Allow admins to control if/which weather advisories are sent to their groups

Right now (see #80), anything that shows up in the US NWS' API for a given zone is displayed. https://api.weather.gov/alerts/active?zone=WAZ558, for example, currently lists:

{
    "@context": [
        "https://raw.githubusercontent.com/geojson/geojson-ld/master/contexts/geojson-base.jsonld",
        {
            "wx": "https://api.weather.gov/ontology#",
            "@vocab": "https://api.weather.gov/ontology#"
        }
    ],
    "type": "FeatureCollection",
    "features": [
        {
            "id": "https://api.weather.gov/alerts/NWS-IDP-PROD-3968032",
            "type": "Feature",
            "geometry": null,
            "properties": {
                "@id": "https://api.weather.gov/alerts/NWS-IDP-PROD-3968032",
                "@type": "wx:Alert",
                "id": "NWS-IDP-PROD-3968032",
                "areaDesc": "Seattle and Vicinity; Everett and Vicinity; West Slopes North Central Cascades and Passes; Southwest Interior; Olympics; Central Coast; Bremerton and Vicinity; West Slopes North Cascades and Passes; North Coast; Lower Chehalis Valley Area; West Slopes South Central Cascades and Passes; Tacoma Area; Bellevue and Vicinity; East Puget Sound Lowlands; Hood Canal Area",
                "geocode": {
                    "UGC": [
                        "WAZ558",
                        "WAZ507",
                        "WAZ568",
                        "WAZ504",
                        "WAZ513",
                        "WAZ517",
                        "WAZ559",
                        "WAZ567",
                        "WAZ516",
                        "WAZ512",
                        "WAZ569",
                        "WAZ509",
                        "WAZ556",
                        "WAZ555",
                        "WAZ511"
                    ],
                    "SAME": [
                        "053033",
                        "053035",
                        "053061",
                        "053041",
                        "053067",
                        "053009",
                        "053027",
                        "053031",
                        "053045",
                        "053057",
                        "053073",
                        "053053"
                    ]
                },
                "affectedZones": [
                    "https://api.weather.gov/zones/forecast/WAZ558",
                    "https://api.weather.gov/zones/forecast/WAZ507",
                    "https://api.weather.gov/zones/forecast/WAZ568",
                    "https://api.weather.gov/zones/forecast/WAZ504",
                    "https://api.weather.gov/zones/forecast/WAZ513",
                    "https://api.weather.gov/zones/forecast/WAZ517",
                    "https://api.weather.gov/zones/forecast/WAZ559",
                    "https://api.weather.gov/zones/forecast/WAZ567",
                    "https://api.weather.gov/zones/forecast/WAZ516",
                    "https://api.weather.gov/zones/forecast/WAZ512",
                    "https://api.weather.gov/zones/forecast/WAZ569",
                    "https://api.weather.gov/zones/forecast/WAZ509",
                    "https://api.weather.gov/zones/forecast/WAZ556",
                    "https://api.weather.gov/zones/forecast/WAZ555",
                    "https://api.weather.gov/zones/forecast/WAZ511"
                ],
                "references": [],
                "sent": "2019-12-22T14:50:00-08:00",
                "effective": "2019-12-22T14:50:00-08:00",
                "onset": "2019-12-22T14:50:00-08:00",
                "expires": "2019-12-23T03:00:00-08:00",
                "ends": null,
                "status": "Actual",
                "messageType": "Alert",
                "category": "Met",
                "severity": "Moderate",
                "certainty": "Observed",
                "urgency": "Expected",
                "event": "Special Weather Statement",
                "sender": "w-nws.webmaster@noaa.gov",
                "senderName": "NWS Seattle WA",
                "headline": "Special Weather Statement issued December 22 at 2:50PM PST by NWS Seattle WA",
                "description": "Soil moisture will remain at high levels across western Washington\nin response to prolonged rainfall since Thursday. Although widespread\nrainfall has ended across western Washington, the landslide threat\nwill be elevated through early this week.\n\nFor more information about current conditions, visit\nwww.weather.gov/seattle, select Hydrology, and then scroll down\nfor the links to the landslide information pages.\n\nFor more information on landslides, visit the website for the\nWashington State Department of Natural Resources landslide\ngeologic hazards at: http://bit.ly/2mtA3wn",
                "instruction": null,
                "response": "Execute",
                "parameters": {
                    "NWSheadline": [
                        "INCREASED THREAT OF LANDSLIDES IN WESTERN WASHINGTON INTO EARLY THIS WEEK"
                    ],
                    "EAS-ORG": [
                        "WXR"
                    ],
                    "PIL": [
                        "SEWSPSSEW"
                    ],
                    "BLOCKCHANNEL": [
                        "CMAS",
                        "EAS",
                        "NWEM"
                    ]
                }
            }
        }
    ],
    "title": "current watches, warnings, and advisories for Seattle and Vicinity (WAZ558) WA",
    "updated": "2019-12-22T22:50:42+00:00"
}

