feat(api): add debug route

pkg/gotenberg/debug.go

@@ -1,4 +1,65 @@
 package gotenberg
 
-// Version is the... version of the Gotenberg application.
-var Version = "snapshot"
+import (
+	"runtime"
+	"sync"
+
+	flag "github.com/spf13/pflag"
+)
+
+// DebugInfo gathers data for debugging.
+type DebugInfo struct {
+	Version               string                            `json:"version"`
+	Architecture          string                            `json:"architecture"`
+	Modules               []string                          `json:"modules"`
+	ModulesAdditionalData map[string]map[string]interface{} `json:"modules_additional_data"`
+	Flags                 map[string]interface{}            `json:"flags"`
+}
+
+// BuildDebug builds the debug data from modules.
+func BuildDebug(ctx *Context) {
+	debugMu.Lock()
+	defer debugMu.Unlock()
+
+	debug = &DebugInfo{
+		Version:               Version,
+		Architecture:          runtime.GOARCH,
+		Modules:               make([]string, len(ctx.moduleInstances)),
+		ModulesAdditionalData: make(map[string]map[string]interface{}),
+		Flags:                 make(map[string]interface{}),
+	}
+
+	i := 0
+	for ID, mod := range ctx.moduleInstances {
+		debug.Modules[i] = ID
+		i++
+
+		debuggable, ok := mod.(Debuggable)
+		if !ok {
+			continue
+		}
+
+		debug.ModulesAdditionalData[ID] = debuggable.Debug()
+	}
+
+	ctx.ParsedFlags().VisitAll(func(f *flag.Flag) {
+		debug.Flags[f.Name] = f.Value.String()
+	})
+}
+
+// Debug returns the debug data.
+func Debug() DebugInfo {
+	debugMu.Lock()
+	defer debugMu.Unlock()
+
+	if debug == nil {
+		return DebugInfo{}
+	}
+
+	return *debug
+}
+
+var (
+	debug   *DebugInfo
+	debugMu sync.Mutex
+)