[gfrankliu]

ngx_http_upsync_consul_health_parse_json() reads checks->child without checking that cJSON_GetObjectItem(server_next, "Checks") returned non-NULL. A /v1/health/service/<name> entry without a Checks array crashes the worker (SIGSEGV). This has been there since consul_health was added in #183.

The fix skips only the health check loop when Checks is missing, so the server is kept and its weight=/max_fails=/fail_timeout=/down/backup tags are still applied.

Tested with an AddressSanitizer build against nginx 1.26.3 and a mock Consul health endpoint returning three entries (all checks passing; one check critical; no Checks but a weight=5 tag):

• before: SEGV ... ngx_http_upsync_module.c:1698 in ngx_http_upsync_consul_health_parse_json
• after:

server 10.0.0.3:9003 weight=5 max_fails=2 fail_timeout=10s;
server 10.0.0.22:9002 weight=1 max_fails=2 fail_timeout=10s down;
server 10.0.0.1:9001 weight=3 max_fails=2 fail_timeout=10s;