[Security Solution] Adds diff algorithm and unit tests for multi-line string fields

package.json

@@ -1098,6 +1098,7 @@
     "monaco-editor": "^0.44.0",
     "monaco-yaml": "^5.1.0",
     "mustache": "^2.3.2",
+    "node-diff3": "^3.1.2",
     "node-fetch": "^2.6.7",
     "node-forge": "^1.3.1",
     "nodemailer": "^6.9.14",

x-pack/plugins/security_solution/server/lib/detection_engine/prebuilt_rules/logic/diff/calculation/algorithms/index.ts

@@ -9,3 +9,4 @@ export { numberDiffAlgorithm } from './number_diff_algorithm';
 export { singleLineStringDiffAlgorithm } from './single_line_string_diff_algorithm';
 export { scalarArrayDiffAlgorithm } from './scalar_array_diff_algorithm';
 export { simpleDiffAlgorithm } from './simple_diff_algorithm';
+export { multiLineStringDiffAlgorithm } from './multi_line_string_diff_algorithm';

x-pack/plugins/security_solution/server/lib/detection_engine/prebuilt_rules/logic/diff/calculation/algorithms/multi_line_string_diff_algorithm.test.ts

@@ -0,0 +1,174 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import type { ThreeVersionsOf } from '../../../../../../../../common/api/detection_engine';
+import {
+  ThreeWayDiffOutcome,
+  ThreeWayMergeOutcome,
+  MissingVersion,
+} from '../../../../../../../../common/api/detection_engine';
+import { multiLineStringDiffAlgorithm } from './multi_line_string_diff_algorithm';
+
+describe('multiLineStringDiffAlgorithm', () => {
+  it('returns current_version as merged output if there is no update - scenario AAA', () => {
+    const mockVersions: ThreeVersionsOf<string> = {
+      base_version: 'My description.\nThis is a second line.',
+      current_version: 'My description.\nThis is a second line.',
+      target_version: 'My description.\nThis is a second line.',
+    };
+
+    const result = multiLineStringDiffAlgorithm(mockVersions);
+
+    expect(result).toEqual(
+      expect.objectContaining({
+        merged_version: mockVersions.current_version,
+        diff_outcome: ThreeWayDiffOutcome.StockValueNoUpdate,
+        merge_outcome: ThreeWayMergeOutcome.Current,
+        has_conflict: false,
+      })
+    );
+  });
+
+  it('returns current_version as merged output if current_version is different and there is no update - scenario ABA', () => {
+    const mockVersions: ThreeVersionsOf<string> = {
+      base_version: 'My description.\nThis is a second line.',
+      current_version: 'My GREAT description.\nThis is a second line.',
+      target_version: 'My description.\nThis is a second line.',
+    };
+
+    const result = multiLineStringDiffAlgorithm(mockVersions);
+
+    expect(result).toEqual(
+      expect.objectContaining({
+        merged_version: mockVersions.current_version,
+        diff_outcome: ThreeWayDiffOutcome.CustomizedValueNoUpdate,
+        merge_outcome: ThreeWayMergeOutcome.Current,
+        has_conflict: false,
+      })
+    );
+  });
+
+  it('returns target_version as merged output if current_version is the same and there is an update - scenario AAB', () => {
+    const mockVersions: ThreeVersionsOf<string> = {
+      base_version: 'My description.\nThis is a second line.',
+      current_version: 'My description.\nThis is a second line.',
+      target_version: 'My GREAT description.\nThis is a second line.',
+    };
+
+    const result = multiLineStringDiffAlgorithm(mockVersions);
+
+    expect(result).toEqual(
+      expect.objectContaining({
+        merged_version: mockVersions.target_version,
+        diff_outcome: ThreeWayDiffOutcome.StockValueCanUpdate,
+        merge_outcome: ThreeWayMergeOutcome.Target,
+        has_conflict: false,
+      })
+    );
+  });
+
+  it('returns current_version as merged output if current version is different but it matches the update - scenario ABB', () => {
+    const mockVersions: ThreeVersionsOf<string> = {
+      base_version: 'My description.\nThis is a second line.',
