fixup! Add Buildkite pipeline for updating hackage.nix and stackage.nix

Use github tokens for authentication to push to github.

Author: rvl

scripts/update-external.nix

@@ -4,23 +4,36 @@
 
 with stdenv.lib;
 
-writeScript "update-${name}-nix.sh" ''
-  #!${stdenv.shell}
+let
+  repo = "github.com/input-output-hk/${name}.nix.git";
+  tokenFile = "/run/keys/buildkite-nix-tools-token";
+  githubUser = "iohk-devops";
+in
+  writeScript "update-${name}-nix.sh" ''
+    #!${stdenv.shell}
 
-  set -euo pipefail
+    set -euo pipefail
 
-  export PATH="${makeBinPath [ coreutils glibc git nix-tools cabal-install nix-prefetch-git ]}"
+    export PATH="${makeBinPath [ coreutils glibc git nix-tools cabal-install nix-prefetch-git ]}"
 
-  ${script}
+    ${script}
 
-  git add .
-  git commit --allow-empty -m "Automatic update for $(date)"
+    git add .
+    git commit --allow-empty -m "Automatic update for $(date)"
 
-  rev=$(git rev-parse HEAD)
+    rev=$(git rev-parse HEAD)
 
-  git push
+    if [ -f ${tokenFile} ];
+      echo "Authenticating as ${githubUser}"
+      auth="${githubUser}:$(head -n1 ${tokenFile})@"
+    else
+      echo "There is no GitHub token in ${tokenFile}"
+      auth=""
+    fi
 
-  cd ..
+    git push "https://''${auth}${repo}"
 
-  nix-prefetch-git https://github.com/input-output-hk/${name}.nix.git --rev "$rev" | tee ${name}-src.json
-''
+    cd ..
+
+    nix-prefetch-git https://${repo} --rev "$rev" | tee ${name}-src.json
+  ''