[Bug] "similarity" parameter of GET /api/alert/<ID> doesnt work

[Zeecka]

Request Type

Bug

Work Environment

Question	Answer
TheHive version / git hash	4.1.4-1 (docker image thehiveproject/thehive4:latest)
Package Type	Docker
Index type	Elasticsearch

Problem Description

similarity GET parameter of /api/alert/<ID> route is broken.
According to documentation, /api/alert/:alertId provides a parameter named similarity which can be set to 1 to fill the similarCases field of the output (ie. /api/alert/~20672?similarity=1). However, the server answer with a 404 error: {"type":"NotFoundError","message":"Alert not found"}. Note that the alert exist and the error disapear when similarity is set to 0 or not set.

Steps to Reproduce

1. Create 2 alerts with same artifacts
2. Transform one of the alert to a Case
3. Query the API with the id of the other alert: /api/alert/<ID>?similarity=1

Possible Solutions

Fix with the expected behavior

[Zeecka]

Duplicate of #1981