platform/conf: add Butane config support

CHANGELOG.md

@@ -18,6 +18,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - kola tests `cl.cgroupv1` and `kubeadm.*.*.cgroupv1.base` that test functionality with cgroupv1 ([#298](https://github.com/flatcar-linux/mantle/pull/298))
 - Added private network support to qemu-unpriv platform ([#307](https://github.com/flatcar-linux/mantle/pull/307))
 - Ignition v3 support and tests ([#301](https://github.com/flatcar-linux/mantle/pull/301), [#311](https://github.com/flatcar-linux/mantle/pull/311))
+- Butane config support ([#318](https://github.com/flatcar-linux/mantle/pull/318))
 
 ### Changed
 - removed `packet` occurrences in favor of `equinixmetal` ([#277](https://github.com/flatcar-linux/mantle/pull/277))

go.mod

@@ -8,16 +8,17 @@ require (
 	github.com/Azure/go-autorest/autorest/azure/auth v0.5.8
 	github.com/Microsoft/azure-vhd-utils v0.0.0-20210818134022-97083698b75f
 	github.com/aws/aws-sdk-go v1.42.41
+	github.com/coreos/butane v0.14.1-0.20220401164106-6b5239299226
 	github.com/coreos/coreos-cloudinit v1.11.0
 	github.com/coreos/go-iptables v0.5.0
 	github.com/coreos/go-omaha v0.0.0-20170526203809-f8acb2d7b76c
 	github.com/coreos/go-semver v0.3.0
+	github.com/coreos/ignition/v2 v2.13.0
 	github.com/coreos/ioprogress v0.0.0-20151023204047-4637e494fd9b
 	github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f
 	github.com/digitalocean/godo v1.45.0
 	github.com/flatcar-linux/container-linux-config-transpiler v0.9.3-0.20220208152502-6e8303479682
 	github.com/flatcar-linux/ignition v0.36.2-0.20220221101037-de4e6cc9bbba
-	github.com/flatcar-linux/ignition/v2 v2.2.1-0.20220311122140-cb95c51122f5
 	github.com/godbus/dbus v0.0.0-20181025153459-66d97aec3384
 	github.com/golang/protobuf v1.5.2
 	github.com/gophercloud/gophercloud v0.0.0-20180817041643-185230dfbd12
@@ -28,7 +29,7 @@ require (
 	github.com/pin/tftp v2.1.0+incompatible
 	github.com/spf13/cobra v1.1.3
 	github.com/spf13/pflag v1.0.6-0.20210604193023-d5e0c0615ace
-	github.com/stretchr/testify v1.7.0
+	github.com/stretchr/testify v1.7.1
 	github.com/ulikunitz/xz v0.5.10
 	github.com/vincent-petithory/dataurl v1.0.0
 	github.com/vishvananda/netlink v1.1.1-0.20210330154013-f5de75959ad5
@@ -61,10 +62,11 @@ require (
 	github.com/alecthomas/units v0.0.0-20210208195552-ff826a37aa15 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.1.1 // indirect
-	github.com/coreos/go-json v0.0.0-20211020211907-c63f628265de // indirect
+	github.com/clarketm/json v1.17.1 // indirect
+	github.com/coreos/go-json v0.0.0-20220325222439-31b2177291ae // indirect
 	github.com/coreos/go-systemd v0.0.0-20191104093116-d3cd4ed1dbcf // indirect
 	github.com/coreos/go-systemd/v22 v22.3.2 // indirect
-	github.com/coreos/vcontext v0.0.0-20211021162308-f1dbbca7bef4 // indirect
+	github.com/coreos/vcontext v0.0.0-20220326205524-7fcaf69e7050 // indirect
 	github.com/coreos/yaml v0.0.0-20141224210557-6b16a5714269 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/dimchansky/utfbom v1.1.1 // indirect

