🐛 Fixed flat member chart for GMT-X timezones

closes #12083

- fixes a parsing issue where negative offset values were incorrectly having the + sign added regardless of actual offset for sqlite databases.
- for mysql databases absolute values of offset were taken with sign applied where appropriate to stop issues where both hours and minutes could be negative which would cause both an issue with offsets that could present as -2:30 and by the look of the code also trigger extra padding to result in -2:-030 rather than the expected -2:30

core/server/api/canary/members.js

@@ -733,7 +733,7 @@ module.exports = {
                 let result;
 
                 if (isSQLite) {
-                    const dateModifier = `+${tzOffsetMins} minutes`;
+                    const dateModifier = `${Math.sign(tzOffsetMins) === -1 ? '' : '+'}${tzOffsetMins} minutes`;
 
                     result = await db.knex('members')
                         .select(db.knex.raw('DATE(created_at, ?) AS created_at, COUNT(DATE(created_at, ?)) AS count', [dateModifier, dateModifier]))
@@ -743,8 +743,8 @@ module.exports = {
                             }
                         }).groupByRaw('DATE(created_at, ?)', [dateModifier]);
                 } else {
-                    const mins = tzOffsetMins % 60;
-                    const hours = (tzOffsetMins - mins) / 60;
+                    const mins = Math.abs(tzOffsetMins) % 60;
+                    const hours = (Math.abs(tzOffsetMins) - mins) / 60;
                     const utcOffset = `${Math.sign(tzOffsetMins) === -1 ? '-' : '+'}${hours}:${mins < 10 ? '0' : ''}${mins}`;
 
                     result = await db.knex('members')

test/api-acceptance/admin/members_spec.js

@@ -7,6 +7,8 @@ const localUtils = require('./utils');
 const config = require('../../../core/shared/config');
 const labs = require('../../../core/server/services/labs');
 const Papa = require('papaparse');
+const settingsCache = require('../../../core/server/services/settings/cache');
+const moment = require('moment-timezone');
 
 const ghost = testUtils.startGhost;
 
@@ -425,7 +427,7 @@ describe('Members API', function () {
             });
     });
 
-    it('Can fetch stats', function () {
+    function fetchStats() {
         return request
             .get(localUtils.API.getApiQuery('members/stats/'))
             .set('Origin', config.get('url'))
@@ -444,6 +446,81 @@ describe('Members API', function () {
 
                 // 4 from fixtures, 2 from above posts, 2 from above import
                 jsonResponse.total.should.equal(8);
+
+                return jsonResponse;
+            });
+    }
+
+    function parseTotalOnDate(jsonResponse) {
+        // replicate default look back date of 30 days
+        const days = 30;
+        // grab the timezone as mocked above
+        const siteTimezone = settingsCache.get('timezone');
+
+        // rebuild a valid response object such that works on any date-time...
+        // get the start date
+        let currentRangeDate = moment.tz(siteTimezone).subtract(days - 1, 'days');
+        // get the end date but ignore today because we want to set that value ourselves
+        let endDate = moment.tz(siteTimezone).subtract(1, 'hour');
+
+        const output = {};
+        let dateStr;
+
+        // set user count to be 1 for all dates before today to match date as outlined
+        // for the user in valid-members-import.csv who was imported with a start date of '91
+        while (currentRangeDate.isBefore(endDate)) {
+            dateStr = currentRangeDate.format('YYYY-MM-DD');
+            output[dateStr] = 1;
+
+            currentRangeDate = currentRangeDate.add(1, 'day');
+        }
+
+        // format the date for the end date (right now)
+        dateStr = currentRangeDate.format('YYYY-MM-DD');
+
+        // set the end date to match the number of members added from fixtures posts and imports
+        // 4 from fixtures, 2 from above posts, 2 from above import
+        output[dateStr] = 8;
+
+        // deep equality check that the objects match...
+        jsonResponse.total_on_date.should.eql(output);
+    }
+
+    it('Can fetch stats', function () {
+        return fetchStats();
+    });
+
+    it('Can render stats in GMT -X timezones', function () {
+        // stub the method
+        const stub = sinon.stub(settingsCache, 'get');
+        
+        // this was just a GMT -X Timezone picked at random for the test below...
+        stub
+            .withArgs('timezone')
+            .returns('America/Caracas');
+        
+        return fetchStats()
+            .then((jsonResponse) => {
+                parseTotalOnDate(jsonResponse);
+                // restore the stub so we can use it in other tests
+                stub.restore();
+            });
+    });
+
+    it('Can render stats in GMT +X timezones', function () {
+        // stub the method
+        const stub = sinon.stub(settingsCache, 'get');
+
+        // the tester that wrote this lives in Adelaide so shoutout to this (random) timezone!
+        stub
+            .withArgs('timezone')
+            .returns('Australia/Adelaide');
+
+        return fetchStats()
+            .then((jsonResponse) => {
+                parseTotalOnDate(jsonResponse);
+                // restore the stub so we can use it in other tests
+                stub.restore();
             });
     });
 });