osbuild/result: parse the metadata from the rpm stage

osbuild support returning metadata about each of the stages/assembler
runs. Parse the results from the rpm stage, which contains the header
fields from the installed RPMs, in particular the MD5 sum of the RPMs in
question. This information is needed to be passed as metadata to koji
when uploading images.

Signed-off-by: Tom Gundersen <teg@jklm.no>

internal/osbuild/result.go

@@ -6,33 +6,74 @@ import (
 	"io"
 )
 
-type assembler struct {
+type rawAssemblerResult struct {
 	Name    string          `json:"name"`
 	Options json.RawMessage `json:"options"`
 	Success bool            `json:"success"`
 	Output  string          `json:"output"`
 }
 
-type stage struct {
-	Name    string          `json:"name"`
-	Options json.RawMessage `json:"options"`
-	Success bool            `json:"success"`
-	Output  string          `json:"output"`
+type StageResult struct {
+	Name     string          `json:"name"`
+	Options  json.RawMessage `json:"options"`
+	Success  bool            `json:"success"`
+	Output   string          `json:"output"`
+	Metadata StageMetadata   `json:"metadata"`
 }
 
-type build struct {
-	Stages  []stage `json:"stages"`
-	TreeID  string  `json:"tree_id"`
-	Success bool    `json:"success"`
+// StageMetadata specify the metadata of a given stage-type.
+type StageMetadata interface {
+	isStageMetadata()
+}
+
+type rawStageResult struct {
+	Name     string          `json:"name"`
+	Options  json.RawMessage `json:"options"`
+	Success  bool            `json:"success"`
+	Output   string          `json:"output"`
+	Metadata json.RawMessage `json:"metadata"`
+}
+
+type buildResult struct {
+	Stages  []StageResult `json:"stages"`
+	TreeID  string        `json:"tree_id"`
+	Success bool          `json:"success"`
 }
 
 type Result struct {
-	TreeID    string     `json:"tree_id"`
-	OutputID  string     `json:"output_id"`
-	Build     *build     `json:"build"`
-	Stages    []stage    `json:"stages"`
-	Assembler *assembler `json:"assembler"`
-	Success   bool       `json:"success"`
+	TreeID    string              `json:"tree_id"`
+	OutputID  string              `json:"output_id"`
+	Build     *buildResult        `json:"build"`
+	Stages    []StageResult       `json:"stages"`
+	Assembler *rawAssemblerResult `json:"assembler"`
+	Success   bool                `json:"success"`
+}
+
+func (result *StageResult) UnmarshalJSON(data []byte) error {
+	var rawStageResult rawStageResult
+	err := json.Unmarshal(data, &rawStageResult)
+	if err != nil {
+		return err
+	}
+	var metadata StageMetadata
+	switch rawStageResult.Name {
+	case "org.osbuild.rpm":
+		metadata = new(RPMStageMetadata)
+		err = json.Unmarshal(rawStageResult.Metadata, metadata)
+		if err != nil {
+			return err
+		}
+	default:
+		metadata = nil
+	}
+
+	result.Name = rawStageResult.Name
+	result.Options = rawStageResult.Options
+	result.Success = rawStageResult.Success
+	result.Output = rawStageResult.Output
+	result.Metadata = metadata
+
+	return nil
 }
 
 func (cr *Result) Write(writer io.Writer) error {

internal/osbuild/result_test.go

@@ -2,29 +2,101 @@ package osbuild
 
 import (
 	"bytes"
+	"encoding/json"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 )
 
+func TestUnmarshall(t *testing.T) {
+	resultRaw := `{
+		"success": true,
+		"build": {
+		  "success": true,
+		  "stages": [
+			{
+			  "name": "org.osbuild.rpm",
+			  "id": "9eb0a6f6fd6e2995e107f5bcc6aa3b19643b02ec133bdc8a8ac614860b1bbf2d",
+			  "success": true,
+			  "output": "Building...",
+			  "metadata": {
+				"packages": [
+				  {
+					"name": "libgcc",
+					"version": "10.0.1",
+					"release": "0.11.fc32",
+					"epoch": null,
+					"arch": "x86_64",
+					"sigmd5": "84fc907a5047aeebaf8da1642925a417"
+				  },
+				  {
+					"name": "whois-nls",
+					"version": "5.5.6",
+					"release": "1.fc32",
+					"epoch": null,
+					"arch": "noarch",
+					"sigmd5": "f868cd02046630c8ce3a9c48820e2437"
+				  }
+				]
+			  }
+			}
+		  ]
+		}
+	  }`
+
+	var result Result
+	err := json.Unmarshal([]byte(resultRaw), &result)
+	assert.NoError(t, err)
+
+	assert.Equal(t, result.Build.Stages[0].Name, "org.osbuild.rpm")
+	metadata, ok := result.Build.Stages[0].Metadata.(*RPMStageMetadata)
+	assert.True(t, ok)
+	package1 := metadata.Packages[0]
+	assert.Equal(t, package1.Name, "libgcc")
+	assert.Nil(t, package1.Epoch)
+	assert.Equal(t, package1.Version, "10.0.1")
+	assert.Equal(t, package1.Release, "0.11.fc32")
+	assert.Equal(t, package1.Arch, "x86_64")
+	assert.Equal(t, package1.SigMD5, "84fc907a5047aeebaf8da1642925a417")
+}
+
 func TestWriteFull(t *testing.T) {
 
 	const testOptions = `{"msg": "test"}`
 
-	testStage := stage{
-		Name:    "testStage",
+	dnfStage := StageResult{
+		Name:    "org.osbuild.rpm",
+		Options: []byte(testOptions),
+		Success: true,
+		Output:  "Finished",
+		Metadata: RPMStageMetadata{
+			Packages: []RPMPackageMetadata{
+				{
+					Name:    "foobar",
+					Epoch:   nil,
+					Version: "1",
+					Release: "1",
+					Arch:    "noarch",
+					SigMD5:  "deadbeef",
+				},
+			},
+		},
+	}
+
+	testStage := StageResult{
+		Name:    "org.osbuild.test",
 		Options: []byte(testOptions),
 		Success: true,
 		Output:  "Finished",
 	}
 
-	testBuild := build{
-		Stages:  []stage{testStage},
+	testBuild := buildResult{
+		Stages:  []StageResult{testStage},
 		TreeID:  "treeID",
 		Success: true,
 	}
 
-	testAssembler := assembler{
+	testAssembler := rawAssemblerResult{
 		Name:    "testAssembler",
 		Options: []byte(testOptions),
 		Success: true,
@@ -35,7 +107,7 @@ func TestWriteFull(t *testing.T) {
 		TreeID:    "TreeID",
 		OutputID:  "OutputID",
 		Build:     &testBuild,
-		Stages:    []stage{testStage},
+		Stages:    []StageResult{dnfStage},
 		Assembler: &testAssembler,
 		Success:   true,
 	}
@@ -44,7 +116,7 @@ func TestWriteFull(t *testing.T) {
 	assert.NoError(t, testComposeResult.Write(&b))
 	expectedMessage :=
 		`Build pipeline:
-Stage testStage
+Stage org.osbuild.test
 {
   "msg": "test"
 }
@@ -52,7 +124,7 @@ Stage testStage
 Output:
 Finished
 Stages:
-Stage: testStage
+Stage: org.osbuild.rpm
 {
   "msg": "test"
 }

internal/osbuild/rpm_stage.go

@@ -28,3 +28,20 @@ func NewRPMStage(options *RPMStageOptions) *Stage {
 		Options: options,
 	}
 }
+
+// RPMStageMetadata gives the set of packages installed by the RPM stage
+type RPMStageMetadata struct {
+	Packages []RPMPackageMetadata `json:"packages"`
+}
+
+// RPMPackageMetadata contains the metadata extracted from one RPM header
+type RPMPackageMetadata struct {
+	Name    string  `json:"name"`
+	Version string  `json:"version"`
+	Release string  `json:"release"`
+	Epoch   *string `json:"epoch"`
+	Arch    string  `json:"arch"`
+	SigMD5  string  `json:"sigmd5"`
+}
+
+func (RPMStageMetadata) isStageMetadata() {}