go.sum

@@ -106,6 +106,8 @@ github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWR
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
 github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
 github.com/clarketm/json v1.14.1/go.mod h1:ynr2LRfb0fQU34l07csRNBTcivjySLLiY1YzQqKVfdo=
+github.com/clarketm/json v1.17.1 h1:U1IxjqJkJ7bRK4L6dyphmoO840P6bdhPdbbLySourqI=
+github.com/clarketm/json v1.17.1/go.mod h1:ynr2LRfb0fQU34l07csRNBTcivjySLLiY1YzQqKVfdo=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
 github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
@@ -116,13 +118,16 @@ github.com/cockroachdb/errors v1.2.4/go.mod h1:rQD95gz6FARkaKkQXUksEje/d9a6wBJoC
 github.com/cockroachdb/logtags v0.0.0-20190617123548-eb05cc24525f h1:o/kfcElHqOiXqcou5a3rIlMc7oJbMQkeLk0VQJ7zgqY=
 github.com/cockroachdb/logtags v0.0.0-20190617123548-eb05cc24525f/go.mod h1:i/u985jwjWRlyHXQbwatDASoW0RMlZ/3i9yJHE2xLkI=
 github.com/coreos/bbolt v1.3.2/go.mod h1:iRUV2dpdMOn7Bo10OQBFzIJO9kkE559Wcmn+qkEiiKk=
+github.com/coreos/butane v0.14.1-0.20220401164106-6b5239299226 h1:bFC7LN8ltkYe5xPHj/fQ4qRGbKlYy0VXimkbp7ZNjP8=
+github.com/coreos/butane v0.14.1-0.20220401164106-6b5239299226/go.mod h1:Q5DcBsHDckEZ7IgQSb1MvvkNc50dpoT1lOHdGWwCRjY=
 github.com/coreos/coreos-cloudinit v1.11.0 h1:qSLLJPaK4zavsL3ii02F2+v3P9I7JcaOW73s5+UKfw8=
 github.com/coreos/coreos-cloudinit v1.11.0/go.mod h1:hV3swhSwq+bRX5apuk57gG+3fsQacgbrZVxjPTqo0zo=
 github.com/coreos/etcd v3.3.13+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
 github.com/coreos/go-iptables v0.5.0 h1:mw6SAibtHKZcNzAsOxjoHIG0gy5YFHhypWSSNc6EjbQ=
 github.com/coreos/go-iptables v0.5.0/go.mod h1:/mVI274lEDI2ns62jHCDnCyBF9Iwsmekav8Dbxlm1MU=
-github.com/coreos/go-json v0.0.0-20211020211907-c63f628265de h1:qZvNu52Tv7Jfbgxdw3ONHf0BK9UpuSxi9FA9Y+qU5VU=
 github.com/coreos/go-json v0.0.0-20211020211907-c63f628265de/go.mod h1:lryFBkhadOfv8Jue2Vr/f/Yviw8h1DQPQojbXqEChY0=
+github.com/coreos/go-json v0.0.0-20220325222439-31b2177291ae h1:NS9LsAvb9JOCPbAgembZCQvAg0FOhQj/p6SCmWRvTRU=
+github.com/coreos/go-json v0.0.0-20220325222439-31b2177291ae/go.mod h1:lryFBkhadOfv8Jue2Vr/f/Yviw8h1DQPQojbXqEChY0=
 github.com/coreos/go-omaha v0.0.0-20170526203809-f8acb2d7b76c h1:n9z1rkyYf+OGow4mvjFHhsLxS8wLnoD0SHqDeF2/en8=
 github.com/coreos/go-omaha v0.0.0-20170526203809-f8acb2d7b76c/go.mod h1:IU76HHVFspEz6YCsXufWBCTPBPbL86JSct4XvXfZPMA=
 github.com/coreos/go-semver v0.1.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
@@ -135,12 +140,15 @@ github.com/coreos/go-systemd v0.0.0-20191104093116-d3cd4ed1dbcf/go.mod h1:F5haX7
 github.com/coreos/go-systemd/v22 v22.0.0/go.mod h1:xO0FLkIi5MaZafQlIrOotqXZ90ih+1atmu1JpKERPPk=
 github.com/coreos/go-systemd/v22 v22.3.2 h1:D9/bQk5vlXQFZ6Kwuu6zaiXJ9oTPe68++AzAJc1DzSI=
 github.com/coreos/go-systemd/v22 v22.3.2/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
+github.com/coreos/ignition/v2 v2.13.0 h1:1ouW+d0nOuPUbLjxxOCnC+dWQxynr8Mt5exqJoCD7b4=
+github.com/coreos/ignition/v2 v2.13.0/go.mod h1:HO1HWYWcvAIbHu6xewoKxPGBTyZ32FLwGIuipw5d63o=
 github.com/coreos/ioprogress v0.0.0-20151023204047-4637e494fd9b h1:mpeSDqY0vMUyJmazX0p62MrHtgwlmOf7Y8rqOYL1cmc=
 github.com/coreos/ioprogress v0.0.0-20151023204047-4637e494fd9b/go.mod h1:JIWRG8HSwVYUrjdR/JsFg7DEby0nhQcWFPIQvXJyih8=
 github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f h1:lBNOc5arjvs8E5mO2tbpBpLoyyu8B6e44T7hJy6potg=
 github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
