Enable libexec artifacts (#408)

* Enable libexec artifacts

This commit allows the user to specify artifacts to be installed under
`usr/libexec`. I used the following documentation as a guide:

https://refspecs.linuxfoundation.org/FHS_3.0/fhs/ch04s07.html#:~:text=Purpose,subdirectory%20under%20%2Fusr%2Flibexec%20.

Below, you can see at a glance what the behavior of various settings
will be. The following examples assume we are building a spec with
top-level `name: docker`. The subpath field defaults to the package
name.

```yaml
 # goes to /usr/libexec/docker/docker-compose
libexec:
  bin/docker-compose:

 # goes to /usr/libexec/docker/cli-plugins/docker-compose
libexec:
  bin/docker-compose:
    subpath: docker/cli-plugins

 # goes to /usr/libexec/something_else/cli-plugins/docker-compose
libexec:
  bin/docker-compose:
    subpath: something_else/cli-plugins

 # goes to /usr/libexec/docker/cli-plugins/hello
libexec:
  bin/docker-compose:
    subpath: docker/cli-plugins
    name: hello

 # goes to /usr/libexec/docker/hello
libexec:
  bin/docker-compose:
    name: hello

```

Signed-off-by: Peter Engelbert <pmengelbert@gmail.com>

artifacts.go

@@ -12,6 +12,8 @@ import (
 type Artifacts struct {
 	// Binaries is the list of binaries to include in the package.
 	Binaries map[string]ArtifactConfig `yaml:"binaries,omitempty" json:"binaries,omitempty"`
+	// Libexec is the list of additional binaries that may be invoked by the main package binary.
+	Libexec map[string]ArtifactConfig `yaml:"libexec,omitempty" json:"libexec,omitempty"`
 	// Manpages is the list of manpages to include in the package.
 	Manpages map[string]ArtifactConfig `yaml:"manpages,omitempty" json:"manpages,omitempty"`
 	// DataDirs is a list of read-only architecture-independent data files, to be placed in /usr/share/

docs/spec.schema.json

@@ -76,6 +76,13 @@
 					"type": "object",
 					"description": "Binaries is the list of binaries to include in the package."
 				},
+				"libexec": {
+					"additionalProperties": {
+						"$ref": "#/$defs/ArtifactConfig"
+					},
+					"type": "object",
+					"description": "Libexec is the list of additional binaries that may be invoked by the main package binary."
+				},
 				"manpages": {
 					"additionalProperties": {
 						"$ref": "#/$defs/ArtifactConfig"

frontend/deb/debroot.go

@@ -452,6 +452,16 @@ func createInstallScripts(worker llb.State, spec *dalec.Spec, dir string) []llb.
 		}
 	}
 
+	if len(spec.Artifacts.Libexec) > 0 {
+		sorted := dalec.SortMapKeys(spec.Artifacts.Libexec)
+		for _, key := range sorted {
+			cfg := spec.Artifacts.Libexec[key]
+			resolved := cfg.ResolveName(key)
+			targetDir := filepath.Join(`/usr/libexec`, cfg.SubPath)
+			writeInstall(key, targetDir, resolved)
+		}
+	}
+
 	if len(spec.Artifacts.Libs) > 0 {
 		sorted := dalec.SortMapKeys(spec.Artifacts.Libs)
 		for _, key := range sorted {

frontend/rpm/template.go

@@ -499,6 +499,14 @@ func (w *specWrapper) Install() fmt.Stringer {
 		}
 	}
 
+	if w.Spec.Artifacts.Libexec != nil {
+		libexecFileKeys := dalec.SortMapKeys(w.Spec.Artifacts.Libexec)
+		for _, k := range libexecFileKeys {
+			le := w.Spec.Artifacts.Libexec[k]
+			copyArtifact(`%{buildroot}/%{_libexecdir}`, k, &le)
+		}
+	}
+
 	configKeys := dalec.SortMapKeys(w.Spec.Artifacts.ConfigFiles)
 	for _, c := range configKeys {
 		cfg := w.Spec.Artifacts.ConfigFiles[c]
@@ -599,6 +607,16 @@ func (w *specWrapper) Files() fmt.Stringer {
 		}
 	}
 
+	if w.Spec.Artifacts.Libexec != nil {
+		dataKeys := dalec.SortMapKeys(w.Spec.Artifacts.Libexec)
+		for _, k := range dataKeys {
+			le := w.Spec.Artifacts.Libexec[k]
+			targetDir := filepath.Join(`%{_libexecdir}`, le.SubPath)
+			fullPath := filepath.Join(targetDir, le.ResolveName(k))
+			fmt.Fprintln(b, fullPath)
+		}
+	}
+
 	configKeys := dalec.SortMapKeys(w.Spec.Artifacts.ConfigFiles)
 	for _, c := range configKeys {
 		cfg := w.Spec.Artifacts.ConfigFiles[c]

test/azlinux_test.go

@@ -1022,6 +1022,110 @@ Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/boot
 		})
 	})
 
