Add GqlStatus Finder Functions (#1314)

Author: MaxAake

packages/core/src/error.ts

@@ -150,6 +150,34 @@ class GQLError extends Error {
     this.name = 'GQLError'
   }
 
+  /**
+   * Returns whether a given GqlStatus code can be found in the cause chain of the error (including the error itself).
+   *
+   * @param {string} gqlStatus the GqlStatus code to find
+   * @returns {boolean}
+   */
+  containsGqlCause (gqlStatus: string): boolean {
+    return this.findByGqlStatus(gqlStatus) !== undefined
+  }
+
+  /**
+   * Returns the first error in the cause chain (including the error itself) with a given GqlStatus code.
+   * Returns undefined if the GqlStatus code is not present anywhere in the chain.
+   *
+   * @param {string} gqlStatus the GqlStatus code to find
+   * @returns {GQLError | Neo4jError | undefined}
+   */
+  findByGqlStatus (gqlStatus: string): GQLError | Neo4jError | undefined {
+    if (this.gqlStatus === gqlStatus) {
+      return this
+    }
+    if (this.cause !== undefined && (this.cause instanceof GQLError || this.cause instanceof Neo4jError)) {
+      return this.cause.findByGqlStatus(gqlStatus)
+    }
+
+    return undefined
+  }
+
   /**
    * The json string representation of the diagnostic record.
    * The goal of this method is provide a serialized object for human inspection.

packages/core/test/error.test.ts

@@ -16,6 +16,7 @@
  */
 import {
   Neo4jError,
+  GQLError,
   isRetryableError,
   newError,
   newGQLError,
@@ -201,8 +202,41 @@ describe('Neo4jError', () => {
       expect(Neo4jError.isRetryable(error)).toBe(false)
     })
   })
+
+  describe('.containsGqlCause()', () => {
+    it.each([
+      [createNestedErrors(0), 'cause0', false],
+      [createNestedErrors(0), 'root', true],
+      [createNestedErrors(10), 'cause8', true],
+      [createNestedErrors(10), 'cause11', false]
+    ])('should correctly identify if GQLStatus is present in cause chain', (error, status, expectedResult) => {
+      expect(error.containsGqlCause(status)).toBe(expectedResult)
+    })
+  })
+
+  describe('.findByGqlStatus()', () => {
+    it.each([
+      [createNestedErrors(0), 'cause0', undefined],
+      [createNestedErrors(0), 'root', 'root'],
+      [createNestedErrors(10), 'cause8', '8cause'],
+      [createNestedErrors(10), 'cause11', undefined]
+    ])('should correctly find error in cause chain', (error, status, expectedMessage) => {
+      expect(error.findByGqlStatus(status)?.message).toBe(expectedMessage)
+    })
+  })
 })
 
+function createNestedErrors (causes: number): Neo4jError {
+  const error = new Neo4jError('root', '', 'root', '')
+  let current: Neo4jError | GQLError = error
+  for (let i = 0; i < causes; i++) {
+    const cause = new GQLError(i.toString() + 'cause', 'cause' + i.toString(), '')
+    current.cause = cause
+    current = cause
+  }
+  return error
+}
+
 function getRetryableErrorsFixture (): Array<[Neo4jError]> {
   return getRetryableCodes().map(code => [newError('message', code)])
 }