[BUG][Java][okhttp-gson] RuntimeException with undefined authentication method

Created by: sebastien-rosset

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Description

A RuntimeException may be thrown when invoking an API, provided the OAS document defines more than one security scheme and the client creates the ApiClient class by invoking a constructor with arguments.

Exception in thread "main" java.lang.RuntimeException: Authentication undefined: cookieAuth
	at ....client.ApiClient.updateParamsForAuth(ApiClient.java:1294)
	at ....client.ApiClient.buildRequest(ApiClient.java:1138)
	at ....client.ApiClient.buildCall(ApiClient.java:1108)
	at .....client.api.AaaApi.getXYZCall(AaaApi.java:143)

This happens because:

1. the Java okhttp-gson mustache template generates the following constructors:

public ApiClient()
public ApiClient(String clientId)
public ApiClient(String clientId, Map<String, String> parameters)
public ApiClient(String clientId, String clientSecret, Map<String, String> parameters)

2. But only the basic constructor ApiClient() initializes all authentication methods.

   authentications.put("cookieAuth", new ApiKeyAuth("cookie", "X-My-Token")); authentications.put("oAuth2", new OAuth());

For example, the constructor ApiClient(String clientId, String clientSecret, Map<String, String> parameters) initializes the OAuth2 authentication parameters but not the other ones.

3. When invoking an API, the ApiClient.updateParamsForAuth() expects all authentication parameters to be initialized.

openapi-generator version

master Marcch 4th 2020

OpenAPI declaration file content or url

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