[Security Solutions][Detection Engine] Fixes timestamp bugs within so…

…urce indexes when the formats are not ISO8601 format (elastic#101349)

## Summary

We have a few bugs where when the source index for detections is not `"strict_date_optional_time"` it is possible that we will misinterpret the format to be epoch milliseconds when it could be epoch seconds or another ambiguous format or blow up when trying to write out the signals index. This fixes it to where we query for the source index format as an ISO8601 and when we copy the date time format we copy it back out as ISO8601 and insert it into the signal index as ISO8601.

See this [gist](https://gist.github.com/FrankHassanabad/f614ec9762d59cd1129b3269f5bae41c) for more details of how this was accidentally introduced when we added support for runtime fields and the general idea of the fix.

* Removes `docvalue_field` and we now only use `fields` in detection engine search requests
* Splits out the timestamp e2e tests into their own file for `timestamps` file
* Adds more tests to ensure we copy what we expect and we are converting to ISO8601 in the signals
* Removes `ts-expect-error` in a lot of areas including tests and then I fix the types and issues once it is removed. 

### Checklist

- [x] [Unit or functional tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html) were updated or added to match the most common scenarios

x-pack/plugins/security_solution/server/lib/detection_engine/signals/__mocks__/es_results.ts

@@ -146,7 +146,7 @@ export const sampleDocWithSortId = (
 export const sampleDocNoSortId = (
   someUuid: string = sampleIdGuid,
   ip?: string
-): SignalSourceHit => ({
+): SignalSourceHit & { _source: Required<SignalSourceHit>['_source'] } => ({
   _index: 'myFakeSignalIndex',
   _type: 'doc',
   _score: 100,
@@ -225,12 +225,12 @@ export const sampleWrappedSignalHit = (): WrappedSignalHit => {
   };
 };
 
-export const sampleDocWithAncestors = (): SignalSearchResponse => {
+export const sampleDocWithAncestors = (): SignalSearchResponse & {
+  hits: { hits: Array<ReturnType<typeof sampleDocNoSortId>> };
+} => {
   const sampleDoc = sampleDocNoSortId();
   delete sampleDoc.sort;
-  // @ts-expect-error @elastic/elasticsearch _source is optional
   delete sampleDoc._source.source;
-  // @ts-expect-error @elastic/elasticsearch _source is optional
   sampleDoc._source.signal = {
     parent: {
       id: 'd5e8eb51-a6a0-456d-8a15-4b79bfec3d71',
@@ -562,7 +562,9 @@ export const sampleBulkCreateErrorResult = {
 
 export const sampleDocSearchResultsNoSortId = (
   someUuid: string = sampleIdGuid
-): SignalSearchResponse => ({
+): SignalSearchResponse & {
+  hits: { hits: Array<ReturnType<typeof sampleDocNoSortId>> };
+} => ({
   took: 10,
   timed_out: false,
   _shards: {

x-pack/plugins/security_solution/server/lib/detection_engine/signals/build_bulk_body.test.ts

@@ -24,6 +24,11 @@ import { SignalHit, SignalSourceHit } from './types';
 import { SIGNALS_TEMPLATE_VERSION } from '../routes/index/get_signals_template';
 import { getQueryRuleParams, getThresholdRuleParams } from '../schemas/rule_schemas.mock';
 
