Added --show-trace flag to morph

- Put eval-machines path and show trace option in a new struct called NixContext for the purpose of minimising the number of flags we need to pass to nix.GetMachines() and nix.BuildMachines() respectively. - Deprecated the --build-arg flag, because.. it was introduced pretty much only to be able to pass --show-trace, and it only works on "nix build" anyway (not eval) with a lot of existing limitations. fixes #44
DBCDK · Feb 18, 2019 · 29b975d · 29b975d
1 parent feff7d4
commit 29b975d
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Showing 2 changed files with 53 additions and 15 deletions.
diff --git a/morph.go b/morph.go
@@ -42,6 +42,7 @@ var (
 	deployUploadSecrets bool
 	deployReboot        bool
 	skipHealthChecks    bool
+	showTrace			bool
 	healthCheck         = healthCheckCmd(app.Command("check-health", "Run health checks"))
 	uploadSecrets       = uploadSecretsCmd(app.Command("upload-secrets", "Upload secrets"))
 	listSecrets         = listSecretsCmd(app.Command("list-secrets", "List secrets"))
@@ -88,7 +89,7 @@ func selectorFlags(cmd *kingpin.CmdClause) {
 }
 
 func nixBuildArgFlag(cmd *kingpin.CmdClause) {
-	cmd.Flag("build-arg", "Extra argument to pass on to nix-build command.").
+	cmd.Flag("build-arg", "Extra argument to pass on to nix-build command. **DEPRECATED**").
 		StringsVar(&nixBuildArg)
 }
 
@@ -99,6 +100,13 @@ func skipHealthChecksFlag(cmd *kingpin.CmdClause) {
 		BoolVar(&skipHealthChecks)
 }
 
+func showTraceFlag(cmd *kingpin.CmdClause) {
+	cmd.
+		Flag("show-trace", "Whether to pass --show-trace to all nix commands").
+		Default("False").
+		BoolVar(&showTrace)
+}
+
 func asJsonFlag(cmd *kingpin.CmdClause) {
 	cmd.
 		Flag("json", "Whether to format the output as JSON instead of plaintext").
@@ -108,19 +116,22 @@ func asJsonFlag(cmd *kingpin.CmdClause) {
 
 func buildCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 	selectorFlags(cmd)
+	showTraceFlag(cmd)
 	nixBuildArgFlag(cmd)
 	deploymentArg(cmd)
 	return cmd
 }
 
 func pushCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 	selectorFlags(cmd)
+	showTraceFlag(cmd)
 	deploymentArg(cmd)
 	return cmd
 }
 
 func executeCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 	selectorFlags(cmd)
+	showTraceFlag(cmd)
 	askForSudoPasswdFlag(cmd)
 	timeoutFlag(cmd)
 	deploymentArg(cmd)
@@ -134,6 +145,7 @@ func executeCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 
 func deployCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 	selectorFlags(cmd)
+	showTraceFlag(cmd)
 	nixBuildArgFlag(cmd)
 	deploymentArg(cmd)
 	timeoutFlag(cmd)
@@ -157,13 +169,15 @@ func deployCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 
 func healthCheckCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 	selectorFlags(cmd)
+	showTraceFlag(cmd)
 	deploymentArg(cmd)
 	timeoutFlag(cmd)
 	return cmd
 }
 
 func uploadSecretsCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 	selectorFlags(cmd)
+	showTraceFlag(cmd)
 	askForSudoPasswdFlag(cmd)
 	skipHealthChecksFlag(cmd)
 	deploymentArg(cmd)
@@ -172,6 +186,7 @@ func uploadSecretsCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 
 func listSecretsCmd(cmd *kingpin.CmdClause) *kingpin.CmdClause {
 	selectorFlags(cmd)
+	showTraceFlag(cmd)
 	deploymentArg(cmd)
 	asJsonFlag(cmd)
 	return cmd
@@ -196,6 +211,11 @@ func main() {
 
 	clause := kingpin.MustParse(app.Parse(os.Args[1:]))
 
+	//TODO: Remove deprecation warning when removing --build-arg flag
+	if len(nixBuildArg) > 0 {
+		fmt.Fprintln(os.Stderr, "Deprecation: The --build-arg flag will be removed in a future release.")
+	}
+
 	hosts, err := getHosts(deployment)
 	if err != nil {
 		handleError(clause, hosts, err)
@@ -489,14 +509,13 @@ func getHosts(deploymentFile string) (hosts []nix.Host, err error) {
 		return hosts, err
 	}
 