+      current_version: 'My GREAT description.\nThis is a second line.',
+      target_version: 'My GREAT description.\nThis is a second line.',
+    };
+
+    const result = multiLineStringDiffAlgorithm(mockVersions);
+
+    expect(result).toEqual(
+      expect.objectContaining({
+        merged_version: mockVersions.current_version,
+        diff_outcome: ThreeWayDiffOutcome.CustomizedValueSameUpdate,
+        merge_outcome: ThreeWayMergeOutcome.Current,
+        has_conflict: false,
+      })
+    );
+  });
+
+  describe('if all three versions are different - scenario ABC', () => {
+    it('returns a computated merged version without a conflict if 3 way merge is possible', () => {
+      const mockVersions: ThreeVersionsOf<string> = {
+        base_version: `My description.\f\nThis is a second\u2001 line.\f\nThis is a third line.`,
+        current_version: `My GREAT description.\f\nThis is a second\u2001 line.\f\nThis is a third line.`,
+        target_version: `My description.\f\nThis is a second\u2001 line.\f\nThis is a GREAT line.`,
+      };
+
+      const expectedMergedVersion = `My GREAT description.\f\nThis is a second\u2001 line.\f\nThis is a GREAT line.`;
+
+      const result = multiLineStringDiffAlgorithm(mockVersions);
+
+      expect(result).toEqual(
+        expect.objectContaining({
+          merged_version: expectedMergedVersion,
+          diff_outcome: ThreeWayDiffOutcome.CustomizedValueCanUpdate,
+          merge_outcome: ThreeWayMergeOutcome.Merged,
+          has_conflict: false,
+        })
+      );
+    });
+
+    it('returns the current_version with a conflict if 3 way merge is not possible', () => {
+      const mockVersions: ThreeVersionsOf<string> = {
+        base_version: 'My description.\nThis is a second line.',
+        current_version: 'My GREAT description.\nThis is a third line.',
+        target_version: 'My EXCELLENT description.\nThis is a fourth.',
+      };
+
+      const result = multiLineStringDiffAlgorithm(mockVersions);
+
+      expect(result).toEqual(
+        expect.objectContaining({
+          merged_version: mockVersions.current_version,
+          diff_outcome: ThreeWayDiffOutcome.CustomizedValueCanUpdate,
+          merge_outcome: ThreeWayMergeOutcome.Conflict,
+          has_conflict: true,
+        })
+      );
+    });
+  });
+
+  describe('if base_version is missing', () => {
+    it('returns current_version as merged output if current_version and target_version are the same - scenario -AA', () => {
+      const mockVersions: ThreeVersionsOf<string> = {
+        base_version: MissingVersion,
+        current_version: 'My description.\nThis is a second line.',
+        target_version: 'My description.\nThis is a second line.',
+      };
+
+      const result = multiLineStringDiffAlgorithm(mockVersions);
+
+      expect(result).toEqual(
+        expect.objectContaining({
+          merged_version: mockVersions.current_version,
+          diff_outcome: ThreeWayDiffOutcome.StockValueNoUpdate,
+          merge_outcome: ThreeWayMergeOutcome.Current,
+          has_conflict: false,
+        })
+      );
+    });
+
+    it('returns target_version as merged output if current_version and target_version are different - scenario -AB', () => {
+      const mockVersions: ThreeVersionsOf<string> = {
+        base_version: MissingVersion,
+        current_version: `My GREAT description.\nThis is a second line.`,
+        target_version: `My description.\nThis is a second line, now longer.`,
+      };
+
+      const result = multiLineStringDiffAlgorithm(mockVersions);
+
+      expect(result).toEqual(
+        expect.objectContaining({
+          merged_version: mockVersions.target_version,
+          diff_outcome: ThreeWayDiffOutcome.StockValueCanUpdate,
+          merge_outcome: ThreeWayMergeOutcome.Target,
+          has_conflict: false,
+        })
+      );
+    });
+  });
+});

