[+] add tests for "pgwatch metric print" commands

Author: pashagolub

internal/cmdopts/cmdmetric.go

@@ -36,6 +36,7 @@ func (cmd *MetricPrintInitCommand) Execute(args []string) error {
 	if err != nil {
 		return err
 	}
+	w := cmd.owner.OutputWriter
 	for _, name := range args {
 		if preset, ok := metrics.PresetDefs[name]; ok {
 			args = append(args, maps.Keys(preset.Metrics)...)
@@ -45,8 +46,9 @@ func (cmd *MetricPrintInitCommand) Execute(args []string) error {
 	args = slices.Compact(args)
 	for _, mname := range args {
 		if m, ok := metrics.MetricDefs[mname]; ok && m.InitSQL != "" {
-			fmt.Println("-- ", mname)
-			fmt.Println(m.InitSQL)
+
+			fmt.Fprintln(w, "--", mname)
+			fmt.Fprintln(w, m.InitSQL)
 		}
 	}
 	cmd.owner.CompleteCommand(ExitCodeOK)
@@ -67,13 +69,15 @@ func (cmd *MetricPrintSQLCommand) Execute(args []string) error {
 	if err != nil {
 		return err
 	}
+	w := cmd.owner.OutputWriter
 	if cmd.Version == 0 {
 		cmd.Version = math.MaxInt32
 	}
 	for _, name := range args {
 		if m, ok := metrics.MetricDefs[name]; ok {
-			fmt.Println("-- ", name)
-			fmt.Println(m.GetSQL(cmd.Version))
+			if v := m.GetSQL(cmd.Version); v > "" {
+				fmt.Fprintln(w, "--", name, v)
+			}
 		}
 	}
 	cmd.owner.CompleteCommand(ExitCodeOK)

internal/cmdopts/cmdmetric_test.go

@@ -0,0 +1,70 @@
+package cmdopts
+
+import (
+	"os"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMetricPrintInit_Execute(t *testing.T) {
+
+	var err error
+
+	w := &strings.Builder{}
+	os.Args = []string{0: "config_test", "metric", "print-init", "test1"}
+	_, err = New(w)
+	assert.Empty(t, w.String())
+	assert.NoError(t, err, "should not error when no metrics found")
+
+	w.Reset()
+	os.Args = []string{0: "config_test", "metric", "print-init", "cpu_load"}
+	_, err = New(w)
+	assert.Contains(t, w.String(), "-- cpu_load")
+	assert.NoError(t, err)
+
+	w.Reset()
+	os.Args = []string{0: "config_test", "metric", "print-init", "standard"}
+	_, err = New(w)
+	assert.Contains(t, w.String(), "-- cpu_load")
+	assert.NoError(t, err)
+
+	os.Args = []string{0: "config_test", "--metrics=foo", "metric", "print-init", "standard"}
+	_, err = New(w)
+	assert.Error(t, err, "should error when no metric definitions found")
+
+	os.Args = []string{0: "config_test", "--metrics=postgresql://foo@bar/fail", "metric", "print-init", "standard"}
+	_, err = New(w)
+	assert.Error(t, err, "should error when no config database found")
+}
+
+func TestMetricPrintSQL_Execute(t *testing.T) {
+	var err error
+
+	w := &strings.Builder{}
+	os.Args = []string{0: "config_test", "metric", "print-sql", "test1"}
+	_, err = New(w)
+	assert.Empty(t, w.String())
+	assert.NoError(t, err, "should not error when no metrics found")
+
+	w.Reset()
+	os.Args = []string{0: "config_test", "metric", "print-sql", "cpu_load"}
+	_, err = New(w)
+	assert.Contains(t, w.String(), "get_load_average()")
+	assert.NoError(t, err)
+
+	w.Reset()
+	os.Args = []string{0: "config_test", "metric", "print-sql", "cpu_load", "--version=10"}
+	_, err = New(w)
+	assert.Empty(t, w.String(), "should not print anything for deprecated version")
+	assert.NoError(t, err)
+
+	os.Args = []string{0: "config_test", "--metrics=foo", "metric", "print-sql", "foo"}
+	_, err = New(w)
+	assert.Error(t, err, "should error when no metric definitions found")
+
+	os.Args = []string{0: "config_test", "--metrics=postgresql://foo@bar/fail", "metric", "print-sql", "foo"}
+	_, err = New(w)
+	assert.Error(t, err, "should error when no config database found")
+}

internal/cmdopts/cmdoptions.go

@@ -52,6 +52,8 @@ type Options struct {
 
 	ExitCode         int32
 	CommandCompleted bool
+
+	OutputWriter io.Writer
 }
 
 func addCommands(parser *flags.Parser, opts *Options) {
@@ -69,6 +71,7 @@ func New(writer io.Writer) (cmdOpts *Options, err error) {
 	cmdOpts = new(Options)
 	parser := flags.NewParser(cmdOpts, flags.HelpFlag)
 	parser.SubcommandsOptional = true // if not command specified, start monitoring
+	cmdOpts.OutputWriter = writer
 	addCommands(parser, cmdOpts)
 	nonParsedArgs, err := parser.Parse() // parse and execute subcommand if any
 	if err != nil {