Fix DNS record JSON parsing for MCNS response format

MCNS returns records wrapped in {"records": [...]} envelope with
uppercase field names (ID, Name, Type, Value), not bare arrays
with lowercase fields.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-03-27 15:12:43 -07:00
parent 76247978c2
commit 2bda7fc138
2 changed files with 18 additions and 16 deletions

View File

@@ -28,11 +28,11 @@ type DNSRegistrar struct {
// dnsRecord is the JSON representation of an MCNS record.
type dnsRecord struct {
ID int `json:"id"`
Name string `json:"name"`
Type string `json:"type"`
Value string `json:"value"`
TTL int `json:"ttl"`
ID int `json:"ID"`
Name string `json:"Name"`
Type string `json:"Type"`
Value string `json:"Value"`
TTL int `json:"TTL"`
}
// NewDNSRegistrar creates a DNSRegistrar. Returns (nil, nil) if
@@ -157,11 +157,13 @@ func (d *DNSRegistrar) listRecords(ctx context.Context, serviceName string) ([]d
return nil, fmt.Errorf("list records: mcns returned %d: %s", resp.StatusCode, string(body))
}
var records []dnsRecord
if err := json.Unmarshal(body, &records); err != nil {
var envelope struct {
Records []dnsRecord `json:"records"`
}
if err := json.Unmarshal(body, &envelope); err != nil {
return nil, fmt.Errorf("parse list response: %w", err)
}
return records, nil
return envelope.Records, nil
}
// createRecord creates an A record in the zone.

View File

@@ -39,7 +39,7 @@ func TestEnsureRecordCreatesWhenMissing(t *testing.T) {
if r.Method == http.MethodGet {
// List returns empty — no existing records.
w.Header().Set("Content-Type", "application/json")
_, _ = w.Write([]byte("[]"))
_, _ = w.Write([]byte(`{"records":[]}`))
return
}
gotMethod = r.Method
@@ -90,9 +90,9 @@ func TestEnsureRecordSkipsWhenExists(t *testing.T) {
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if r.Method == http.MethodGet {
// Return an existing record with the correct value.
records := []dnsRecord{{ID: 1, Name: "myservice", Type: "A", Value: "192.168.88.181", TTL: 300}}
resp := map[string][]dnsRecord{"records": {{ID: 1, Name: "myservice", Type: "A", Value: "192.168.88.181", TTL: 300}}}
w.Header().Set("Content-Type", "application/json")
_ = json.NewEncoder(w).Encode(records)
_ = json.NewEncoder(w).Encode(resp)
return
}
createCalled = true
@@ -124,9 +124,9 @@ func TestEnsureRecordUpdatesWrongValue(t *testing.T) {
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if r.Method == http.MethodGet {
// Return a record with a stale value.
records := []dnsRecord{{ID: 42, Name: "myservice", Type: "A", Value: "10.0.0.1", TTL: 300}}
resp := map[string][]dnsRecord{"records": {{ID: 42, Name: "myservice", Type: "A", Value: "10.0.0.1", TTL: 300}}}
w.Header().Set("Content-Type", "application/json")
_ = json.NewEncoder(w).Encode(records)
_ = json.NewEncoder(w).Encode(resp)
return
}
gotMethod = r.Method
@@ -160,9 +160,9 @@ func TestRemoveRecordDeletes(t *testing.T) {
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if r.Method == http.MethodGet {
records := []dnsRecord{{ID: 7, Name: "myservice", Type: "A", Value: "192.168.88.181", TTL: 300}}
resp := map[string][]dnsRecord{"records": {{ID: 7, Name: "myservice", Type: "A", Value: "192.168.88.181", TTL: 300}}}
w.Header().Set("Content-Type", "application/json")
_ = json.NewEncoder(w).Encode(records)
_ = json.NewEncoder(w).Encode(resp)
return
}
gotMethod = r.Method
@@ -195,7 +195,7 @@ func TestRemoveRecordNoopWhenMissing(t *testing.T) {
srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
// List returns empty.
w.Header().Set("Content-Type", "application/json")
_, _ = w.Write([]byte("[]"))
_, _ = w.Write([]byte(`{"records":[]}`))
}))
defer srv.Close()