feat(geo): switch geocoder from self-host Photon to OpenCage API

logic_geo проксирует OpenCage (suggest/geocode/reverse): env OPENCAGE_API_KEY,
OPENCAGE_URL, OPENCAGE_TIMEOUT_MS, OPENCAGE_COUNTRYCODE, OPENCAGE_THROTTLE_RPS
(1 rps под free-тариф, 0 - выключить). HTTP 402/403/429 апстрима ->
503 geo_unavailable; source=opencage. Сервис photon и volume photon-data
удалены из swarm compose; eunit-фикстуры под формат OpenCage.

Refs EventHub/EventHubBack#77

test/unit/logic_geo_tests.erl

@@ -4,16 +4,22 @@
 setup() ->
   catch ets:delete(eventhub_geo_cache),
   catch ets:delete(eventhub_geo_rl),
+  catch ets:delete(eventhub_geo_upstream),
   logic_geo:ensure(),
   application:unset_env(eventhub, geo_http_get),
-  os:putenv("PHOTON_URL", "http://photon.test"),
+  os:putenv("OPENCAGE_API_KEY", "test-key"),
+  os:putenv("OPENCAGE_URL", "http://opencage.test/geocode/v1/json"),
+  os:putenv("OPENCAGE_THROTTLE_RPS", "0"),
   ok.
 
 cleanup(_) ->
   application:unset_env(eventhub, geo_http_get),
-  os:unsetenv("PHOTON_URL"),
+  os:unsetenv("OPENCAGE_API_KEY"),
+  os:unsetenv("OPENCAGE_URL"),
+  os:unsetenv("OPENCAGE_THROTTLE_RPS"),
   catch ets:delete(eventhub_geo_cache),
   catch ets:delete(eventhub_geo_rl),
+  catch ets:delete(eventhub_geo_upstream),
   ok.
 
 logic_geo_test_() ->
@@ -22,22 +28,21 @@ logic_geo_test_() ->
     fun cleanup/1,
     [
       {"Suggest too short", fun test_suggest_short/0},
-      {"Suggest parses photon geojson", fun test_suggest_ok/0},
-      {"Geocode empty features is not_found", fun test_geocode_not_found/0},
-      {"Unavailable without photon url", fun test_unavailable/0},
+      {"Suggest parses opencage results", fun test_suggest_ok/0},
+      {"Geocode empty results is not_found", fun test_geocode_not_found/0},
+      {"Unavailable without opencage key", fun test_unavailable/0},
+      {"Upstream quota (402) is unavailable", fun test_quota_exceeded/0},
       {"Reverse fallback address", fun test_reverse_empty/0},
       {"Format address from properties", fun test_format_address/0}
     ]}.
 
-sample_geojson() ->
+sample_opencage() ->
   <<"{
-    \"features\": [{
-      \"geometry\": {\"coordinates\": [37.62, 55.75]},
-      \"properties\": {
-        \"name\": \"Red Square\",
-        \"city\": \"Moscow\",
-        \"country\": \"Russia\"
-      }
+    \"status\": {\"code\": 200, \"message\": \"OK\"},
+    \"results\": [{
+      \"formatted\": \"Red Square, Moscow, Russia\",
+      \"geometry\": {\"lat\": 55.75, \"lng\": 37.62},
+      \"components\": {\"city\": \"Moscow\", \"country\": \"Russia\"}
     }]
   }">>.
 
@@ -45,27 +50,35 @@ test_suggest_short() ->
   ?assertEqual({error, invalid_query}, logic_geo:suggest(<<"ab">>, <<"ru">>, <<"ip">>)).
 
 test_suggest_ok() ->
-  application:set_env(eventhub, geo_http_get, fun(_) -> {ok, sample_geojson()} end),
+  application:set_env(eventhub, geo_http_get, fun(_) -> {ok, sample_opencage()} end),
   {ok, Hits} = logic_geo:suggest(<<"красная площадь">>, <<"ru">>, <<"ip1">>),
   ?assertMatch([#{<<"lat">> := 55.75, <<"lon">> := 37.62}], Hits),
   [#{<<"address">> := Addr}] = Hits,
-  ?assertNotEqual(<<>>, Addr).
+  ?assertEqual(<<"Red Square, Moscow, Russia">>, Addr).
 
 test_geocode_not_found() ->
-  application:set_env(eventhub, geo_http_get, fun(_) -> {ok, <<"{\"features\":[]}">>} end),
+  application:set_env(eventhub, geo_http_get,
+    fun(_) -> {ok, <<"{\"status\":{\"code\":200},\"results\":[]}">>} end),
   ?assertEqual({error, not_found},
     logic_geo:geocode(<<"nowherexyz">>, <<"ru">>, <<"u1">>)).
 
 test_unavailable() ->
-  os:unsetenv("PHOTON_URL"),
+  os:unsetenv("OPENCAGE_API_KEY"),
   application:unset_env(eventhub, geo_http_get),
   ?assertEqual({error, unavailable},
     logic_geo:suggest(<<"москва центр">>, <<"ru">>, <<"ip2">>)).
 
+test_quota_exceeded() ->
+  application:set_env(eventhub, geo_http_get,
+    fun(_) -> {error, {http_status, 402}} end),
+  ?assertEqual({error, unavailable},
+    logic_geo:suggest(<<"москва центр">>, <<"ru">>, <<"ip3">>)).
+
 test_reverse_empty() ->
-  application:set_env(eventhub, geo_http_get, fun(_) -> {ok, <<"{\"features\":[]}">>} end),
+  application:set_env(eventhub, geo_http_get,
+    fun(_) -> {ok, <<"{\"status\":{\"code\":200},\"results\":[]}">>} end),
   {ok, Hit} = logic_geo:reverse(55.75, 37.62, <<"ru">>, <<"u2">>),
-  ?assertEqual(<<"photon">>, maps:get(<<"source">>, Hit)),
+  ?assertEqual(<<"opencage">>, maps:get(<<"source">>, Hit)),
   ?assertEqual(55.75, maps:get(<<"lat">>, Hit)).
 
 test_format_address() ->