Using nix flakes for developer shell (#14888)

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -35,6 +35,7 @@ packages/
 nbproject/
 nbactions.xml
 nb-configuration.xml
+.direnv/
 
 .settings
 

README.md

@@ -263,6 +263,20 @@ If you don't have maven installed, you may directly use the included [maven wrap
 ./mvnw clean install
 ```
 
+#### Nix users
+
+If you're a nix user, you can enter OpenAPI Generator shell, by typing:
+```sh
+nix develop
+```
+It will enter a shell with Java 8 and Maven installed. 
+
+Direnv supports automatically loading of the nix developer shell, so if you're using direnv too, type:
+```sh
+direnv allow
+```
+and have `java` and `mvn` set up with correct versions each time you enter project directory.
+
 The default build contains minimal static analysis (via CheckStyle). To run your build with PMD and Spotbugs, use the `static-analysis` profile:
 
 ```sh

flake.lock

@@ -0,0 +1,42 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1676283394,
+        "narHash": "sha256-XX2f9c3iySLCw54rJ/CZs+ZK6IQy7GXNY4nSOyu2QG4=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "3db36a8b464d0c4532ba1c7dda728f4576d6d073",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1678083093,
+        "narHash": "sha256-eTkS9GcdSAYA3cE9zCAAs9wY3+oM2zT45ydIkAcEFFQ=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "684306b246d05168e42425a3610df7e2c4d51fcd",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,23 @@
+{
+  description = "OpenAPI generator nix flake";
+
+  inputs.nixpkgs.url = "github:nixos/nixpkgs";  
+  inputs.flake-utils.url = "github:numtide/flake-utils";
+
+  outputs = { self, nixpkgs, flake-utils, ... }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+      in
+      {
+        devShells.default = pkgs.mkShell
+          {
+            buildInputs = with pkgs;[
+              jdk8
+              maven
+            ];
+          };
+      }
+    );
+}
+