From a1f0bcbafe86d84d306ad4f3a241c0a582a7651f Mon Sep 17 00:00:00 2001
From: MacRat <m@crat.jp>
Date: Sun, 20 Nov 2022 00:07:21 +0900
Subject: [PATCH] fix(lib): avoid to print invalid JSON even if target is nil

---
 lib-ayd/record.go      | 7 ++++++-
 lib-ayd/record_test.go | 4 ++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/lib-ayd/record.go b/lib-ayd/record.go
index 6de0bb65..aa843825 100644
--- a/lib-ayd/record.go
+++ b/lib-ayd/record.go
@@ -180,13 +180,18 @@ func (r *Record) UnmarshalJSON(data []byte) error {
 func (r Record) MarshalJSON() ([]byte, error) {
 	head := bytes.NewBuffer(make([]byte, 0, 256))
 
+	target := ""
+	if r.Target != nil {
+		target = r.Target.String()
+	}
+
 	_, err := fmt.Fprintf(
 		head,
 		`{"time":"%s", "status":"%s", "latency":%.3f, "target":%q`,
 		r.Time.Format(time.RFC3339),
 		r.Status,
 		float64(r.Latency.Microseconds())/1000,
-		r.Target,
+		target,
 	)
 	if err != nil {
 		return nil, err
diff --git a/lib-ayd/record_test.go b/lib-ayd/record_test.go
index c406e27e..8f0c9423 100644
--- a/lib-ayd/record_test.go
+++ b/lib-ayd/record_test.go
@@ -377,6 +377,10 @@ func TestRecord_MarshalJSON(t *testing.T) {
 			},
 			`{"time":"2021-01-02T15:04:05Z", "status":"HEALTHY", "latency":0.000, "target":"dummy:", "foo":"bar"}`,
 		},
+		{
+			ayd.Record{},
+			`{"time":"0001-01-01T00:00:00Z", "status":"UNKNOWN", "latency":0.000, "target":""}`,
+		},
 	}
 
 	for i, tt := range tests {