chore: make healthcheck output concise

[7-zete-7]

The current healthcheck generates large output.

Example of the current healthcheck output.

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  9724    0  9724    0     0  5302k      0 --:--:-- --:--:-- --:--:-- 9496k
# HELP caddy_admin_http_requests_total Counter of requests made to the Admin API's HTTP endpoints.
# TYPE caddy_admin_http_requests_total counter
caddy_admin_http_requests_total{code="200",handler="admin",method="GET",path="/metrics"} 2
# HELP caddy_config_last_reload_success_timestamp_seconds Timestamp of the last successful configuration reload.
# TYPE caddy_config_last_reload_success_timestamp_seconds gauge
caddy_config_last_reload_success_timestamp_seconds 1.7605256891274564e+09
# HELP caddy_config_last_reload_successful Whether the last configuration reload attempt was successful.
# TYPE caddy_config_last_reload_successful gauge
caddy_config_last_reload_successful 1
# HELP go_build_info Build information about the main Go module.
# TYPE go_build_info gauge
go_build_info{checksum="",path="github.com/dunglas/frankenphp/caddy",version="(devel)"} 1
# HELP go_gc_duration_seconds A summary of the wall-time pause (stop-the-world) duration in garbage collection cycles.
# TYPE go_gc_duration_seconds summary
go_gc_duration_seconds{quantile="0"} 1.9832e-05
go_gc_duration_seconds{quantile="0.25"} 3.756e-05
go_gc_duration_seconds{quantile="0.5"} 0.000111805
go_gc_duration_seconds{quantile="0.75"} 0.000243208
go_gc_duration_seconds{quantile="1"} 0.000390018
go_gc_duration_seconds_sum 0.001436871
go_gc_duration_seconds_count 9
# HELP go_gc_gogc_percent Heap size target percentage configured by the user, otherwise 100. This value is set by the GOGC environment variable, and the runtime/debug.SetGCPercent function. Sourced from /gc/gogc:percent.
# TYPE go_gc_gogc_percent gauge
go_gc_gogc_percent 100
# HELP go_gc_gomemlimit_bytes Go runtime memory limit configured by the user, otherwise math.MaxInt64. This value is set by the GOMEMLIMIT environment variable, and the runtime/debug.SetMemoryLimit function. Sourced from /gc/gomemlimit:bytes.
# TYPE go_gc_gomemlimit_bytes gauge
go_gc_gomemlimit_bytes 1.1289924403e+10
# HELP go_goroutines Number of goroutines that currently exist.
# TYPE go_goroutines gauge
go_goroutines 31
# HELP go_info Information about the Go environment.
# TYPE go_info gauge
go_info{version="go1.25.1"} 1
# HELP go_memstats_alloc_bytes Number of bytes allocated in heap and currently in use. Equals to /memory/classes/heap/objects:bytes.
# TYPE go_memstats_alloc_bytes gauge
go_memstats_alloc_bytes 6.196992e+06
# HELP go_memstats_alloc_bytes_total Total number of bytes allocated in heap until now, even if released already. Equals to /gc/heap/allocs:bytes.
# TYPE go_memstats_alloc_bytes_total counter
go_memstats_alloc_bytes_total 2.4296032e+07
# HELP go_memstats_buck_hash_sys_bytes Number of bytes used by the profiling bucket hash table. Equals to /memory/classes/profiling/buckets:bytes.
# TYPE go_memstats_buck_hash_sys_bytes gauge
go_memstats_buck_hash_sys_bytes 1.460757e+06
# HELP go_memstats_frees_total Total number of heap objects frees. Equals to /gc/heap/frees:objects + /gc/heap/tiny/allocs:objects.
# TYPE go_memstats_frees_total counter
go_memstats_frees_total 254176
# HELP go_memstats_gc_sys_bytes Number of bytes used for garbage collection system metadata. Equals to /memory/classes/metadata/other:bytes.
# TYPE go_memstats_gc_sys_bytes gauge
go_memstats_gc_sys_bytes 3.790096e+06
# HELP go_memstats_heap_alloc_bytes Number of heap bytes allocated and currently in use, same as go_memstats_alloc_bytes. Equals to /memory/classes/heap/objects:bytes.
# TYPE go_memstats_heap_alloc_bytes gauge
go_memstats_heap_alloc_bytes 6.196992e+06
