fix(elasticSearch): use more precise matching for query filters

Signed-off-by: Phil Kuang <pkuang@factset.com>

.changeset/search-eight-hounds-worry.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-search-backend-module-elasticsearch': patch
+---
+
+Use more precise matching for query filters

plugins/search-backend-module-elasticsearch/src/engines/ElasticSearchSearchEngine.test.ts

@@ -153,7 +153,7 @@ describe('ElasticSearchSearchEngine', () => {
             },
             filter: {
               match: {
-                kind: 'testKind',
+                'kind.keyword': 'testKind',
               },
             },
           },
@@ -204,7 +204,12 @@ describe('ElasticSearchSearchEngine', () => {
       const actualTranslatedQuery = translatorUnderTest({
         types: ['indexName'],
         term: 'testTerm',
-        filters: { kind: 'testKind', namespace: 'testNameSpace' },
+        filters: {
+          kind: 'testKind',
+          namespace: 'testNameSpace',
+          foo: 123,
+          bar: true,
+        },
       }) as ConcreteElasticSearchQuery;
 
       expect(actualTranslatedQuery).toMatchObject({
@@ -228,12 +233,22 @@ describe('ElasticSearchSearchEngine', () => {
             filter: [
               {
                 match: {
-                  kind: 'testKind',
+                  'kind.keyword': 'testKind',
                 },
               },
               {
                 match: {
-                  namespace: 'testNameSpace',
+                  'namespace.keyword': 'testNameSpace',
+                },
+              },
+              {
+                match: {
+                  foo: '123',
+                },
+              },
+              {
+                match: {
+                  bar: 'true',
                 },
               },
             ],

plugins/search-backend-module-elasticsearch/src/engines/ElasticSearchSearchEngine.ts

@@ -168,7 +168,9 @@ export class ElasticSearchSearchEngine implements SearchEngine {
       .filter(([_, value]) => Boolean(value))
       .map(([key, value]: [key: string, value: any]) => {
         if (['string', 'number', 'boolean'].includes(typeof value)) {
-          return esb.matchQuery(key, value.toString());
+          // Use exact matching for string datatype fields
+          const keyword = typeof value === 'string' ? `${key}.keyword` : key;
+          return esb.matchQuery(keyword, value.toString());
         }
         if (Array.isArray(value)) {
           return esb