Bug 1851698 - Update default maxEvents to 1

changelog
- set the default `maxEvents` number to 1
- update existing tests that rely on having more than 1 event
- update comments in `pings.yaml`

glean/src/core/config.ts

@@ -11,9 +11,9 @@ import { Context } from "./context.js";
 
 const LOG_TAG = "core.Config";
 
-// The default maximum number of events Glean will store before submitting the events ping.
-// If the maximum is hit, the events ping is sent immediately.
-const DEFAULT_MAX_EVENTS = 500;
+// By default we want to send the events ping after every event is recorded. Unless the user
+// explicitly sets a higher value, we will send the events ping after every event.
+const DEFAULT_MAX_EVENTS = 1;
 
 /**
  * Lists Glean's debug options.

glean/src/pings.yaml

@@ -41,7 +41,7 @@ events:
     from the previous application run in storage.
     It is also sent when maximum capacity is hit
     i.e. when a given number of events is in storage.
-    Maximum capacity defaults to 500,
+    Maximum capacity defaults to 1,
     but may be changed through the `maxEvents` configuration option.
   include_client_id: true
   bugs:
@@ -56,7 +56,7 @@ events:
       The events ping is always sent if there are any pending events at startup,
       because event timestamps are not as reliable across application runs.
     max_capacity: |
-      The maximum number of events was reached (default 500 events).
+      The maximum number of events was reached (default 1 event).
     inactive: |
       The ping was submitted when becoming inactive. In earlier versions, this
       was called `background`.

glean/tests/unit/core/metrics/events_database.spec.ts

@@ -755,6 +755,8 @@ describe("EventsDatabase", function() {
     // Restore timer APIs for WaitableUploader to work
     clock.restore();
 
+    await testResetGlean(testAppId, true, { maxEvents: 500 });
+
     const event = new EventMetricType({
       category: "test",
       name: "event",
@@ -780,6 +782,8 @@ describe("EventsDatabase", function() {
     // Restore timer APIs for WaitableUploader to work
     clock.restore();
 
+    await testResetGlean(testAppId, true, { maxEvents: 500 });
+
     const previousRunEvent = new EventMetricType({
       category: "test",
       name: "previousRun",
@@ -809,7 +813,7 @@ describe("EventsDatabase", function() {
     const httpClient = new WaitableUploader();
     const waitForEventsPings = httpClient.waitForBatchPingSubmission(EVENTS_PING_NAME, 2);
     // Initialization should trigger a startup ping
-    await testInitializeGlean(testAppId, true, { httpClient });
+    await testInitializeGlean(testAppId, true, { httpClient, maxEvents: 500 });
     // Send another 'events' ping after init, it should contain the preInit events
     await Context.corePings.events.submitUndispatched();