Refactor BaseConf Read and Parse

Also refactor New and Get to return pointers to match BaseConf methods.
This makes calling the methods immediately on the return values of the
constructors easier.

Also move config.ConfigFile to buildconfig.go.in. ConfigFile is still
used by wwctl as a default config file to reference; but it is removed
from other locations now.

Removed Persist, as nothing called it.

Signed-off-by: Jonathon Anderson <janderson@ciq.co>

Makefile

@@ -151,7 +151,7 @@ vet:
 	go vet ./...
 
 test-it:
-	go test -v ./... -ldflags="-X 'github.com/hpcng/warewulf/internal/pkg/config.ConfigFile=$(shell pwd)/etc/warewulf.conf'"
+	go test -v ./...
 
 # Generate test coverage
 test-cover:     ## Run test coverage and generate html report
@@ -219,13 +219,12 @@ init:
 wwctl: $(WWCTL_DEPS)
 	@echo Building "$@"
 	@cd cmd/wwctl; GOOS=linux go build -mod vendor -tags "$(WW_GO_BUILD_TAGS)" \
-	-ldflags "-X 'github.com/hpcng/warewulf/internal/pkg/config.ConfigFile=$(SYSCONFDIR)/warewulf/warewulf.conf'" \
 	-o ../../wwctl
 
 wwclient: $(WWCLIENT_DEPS)
 	@echo Building "$@"
-	@cd cmd/wwclient; CGO_ENABLED=0 GOOS=linux go build -mod vendor -a -ldflags "-extldflags -static \
-	 -X 'github.com/hpcng/warewulf/internal/pkg/config.ConfigFile=/etc/warewulf/warewulf.conf'" -o ../../wwclient
+	@cd cmd/wwclient; CGO_ENABLED=0 GOOS=linux go build -mod vendor -a -ldflags "-extldflags -static" \
+	-o ../../wwclient
 
 man_pages: wwctl
 	@install -d man_pages
@@ -235,7 +234,7 @@ man_pages: wwctl
 	@cd man_pages; for i in wwctl*1 *.5; do gzip --force $$i; echo -n "$$i "; done; echo
 
 update_configuration: vendor cmd/update_configuration/update_configuration.go
-	cd cmd/update_configuration && go build -ldflags="-X 'github.com/hpcng/warewulf/internal/pkg/config.ConfigFile=./etc/warewulf.conf'\
+	cd cmd/update_configuration && go build \
 	 -X 'github.com/hpcng/warewulf/internal/pkg/node.ConfigFile=./etc/nodes.conf'"\
 	 -mod vendor -tags "$(WW_GO_BUILD_TAGS)" -o ../../update_configuration
 

internal/app/wwctl/container/list/main_test.go

@@ -56,7 +56,7 @@ WW_INTERNAL: 0
     `
 
 	conf := warewulfconf.Get()
-	err := conf.Read([]byte(conf_yml))
+	err := conf.Parse([]byte(conf_yml))
 	assert.NoError(t, err)
 	warewulfd.SetNoDaemon()
 	for _, tt := range tests {

internal/app/wwctl/node/add/main_test.go

@@ -243,7 +243,7 @@ nodes:
 	_, warewulfConfErr = tempWarewulfConf.Write([]byte(conf_yml))
 	assert.NoError(t, warewulfConfErr)
 	assert.NoError(t, tempWarewulfConf.Sync())
-	warewulfconf.ConfigFile = tempWarewulfConf.Name()
+	warewulfconf.New().Read(tempWarewulfConf.Name())
 
 	nodes_yml := `WW_INTERNAL: 43`
 	tempNodeConf, nodesConfErr := os.CreateTemp("", "nodes.conf-")

internal/app/wwctl/node/list/main_test.go

@@ -42,7 +42,7 @@ nodes:
 	_, warewulfConfErr = tempWarewulfConf.Write([]byte(conf_yml))
 	assert.NoError(t, warewulfConfErr)
 	assert.NoError(t, tempWarewulfConf.Sync())
-	warewulfconf.ConfigFile = tempWarewulfConf.Name()
+	warewulfconf.New().Read(tempWarewulfConf.Name())
 
 	tempNodeConf, nodesConfErr := os.CreateTemp("", "nodes.conf-")
 	assert.NoError(t, nodesConfErr)

internal/app/wwctl/profile/list/main_test.go

@@ -43,7 +43,7 @@ nodes:
 	_, warewulfConfErr = tempWarewulfConf.Write([]byte(conf_yml))
 	assert.NoError(t, warewulfConfErr)
 	assert.NoError(t, tempWarewulfConf.Sync())
-	warewulfconf.ConfigFile = tempWarewulfConf.Name()
+	warewulfconf.New().Read(tempWarewulfConf.Name())
 
 	tempNodeConf, nodesConfErr := os.CreateTemp("", "nodes.conf-")
 	assert.NoError(t, nodesConfErr)