# HELP go_memstats_heap_idle_bytes Number of heap bytes waiting to be used. Equals to /memory/classes/heap/released:bytes + /memory/classes/heap/free:bytes.
# TYPE go_memstats_heap_idle_bytes gauge
go_memstats_heap_idle_bytes 2.809856e+06
# HELP go_memstats_heap_inuse_bytes Number of heap bytes that are in use. Equals to /memory/classes/heap/objects:bytes + /memory/classes/heap/unused:bytes
# TYPE go_memstats_heap_inuse_bytes gauge
go_memstats_heap_inuse_bytes 8.757248e+06
# HELP go_memstats_heap_objects Number of currently allocated objects. Equals to /gc/heap/objects:objects.
# TYPE go_memstats_heap_objects gauge
go_memstats_heap_objects 55519
# HELP go_memstats_heap_released_bytes Number of heap bytes released to OS. Equals to /memory/classes/heap/released:bytes.
# TYPE go_memstats_heap_released_bytes gauge
go_memstats_heap_released_bytes 2.113536e+06
# HELP go_memstats_heap_sys_bytes Number of heap bytes obtained from system. Equals to /memory/classes/heap/objects:bytes + /memory/classes/heap/unused:bytes + /memory/classes/heap/released:bytes + /memory/classes/heap/free:bytes.
# TYPE go_memstats_heap_sys_bytes gauge
go_memstats_heap_sys_bytes 1.1567104e+07
# HELP go_memstats_last_gc_time_seconds Number of seconds since 1970 of last garbage collection.
# TYPE go_memstats_last_gc_time_seconds gauge
go_memstats_last_gc_time_seconds 1.7605257151296017e+09
# HELP go_memstats_mallocs_total Total number of heap objects allocated, both live and gc-ed. Semantically a counter version for go_memstats_heap_objects gauge. Equals to /gc/heap/allocs:objects + /gc/heap/tiny/allocs:objects.
# TYPE go_memstats_mallocs_total counter
go_memstats_mallocs_total 309695
# HELP go_memstats_mcache_inuse_bytes Number of bytes in use by mcache structures. Equals to /memory/classes/metadata/mcache/inuse:bytes.
# TYPE go_memstats_mcache_inuse_bytes gauge
go_memstats_mcache_inuse_bytes 4832
# HELP go_memstats_mcache_sys_bytes Number of bytes used for mcache structures obtained from system. Equals to /memory/classes/metadata/mcache/inuse:bytes + /memory/classes/metadata/mcache/free:bytes.
# TYPE go_memstats_mcache_sys_bytes gauge
go_memstats_mcache_sys_bytes 15704
# HELP go_memstats_mspan_inuse_bytes Number of bytes in use by mspan structures. Equals to /memory/classes/metadata/mspan/inuse:bytes.
# TYPE go_memstats_mspan_inuse_bytes gauge
go_memstats_mspan_inuse_bytes 160800
# HELP go_memstats_mspan_sys_bytes Number of bytes used for mspan structures obtained from system. Equals to /memory/classes/metadata/mspan/inuse:bytes + /memory/classes/metadata/mspan/free:bytes.
# TYPE go_memstats_mspan_sys_bytes gauge
go_memstats_mspan_sys_bytes 195840
# HELP go_memstats_next_gc_bytes Number of heap bytes when next garbage collection will take place. Equals to /gc/heap/goal:bytes.
# TYPE go_memstats_next_gc_bytes gauge
go_memstats_next_gc_bytes 8.485354e+06
# HELP go_memstats_other_sys_bytes Number of bytes used for other system allocations. Equals to /memory/classes/other:bytes.
# TYPE go_memstats_other_sys_bytes gauge
go_memstats_other_sys_bytes 1.179531e+06
# HELP go_memstats_stack_inuse_bytes Number of bytes obtained from system for stack allocator in non-CGO environments. Equals to /memory/classes/heap/stacks:bytes.
# TYPE go_memstats_stack_inuse_bytes gauge
go_memstats_stack_inuse_bytes 1.015808e+06
# HELP go_memstats_stack_sys_bytes Number of bytes obtained from system for stack allocator. Equals to /memory/classes/heap/stacks:bytes + /memory/classes/os-stacks:bytes.
# TYPE go_memstats_stack_sys_bytes gauge
go_memstats_stack_sys_bytes 1.015808e+06
# HELP go_memstats_sys_bytes Number of bytes obtained from system. Equals to /memory/classes/total:byte.
# TYPE go_memstats_sys_bytes gauge
go_memstats_sys_bytes 1.922484e+07
