tasks: automate nixos-install

tasks.py

@@ -3,8 +3,10 @@
 from invoke import task
 
 import sys
-from typing import List
+from typing import List, Any
 from deploy_nixos import DeployHost, DeployGroup
+import subprocess
+import json
 
 
 def deploy_nixos(hosts: List[DeployHost]) -> None:
@@ -22,8 +24,87 @@ def deploy_nixos(hosts: List[DeployHost]) -> None:
     g.run_function(deploy)
 
 
+def sfdisk_json(host: DeployHost, dev: str) -> List[Any]:
+    out = host.run(f"sfdisk --json {dev}", stdout=subprocess.PIPE)
+    data = json.loads(out.stdout)
+    return data["partitiontable"]["partitions"]
 
-def get_hosts(hosts: str):
+
+def _format_disks(host: DeployHost, devices: List[str]) -> None:
+    assert len(devices) == 1 or len(devices) == 2, "we only support single devices or mirror raids at the moment"
+    # format disk with as follow:
+    # - partition 1 will be the boot partition, needed for legacy (BIOS) boot
+    # - partition 2 is for boot partition
+    # - partition 3 takes up the rest of the space and is for the system
+    for device in devices:
+        host.run(f"sgdisk -Z -n 1:2048:4095 -n 2:4096:+2G -N 3 -t 1:ef02 -t 2:8304 -t 3:8304 {device}")
+
+    # create mdadm raid for /boot with ext4
+    if len(devices) == 2:
+        boot_parts = []
+        root_parts = []
+        for dev in devices:
+            # use partuuids as they are more stable than device names
+            partitions = sfdisk_json(host, dev)
+            boot_parts.append(partitions[1]["node"])
+            root_parts.append(f"/dev/disk/by-partuuid/{partitions[2]['uuid'].lower()}")
+
+        host.run(f"mdadm --create --verbose /dev/md127 --raid-devices=2 --level=1 {' '.join(boot_parts)}")
+        host.run(f"zpool create zroot -O acltype=posixacl -O xattr=sa -O compression=lz4 mirror {' '.join(root_parts)}")
+        boot = "/dev/md127"
+    else:
+        partitions = sfdisk_json(host, devices[0])
+        boot = partitions[1]["node"]
+        uuid = partitions[2]["uuid"].lower()
+        root_part = f"/dev/disk/by-partuuid/{uuid}"
+        host.run(f"zpool create zroot -O acltype=posixacl -O xattr=sa -O compression=lz4 -O atime=off {root_part}")
+
+    host.run(f"partprobe")
+    host.run(f"mkfs.ext4 -F {boot}")
+
+    # setup zfs dataset
+    host.run(f"zfs create -o mountpoint=none zroot/root")
+    host.run(f"zfs create -o mountpoint=legacy zroot/root/nixos")
+    host.run(f"zfs create -o mountpoint=legacy zroot/root/home")
+
+    ## and finally mount
+    host.run(f"mount -t zfs zroot/root/nixos /mnt")
+    host.run(f"mkdir /mnt/home /mnt/boot")
+    host.run(f"mount -t zfs zroot/root/home /mnt/home")
+    host.run(f"mount -t ext4 /dev/md127 /mnt/boot")
+
+
+@task
+def format_disks(c, hosts = "", disks = ""):
+    """
+    Format disks with zfs
+    """
+    _format_disks(get_hosts(hosts)[0], disks.split(","))
+
+
+@task
+def setup_secret(c, hosts = ""):
+    """
+    Setup SSH key and print age key for sops-nix
+    """
+    for h in get_hosts(hosts):
+        h.run("install -m600 -D /etc/ssh/ssh_host_ed25519_key /mnt/etc/ssh/ssh_host_ed25519_key")
+        print(h.host)
+        h.run("nix-shell -p ssh-to-age --run 'cat /etc/ssh/ssh_host_ed25519_key.pub | ssh-to-age'")
+
+
+@task
+def nixos_install(c, hosts = ""):
+    """
+    Run NixOS install
+    """
+    for h in get_hosts(hosts):
+        h.run("nix-shell -p git --run 'git clone https://github.com/nix-community/infra && cd infra && nix-shell'")
+        hostname = h.host.replace('.nix-community.org', '')
+        h.run(f"cd /root/infra && nixos-install --system $(nix-build -A {hostname}-system)")
+
+
+def get_hosts(hosts: str) -> List[DeployHost]:
     if hosts == "":
         return [DeployHost(f"build{n + 1}.nix-community.org") for n in range(4)]