Build mbsync with with OAUTH2 support

configuration.nix

@@ -113,6 +113,7 @@ with pkgs;
     ./overlays/emacs.nix
     ./overlays/nix-direnv.nix
     ./overlays/openconnect-sso.nix
+    ./overlays/cyrus-sasl-oauth2.nix
   ];
 
 }

flake.lock

@@ -20,6 +20,22 @@
         "type": "github"
       }
     },
+    "cyrus-sasl-xoauth2": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1611713742,
+        "narHash": "sha256-IaH8tNUhM0lUOmFiG4G9cGzsuM9mTWfQrzoQ78MIgZ0=",
+        "owner": "robn",
+        "repo": "sasl2-oauth",
+        "rev": "4236b6fb904d836b85b55ba32128b843fd8c2362",
+        "type": "github"
+      },
+      "original": {
+        "owner": "robn",
+        "repo": "sasl2-oauth",
+        "type": "github"
+      }
+    },
     "emacs-overlay": {
       "locked": {
         "lastModified": 1642217228,
@@ -69,6 +85,7 @@
     "root": {
       "inputs": {
         "agenix": "agenix",
+        "cyrus-sasl-xoauth2": "cyrus-sasl-xoauth2",
         "emacs-overlay": "emacs-overlay",
         "nixpkgs": "nixpkgs",
         "openconnect-sso": "openconnect-sso"

flake.nix

@@ -18,6 +18,10 @@
       url = "github:vlaci/openconnect-sso";
       flake = false;
     };
+    cyrus-sasl-xoauth2 = {
+      url = "github:robn/sasl2-oauth";
+      flake = false;
+    };
   };
 
   outputs = { self, nixpkgs, agenix, ... }@inputs:

modules/software.nix

@@ -11,6 +11,8 @@ let
       sed -i -e "s|#!/usr/bin/env node|#! ${pkgs.nodejs}/bin/node|" node_modules/node-gyp-build/bin.js
     '';
   };
+  isync-oauth2 = isync.overrideAttrs
+    (div: rec { buildInputs = [ openssl patched-cyrus-sasl-oauth2 zlib ]; });
 
 in {
   environment.systemPackages = [
@@ -67,7 +69,7 @@ in {
     citrix_workspace
     # Mail stack
     neomutt
-    isync
+    isync-oauth2
     notmuch
     msmtp
     w3m

overlays/cyrus-sasl-oauth2.nix

@@ -0,0 +1,24 @@
+{ config, lib, pkgs, inputs, ... }:
+
+let
+  cyrus-sasl-xoauth2 = with pkgs;
+    stdenv.mkDerivation {
+      name = "cyrus-sasl-xoauth2";
+      src = inputs.cyrus-sasl-xoauth2;
+      nativeBuildInputs =
+        [ autoreconfHook inputs.nixpkgs.legacyPackages."${system}".cyrus_sasl ];
+    };
+
+in {
+  nixpkgs.overlays = [
+    (final: prev: {
+      patched-cyrus-sasl-oauth2 = prev.cyrus_sasl.overrideAttrs (div: rec {
+        postInstall = ''
+          for lib in ${cyrus-sasl-xoauth2}/lib/sasl2/*; do
+            ln -sf $lib $out/lib/sasl2/
+          done
+        '';
+      });
+    })
+  ];
+}