# HELP go_sched_gomaxprocs_threads The current runtime.GOMAXPROCS setting, or the number of operating system threads that can execute user-level Go code simultaneously. Sourced from /sched/gomaxprocs:threads.
# TYPE go_sched_gomaxprocs_threads gauge
go_sched_gomaxprocs_threads 4
# HELP go_threads Number of OS threads created.
# TYPE go_threads gauge
go_threads 20
# HELP mercure_subscribers_connected The current number of running subscribers
# TYPE mercure_subscribers_connected gauge
mercure_subscribers_connected 0
# HELP mercure_subscribers_total Total number of handled subscribers
# TYPE mercure_subscribers_total counter
mercure_subscribers_total 0
# HELP mercure_updates_total Total number of handled updates
# TYPE mercure_updates_total counter
mercure_updates_total 0
# HELP process_cpu_seconds_total Total user and system CPU time spent in seconds.
# TYPE process_cpu_seconds_total counter
process_cpu_seconds_total 0.18
# HELP process_max_fds Maximum number of open file descriptors.
# TYPE process_max_fds gauge
process_max_fds 1.048576e+06
# HELP process_network_receive_bytes_total Number of bytes received by the process over the network.
# TYPE process_network_receive_bytes_total counter
process_network_receive_bytes_total 29791
# HELP process_network_transmit_bytes_total Number of bytes sent by the process over the network.
# TYPE process_network_transmit_bytes_total counter
process_network_transmit_bytes_total 31429
# HELP process_open_fds Number of open file descriptors.
# TYPE process_open_fds gauge
process_open_fds 13
# HELP process_resident_memory_bytes Resident memory size in bytes.
# TYPE process_resident_memory_bytes gauge
process_resident_memory_bytes 9.0263552e+07
# HELP process_start_time_seconds Start time of the process since unix epoch in seconds.
# TYPE process_start_time_seconds gauge
process_start_time_seconds 1.76052568819e+09
# HELP process_virtual_memory_bytes Virtual memory size in bytes.
# TYPE process_virtual_memory_bytes gauge
process_virtual_memory_bytes 3.0848e+09
# HELP process_virtual_memory_max_bytes Maximum amount of virtual memory available in bytes.
# TYPE process_virtual_memory_max_bytes gauge
process_virtual_memory_max_bytes 1.8446744073709552e+19
# HELP promhttp_metric_handler_requests_in_flight Current number of scrapes being served.
# TYPE promhttp_metric_handler_requests_in_flight gauge
promhttp_metric_handler_requests_in_flight 1
# HELP promhttp_metric_handler_requests_total Total number of scrapes by HTTP status code.
# TYPE promhttp_metric_handler_requests_total counter
promhttp_metric_handler_requests_total{code="200"} 2
promhttp_metric_handler_requests_total{code="500"} 0
promhttp_metric_handler_requests_total{code="503"} 0

This PR proposes disabling output and the progress bar, displaying only error messages, if any.

Added options:

• -s, --silent — disables the progress bar and additional informational messages
• -S, --show-error — enables display of error messages, if any
• -o, --output /dev/null — prevents response output

Example of healthcheck with new parameters

$ curl -sSfo /dev/null http://localhost:2019/metrics; echo "Exit code is $?"
Exit code is 0

$ curl -sSfo /dev/null http://localhost:2019/does-not-exists; echo "Exit code is $?"
curl: (22) The requested URL returned error: 404
Exit code is 22

$ curl -sSfo /dev/null https://localhost:2019/metrics; echo "Exit code is $?"
curl: (35) TLS connect error: error:0A0000C6:SSL routines::packet length too long
Exit code is 35

[dunglas]

Can you use the long form of options for clarity please?

[7-zete-7]

@dunglas Converted the options to long form (including the --fail option).

Also moved the URL to the beginning of the command. IMO the URL gets lost after so many options.