package newcomers in nix

flake.nix

@@ -24,24 +24,35 @@
         "x86_64-darwin"
       ];
       perSystem =
-        { config, pkgs, ... }:
         {
+          config,
+          pkgs,
+          self',
+          ...
+        }:
+        {
+          apps.newcomers = {
+            type = "app";
+            program = self'.packages.newcomers;
+          };
           devShells.default = pkgs.mkShell {
             nativeBuildInputs = [ config.treefmt.build.wrapper ];
-            packages = with pkgs; [
-              (python3.withPackages (
-                p: with p; [
-                  beautifulsoup4
-                  httpx
-                  ldap3
-                  numpy
-                  pandas
-                  requests
-                  tabulate
-                  wand
-                ]
-              ))
-            ];
+            packages = [ self'.packages.python ];
+          };
+          packages = {
+            newcomers = pkgs.python3Packages.callPackage ./newcomers { };
+            python = pkgs.python3.withPackages (
+              p: with p; [
+                beautifulsoup4
+                httpx
+                ldap3
+                numpy
+                pandas
+                requests
+                tabulate
+                wand
+              ]
+            );
           };
           treefmt = {
             projectRootFile = "flake.nix";

newcomers/README.md

@@ -2,17 +2,15 @@
 
 ## Get dependencies
 
-- Get Python 3
-- `pip3 install ldap3` (you might need `sudo`, or *better* `--user`, or *best* a virtualenv)
-- `mkdir -p ~/.cache`
+This project is packaged with a nix flake
 
 ## Go !
 
 - `./greet_newcomers.py`
 
-On the first time, it will construct a database of the guys already here.
+On the first time, it will construct a database of the members already here.
 
-After that, on each launch, it will find the new guys, and send them a greeting mail.
+After that, on each launch, it will find the newcomers, and send them a greeting mail.
 The template of this mail is in `template.txt`.
 
 ## Cron job
@@ -20,5 +18,5 @@ The template of this mail is in `template.txt`.
 To run this script everyday at 5 AM:
 
 ```bash
-(crontab -l; echo "0 5 * * * $(which python) $(pwd)/greet_newcomers.py") | crontab -
+(crontab -l; echo "0 5 * * * cd $(pwd); nix run .#newcomers") | crontab -
 ```

newcomers/default.nix

+{
+  lib,
+  ldap3,
+  buildPythonApplication
+}:
+buildPythonApplication {
+  pname = "greet-newcomers";
+  version = "1.0.0";
+  pyproject = false;
+  dependencies = [ ldap3 ];
+
+  src = lib.fileset.toSource {
+    root = ./.;
+    fileset = lib.fileset.unions [
+      ./greet_newcomers.py
+      ./template.txt
+    ];
+  };
+
+  installPhase = ''
+    install -D -m 755 greet_newcomers.py $out/bin/greet-newcomers
+    install -D -m 644 template.txt $out/share/greet-newcomers/template.txt
+  '';
+
+  meta = {
+    description = "Greet gepetto newcomers";
+    homepage = "https://github.com/gepetto/gepetto-utils/tree/master/newcomers";
+    license = lib.licenses.bsd2;
+    maintainers = [lib.maintainers.nim65s ];
+    mainProgram = "greet-newcomers";
+  };
+}

newcomers/greet_newcomers.py

@@ -3,13 +3,14 @@
 import shelve
 from email.mime.text import MIMEText
 from getpass import getuser
-from smtplib import SMTP
+from os import environ
 from pathlib import Path
+from smtplib import SMTP
 
 from ldap3 import Connection
 
 HERE = Path(__file__).resolve().parent
-SHELF = str(HERE / ".cache")
+SHELF = Path(environ.get("XDG_CACHE_HOME", Path.home() / ".cache")) / "greet-newcomers"
 
 
 def get_gepetto():
@@ -53,7 +54,13 @@ def greet(to, sender):
     if "@" not in to:
         to = "%s@laas.fr" % to
 
-    with (HERE / "template.txt").open() as f:
+    template = HERE / "template.txt"
+    if not template.exists():
+        template = HERE.parent / "share" / "greet-newcomers" / "template.txt"
+    if not template.exists():
+        err = f"can't find template.txt around {HERE}"
+        raise RuntimeError(err)
+    with template.open() as f:
         msg = MIMEText(f.read())
 
     msg["Subject"] = "Welcome in Gepetto !"
@@ -86,9 +93,9 @@ if __name__ == "__main__":
     # Retrieve the login of the current user, who must already be a member
     me = whoami(gepetto)
 
-    for guy in gepetto_ldap:
-        if guy not in gepetto:
-            greet(guy, me)
+    for member in gepetto_ldap:
+        if member not in gepetto:
+            greet(member, me)
 
     # Save the new list
     with shelve.open(SHELF) as shelf: