distro: don't fall back to fedora-30

Make osbuild-composer use FromHost() directly. Everywhere else needs to
specify the distro explicitly.

Also don't panic when a distro doesn't exist. Instead, return nil. Make
sure all callers check for that.

cmd/osbuild-composer/main.go

@@ -34,14 +34,18 @@ func main() {
 	jobListener := listeners[1]
 
 	rpm := rpmmd.NewRPMMD()
-	distribution := distro.New("")
+
+	distribution, err := distro.FromHost()
+	if err != nil {
+		panic("cannot detect distro from host: " + err.Error())
+	}
 
 	var logger *log.Logger
 	if verbose {
 		logger = log.New(os.Stdout, "", 0)
 	}
 
-	store := store.New(&stateFile)
+	store := store.New(&stateFile, distribution)
 
 	jobAPI := jobqueue.New(logger, store)
 	weldrAPI := weldr.New(rpm, distribution, logger, store)

cmd/osbuild-pipeline/main.go

@@ -32,6 +32,10 @@ func main() {
 	}
 
 	d := distro.New(distroArg)
+	if d == nil {
+		panic("unknown distro: " + distroArg)
+	}
+
 	pipeline, err := d.Pipeline(blueprint, format)
 	if err != nil {
 		panic(err.Error())

internal/distro/distro.go

@@ -4,7 +4,6 @@ import (
 	"bufio"
 	"errors"
 	"io"
-	"log"
 	"os"
 	"strings"
 
@@ -44,20 +43,9 @@ func init() {
 }
 
 func New(name string) Distro {
-	if name == "" {
-		distro, err := FromHost()
-		if err == nil {
-			return distro
-		} else {
-			log.Println("cannot detect distro from host: " + err.Error())
-			log.Println("falling back to 'fedora-30'")
-			return New("fedora-30")
-		}
-	}
-
 	distro, ok := registered[name]
 	if !ok {
-		panic("unknown distro: " + name)
+		return nil
 	}
 
 	return distro
@@ -77,11 +65,12 @@ func FromHost() (Distro, error) {
 
 	name := osrelease["ID"] + "-" + osrelease["VERSION_ID"]
 
-	distro, ok := registered[name]
-	if !ok {
+	d := New(name)
+	if d == nil {
 		return nil, errors.New("unknown distro: " + name)
 	}
-	return distro, nil
+
+	return d, nil
 }
 
 func Register(name string, distro Distro) {

internal/jobqueue/api_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/osbuild/osbuild-composer/internal/blueprint"
+	"github.com/osbuild/osbuild-composer/internal/distro"
 	"github.com/osbuild/osbuild-composer/internal/jobqueue"
 	"github.com/osbuild/osbuild-composer/internal/store"
 	"github.com/osbuild/osbuild-composer/internal/test"
@@ -31,7 +32,7 @@ func TestBasic(t *testing.T) {
 	}
 
 	for _, c := range cases {
-		api := jobqueue.New(nil, store.New(nil))
+		api := jobqueue.New(nil, store.New(nil, distro.New("fedora-30")))
 
 		test.TestRoute(t, api, false, c.Method, c.Path, c.Body, c.ExpectedStatus, c.ExpectedJSON)
 	}
@@ -39,7 +40,7 @@ func TestBasic(t *testing.T) {
 
 func TestCreate(t *testing.T) {
 	id, _ := uuid.Parse("ffffffff-ffff-ffff-ffff-ffffffffffff")
-	store := store.New(nil)
+	store := store.New(nil, distro.New("fedora-30"))
 	api := jobqueue.New(nil, store)
 
 	err := store.PushCompose(id, &blueprint.Blueprint{}, "tar")
@@ -53,7 +54,7 @@ func TestCreate(t *testing.T) {
 
 func testUpdateTransition(t *testing.T, from, to string, expectedStatus int) {
 	id, _ := uuid.Parse("ffffffff-ffff-ffff-ffff-ffffffffffff")
-	store := store.New(nil)
+	store := store.New(nil, distro.New("fedora-30"))
 	api := jobqueue.New(nil, store)
 
 	if from != "VOID" {

internal/mocks/rpmmd/fixtures.go

@@ -2,12 +2,14 @@ package rpmmd_mock
 
 import (
 	"fmt"
-	"github.com/google/uuid"
-	"github.com/osbuild/osbuild-composer/internal/blueprint"
-	"github.com/osbuild/osbuild-composer/internal/rpmmd"
-	"github.com/osbuild/osbuild-composer/internal/store"
 	"sort"
 	"time"
+
+	"github.com/google/uuid"
+	"github.com/osbuild/osbuild-composer/internal/blueprint"
+	"github.com/osbuild/osbuild-composer/internal/distro"
+	"github.com/osbuild/osbuild-composer/internal/rpmmd"
+	"github.com/osbuild/osbuild-composer/internal/store"
 )
 
 type FixtureGenerator func() Fixture
@@ -56,7 +58,8 @@ func createBaseStoreFixture() *store.Store {
 
 	var date = time.Date(2019, 11, 27, 13, 19, 0, 0, time.FixedZone("UTC+1", 60*60))
 
-	s := store.New(nil)
+	d := distro.New("fedora-30")
+	s := store.New(nil, d)
 
 	s.Blueprints[bName] = b
 	s.Composes = map[uuid.UUID]store.Compose{

internal/store/store.go

@@ -35,6 +35,7 @@ type Store struct {
 	mu           sync.RWMutex // protects all fields
 	pendingJobs  chan Job
 	stateChannel chan []byte
+	distro       distro.Distro
 }
 
 // A Compose represent the task of building one image. It contains all the information
@@ -105,7 +106,7 @@ func (e *InvalidRequestError) Error() string {
 	return e.message
 }
 
-func New(stateFile *string) *Store {
+func New(stateFile *string, distro distro.Distro) *Store {
 	var s Store
 
 	if stateFile != nil {
@@ -149,6 +150,8 @@ func New(stateFile *string) *Store {
 	}
 	s.pendingJobs = make(chan Job, 200)
 
+	s.distro = distro
+
 	return &s
 }
 
@@ -448,8 +451,7 @@ func (s *Store) PushCompose(composeID uuid.UUID, bp *blueprint.Blueprint, compos
 			},
 		),
 	}
-	d := distro.New("")
-	pipeline, err := d.Pipeline(bp, composeType)
+	pipeline, err := s.distro.Pipeline(bp, composeType)
 	if err != nil {
 		return err
 	}
@@ -527,8 +529,7 @@ func (s *Store) GetImage(composeID uuid.UUID) (*Image, error) {
 		if compose.QueueStatus != "FINISHED" {
 			return nil, &InvalidRequestError{"compose was not finished"}
 		}
-		d := distro.New("")
-		name, mime, err := d.FilenameFromType(compose.OutputType)
+		name, mime, err := s.distro.FilenameFromType(compose.OutputType)
 		if err != nil {
 			panic("invalid output type")
 		}

internal/weldr/api.go

@@ -1195,8 +1195,7 @@ func (api *API) composeTypesHandler(writer http.ResponseWriter, request *http.Re
 		Types []composeType `json:"types"`
 	}
 
-	d := distro.New("")
-	for _, format := range d.ListOutputFormats() {
+	for _, format := range api.distro.ListOutputFormats() {
 		reply.Types = append(reply.Types, composeType{format, true})
 	}