I'm working on extenral service that will use REST API. The service will make a login to Salesgforce every day and will run REST queries. From this article, it seems that I need to use OAuth2 - username&password flow as my authentication method:
Much like the SOAP APIs offered by Force.com, the REST API requires users to be authenticated before accessing the data or functionality within the Force.com organization. While it is possible to reuse the SOAP-based authentication token for REST service calls, a better option is to embrace one of the OAuth 2.0 authentication flows. In the scenario below, you will use the username-password OAuth authentication flow to pass credentials to Force.com and acquire a valid session token.
For OAuth 2.0, there is a need to create a connected App and insert more credentials parameters to my service (client key, client secret). So, before implement this solution, I want to understand why OAuth 2.0 is a better option.