-github.com/coreos/vcontext v0.0.0-20211021162308-f1dbbca7bef4 h1:pfSsrvbjUFGINaPGy0mm2QKQKTdq7IcbUa+nQwsz2UM=
 github.com/coreos/vcontext v0.0.0-20211021162308-f1dbbca7bef4/go.mod h1:HckqHnP/HI41vS0bfVjJ20u6jD0biI5+68QwZm5Xb9U=
+github.com/coreos/vcontext v0.0.0-20220326205524-7fcaf69e7050 h1:Je4Sor/M7mqtqardljqFVNzDtOd2GQtUDFMXu8HKQb4=
+github.com/coreos/vcontext v0.0.0-20220326205524-7fcaf69e7050/go.mod h1:HckqHnP/HI41vS0bfVjJ20u6jD0biI5+68QwZm5Xb9U=
 github.com/coreos/yaml v0.0.0-20141224210557-6b16a5714269 h1:/1sjrpK5Mb6IwyFOKd+u7321tXfNAsj0Ci8CivZmSlo=
 github.com/coreos/yaml v0.0.0-20141224210557-6b16a5714269/go.mod h1:Bl1D/T9QJhVdu6eFoLrGxN90+admDLGaLz2HXH/VzDc=
 github.com/cpuguy83/go-md2man/v2 v2.0.0/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
@@ -170,13 +178,9 @@ github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/flatcar-linux/container-linux-config-transpiler v0.9.3-0.20220208152502-6e8303479682 h1:CiIJbwa0iC52LGviALcCtpnLpNa2hYXEdM64xFgALa0=
 github.com/flatcar-linux/container-linux-config-transpiler v0.9.3-0.20220208152502-6e8303479682/go.mod h1:AGVTulMzeIKwurV9ExYH3UiokET1Ur65g+EIeRDMwzM=
-github.com/flatcar-linux/ign-converter v0.1.1-0.20220311112608-f121a881f370/go.mod h1:t/kcw0CQ/uKMCyZwDAzuwMO3CShxaimEJhQzLGCsb3Y=
 github.com/flatcar-linux/ignition v0.36.1/go.mod h1:0jS5n4AopgOdwgi7QDo5MFgkMx/fQUDYjuxlGJC1Txg=
 github.com/flatcar-linux/ignition v0.36.2-0.20220221101037-de4e6cc9bbba h1:HiTCL7737Hi944kXfLN8ReGoJtAiibGIsCk3MGlYy9M=
 github.com/flatcar-linux/ignition v0.36.2-0.20220221101037-de4e6cc9bbba/go.mod h1:JzHCIdCu9dy0xtezyBit/aOY4QIlJ12UYU6nXNPnnRE=
-github.com/flatcar-linux/ignition/v2 v2.2.1-0.20220302150437-ce14e51676e9/go.mod h1:n076OVuGbg6f+j3YYoxFCjRyMU2hxsx6Q4Gy0xwO7cM=
-github.com/flatcar-linux/ignition/v2 v2.2.1-0.20220311122140-cb95c51122f5 h1:k7xpW9MfyAxjsoA0HW6nnHlQnlNlPrPhHPNuT4uf7Xo=
-github.com/flatcar-linux/ignition/v2 v2.2.1-0.20220311122140-cb95c51122f5/go.mod h1:C0FynALB9lic4GBqxCuNqUqfZlny9rySbFx0VVXy7uU=
 github.com/form3tech-oss/jwt-go v3.2.2+incompatible/go.mod h1:pbq4aXjuKjdthFRnoDwaVPLA+WlJuPGy+QneDUgJi2k=
 github.com/form3tech-oss/jwt-go v3.2.3+incompatible/go.mod h1:pbq4aXjuKjdthFRnoDwaVPLA+WlJuPGy+QneDUgJi2k=
 github.com/form3tech-oss/jwt-go v3.2.5+incompatible h1:/l4kBbb4/vGSsdtB5nUe8L7B9mImVMaBPw9L/0TBHU8=
@@ -451,8 +455,9 @@ github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXf
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
-github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/subosito/gotenv v1.2.0/go.mod h1:N0PQaV/YGNqwC0u51sEeR/aUtSLEXKX9iv69rRypqCw=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20190109142713-0ad062ec5ee5/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20201229170055-e5319fda7802/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
@@ -526,7 +531,6 @@ go.uber.org/zap v1.10.0/go.mod h1:vwi/ZaCAaUcBkycHslxD9B2zi4UTXhF60s6SWpuDF0Q=
 go.uber.org/zap v1.17.0 h1:MTjgFu6ZLKvY6Pvaqk97GlxNBuMpV4Hy/3P6tRGlI2U=
 go.uber.org/zap v1.17.0/go.mod h1:MXVU+bhUf/A7Xi2HNOnopQOrmycQ5Ih87HtOu4q5SSo=
 go4.org v0.0.0-20160314031811-03efcb870d84/go.mod h1:MkTOUMDaeVYJUOUsaDXIhWPZYa1yOyC1qaOBpL57BhE=
-go4.org v0.0.0-20200104003542-c7e774b10ea0/go.mod h1:MkTOUMDaeVYJUOUsaDXIhWPZYa1yOyC1qaOBpL57BhE=
 go4.org v0.0.0-20201209231011-d4a079459e60 h1:iqAGo78tVOJXELHQFRjR6TMwItrvXH4hrGJ32I/NFF8=
 go4.org v0.0.0-20201209231011-d4a079459e60/go.mod h1:CIiUVy99QCPfoE13bO4EZaz5GZMZXMSBGhxRdsvzbkg=
 golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=