which is not super urgent (or useful).

Each alert (or "feature") includes a messageType, category, severity, certainty, urgency, and response. These seem to correlate with the similarly named fields in Common Alerting Protocol Version 1.2:

msgType The code denoting the nature of the alert message (REQUIRED) Code Values:
- “Alert” - Initial information requiring attention by targeted recipients
- “Update” - Updates and supercedes the earlier message(s) identified in <references>
- “Cancel” - Cancels the earlier message(s) identified in <references>
- “Ack” - Acknowledges receipt and acceptance of the message(s) identified in <references>
- “Error” - Indicates rejection of the message(s) identified in <references>; explanation SHOULD appear in <note>
category The code denoting the category of the subject event of the alert message (REQUIRED) (1) Code Values:
- “Geo” - Geophysical (inc. landslide)
- “Met” - Meteorological (inc. flood)
- “Safety” - General emergency and public safety
- “Security” - Law enforcement, military, homeland and local/private security
- “Rescue” - Rescue and recovery
- “Fire” - Fire suppression and rescue
- “Health” - Medical and public health
- “Env” - Pollution and other environmental
- “Transport” - Public and private transportation
- “Infra” - Utility, telecommunication, other non-transport infrastructure
- “CBRNE” – Chemical, Biological, Radiological, Nuclear or High-Yield Explosive threat or attack
- “Other” - Other events
(2) Multiple instances MAY occur within an <info> block.
responseType The code denoting the type of action recommended for the target audience (OPTIONAL) (1) Code Values:
- “Shelter” – Take shelter in place or per <instruction>
- “Evacuate” – Relocate as instructed in the <instruction>
- “Prepare” – Make preparations per the <instruction>
- “Execute” – Execute a pre-planned activity identified in <instruction>
- “Avoid” – Avoid the subject event as per the <instruction>
- “Monitor” – Attend to information sources as described in <instruction>
- “Assess” – Evaluate the information in this message. (This value SHOULD NOT be used in public warning applications.)
- “AllClear” – The subject event no longer poses a threat or concern and any follow on action is described in <instruction>
- “None” – No action recommended
(2) Multiple instances MAY occur within an <info> block.
urgency The code denoting the urgency of the subject event of the alert message (REQUIRED) (1) The <urgency>, <severity>, and <certainty> elements collectively distinguish less emphatic from more emphatic messages. (2) Code Values:
- “Immediate” - Responsive action SHOULD be taken immediately
- “Expected” - Responsive action SHOULD be taken soon (within next hour)
- “Future” - Responsive action SHOULD be taken in the near future
- “Past” - Responsive action is no longer required
- “Unknown” - Urgency not known
severity The code denoting the severity of the subject event of the alert message (REQUIRED) (2) Code Values:
- “Extreme” - Extraordinary threat to life or property
- “Severe” - Significant threat to life or property
- “Moderate” - Possible threat to life or property
- “Minor” – Minimal to no known threat to life or property
- “Unknown” - Severity unknown
certainty The code denoting the certainty of the subject event of the alert message (REQUIRED) (2) Code Values:
- “Observed” – Determined to have occurred or to be ongoing
- “Likely” - Likely (p > ~50%)
- “Possible” - Possible but not likely (p <= ~50%)
- “Unlikely” - Not expected to occur (p ~ 0)
- “Unknown” - Certainty unknown
(3) For backward compatibility with CAP 1.0, the deprecated value of “Very Likely” SHOULD be treated as equivalent to “Likely”.