x-pack/plugins/security_solution/server/lib/detection_engine/prebuilt_rules/logic/diff/calculation/algorithms/multi_line_string_diff_algorithm.ts

@@ -0,0 +1,114 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { merge } from 'node-diff3';
+import { assertUnreachable } from '../../../../../../../../common/utility_types';
+import type {
+  ThreeVersionsOf,
+  ThreeWayDiff,
+} from '../../../../../../../../common/api/detection_engine/prebuilt_rules';
+import {
+  determineDiffOutcome,
+  determineIfValueCanUpdate,
+  ThreeWayDiffOutcome,
+  ThreeWayMergeOutcome,
+  MissingVersion,
+} from '../../../../../../../../common/api/detection_engine/prebuilt_rules';
+
+/**
+ * Diff algorithm used for string fields that contain multiple lines
+ */
+export const multiLineStringDiffAlgorithm = (
+  versions: ThreeVersionsOf<string>
+): ThreeWayDiff<string> => {
+  const {
+    base_version: baseVersion,
+    current_version: currentVersion,
+    target_version: targetVersion,
+  } = versions;
+
+  const diffOutcome = determineDiffOutcome(baseVersion, currentVersion, targetVersion);
+  const valueCanUpdate = determineIfValueCanUpdate(diffOutcome);
+
+  const { mergeOutcome, mergedVersion } = mergeVersions({
+    baseVersion,
+    currentVersion,
+    targetVersion,
+    diffOutcome,
+  });
+
+  return {
+    base_version: baseVersion,
+    current_version: currentVersion,
+    target_version: targetVersion,
+    merged_version: mergedVersion,
+
+    diff_outcome: diffOutcome,
+    merge_outcome: mergeOutcome,
+    has_update: valueCanUpdate,
+    has_conflict: mergeOutcome === ThreeWayMergeOutcome.Conflict,
+  };
+};
+
+interface MergeResult {
+  mergeOutcome: ThreeWayMergeOutcome;
+  mergedVersion: string;
+}
+
+interface MergeArgs {
+  baseVersion: string | MissingVersion;
+  currentVersion: string;
+  targetVersion: string;
+  diffOutcome: ThreeWayDiffOutcome;
+}
+
+const mergeVersions = ({
+  baseVersion,
+  currentVersion,
+  targetVersion,
+  diffOutcome,
+}: MergeArgs): MergeResult => {
+  switch (diffOutcome) {
+    case ThreeWayDiffOutcome.StockValueNoUpdate:
+    case ThreeWayDiffOutcome.CustomizedValueNoUpdate:
+    case ThreeWayDiffOutcome.CustomizedValueSameUpdate: {
+      return {
+        mergeOutcome: ThreeWayMergeOutcome.Current,
+        mergedVersion: currentVersion,
+      };
+    }
+    case ThreeWayDiffOutcome.StockValueCanUpdate: {
+      return {
+        mergeOutcome: ThreeWayMergeOutcome.Target,
+        mergedVersion: targetVersion,
+      };
+    }
+    case ThreeWayDiffOutcome.CustomizedValueCanUpdate: {
+      if (baseVersion === MissingVersion) {
+        return {
+          mergeOutcome: ThreeWayMergeOutcome.Conflict,
+          mergedVersion: currentVersion,
+        };
+      }
+      const mergedVersion = merge(currentVersion, baseVersion, targetVersion, {
+        stringSeparator: /(\S+|\s+)/g, // Retains all whitespace, which we keep to preserve formatting
+      });
+
+      return mergedVersion.conflict
+        ? {
+            mergeOutcome: ThreeWayMergeOutcome.Conflict,
+            mergedVersion: currentVersion,
+          }
+        : {
+            mergeOutcome: ThreeWayMergeOutcome.Merged,
+            mergedVersion: mergedVersion.result.join(''),
+          };
+    }
+    default:
+      return assertUnreachable(diffOutcome);
+  }
+};

yarn.lock

@@ -23734,6 +23734,11 @@ node-cache@^5.1.0:
   dependencies:
     clone "2.x"
 
+node-diff3@^3.1.2:
+  version "3.1.2"
+  resolved "https://registry.yarnpkg.com/node-diff3/-/node-diff3-3.1.2.tgz#49df8d821dc9cbab87bfd6182171d90169613a97"
+  integrity sha512-wUd9TWy059I8mZdH6G3LPNlAEfxDvXtn/RcyFrbqL3v34WlDxn+Mh4HDhOwWuaMk/ROVepe5tTpnGHbve6Db2g==
+
 node-dir@^0.1.10:
   version "0.1.17"
   resolved "https://registry.yarnpkg.com/node-dir/-/node-dir-0.1.17.tgz#5f5665d93351335caabef8f1c554516cf5f1e4e5"
@@ -29191,7 +29196,7 @@ string-replace-loader@^2.2.0:
     loader-utils "^1.2.3"
     schema-utils "^1.0.0"
 
-"string-width-cjs@npm:string-width@^4.2.0", "string-width@^1.0.2 || 2 || 3 || 4", string-width@^4.0.0, string-width@^4.1.0, string-width@^4.2.0, string-width@^4.2.2, string-width@^4.2.3:
+"string-width-cjs@npm:string-width@^4.2.0":
   version "4.2.3"
   resolved "https://registry.yarnpkg.com/string-width/-/string-width-4.2.3.tgz#269c7117d27b05ad2e536830a8ec895ef9c6d010"
   integrity sha512-wKyQRQpjJ0sIp62ErSZdGsjMJWsap5oRNihHhu6G7JVO/9jIB6UyevL+tXuOqrng8j/cxKTWyWUwvSTriiZz/g==
@@ -29209,6 +29214,15 @@ string-width@^1.0.1:
     is-fullwidth-code-point "^1.0.0"
     strip-ansi "^3.0.0"
 
