re-setup nix.conf after installation

.github/workflows/test.yml

@@ -17,8 +17,8 @@ jobs:
     - run: yarn test
     - name: Install Nix
       uses: ./
-    - run: nix-build test.nix
     - run: nix-env -iA cachix -f https://github.com/NixOS/nixpkgs/tarball/ab5863afada3c1b50fc43bf774b75ea71b287cde
     - run: cat /etc/nix/nix.conf
     # cachix should be available and be able to configure a cache
     - run: cachix use cachix
+    - run: nix-build test.nix

lib/main.js

@@ -20,18 +20,23 @@ const core = __importStar(require("@actions/core"));
 const exec = __importStar(require("@actions/exec"));
 const tc = __importStar(require("@actions/tool-cache"));
 const os_1 = require("os");
+function nixConf() {
+    return __awaiter(this, void 0, void 0, function* () {
+        // Workaround a segfault: https://github.com/NixOS/nix/issues/2733
+        yield exec.exec("sudo", ["mkdir", "-p", "/etc/nix"]);
+        yield exec.exec("sudo", ["sh", "-c", "echo http2 = false >> /etc/nix/nix.conf"]);
+        // Set jobs to number of cores
+        yield exec.exec("sudo", ["sh", "-c", "echo max-jobs = auto >> /etc/nix/nix.conf"]);
+        // Allow binary caches for runner user
+        yield exec.exec("sudo", ["sh", "-c", "echo trusted-users = root runner >> /etc/nix/nix.conf"]);
+    });
+}
 function run() {
     return __awaiter(this, void 0, void 0, function* () {
         try {
             const PATH = process.env.PATH;
             const INSTALL_PATH = '/opt/nix';
-            // Workaround a segfault: https://github.com/NixOS/nix/issues/2733
+            yield nixConf();
-            yield exec.exec("sudo", ["mkdir", "-p", "/etc/nix"]);
-            yield exec.exec("sudo", ["sh", "-c", "echo http2 = false >> /etc/nix/nix.conf"]);
-            // Set jobs to number of cores
-            yield exec.exec("sudo", ["sh", "-c", "echo max-jobs = auto >> /etc/nix/nix.conf"]);
-            // Allow binary caches for runner user
-            yield exec.exec("sudo", ["sh", "-c", "echo trusted-users = root runner >> /etc/nix/nix.conf"]);
             // Catalina workaround https://github.com/NixOS/nix/issues/2925
             if (os_1.type() == "Darwin") {
                 yield exec.exec("sudo", ["sh", "-c", `echo \"nix\t${INSTALL_PATH}\"  >> /etc/synthetic.conf`]);
@@ -48,6 +53,10 @@ function run() {
             // TODO: retry due to all the things that go wrong
             const nixInstall = yield tc.downloadTool('https://nixos.org/nix/install');
             yield exec.exec("sh", [nixInstall, "--daemon"]);
+            // write nix.conf again as installation overwrites it, reload the daemon to pick up changes
+            yield nixConf();
+            yield exec.exec("sudo", ["pkill", "-HUP", "nix-daemon"]);
+            // setup env
             core.exportVariable('PATH', `${PATH}:/nix/var/nix/profiles/default/bin:/nix/var/nix/profiles/per-user/runner/profile/bin`);
             core.exportVariable('NIX_PATH', `/nix/var/nix/profiles/per-user/root/channels`);
             if (os_1.type() == "Darwin") {

src/main.ts

@@ -3,11 +3,7 @@ import * as exec from '@actions/exec';
 import * as tc from '@actions/tool-cache';
 import {type} from 'os';
 
-async function run() {
+async function nixConf() {
-  try {
-    const PATH = process.env.PATH;  
-    const INSTALL_PATH = '/opt/nix';
-
     // Workaround a segfault: https://github.com/NixOS/nix/issues/2733
     await exec.exec("sudo", ["mkdir", "-p", "/etc/nix"]);
     await exec.exec("sudo", ["sh", "-c", "echo http2 = false >> /etc/nix/nix.conf"]);
@@ -17,6 +13,14 @@ async function run() {
 
     // Allow binary caches for runner user
     await exec.exec("sudo", ["sh", "-c", "echo trusted-users = root runner >> /etc/nix/nix.conf"]);
+}
+
+async function run() {
+  try {
+    const PATH = process.env.PATH;  
+    const INSTALL_PATH = '/opt/nix';
+ 
+    await nixConf();
 
     // Catalina workaround https://github.com/NixOS/nix/issues/2925
     if (type() == "Darwin") {
@@ -37,13 +41,19 @@ async function run() {
     // TODO: retry due to all the things that go wrong
     const nixInstall = await tc.downloadTool('https://nixos.org/nix/install');
     await exec.exec("sh", [nixInstall, "--daemon"]);
+
+    // write nix.conf again as installation overwrites it, reload the daemon to pick up changes
+    await nixConf();
+    await exec.exec("sudo", ["pkill", "-HUP", "nix-daemon"]);
+
+    // setup env
     core.exportVariable('PATH', `${PATH}:/nix/var/nix/profiles/default/bin:/nix/var/nix/profiles/per-user/runner/profile/bin`)
     core.exportVariable('NIX_PATH', `/nix/var/nix/profiles/per-user/root/channels`)
-
     if (type() == "Darwin") {
       // macOS needs certificates hints
       core.exportVariable('NIX_SSL_CERT_FILE', '/nix/var/nix/profiles/default/etc/ssl/certs/ca-bundle.crt');
     }
+
   } catch (error) {
     core.setFailed(`Action failed with error: ${error}`);
     throw(error);