kola/tests/ignition/kernel.go

@@ -14,14 +14,12 @@ func init() {
 		Name:        "cl.ignition.kargs",
 		Run:         check,
 		ClusterSize: 1,
-		UserData: conf.Ignition(`{
-		  "ignition": {
-		    "version": "3.3.0"
-		  },
-		  "kernelArguments": {
-		    "shouldExist": ["quiet"]
-		  }
-		}`),
+		UserData: conf.Butane(`---
+variant: flatcar
+version: 1.0.0
+kernel_arguments:
+  should_exist:
+    - quiet`),
 		MinVersion: semver.Version{Major: 3185},
 		// The additional reboot causes a large waiting time
 		// and it's enough to test this on QEMU

kola/tests/ignition/luks.go

@@ -17,28 +17,19 @@ func init() {
 		ClusterSize: 1,
 		Distros:     []string{"cl"},
 		MinVersion:  semver.Version{Major: 3185},
-		UserData: conf.Ignition(`{
-		  "ignition": {"version": "3.2.0"},
-		  "storage": {
-		    "luks": [{
-		      "name": "data",
-		      "device": "/dev/disk/by-partlabel/USR-B"
-		    }],
-		    "filesystems": [{
-		      "path": "/var/lib/data",
-		      "device": "/dev/disk/by-id/dm-name-data",
-		      "format": "ext4",
-		      "label": "DATA"
-		    }]
-		  },
-		  "systemd": {
-		    "units": [{
-		      "name": "var-lib-data.mount",
-		      "enabled": true,
-		      "contents": "[Mount]\nWhat=/dev/disk/by-label/DATA\nWhere=/var/lib/data\nType=ext4\n\n[Install]\nWantedBy=local-fs.target"
-		    }]
-		  }
-	  	}`),
+		UserData: conf.Butane(`---
+variant: flatcar
+version: 1.0.0
+storage:
+  luks:
+    - name: data
+      device: /dev/disk/by-partlabel/USR-B
+  filesystems:
+    - path: /var/lib/data
+      device: /dev/disk/by-id/dm-name-data
+      format: ext4
+      label: DATA
+      with_mount_unit: true`),
 	})
 }
 

platform/conf/conf.go

@@ -23,7 +23,19 @@ import (
 	"reflect"
 	"strings"
 
