ```shell
-$ nix-shell # Or local environment with go + docker-compose
+$ nix develop # Or local environment with go + docker-compose
 $ $EDITOR config.yaml
 $ docker-compose -f docker-compose.dependencies.yml up -d
 $ go run *.go
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..2bb1162
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,26 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1646406548,
+        "narHash": "sha256-xp+3f76ycZXNf9pG65Ef9KfDl1fas2UQu/cBe/pLd+c=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "47cd6702934434dd02bc53a67dbce3e5493e33a2",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "ref": "nixos-21.11",
+        "type": "indirect"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..c671c8c
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,71 @@
+{
+  description = "Simple configurable RSS ingress";
+
+  # Nixpkgs / NixOS version to use.
+  inputs.nixpkgs.url = "nixpkgs/nixos-21.11";
+
+  outputs = { self, nixpkgs }:
+    let
+
+      # Generate a user-friendly version number.
+      version = builtins.substring 0 8 self.lastModifiedDate;
+
+      # System types to support.
+      supportedSystems = [ "x86_64-linux" "x86_64-darwin" "aarch64-linux" "aarch64-darwin" ];
+
+      # Helper function to generate an attrset '{ x86_64-linux = f "x86_64-linux"; ... }'.
+      forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
+
+      # Nixpkgs instantiated for supported system types.
+      nixpkgsFor = forAllSystems (system: import nixpkgs { inherit system; });
+
+    in
+    {
+
+      # Provide some binary packages for selected system types.
+      packages = forAllSystems (system:
+        let
+          pkgs = nixpkgsFor.${system};
+        in
+        {
+          log2http = pkgs.buildGoModule {
+            pname = "feed-ingress";
+            inherit version;
+            # In 'nix develop', we don't need a copy of the source tree
+            # in the Nix store.
+            src = ./.;
+
+            # This hash locks the dependencies of this package. It is
+            # necessary because of how Go requires network access to resolve
+            # VCS.  See https://www.tweag.io/blog/2021-03-04-gomod2nix/ for
+            # details. Normally one can build with a fake sha256 and rely on native Go
+            # mechanisms to tell you what the hash should be or determine what
+            # it should be "out-of-band" with other tooling (eg. gomod2nix).
+            # To begin with it is recommended to set this, but one must
+            # remeber to bump this hash when your dependencies change.
+            # vendorSha256 = pkgs.lib.fakeSha256;
+
+            vendorSha256 = "sha256-cfBzHO7b2fNUWrlls/FcgfmbHjvOGugcQbd+EDiUmg0=";
+          };
+        });
+
+      # The default package for 'nix build'. This makes sense if the
+      # flake provides only one package or there is a clear "main"
+      # package.
+      defaultPackage = forAllSystems (system: self.packages.${system}.log2http);
+
+      devShell = forAllSystems (system:
+        let pkgs = nixpkgsFor.${system};
+        in pkgs.mkShell {
+          buildInputs = with pkgs; [
+            docker-compose
+            go
+            gopls
+            goimports
+            go-tools
+            kcat
+          ];
+        });
+
+    };
+}