It might make sense to do something like: If a message has urgency=Immediate or Expected, post immediately; if urgency=Future, maybe only post as part of the daily announcement. However, it would be simpler to keep the posting behavior uniform but allow admins to filter events based on severity (maybe the default could be changed to exclude Minor or even Moderate, since the current landslide warning is set at that).

In addition/alternatively, it might make sense to simply ignore features that don't include an <instruction> string (as the landslide warning does not):

instruction The text describing the recommended action to be taken by recipients of the alert message (OPTIONAL) An extended human readable instruction to targeted recipients. If different instructions are intended for different recipients, they should be represented by use of multiple <info> blocks.

It might even make sense to prioritize/only show the instruction in the text posted to the group. (Currently, the bot posts the first 250 characters of the combined description, instruction, and areaDesc.)

Since #80 went live, 49 alerts have been processed by the bot. Unfortunately, api.weather.gov (and alerts-v2.weather.gov) seem to expire records pretty aggressively, so only the following 14 are still viewable (all had status=Actual and category=Met):

id	messageType	severity	certainty	urgency	event	response	instruction
3960241-3364815	Update	Moderate	Likely	Expected	Winter Weather Advisory	Execute	...
3960620-3365123	Update	Moderate	Likely	Expected	Winter Weather Advisory	Execute	...
3961136	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3961794	Alert	Unknown	Possible	Future	Hydrologic Outlook	Monitor	None
3963421-3367361	Alert	Severe	Possible	Future	Flood Watch	Prepare	...
3964821-3368352	Update	Severe	Possible	Future	Flood Watch	Prepare	...
3965155-3368578	Update	Severe	Possible	Future	Flood Watch	Prepare	...
3965324-3368680	Update	Severe	Possible	Future	Flood Watch	Prepare	...
3965613	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3965873-3369046	Update	Severe	Possible	Future	Flood Watch	Prepare	...
3966591	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3967196	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3968032	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3968722	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None

It's hard to determine exactly what the bot should be doing based on this data. For example, I would argue that NWS-IDP-PROD-3965613 should have definitely been posted, but all of the followups for WAZ558 (NWS-IDP-PROD-3966591, which was briefly live concurrently with 5613; NWS-IDP-PROD-3967196; NWS-IDP-PROD-3968032; and NWS-IDP-PROD-3968722) should have been suppressed. However, their primary features are identical:

id	messageType	severity	certainty	urgency	event	response	instruction
3965613	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3966591	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3967196	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3968032	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None
3968722	Alert	Moderate	Observed	Expected	Special Weather Statement	Execute	None

and none of them include a references list (which is consistent with them all being labeled messageType=Alert), so it becomes something more like keeping track of advisories and preventing posts that overlap an active (or reopen a recently active) one. (3966591 was posted while 3965613 was still active, while 3967196 was posted within an hour of 3966591 expiring, 3968722 was posted within an hour of 3968032 expiring, and 3968032 was posted more than an hour after 3967196 had expired.)

Going back to filtering alerts, it appears this label of "Special Weather Statement" is an alternative form of "Significant Weather Advisory", and this text is actually structured. It might make sense to actually just extract the last word of event and only post when it matches "Warning" (possibly after canonicalization). (Though it might be the case that a label of "Watch" necessarily means urgency=Future, "Advisory" (or "Outlook", or "Special Weather Statement") means severity<=Moderate, etc.—again, I wish I had more data.)

nmlorg / metabot

Allow admins to control if/which weather advisories are sent to their groups #85

id	messageType	severity	certainty	urgency	event	instruction
3969721	Alert	Moderate	Observed	Expected	Special Weather Statement	None
3969740-3371513	Alert	Moderate	Likely	Expected	Dense Fog Advisory	If drivin…
3969972-3371675	Update	Moderate	Likely	Expected	Dense Fog Advisory	If drivin…
3970041-3371724	Alert	Moderate	Likely	Expected	Dense Fog Advisory	If drivin…
3970132-3371798	Update	Moderate	Likely	Expected	Dense Fog Advisory	If drivin…
3970277-3371882	Update	Moderate	Likely	Expected	Dense Fog Advisory	If drivin…
3970377-3371943	Alert	Moderate	Likely	Expected	Beach Hazards Statement	A Beach H…
3970415-3371975	Alert	Moderate	Likely	Expected	Dense Fog Advisory	If drivin…