NWWS Client

NWWS Client receives and stores NWS text bulletins from the NOAA Weather Wire Service Open Interface (NWWS-OI).

NWWS information: https://www.weather.gov/nwws/

Description

Current version: 0.3

NWWS Client is designed for operators who need a simple service that:

• stays connected to NWWS-OI
• writes incoming bulletins to disk
• reconnects automatically when needed
• provides configurable logs for operations and troubleshooting

Getting Started

Request NWWS-OI access: https://www.weather.gov/nwws/nwws_oi_request

Dependencies

• libstrophe-dev (0.10+)
• libexpat1-dev
• libssl-dev
• gcc
• make

Build

make            # default debug build (ASan + analyzer)
make debug      # explicit debug build
make release    # optimized build with -DNDEBUG

Run

./nwws_client <username@...> <nwws_password>

Example:

./nwws_client user@nwws-oi.weather.gov 'your-password'

What The Client Does

• Connects to nwws-oi.weather.gov:5222 via libstrophe
• Joins nwws@conference.nwws-oi.weather.gov/<user name>
• Parses incoming message stanzas and writes valid bulletins to files
• Uses timed health checks and XMPP pings
• Reconnects on disconnect/health-check failure/SIGPIPE unless shutdown is requested

Bulletin Storage

• Base output directory is currently hardcoded in code.
• Bulletins are written under per-center directories (lowercased cccc)
• File naming pattern: cccc-ttaaii_awipsid-id.txt (lowercased path/filename)

TODO

• Move hardcoded runtime settings (including output directory and conference resource/user name) into a configuration file.

Monitoring Signal

• If no valid bulletin was written during the alarm interval, the client creates /tmp/nwws_alarm.txt and sets reconnect requested state.

Logging

Application logs are written to stderr with this format:

[LEVEL] message

Supported levels:

• error
• warn (or warning)
• info
• debug

Set with:

export NWWS_LOG_LEVEL=debug

Default log level:

• debug builds (make/make debug): debug
• release builds (make release): info

Notes:

• Application logging level only controls messages from log.c.
• Libstrophe logging is initialized at XMPP_LEVEL_INFO in current code.

Environment Variables

• NWWS_LOG_LEVEL
• NWWS_PING_INTERVAL_MINUTES
• NWWS_ALARM_INTERVAL_SECONDS

Validation rules currently in code:

• NWWS_PING_INTERVAL_MINUTES: integer 1..1440
• NWWS_ALARM_INTERVAL_SECONDS: integer 1..86400
• Invalid values generate warnings and fall back to defaults.

Version History

• 0.3
• README restructured for customer/operator use
• logging and runtime options documented from current implementation
• 0.2
• various bug fixes and optimizations
• 0.1
• initial release

Authors

Adam Young
ay@fizhoo.com

Commits: https://github.com/fizhoo/nwws-client/commits/main

License

This project is licensed under the MIT License. See LICENSE.

Acknowledgments

• libstrophe examples: https://github.com/strophe/libstrophe/tree/master/examples

Appendix: Developer Notes

Source Map (Files and Functions)

• nwws_client.c: main, sigSetup, sigHandler
• xmpp_connect.c: nwws_connect_new, nwws_connect, nwws_disconnect
• xmpp_connect.c internals: stanza_attributes_missing, message_handler, conn_handler, nwws_connect_with_retry, nwws_run_loop
• xmpp_ping.c: xmpp_ping_configure_interval, xmpp_ping_interval_ms, xmpp_ping_reset_state, xmpp_ping_timed_handler, xmpp_ping_stanza_handler
• alarm_timer.c: alarm_interval_ms, alarm_timed_handler
• file_io.c: write_data
• text_utils.c: chomp
• log.c: log_init, log_set_level, log_get_level, log_message, log_level_label, level_from_env