+// This allows us to not have to use ts-expect-error with delete in the code.
+type SignalHitOptionalTimestamp = Omit<SignalHit, '@timestamp'> & {
+  '@timestamp'?: SignalHit['@timestamp'];
+};
+
 describe('buildBulkBody', () => {
   beforeEach(() => {
     jest.clearAllMocks();
@@ -32,11 +37,9 @@ describe('buildBulkBody', () => {
   test('bulk body builds well-defined body', () => {
     const ruleSO = sampleRuleSO(getQueryRuleParams());
     const doc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete doc._source.source;
-    const fakeSignalSourceHit = buildBulkBody(ruleSO, doc);
+    const fakeSignalSourceHit: SignalHitOptionalTimestamp = buildBulkBody(ruleSO, doc);
     // Timestamp will potentially always be different so remove it for the test
-    // @ts-expect-error
     delete fakeSignalSourceHit['@timestamp'];
     const expected: Omit<SignalHit, '@timestamp'> & { someKey: 'someValue' } = {
       someKey: 'someValue',
@@ -69,7 +72,7 @@ describe('buildBulkBody', () => {
             depth: 0,
           },
         ],
-        original_time: '2020-04-20T21:27:45+0000',
+        original_time: '2020-04-20T21:27:45.000Z',
         status: 'open',
         rule: expectedRule(),
         depth: 1,
@@ -81,9 +84,8 @@ describe('buildBulkBody', () => {
   test('bulk body builds well-defined body with threshold results', () => {
     const ruleSO = sampleRuleSO(getThresholdRuleParams());
     const baseDoc = sampleDocNoSortId();
-    const doc: SignalSourceHit = {
+    const doc: SignalSourceHit & { _source: Required<SignalSourceHit>['_source'] } = {
       ...baseDoc,
-      // @ts-expect-error @elastic/elasticsearch _source is optional
       _source: {
         ...baseDoc._source,
         threshold_result: {
@@ -96,11 +98,9 @@ describe('buildBulkBody', () => {
         },
       },
     };
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete doc._source.source;
-    const fakeSignalSourceHit = buildBulkBody(ruleSO, doc);
+    const fakeSignalSourceHit: SignalHitOptionalTimestamp = buildBulkBody(ruleSO, doc);
     // Timestamp will potentially always be different so remove it for the test
-    // @ts-expect-error
     delete fakeSignalSourceHit['@timestamp'];
     const expected: Omit<SignalHit, '@timestamp'> & { someKey: 'someValue' } = {
       someKey: 'someValue',
@@ -133,7 +133,7 @@ describe('buildBulkBody', () => {
             depth: 0,
           },
         ],
-        original_time: '2020-04-20T21:27:45+0000',
+        original_time: '2020-04-20T21:27:45.000Z',
         status: 'open',
         rule: {
           ...expectedRule(),
@@ -167,18 +167,15 @@ describe('buildBulkBody', () => {
   test('bulk body builds original_event if it exists on the event to begin with', () => {
     const ruleSO = sampleRuleSO(getQueryRuleParams());
     const doc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete doc._source.source;
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     doc._source.event = {
       action: 'socket_opened',
       module: 'system',
       dataset: 'socket',
       kind: 'event',
     };
-    const fakeSignalSourceHit = buildBulkBody(ruleSO, doc);
+    const fakeSignalSourceHit: SignalHitOptionalTimestamp = buildBulkBody(ruleSO, doc);
     // Timestamp will potentially always be different so remove it for the test
-    // @ts-expect-error
     delete fakeSignalSourceHit['@timestamp'];
     const expected: Omit<SignalHit, '@timestamp'> & { someKey: 'someValue' } = {
       someKey: 'someValue',
@@ -220,7 +217,7 @@ describe('buildBulkBody', () => {
             depth: 0,
           },
         ],
-        original_time: '2020-04-20T21:27:45+0000',
+        original_time: '2020-04-20T21:27:45.000Z',
         status: 'open',
         rule: expectedRule(),
         depth: 1,
@@ -232,17 +229,14 @@ describe('buildBulkBody', () => {
   test('bulk body builds original_event if it exists on the event to begin with but no kind information', () => {
     const ruleSO = sampleRuleSO(getQueryRuleParams());
     const doc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete doc._source.source;
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     doc._source.event = {
       action: 'socket_opened',
       module: 'system',
       dataset: 'socket',
     };
-    const fakeSignalSourceHit = buildBulkBody(ruleSO, doc);
+    const fakeSignalSourceHit: SignalHitOptionalTimestamp = buildBulkBody(ruleSO, doc);
     // Timestamp will potentially always be different so remove it for the test
-    // @ts-expect-error
     delete fakeSignalSourceHit['@timestamp'];
     const expected: Omit<SignalHit, '@timestamp'> & { someKey: 'someValue' } = {
       someKey: 'someValue',
@@ -283,7 +277,7 @@ describe('buildBulkBody', () => {
             depth: 0,
           },
         ],
-        original_time: '2020-04-20T21:27:45+0000',
+        original_time: '2020-04-20T21:27:45.000Z',
         status: 'open',
         rule: expectedRule(),
         depth: 1,
@@ -295,15 +289,12 @@ describe('buildBulkBody', () => {
   test('bulk body builds original_event if it exists on the event to begin with with only kind information', () => {
     const ruleSO = sampleRuleSO(getQueryRuleParams());
     const doc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete doc._source.source;
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     doc._source.event = {
       kind: 'event',
     };