+"string-width@^1.0.2 || 2 || 3 || 4", string-width@^4.0.0, string-width@^4.1.0, string-width@^4.2.0, string-width@^4.2.2, string-width@^4.2.3:
+  version "4.2.3"
+  resolved "https://registry.yarnpkg.com/string-width/-/string-width-4.2.3.tgz#269c7117d27b05ad2e536830a8ec895ef9c6d010"
+  integrity sha512-wKyQRQpjJ0sIp62ErSZdGsjMJWsap5oRNihHhu6G7JVO/9jIB6UyevL+tXuOqrng8j/cxKTWyWUwvSTriiZz/g==
+  dependencies:
+    emoji-regex "^8.0.0"
+    is-fullwidth-code-point "^3.0.0"
+    strip-ansi "^6.0.1"
+
 string-width@^5.0.1, string-width@^5.1.2:
   version "5.1.2"
   resolved "https://registry.yarnpkg.com/string-width/-/string-width-5.1.2.tgz#14f8daec6d81e7221d2a357e668cab73bdbca794"
@@ -29319,7 +29333,7 @@ stringify-object@^3.2.1:
     is-obj "^1.0.1"
     is-regexp "^1.0.0"
 
-"strip-ansi-cjs@npm:strip-ansi@^6.0.1", strip-ansi@^6.0.0, strip-ansi@^6.0.1:
+"strip-ansi-cjs@npm:strip-ansi@^6.0.1":
   version "6.0.1"
   resolved "https://registry.yarnpkg.com/strip-ansi/-/strip-ansi-6.0.1.tgz#9e26c63d30f53443e9489495b2105d37b67a85d9"
   integrity sha512-Y38VPSHcqkFrCpFnQ9vuSXmquuv5oXOKpGeT6aGrr3o3Gc9AlVa6JBfUSOCnbxGGZF+/0ooI7KrPuUSztUdU5A==
@@ -29333,6 +29347,13 @@ strip-ansi@^3.0.0, strip-ansi@^3.0.1:
   dependencies:
     ansi-regex "^2.0.0"
 
+strip-ansi@^6.0.0, strip-ansi@^6.0.1:
+  version "6.0.1"
+  resolved "https://registry.yarnpkg.com/strip-ansi/-/strip-ansi-6.0.1.tgz#9e26c63d30f53443e9489495b2105d37b67a85d9"
+  integrity sha512-Y38VPSHcqkFrCpFnQ9vuSXmquuv5oXOKpGeT6aGrr3o3Gc9AlVa6JBfUSOCnbxGGZF+/0ooI7KrPuUSztUdU5A==
+  dependencies:
+    ansi-regex "^5.0.1"
+
 strip-ansi@^7.0.1, strip-ansi@^7.1.0:
   version "7.1.0"
   resolved "https://registry.yarnpkg.com/strip-ansi/-/strip-ansi-7.1.0.tgz#d5b6568ca689d8561370b0707685d22434faff45"
@@ -32206,7 +32227,7 @@ [email protected]:
   resolved "https://registry.yarnpkg.com/workerpool/-/workerpool-6.2.1.tgz#46fc150c17d826b86a008e5a4508656777e9c343"
   integrity sha512-ILEIE97kDZvF9Wb9f6h5aXK4swSlKGUcOEGiIYb2OOu/IrDU9iwj0fD//SsA6E5ibwJxpEvhullJY4Sl4GcpAw==
 
-"wrap-ansi-cjs@npm:wrap-ansi@^7.0.0", wrap-ansi@^7.0.0:
+"wrap-ansi-cjs@npm:wrap-ansi@^7.0.0":
   version "7.0.0"
   resolved "https://registry.yarnpkg.com/wrap-ansi/-/wrap-ansi-7.0.0.tgz#67e145cff510a6a6984bdf1152911d69d2eb9e43"
   integrity sha512-YVGIj2kamLSTxw6NsZjoBxfSwsn0ycdesmc4p+Q21c5zPuZ1pl+NfxVdxPtdHvmNVOQ6XSYG4AUtyt/Fi7D16Q==
@@ -32232,6 +32253,15 @@ wrap-ansi@^6.2.0:
     string-width "^4.1.0"
     strip-ansi "^6.0.0"
 
+wrap-ansi@^7.0.0:
+  version "7.0.0"
+  resolved "https://registry.yarnpkg.com/wrap-ansi/-/wrap-ansi-7.0.0.tgz#67e145cff510a6a6984bdf1152911d69d2eb9e43"
+  integrity sha512-YVGIj2kamLSTxw6NsZjoBxfSwsn0ycdesmc4p+Q21c5zPuZ1pl+NfxVdxPtdHvmNVOQ6XSYG4AUtyt/Fi7D16Q==
+  dependencies:
+    ansi-styles "^4.0.0"
+    string-width "^4.1.0"
+    strip-ansi "^6.0.0"
+
 wrap-ansi@^8.1.0:
   version "8.1.0"
   resolved "https://registry.yarnpkg.com/wrap-ansi/-/wrap-ansi-8.1.0.tgz#56dc22368ee570face1b49819975d9b9a5ead214"