Add BuildArg key to quadlets

docs/source/markdown/podman-systemd.unit.5.md

@@ -1708,6 +1708,7 @@ Valid options for `[Build]` are listed below:
 | Annotation=annotation=value         | --annotation=annotation=value               |
 | Arch=aarch64                        | --arch=aarch64                              |
 | AuthFile=/etc/registry/auth\.json   | --authfile=/etc/registry/auth\.json         |
+| BuildArg=foo=bar                    | --build-arg foo=bar                         |
 | ContainersConfModule=/etc/nvd\.conf | --module=/etc/nvd\.conf                     |
 | DNS=192.168.55.1                    | --dns=192.168.55.1                          |
 | DNSOption=ndots:1                   | --dns-option=ndots:1                        |
@@ -1750,6 +1751,14 @@ Path of the authentication file.
 
 This is equivalent to the `--authfile` option of `podman build`.
 
+### `BuildArg=`
+
+Specifies a build argument and its value in the same way environment variables are
+(e.g., env=*value*), but it is not added to the environment variable list in the
+resulting image's configuration. Can be listed multiple times.
+
+This is equivalent to the `--build-arg` option of `podman build`.
+
 ### `ContainersConfModule=`
 
 Load the specified containers.conf(5) module. Equivalent to the Podman `--module` option.
@@ -2157,7 +2166,7 @@ Yaml=/opt/k8s/deployment.yml
 WantedBy=multi-user.target default.target
 ```
 
-Example for locally built image to be used in a container:
+Example for locally built image to be used in a container with build-specific arguments:
 
 `test.build`
 ```
@@ -2169,6 +2178,9 @@ ImageTag=localhost/imagename
 # expecting to find a Containerfile/Dockerfile
 # + other files needed to build the image
 SetWorkingDirectory=unit
+# Set build arguments VERSION and DEBUG
+BuildArg=VERSION=1.0 \
+          DEBUG=false
 ```
 
 `test.container`

pkg/systemd/quadlet/quadlet.go

@@ -63,6 +63,7 @@ const (
 	KeyArch                  = "Arch"
 	KeyAuthFile              = "AuthFile"
 	KeyAutoUpdate            = "AutoUpdate"
+	KeyBuildArg              = "BuildArg"
 	KeyCertDir               = "CertDir"
 	KeyCgroupsMode           = "CgroupsMode"
 	KeyConfigMap             = "ConfigMap"
@@ -433,6 +434,7 @@ var (
 				KeyAnnotation:           true,
 				KeyArch:                 true,
 				KeyAuthFile:             true,
+				KeyBuildArg:             true,
 				KeyContainersConfModule: true,
 				KeyDNS:                  true,
 				KeyDNSOption:            true,
@@ -1391,6 +1393,7 @@ func ConvertBuild(build *parser.UnitFile, unitsInfoMap map[string]*UnitInfo, isU
 	lookupAndAddAllStrings(build, BuildGroup, allStringKeys, podman)
 
 	keyValKeys := map[string]string{
+		KeyBuildArg:    "--build-arg",
 		KeyEnvironment: "--env",
 		KeyLabel:       "--label",
 		KeyAnnotation:  "--annotation",

test/e2e/quadlet/buildarg.build

@@ -0,0 +1,13 @@
+## assert-podman-args "--build-arg" "FOO=BAR"
+## assert-podman-args "--build-arg" "BIZ=BAZ"
+## assert-podman-args "--build-arg" "MULTIPLE=ARGUMENTS"
+## assert-podman-args "--build-arg" "WORKS=FINE"
+
+
+[Build]
+ImageTag=image:latest
+SetWorkingDirectory=unit
+BuildArg=FOO=BAR
+BuildArg=BIZ=BAZ
+BuildArg=MULTIPLE=ARGUMENTS \
+  WORKS=FINE

test/e2e/quadlet_test.go

@@ -1059,6 +1059,7 @@ BOGUS=foo
 		Entry("Build - Multiple Tags", "multiple-tags.build"),
 		Entry("Build - Network Key host", "network.build"),
 		Entry("Build - PodmanArgs", "podmanargs.build"),
+		Entry("Build - BuildArg Key", "buildarg.build"),
 		Entry("Build - Pull Key", "pull.build"),
 		Entry("Build - Secrets", "secrets.build"),
 		Entry("Build - SetWorkingDirectory is absolute path", "setworkingdirectory-is-abs.build"),