+	butane "github.com/coreos/butane/config"
+	"github.com/coreos/butane/config/common"
 	cci "github.com/coreos/coreos-cloudinit/config"
+	ign3err "github.com/coreos/ignition/v2/config/shared/errors"
+	v3 "github.com/coreos/ignition/v2/config/v3_0"
+	v3types "github.com/coreos/ignition/v2/config/v3_0/types"
+	v31 "github.com/coreos/ignition/v2/config/v3_1"
+	v31types "github.com/coreos/ignition/v2/config/v3_1/types"
+	v32 "github.com/coreos/ignition/v2/config/v3_2"
+	v32types "github.com/coreos/ignition/v2/config/v3_2/types"
+	v33 "github.com/coreos/ignition/v2/config/v3_3"
+	v33types "github.com/coreos/ignition/v2/config/v3_3/types"
+	ign3validate "github.com/coreos/ignition/v2/config/validate"
 	"github.com/coreos/pkg/capnslog"
 	ct "github.com/flatcar-linux/container-linux-config-transpiler/config"
 	ignerr "github.com/flatcar-linux/ignition/config/shared/errors"
@@ -38,16 +50,6 @@ import (
 	v23 "github.com/flatcar-linux/ignition/config/v2_3"
 	v23types "github.com/flatcar-linux/ignition/config/v2_3/types"
 	ignvalidate "github.com/flatcar-linux/ignition/config/validate"
-	ign3err "github.com/flatcar-linux/ignition/v2/config/shared/errors"
-	v3 "github.com/flatcar-linux/ignition/v2/config/v3_0"
-	v3types "github.com/flatcar-linux/ignition/v2/config/v3_0/types"
-	v31 "github.com/flatcar-linux/ignition/v2/config/v3_1"
-	v31types "github.com/flatcar-linux/ignition/v2/config/v3_1/types"
-	v32 "github.com/flatcar-linux/ignition/v2/config/v3_2"
-	v32types "github.com/flatcar-linux/ignition/v2/config/v3_2/types"
-	v33 "github.com/flatcar-linux/ignition/v2/config/v3_3"
-	v33types "github.com/flatcar-linux/ignition/v2/config/v3_3/types"
-	ign3validate "github.com/flatcar-linux/ignition/v2/config/validate"
 	"github.com/vincent-petithory/dataurl"
 	"golang.org/x/crypto/ssh/agent"
 )
@@ -60,6 +62,7 @@ const (
 	kindIgnition
 	kindContainerLinuxConfig
 	kindScript
+	kindButane
 )
 
 var plog = capnslog.NewPackageLogger("github.com/flatcar-linux/mantle", "platform/conf")
@@ -115,6 +118,13 @@ func CloudConfig(data string) *UserData {
 	}
 }
 
+func Butane(data string) *UserData {
+	return &UserData{
+		kind: kindButane,
+		data: data,
+	}
+}
+
 func Script(data string) *UserData {
 	return &UserData{
 		kind: kindScript,
@@ -170,7 +180,7 @@ func (u *UserData) AddKey(key agent.Key) *UserData {
 }
 
 func (u *UserData) IsIgnitionCompatible() bool {
-	return u.kind == kindIgnition || u.kind == kindContainerLinuxConfig
+	return u.kind == kindIgnition || u.kind == kindContainerLinuxConfig || u.kind == kindButane
 }
 
 // Render parses userdata and returns a new Conf. It returns an error if the
@@ -299,6 +309,37 @@ func (u *UserData) Render(ctPlatform string) (*Conf, error) {
 		}
 
 		c.ignitionV23 = &ignc
+	case kindButane:
+		// CLC translation is done in two steps:
+		// * Parsing the data
+		// * Converting the CLC parsed data to Ignition types (bound to the Ignition spec version)
+		// Butane is a bit different, so we convert data directly to Ignition3.3.0 bytes, butane will
+		// take care itself to parse the variant / version of the config to do the right translation with an Ignition
+		// version >= 3.3.0
+		ignc, report, err := butane.TranslateBytes([]byte(u.data), common.TranslateBytesOptions{})
+		if err != nil {
+			return nil, fmt.Errorf("converting Butane to Ignition: %w", err)
+		}
+
+		if report.IsFatal() {
+			return nil, fmt.Errorf("converting Butane to Ignition: %s", report.String())
+		}
+
+		if len(report.Entries) > 0 {
+			plog.Warningf("parsing Butane config: %s", report.String())
+		}
+
+		// Doing that allows to benefit from existing Ignition mechanism:
+		// CopyKeys, AddSystemdUnit, etc.
+		u.data = string(ignc)
+
+		// for consistency.
+		u.kind = kindIgnition
+
+		// Config is now considered as an Ignition configuration.
+		if err := renderIgnition(); err != nil {
+			return nil, err
+		}
 	default:
 		panic("invalid kind")
 	}

platform/conf/conf_test.go

@@ -44,6 +44,7 @@ func TestConfCopyKey(t *testing.T) {
 		Ignition(`{ "ignition": { "version": "3.3.0" } }`),
 		Ignition(`{ "ignitionVersion": 1 }`),
 		CloudConfig("#cloud-config"),
+		Butane("variant: flatcar\nversion: 1.0.0"),
 	}
 
 	for i, tt := range tests {