[Synthetics] Support project lightweight 10 and 30 seconds schedules (#185920)

## Summary

Companion PR to https://github.com/elastic/synthetics/pull/932

x-pack/plugins/observability_solution/synthetics/common/runtime_types/monitor_management/monitor_types_project.ts

@@ -6,9 +6,23 @@
  */
 
 import * as t from 'io-ts';
+import { Either } from 'fp-ts/Either';
 import { AlertConfigsCodec } from './alert_config';
 import { ScreenshotOptionCodec } from './monitor_configs';
 
+const ProjectMonitorSchedule = new t.Type<string | number, string | number, unknown>(
+  'ProjectMonitorSchedule',
+  t.string.is,
+  (input, context): Either<t.Errors, string | number> => {
+    if (typeof input === 'number' || input === '10s' || input === '30s') {
+      return t.success(input);
+    } else {
+      return t.failure(input, context);
+    }
+  },
+  t.identity
+);
+
 export const ProjectMonitorThrottlingConfigCodec = t.union([
   t.interface({
     download: t.number,
@@ -23,7 +37,7 @@ export const ProjectMonitorCodec = t.intersection([
     type: t.string,
     id: t.string,
     name: t.string,
-    schedule: t.number,
+    schedule: ProjectMonitorSchedule,
   }),
   t.partial({
     content: t.string,

x-pack/plugins/observability_solution/synthetics/server/synthetics_service/project_monitor/normalizers/common_fields.ts

@@ -75,10 +75,7 @@ export const getNormalizeCommonFields = ({
     [ConfigKey.JOURNEY_ID]: monitor.id || defaultFields[ConfigKey.JOURNEY_ID],
     [ConfigKey.MONITOR_SOURCE_TYPE]: SourceType.PROJECT,
     [ConfigKey.NAME]: monitor.name || '',
-    [ConfigKey.SCHEDULE]: {
-      number: `${monitor.schedule}`,
-      unit: ScheduleUnit.MINUTES,
-    },
+    [ConfigKey.SCHEDULE]: getMonitorSchedule(monitor.schedule, defaultFields[ConfigKey.SCHEDULE]),
     [ConfigKey.PROJECT_ID]: projectId,
     [ConfigKey.LOCATIONS]: monLocations,
     [ConfigKey.TAGS]: getOptionalListField(monitor.tags) || defaultFields[ConfigKey.TAGS],
@@ -145,8 +142,27 @@ export const getCustomHeartbeatId = (
   return `${monitor.id}-${projectId}-${namespace}`;
 };
 
-export const getMonitorSchedule = (schedule: number | string | MonitorFields['schedule']) => {
+export const getMonitorSchedule = (
+  schedule: number | string | MonitorFields['schedule'],
+  defaultValue?: MonitorFields['schedule']
+) => {
+  if (!schedule && defaultValue) {
+    return defaultValue;
+  }
   if (typeof schedule === 'number' || typeof schedule === 'string') {
+    if (typeof schedule === 'number') {
+      return {
+        number: `${schedule}`,
+        unit: ScheduleUnit.MINUTES,
+      };
+    }
+    if (schedule.includes('s')) {
+      return {
+        number: schedule.replace('s', ''),
+        unit: ScheduleUnit.SECONDS,
+      };
+    }
+
     return {
       number: `${schedule}`,
       unit: ScheduleUnit.MINUTES,

x-pack/plugins/observability_solution/synthetics/server/synthetics_service/project_monitor/project_monitor_formatter.test.ts

@@ -194,6 +194,40 @@ describe('ProjectMonitorFormatter', () => {
       updatedMonitors: [],
     });
   });
+  it('should return invalid schedule error', async () => {
+    const invalidMonitor = {
+      ...testMonitors[0],
+      schedule: '3m',
+    };
+    const pushMonitorFormatter = new ProjectMonitorFormatter({
+      projectId: 'test-project',
+      spaceId: 'default',
+      routeContext,
+      encryptedSavedObjectsClient,
+      monitors: [invalidMonitor],
+    });
+
+    pushMonitorFormatter.getProjectMonitorsForProject = jest.fn().mockResolvedValue([]);
+
+    await pushMonitorFormatter.configureAllProjectMonitors();
+
+    expect({
+      createdMonitors: pushMonitorFormatter.createdMonitors,
+      updatedMonitors: pushMonitorFormatter.updatedMonitors,
+      failedMonitors: pushMonitorFormatter.failedMonitors,
+    }).toStrictEqual({
+      createdMonitors: [],
+      failedMonitors: [
+        {
+          details: 'Invalid value "3m" supplied to "schedule"',
+          id: 'check if title is present 10 0',
+          payload: invalidMonitor,
+          reason: "Couldn't save or update monitor because of an invalid configuration.",
+        },
+      ],
+      updatedMonitors: [],
+    });
+  });
 
   it('catches errors from bulk edit method', async () => {
     soClient.bulkCreate.mockImplementation(async () => {