From 5432360f0e5ecb4368a946d84e54826afc5aa90c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emmanuel=20BENO=C3=8ET?= <tseeker@nocternity.net>
Date: Fri, 19 Jul 2024 23:46:33 +0200
Subject: [PATCH] refactor(pkg): refactor `Plugin` to make it easier to test

Writing the plugin's output string and exiting the program will no
longer take place in the plugin status itself. It will only be done in
the main program.
---
 cmd/sslcert/main.go    |  6 +++---
 cmd/zoneserial/main.go | 10 +++-------
 main.go                | 13 ++++++++++++-
 pkg/plugin/plugin.go   | 16 +++++++++-------
 pkg/program/program.go |  4 +++-
 5 files changed, 30 insertions(+), 19 deletions(-)

diff --git a/cmd/sslcert/main.go b/cmd/sslcert/main.go
index efb4971..be9c921 100644
--- a/cmd/sslcert/main.go
+++ b/cmd/sslcert/main.go
@@ -215,9 +215,9 @@ func NewProgram() program.Program {
 	return program
 }
 
-// Terminate the monitoring check program.
-func (program *checkProgram) Done() {
-	program.plugin.Done()
+// Return the program's output value.
+func (program *checkProgram) Output() *plugin.Plugin {
+	return program.plugin
 }
 
 // Check the values that were specified from the command line. Returns true
diff --git a/cmd/zoneserial/main.go b/cmd/zoneserial/main.go
index e8bc7d6..69bd27d 100644
--- a/cmd/zoneserial/main.go
+++ b/cmd/zoneserial/main.go
@@ -85,13 +85,9 @@ func NewProgram() program.Program {
 	return program
 }
 
-// Terminate the monitoring check program.
-func (program *checkProgram) Done() {
-	if r := recover(); r != nil {
-		program.plugin.SetState(plugin.StatusUnknown, "Internal error")
-		program.plugin.AddLinef("Error info: %v", r)
-	}
-	program.plugin.Done()
+// Return the program's output value.
+func (program *checkProgram) Output() *plugin.Plugin {
+	return program.plugin
 }
 
 // Check the values that were specified from the command line. Returns true if the arguments made sense.
diff --git a/main.go b/main.go
index e8ce79a..af989b1 100644
--- a/main.go
+++ b/main.go
@@ -7,6 +7,7 @@ import (
 
 	"nocternity.net/gomonop/cmd/sslcert"
 	"nocternity.net/gomonop/cmd/zoneserial"
+	"nocternity.net/gomonop/pkg/plugin"
 	"nocternity.net/gomonop/pkg/program"
 	"nocternity.net/gomonop/pkg/version"
 )
@@ -55,7 +56,17 @@ func getProgram() program.Program {
 
 func main() {
 	program := getProgram()
-	defer program.Done()
+
+	output := program.Output()
+	defer func() {
+		if r := recover(); r != nil {
+			output.SetState(plugin.StatusUnknown, "Internal error")
+			output.AddLinef("Error info: %v", r)
+		}
+		fmt.Println(output.String())
+		os.Exit(output.ExitCode())
+	}()
+
 	if program.CheckArguments() {
 		program.RunCheck()
 	}
diff --git a/pkg/plugin/plugin.go b/pkg/plugin/plugin.go
index 061b06f..b967e9f 100644
--- a/pkg/plugin/plugin.go
+++ b/pkg/plugin/plugin.go
@@ -5,7 +5,6 @@ package plugin // import nocternity.net/gomonop/pkg/perfdata
 import (
 	"container/list"
 	"fmt"
-	"os"
 	"strings"
 
 	"nocternity.net/gomonop/pkg/perfdata"
@@ -70,10 +69,9 @@ func (p *Plugin) AddPerfData(pd *perfdata.PerfData) {
 	p.perfData[pd.Label] = pd
 }
 
-// Done generates the plugin's text output from its name, status, text data
-// and performance data, before exiting with the code corresponding to the
-// status.
-func (p *Plugin) Done() {
+// String generates the plugin's text output from its name, status, text data
+// and performance data.
+func (p *Plugin) String() string {
 	var strBuilder strings.Builder
 	strBuilder.WriteString(p.name)
 	strBuilder.WriteString(" ")
@@ -99,6 +97,10 @@ func (p *Plugin) Done() {
 			strBuilder.WriteString(em.Value.(string))
 		}
 	}
-	fmt.Println(strBuilder.String())
-	os.Exit(int(p.status))
+	return strBuilder.String()
+}
+
+// ExitCode returns the plugin's exit code.
+func (p *Plugin) ExitCode() int {
+	return int(p.status)
 }
diff --git a/pkg/program/program.go b/pkg/program/program.go
index d8b3510..2d5a1dd 100644
--- a/pkg/program/program.go
+++ b/pkg/program/program.go
@@ -1,9 +1,11 @@
 package program // import nocternity.net/gomonop/pkg/program
 
+import "nocternity.net/gomonop/pkg/plugin"
+
 type Program interface {
+	Output() *plugin.Plugin
 	CheckArguments() bool
 	RunCheck()
-	Done()
 }
 
 type Builder func() Program