+	t.Run("test libexec file installation", func(t *testing.T) {
+		t.Parallel()
+		spec := &dalec.Spec{
+			Name:        "libexec-test",
+			Version:     "0.0.1",
+			Revision:    "1",
+			License:     "MIT",
+			Website:     "https://github.com/azure/dalec",
+			Vendor:      "Dalec",
+			Packager:    "Dalec",
+			Description: "Should install specified data files",
+			Sources: map[string]dalec.Source{
+				"no_name_no_subpath": {
+					Inline: &dalec.SourceInline{
+						File: &dalec.SourceInlineFile{
+							Contents:    "#!/usr/bin/env bash\necho hello world",
+							Permissions: 0o755,
+						},
+					},
+				},
+				"name_only": {
+					Inline: &dalec.SourceInline{
+						File: &dalec.SourceInlineFile{
+							Contents:    "#!/usr/bin/env bash\necho hello world",
+							Permissions: 0o755,
+						},
+					},
+				},
+				"name_and_subpath": {
+					Inline: &dalec.SourceInline{
+						File: &dalec.SourceInlineFile{
+							Contents:    "#!/usr/bin/env bash\necho hello world",
+							Permissions: 0o755,
+						},
+					},
+				},
+				"subpath_only": {
+					Inline: &dalec.SourceInline{
+						File: &dalec.SourceInlineFile{
+							Contents:    "#!/usr/bin/env bash\necho hello world",
+							Permissions: 0o755,
+						},
+					},
+				},
+				"nested_subpath": {
+					Inline: &dalec.SourceInline{
+						File: &dalec.SourceInlineFile{
+							Contents:    "#!/usr/bin/env bash\necho hello world",
+							Permissions: 0o755,
+						},
+					},
+				},
+			},
+			Build: dalec.ArtifactBuild{},
+			Artifacts: dalec.Artifacts{
+				Binaries: map[string]dalec.ArtifactConfig{
+					"no_name_no_subpath": {},
+				},
+				Libexec: map[string]dalec.ArtifactConfig{
+					"no_name_no_subpath": {},
+					"name_only": {
+						Name: "this_is_the_name_only",
+					},
+					"name_and_subpath": {
+						SubPath: "subpath",
+						Name:    "custom_name",
+					},
+					"subpath_only": dalec.ArtifactConfig{
+						SubPath: "custom",
+					},
+					"nested_subpath": dalec.ArtifactConfig{
+						SubPath: "libexec-test/abcdefg",
+					},
+				},
+			},
+		}
+
+		testEnv.RunTest(ctx, t, func(ctx context.Context, client gwclient.Client) {
+			req := newSolveRequest(withBuildTarget(testConfig.Target.Container), withSpec(ctx, t, spec))
+			res := solveT(ctx, t, client, req)
+
+			ref, err := res.SingleRef()
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if err := validatePathAndPermissions(ctx, ref, "/usr/libexec/no_name_no_subpath", 0o755); err != nil {
+				t.Fatal(err)
+			}
+			if err := validatePathAndPermissions(ctx, ref, "/usr/libexec/this_is_the_name_only", 0o755); err != nil {
+				t.Fatal(err)
+			}
+			if err := validatePathAndPermissions(ctx, ref, "/usr/libexec/subpath/custom_name", 0o755); err != nil {
+				t.Fatal(err)
+			}
+			if err := validatePathAndPermissions(ctx, ref, "/usr/libexec/custom/subpath_only", 0o755); err != nil {
+				t.Fatal(err)
+			}
+			if err := validatePathAndPermissions(ctx, ref, "/usr/libexec/libexec-test/abcdefg/nested_subpath", 0o755); err != nil {
+				t.Fatal(err)
+			}
+		})
+	})
+
 	t.Run("test config files handled", func(t *testing.T) {
 		t.Parallel()
 		spec := &dalec.Spec{

website/docs/artifacts.md

@@ -45,6 +45,32 @@ artifacts:
 You may use a trailing wildcard to specify multiple binaries in a directory,
 though behavior may differ between different OS's/distros.
 
+### Libexec
+
+Libexec files are additional executable files that may be executed by one of
+the main package executables. On Linux these would typically get installed into
+`/usr/libexec/` or `/usr/libexec/<main-executable-name>`.
+
+Files under libexec are a mapping of file path to [artifact configuration](#artifact-configuration).
+If `subpath` is not supplied, the artifact will be installed in `/usr/libexec`
+directly. The file path is the path to a file that must be available after the
+build section has finished. This path is relative to the working directory of
+the build phase *before* any directory changes are made.
+
+Example:
+
+```yaml
+name: my_package
+
+artifacts:
+  # the following config will install my_bin at /usr/libexec/my package/my_bin
+  libexec:
+    src/my_bin:
+```
+
+You may use a trailing wildcard to specify multiple binaries in a directory,
+though behavior may differ between different OS's/distros.
+
 ### Manpages
 
 Manpages is short for manual pages.