internal/app/wwctl/root.go

@@ -79,11 +79,11 @@ func rootPersistentPreRunE(cmd *cobra.Command, args []string) (err error) {
 	conf := warewulfconf.Get()
 	if !AllowEmptyConf && !conf.InitializedFromFile() {
 		if WarewulfConfArg != "" {
-			err = conf.ReadConf(WarewulfConfArg)
+			err = conf.Read(WarewulfConfArg)
 		} else if os.Getenv("WAREWULFCONF") != "" {
-			err = conf.ReadConf(os.Getenv("WAREWULFCONF"))
+			err = conf.Read(os.Getenv("WAREWULFCONF"))
 		} else {
-			err = conf.ReadConf(warewulfconf.ConfigFile)
+			err = conf.Read(warewulfconf.ConfigFile)
 		}
 	} else {
 		err = conf.SetDynamicDefaults()

internal/pkg/config/buildconfig.go.in

@@ -1,5 +1,7 @@
 package config
 
+var ConfigFile = "@SYSCONFDIR@/warewulf/warewulf.conf"
+
 type BuildConfig struct {
 	Bindir         string `default:"@BINDIR@"`
 	Sysconfdir     string `default:"@SYSCONFDIR@"`

internal/pkg/config/root.go

@@ -21,10 +21,7 @@ import (
 )
 
 
-var (
-	cachedConf RootConf
-	ConfigFile string
-)
+var cachedConf RootConf
 
 
 // RootConf is the main Warewulf configuration structure. It stores
@@ -50,65 +47,67 @@ type RootConf struct {
 }
 
 
-// New returns a [RootConf] initialized with empty values.
-func New() (conf RootConf) {
-	conf.Warewulf = new(WarewulfConf)
-	conf.Dhcp = new(DhcpConf)
-	conf.Tftp = new(TftpConf)
-	conf.Nfs = new(NfsConf)
-	conf.Paths = new(BuildConfig)
-	_ = defaults.Set(&conf)
-	return
+// New caches and returns a new [RootConf] initialized with empty
+// values, clearing replacing any previously cached value.
+func New() (*RootConf) {
+	cachedConf = RootConf{}
+	cachedConf.fromFile = false
+	cachedConf.Warewulf = new(WarewulfConf)
+	cachedConf.Dhcp = new(DhcpConf)
+	cachedConf.Tftp = new(TftpConf)
+	cachedConf.Nfs = new(NfsConf)
+	cachedConf.Paths = new(BuildConfig)
+	if err := defaults.Set(&cachedConf); err != nil {
+		panic(err)
+	}
+	return &cachedConf
 }
 
 
-// Get returns a [RootConf] which may have been cached from a previous
-// call.
-func Get() (RootConf) {
+// Get returns a previously cached [RootConf] if it exists, or returns
+// a new RootConf.
+func Get() (*RootConf) {
 	// NOTE: This function can be called before any log level is set
 	//       so using wwlog.Verbose or wwlog.Debug won't work
 	if reflect.ValueOf(cachedConf).IsZero() {
-		cachedConf = New()
-		cachedConf.fromFile = false
+		cachedConf = *New()
 	}
-	return cachedConf
+	return &cachedConf
 }
 
 
 // ReadConf populates [RootConf] with the values from a configuration
 // file.
-func (conf *RootConf) ReadConf(confFileName string) (err error) {
+func (conf *RootConf) Read(confFileName string) (error) {
 	wwlog.Debug("Reading warewulf.conf from: %s", confFileName)
-	fileHandle, err := os.ReadFile(confFileName)
+	data, err := os.ReadFile(confFileName)
 	if err != nil {
 		return err
 	}
-	return conf.Read(fileHandle)
+	return conf.Parse(data)
 }
 
 
 // Read populates [RootConf] with the values from a yaml document.
-func (conf *RootConf) Read(data []byte) (err error) {
+func (conf *RootConf) Parse(data []byte) (error) {
 	// ipxe binaries are merged not overwritten, store defaults separate
 	defIpxe := make(map[string]string)
 	for k, v := range conf.Tftp.IpxeBinaries {
 		defIpxe[k] = v
 		delete(conf.Tftp.IpxeBinaries, k)
 	}
-	err = yaml.Unmarshal(data, &conf)
-	if err != nil {
-		return
+	if err := yaml.Unmarshal(data, &conf); err != nil {
+		return err
 	}
-	err = conf.SetDynamicDefaults()
-	if err != nil {
-		return
+	if err := conf.SetDynamicDefaults(); err != nil {
+		return err
 	}
 	if len(conf.Tftp.IpxeBinaries) == 0 {
 		conf.Tftp.IpxeBinaries = defIpxe
 	}
 	cachedConf = *conf
 	cachedConf.fromFile = true
-	return
+	return nil
 }
 
 
@@ -185,29 +184,3 @@ func (conf *RootConf) SetDynamicDefaults() (err error) {
 func (conf *RootConf) InitializedFromFile() bool {
 	return conf.fromFile
 }
-
-
-// Persist writes [RootConf] to a file as a yaml document.
-func (controller *RootConf) Persist() error {
-
-	out, err := yaml.Marshal(controller)
-	if err != nil {
-		return err
-	}
-
-	file, err := os.OpenFile(ConfigFile, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0644)
-	if err != nil {
-		wwlog.Error("%s", err)
-		os.Exit(1)
-	}
-
-	defer file.Close()
-
-	_, err = file.WriteString(string(out)+"\n")
-	if err != nil {
-		wwlog.Error("Unable to write to warewulf.conf")
-		return err
-	}
-
-	return nil
-}