fix(update): correct dl url and resolve longitude 0 zones

- updates to use the correct data download url so that data without the oceans is used
- implements a small hack so that antarctic zones along longitude 0 will not be intersected into LineStrings during the geo-index.

fixes #90

lib/geo-index.js

@@ -21,9 +21,50 @@ module.exports = function (tzGeojson, dataDir, targetIndexPercent, callback) {
     lookup: {}
   }
 
-  const timezoneGeometries = tzGeojson.features.map(feature =>
-    geoJsonReader.read(JSON.stringify(feature.geometry))
-  )
+  /**
+   * iterate through geometry coordinates and change any coordinates along
+   * longitude 0 to longitude 0.00001
+   */
+  function hackLongitude0Polygon (polygon) {
+    polygon.forEach(linearRing => {
+      linearRing.forEach(ringCoords => {
+        if (ringCoords[0] === 0 && ringCoords[1] < -55) {
+          ringCoords[0] = 0.00001
+        }
+      })
+    })
+  }
+
+  const timezoneGeometries = tzGeojson.features.map(feature => {
+    // Perform a quick hack to make sure two Antarctic zones can be indexed
+    // properly. Each of these zones shares a boundary at longitude 0. During
+    // the quadtree analysis, the zones were being intersected right aloing
+    // their boundaries which resulted in LineStrings being returned. This hack
+    // changes their boundares along longitude 0 to longitude 0.00001 to avoid
+    // LineStrings being intersected.
+    if (
+      feature.properties.tzid === 'Africa/Johannesburg' ||
+        feature.properties.tzid === 'Antarctica/Troll'
+    ) {
+      if (feature.geometry.type === 'MultiPolygon') {
+        feature.geometry.coordinates.forEach(hackLongitude0Polygon)
+      } else {
+        hackLongitude0Polygon(feature.geometry.coordinates)
+      }
+    }
+
+    // load zone into memory as jsts geometry
+    return geoJsonReader.read(JSON.stringify(feature.geometry))
+  })
+
+  var debugWriteIdx = 1
+
+  var writeDebugData = function (filename, geom) {
+    fs.writeFileSync(
+      'debug_' + debugWriteIdx + '_' + filename + '.json',
+      JSON.stringify(geoJsonWriter.write(geom))
+    )
+  }
 
   var getIntersectingGeojson = function (tzIdx, curBoundsGeometry) {
     // console.log('intersecting', tzGeojson.features[tzIdx].properties)
@@ -36,6 +77,19 @@ module.exports = function (tzGeojson, dataDir, targetIndexPercent, callback) {
     ) {
       return undefined
     } else {
+      const tzName = data.timezones[tzIdx]
+      // If the geojson type is not a Polygon or a MultiPolygon, something weird
+      // is happening and the build should be failed as this will cause issues
+      // during the find method.
+      // See https://github.com/evansiroky/node-geo-tz/issues/90.
+      if (!intersectedGeoJson.type.match(/olyg/)) {
+        console.log(tzName)
+        console.log(intersectedGeoJson.type)
+        writeDebugData('tz', timezoneGeometries[tzIdx])
+        writeDebugData('curBounds', curBoundsGeometry)
+        writeDebugData('intersection', intersectedGeometry)
+        debugWriteIdx++
+      }
       return {
         type: 'Feature',
         properties: {},
@@ -355,7 +409,13 @@ module.exports = function (tzGeojson, dataDir, targetIndexPercent, callback) {
 
   fileWritingQueue.drain = function (err) {
     console.log('done indexing')
-    callback(err)
+    callback(
+      err || (
+        debugWriteIdx > 1
+          ? 'At least one unexpected intersected geometry type encountered!'
+          : null
+      )
+    )
   }
 
   // write index data to file

lib/update.js

@@ -32,8 +32,9 @@ var downloadLatest = function (callback) {
           res.on('end', function () {
             data = JSON.parse(data)
             for (var i = 0; i < data.assets.length; i++) {
-              data.assets[i].browser_download_url.indexOf('timezones.geojson') > -1
-              return cb(null, data.assets[i].browser_download_url)
+              if (data.assets[i].browser_download_url.indexOf('timezones.geojson') > -1) {
+                return cb(null, data.assets[i].browser_download_url)
+              }
             }
             cb('geojson not found')
           })

tests/fixtures/issues.json

@@ -139,5 +139,15 @@
     "lat": 22.138993,
     "lon": 31.416836,
     "description": "#89 - 2019a - test for zone Asia/Khartoum in Sudanese part of Lake Nasser"
+  }, {
+    "zid": "America/Adak",
+    "lat": 52.031192,
+    "lon": 178.913872,
+    "description": "#90 - some file-based data was showing up as non-polygon geojson"
+  }, {
+    "zids": ["Africa/Johannesburg", "Antarctica/McMurdo", "Antarctica/Troll"],
+    "lat": -86,
+    "lon": 0.00001,
+    "description": "#90 - timezones that share the same corner should all be found when the coordinate corner is queried"
   }
 ]