add postgres dialect support for homelab migration

test/server/utils/sqlDialectHelpers.test.js

@@ -0,0 +1,58 @@
+const { expect } = require('chai')
+
+const {
+  booleanLiteral,
+  noCaseSortExpression,
+  coalesceFunctionName,
+  jsonArrayContainsAny,
+  jsonArrayContainsValue,
+  jsonArrayExpand,
+  jsonPathText,
+  jsonPathNumber
+} = require('../../../server/utils/sqlDialectHelpers')
+
+const sqlite = {
+  getDialect: () => 'sqlite'
+}
+
+const postgres = {
+  getDialect: () => 'postgres'
+}
+
+describe('sqlDialectHelpers', () => {
+  it('should return sqlite and postgres boolean literals', () => {
+    expect(booleanLiteral(true, sqlite)).to.equal('1')
+    expect(booleanLiteral(false, sqlite)).to.equal('0')
+    expect(booleanLiteral(true, postgres)).to.equal('TRUE')
+    expect(booleanLiteral(false, postgres)).to.equal('FALSE')
+  })
+
+  it('should generate case-insensitive sort expressions', () => {
+    expect(noCaseSortExpression('name', sqlite)).to.equal('name COLLATE NOCASE')
+    expect(noCaseSortExpression('name', postgres)).to.equal('LOWER(name)')
+  })
+
+  it('should choose the correct null-coalescing function name', () => {
+    expect(coalesceFunctionName(sqlite)).to.equal('IFNULL')
+    expect(coalesceFunctionName(postgres)).to.equal('COALESCE')
+  })
+
+  it('should generate array membership count queries per dialect', () => {
+    expect(jsonArrayContainsAny('tags', 'selectedTags', sqlite)).to.equal('(SELECT count(*) FROM json_each(tags) WHERE json_valid(tags) AND json_each.value IN (:selectedTags))')
+    expect(jsonArrayContainsAny('tags', 'selectedTags', postgres)).to.equal("(SELECT count(*) FROM jsonb_array_elements_text(COALESCE(tags::jsonb, '[]'::jsonb)) AS json_each(value) WHERE json_each.value IN (:selectedTags))")
+
+    expect(jsonArrayContainsValue('tags', 'tag', sqlite)).to.equal('(SELECT count(*) FROM json_each(tags) WHERE json_valid(tags) AND json_each.value = :tag)')
+    expect(jsonArrayContainsValue('tags', 'tag', postgres)).to.equal("(SELECT count(*) FROM jsonb_array_elements_text(COALESCE(tags::jsonb, '[]'::jsonb)) AS json_each(value) WHERE json_each.value = :tag)")
+  })
+
+  it('should generate json array expansion and path extraction by dialect', () => {
+    expect(jsonArrayExpand('books.tags', sqlite)).to.equal('json_each(books.tags)')
+    expect(jsonArrayExpand('books.tags', postgres)).to.equal("jsonb_array_elements_text(COALESCE(books.tags::jsonb, '[]'::jsonb)) AS json_each(value)")
+
+    expect(jsonPathText('payload', ['metadata', 'filename'], sqlite)).to.equal("json_extract(payload, '$.metadata.filename')")
+    expect(jsonPathText('payload', ['metadata', 'filename'], postgres)).to.equal("payload::jsonb #>> '{metadata,filename}'")
+
+    expect(jsonPathNumber('payload', ['duration'], sqlite)).to.equal("json_extract(payload, '$.duration')")
+    expect(jsonPathNumber('payload', ['duration'], postgres)).to.equal("NULLIF(payload::jsonb #>> '{duration}', '')::double precision")
+  })
+})