add FDroidMetricsWorker to gather data into JSON reports

app/src/test/java/org/fdroid/fdroid/work/FDroidMetricsWorkerTest.java

@@ -0,0 +1,96 @@
+package org.fdroid.fdroid.work;
+
+import android.app.Application;
+import android.content.ContextWrapper;
+import android.text.format.DateUtils;
+import androidx.test.core.app.ApplicationProvider;
+import org.apache.commons.io.FileUtils;
+import org.fdroid.fdroid.Preferences;
+import org.fdroid.fdroid.TestUtils;
+import org.fdroid.fdroid.installer.InstallHistoryService;
+import org.fdroid.fdroid.work.FDroidMetricsWorker.MatomoEvent;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.annotation.Config;
+
+import java.io.File;
+import java.io.IOException;
+import java.text.ParseException;
+import java.util.Collection;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertTrue;
+
+@Config(application = Application.class)
+@RunWith(RobolectricTestRunner.class)
+public class FDroidMetricsWorkerTest {
+    protected ContextWrapper context;
+
+    @Before
+    public final void setUp() {
+        context = ApplicationProvider.getApplicationContext();
+        Preferences.setupForTests(context);
+    }
+
+    @Test
+    public void testNormalizeTimestampToWeek() {
+        long startTime = 1610038865743L;
+        long endTime = 1610037631519L;
+
+        long normalizedStart = FDroidMetricsWorker.toCleanInsightsTimestamp(startTime);
+        long normalizedEnd = FDroidMetricsWorker.toCleanInsightsTimestamp(endTime);
+        assertEquals(normalizedStart, normalizedEnd);
+
+        long normalizedRelativeEnd = FDroidMetricsWorker.toCleanInsightsTimestamp(startTime, endTime);
+        assertEquals(1609976365L, normalizedRelativeEnd);
+    }
+
+    @Test
+    public void testGenerateReport() throws IOException {
+        String json = FDroidMetricsWorker.generateReport(context);
+        System.out.println(json);
+        File downloads = new File(System.getenv("HOME"), "Downloads");
+        if (downloads.exists()) {
+            File output = new File(downloads, getClass().getName() + ".testGenerateReport.json");
+            FileUtils.writeStringToFile(output, json);
+        }
+        // TODO validate against the schema
+    }
+
+    @Test
+    public void testParseInstallHistory() throws IOException {
+        FileUtils.copyFile(TestUtils.copyResourceToTempFile("install_history_all"),
+                InstallHistoryService.getInstallHistoryFile(context));
+        long weekStart = FDroidMetricsWorker.getReportingWeekStart(1611268892206L + DateUtils.WEEK_IN_MILLIS);
+        Collection<? extends MatomoEvent> events = FDroidMetricsWorker.parseInstallHistoryCsv(context,
+                weekStart);
+        assertEquals(3, events.size());
+        for (MatomoEvent event : events) {
+            assertEquals(event.name, "com.termux");
+        }
+
+        Collection<? extends MatomoEvent> oneWeekAgo = FDroidMetricsWorker.parseInstallHistoryCsv(context,
+                weekStart - DateUtils.WEEK_IN_MILLIS);
+        assertEquals(11, oneWeekAgo.size());
+
+        Collection<? extends MatomoEvent> twoWeeksAgo = FDroidMetricsWorker.parseInstallHistoryCsv(context,
+                weekStart - (2 * DateUtils.WEEK_IN_MILLIS));
+        assertEquals(0, twoWeeksAgo.size());
+
+        Collection<? extends MatomoEvent> threeWeeksAgo = FDroidMetricsWorker.parseInstallHistoryCsv(context,
+                weekStart - (3 * DateUtils.WEEK_IN_MILLIS));
+        assertEquals(9, threeWeeksAgo.size());
+        assertNotEquals(oneWeekAgo, threeWeeksAgo);
+    }
+
+    @Test
+    public void testGetReportingWeekStart() throws ParseException {
+        long now = System.currentTimeMillis();
+        long start = FDroidMetricsWorker.getReportingWeekStart(now);
+        assertTrue((now - DateUtils.WEEK_IN_MILLIS) > start);
+        assertTrue((now - DateUtils.WEEK_IN_MILLIS) < (start + DateUtils.WEEK_IN_MILLIS));
+    }
+}