-	evalMachinesPath := filepath.Join(assetRoot, "eval-machines.nix")
-
 	deploymentPath, err := filepath.Abs(deployment.Name())
 	if err != nil {
 		return hosts, err
 	}
 
-	allHosts, err := nix.GetMachines(evalMachinesPath, deploymentPath)
+	ctx := getNixContext()
+	allHosts, err := ctx.GetMachines(deploymentPath)
 	if err != nil {
 		return hosts, err
 	}
@@ -517,9 +536,14 @@ func getHosts(deploymentFile string) (hosts []nix.Host, err error) {
 	return filteredHosts, nil
 }
 
-func buildHosts(hosts []nix.Host) (resultPath string, err error) {
-	evalMachinesPath := filepath.Join(assetRoot, "eval-machines.nix")
+func getNixContext() *nix.NixContext {
+	return &nix.NixContext{
+		EvalMachines: filepath.Join(assetRoot, "eval-machines.nix"),
+		ShowTrace: showTrace,
+	}
+}
 
+func buildHosts(hosts []nix.Host) (resultPath string, err error) {
 	if len(hosts) == 0 {
 		err = errors.New("No hosts selected")
 		return
@@ -530,7 +554,8 @@ func buildHosts(hosts []nix.Host) (resultPath string, err error) {
 		return
 	}
 
-	resultPath, err = nix.BuildMachines(evalMachinesPath, deploymentPath, hosts, nixBuildArg)
+	ctx := getNixContext()
+	resultPath, err = ctx.BuildMachines(deploymentPath, hosts, nixBuildArg)
 	if err != nil {
 		return
 	}

diff --git a/nix/nix.go b/nix/nix.go
@@ -23,6 +23,11 @@ type Host struct {
 	BuildOnly    bool
 }
 
+type NixContext struct {
+	EvalMachines string
+	ShowTrace bool
+}
+
 func (host *Host) GetTargetHost() string {
 	return host.TargetHost
 }
@@ -31,13 +36,18 @@ func (host *Host) GetHealthChecks() healthchecks.HealthChecks {
 	return host.HealthChecks
 }
 
-func GetMachines(evalMachines string, deploymentPath string) (hosts []Host, err error) {
-	cmd := exec.Command(
-		"nix", "eval",
-		"-f", evalMachines, "info.machineList",
+func (ctx *NixContext) GetMachines(deploymentPath string) (hosts []Host, err error) {
+
+	args := []string{"eval",
+		"-f", ctx.EvalMachines, "info.machineList",
 		"--arg", "networkExpr", deploymentPath,
-		"--json",
-	)
+		"--json"}
+
+	if ctx.ShowTrace {
+		args = append(args, "--show-trace")
+	}
+
+	cmd := exec.Command("nix", args...)
 
 	var stdout bytes.Buffer
 	cmd.Stdout = &stdout
@@ -59,7 +69,7 @@ func GetMachines(evalMachines string, deploymentPath string) (hosts []Host, err
 	return hosts, nil
 }
 
-func BuildMachines(evalMachines string, deploymentPath string, hosts []Host, nixArgs []string) (path string, err error) {
+func (ctx *NixContext) BuildMachines(deploymentPath string, hosts []Host, nixArgs []string) (path string, err error) {
 	hostsArg := "["
 	for _, host := range hosts {
 		hostsArg += "\"" + host.TargetHost + "\" "
@@ -75,7 +85,7 @@ func BuildMachines(evalMachines string, deploymentPath string, hosts []Host, nix
 
 	resultLinkPath := filepath.Join(tmpdir, "result")
 
-	args := []string{evalMachines,
+	args := []string{ctx.EvalMachines,
 		"-A", "machines",
 		"--arg", "networkExpr", deploymentPath,
 		"--arg", "names", hostsArg,
@@ -84,6 +94,9 @@ func BuildMachines(evalMachines string, deploymentPath string, hosts []Host, nix
 	if len(nixArgs) > 0 {
 		args = append(args, nixArgs...)
 	}
+	if ctx.ShowTrace {
+		args = append(args, "--show-trace")
+	}
 
 	cmd := exec.Command("nix-build", args...)
 	defer os.Remove(resultLinkPath)