-    const fakeSignalSourceHit = buildBulkBody(ruleSO, doc);
+    const fakeSignalSourceHit: SignalHitOptionalTimestamp = buildBulkBody(ruleSO, doc);
     // Timestamp will potentially always be different so remove it for the test
-    // @ts-expect-error
     delete fakeSignalSourceHit['@timestamp'];
     const expected: Omit<SignalHit, '@timestamp'> & { someKey: 'someValue' } = {
       someKey: 'someValue',
@@ -339,7 +330,7 @@ describe('buildBulkBody', () => {
             depth: 0,
           },
         ],
-        original_time: '2020-04-20T21:27:45+0000',
+        original_time: '2020-04-20T21:27:45.000Z',
         status: 'open',
         rule: expectedRule(),
         depth: 1,
@@ -351,7 +342,6 @@ describe('buildBulkBody', () => {
   test('bulk body builds "original_signal" if it exists already as a numeric', () => {
     const ruleSO = sampleRuleSO(getQueryRuleParams());
     const sampleDoc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete sampleDoc._source.source;
     const doc = ({
       ...sampleDoc,
@@ -393,7 +383,7 @@ describe('buildBulkBody', () => {
             depth: 0,
           },
         ],
-        original_time: '2020-04-20T21:27:45+0000',
+        original_time: '2020-04-20T21:27:45.000Z',
         status: 'open',
         rule: expectedRule(),
         depth: 1,
@@ -405,7 +395,6 @@ describe('buildBulkBody', () => {
   test('bulk body builds "original_signal" if it exists already as an object', () => {
     const ruleSO = sampleRuleSO(getQueryRuleParams());
     const sampleDoc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete sampleDoc._source.source;
     const doc = ({
       ...sampleDoc,
@@ -447,7 +436,7 @@ describe('buildBulkBody', () => {
             depth: 0,
           },
         ],
-        original_time: '2020-04-20T21:27:45+0000',
+        original_time: '2020-04-20T21:27:45.000Z',
         status: 'open',
         rule: expectedRule(),
         depth: 1,
@@ -466,9 +455,8 @@ describe('buildSignalFromSequence', () => {
     block2._source.new_key = 'new_key_value';
     const blocks = [block1, block2];
     const ruleSO = sampleRuleSO(getQueryRuleParams());
-    const signal = buildSignalFromSequence(blocks, ruleSO);
+    const signal: SignalHitOptionalTimestamp = buildSignalFromSequence(blocks, ruleSO);
     // Timestamp will potentially always be different so remove it for the test
-    // @ts-expect-error
     delete signal['@timestamp'];
     const expected: Omit<SignalHit, '@timestamp'> & { new_key: string } = {
       new_key: 'new_key_value',
@@ -552,9 +540,8 @@ describe('buildSignalFromSequence', () => {
     block2._source['@timestamp'] = '2021-05-20T22:28:46+0000';
     block2._source.someKey = 'someOtherValue';
     const ruleSO = sampleRuleSO(getQueryRuleParams());
-    const signal = buildSignalFromSequence([block1, block2], ruleSO);
+    const signal: SignalHitOptionalTimestamp = buildSignalFromSequence([block1, block2], ruleSO);
     // Timestamp will potentially always be different so remove it for the test
-    // @ts-expect-error
     delete signal['@timestamp'];
     const expected: Omit<SignalHit, '@timestamp'> = {
       event: {
@@ -635,12 +622,11 @@ describe('buildSignalFromSequence', () => {
 describe('buildSignalFromEvent', () => {
   test('builds a basic signal from a single event', () => {
     const ancestor = sampleDocWithAncestors().hits.hits[0];
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete ancestor._source.source;
     const ruleSO = sampleRuleSO(getQueryRuleParams());
-    const signal = buildSignalFromEvent(ancestor, ruleSO, true);
+    const signal: SignalHitOptionalTimestamp = buildSignalFromEvent(ancestor, ruleSO, true);
+
     // Timestamp will potentially always be different so remove it for the test
-    // @ts-expect-error
     delete signal['@timestamp'];
     const expected: Omit<SignalHit, '@timestamp'> & { someKey: 'someValue' } = {
       someKey: 'someValue',
@@ -651,7 +637,7 @@ describe('buildSignalFromEvent', () => {
         _meta: {
           version: SIGNALS_TEMPLATE_VERSION,
         },
-        original_time: '2020-04-20T21:27:45+0000',
+        original_time: '2020-04-20T21:27:45.000Z',
         parent: {
           id: sampleIdGuid,
           rule: '04128c15-0d1b-4716-a4c5-46997ac7f3bd',

x-pack/plugins/security_solution/server/lib/detection_engine/signals/build_event_type_signal.test.ts

@@ -16,7 +16,6 @@ describe('buildEventTypeSignal', () => {
 
   test('it returns the event appended of kind signal if it does not exist', () => {
     const doc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     delete doc._source.event;
     const eventType = buildEventTypeSignal(doc);
     const expected: object = { kind: 'signal' };
@@ -25,7 +24,6 @@ describe('buildEventTypeSignal', () => {
 
   test('it returns the event appended of kind signal if it is an empty object', () => {
     const doc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     doc._source.event = {};
     const eventType = buildEventTypeSignal(doc);
     const expected: object = { kind: 'signal' };
@@ -34,7 +32,6 @@ describe('buildEventTypeSignal', () => {
 
   test('it returns the event with kind signal and other properties if they exist', () => {
     const doc = sampleDocNoSortId();
-    // @ts-expect-error @elastic/elasticsearch _source is optional
     doc._source.event = {
       action: 'socket_opened',
       module: 'system',