@GET
  @Path("{sourceId}")
  @Produces("text/plain")
  @ApiOperation(value = "Get user authentication source", response = UserAuthenticationSourceResponse.UserAuthenticationSourceResponseSwagger.class)
  @ApiImplicitParams({
      @ApiImplicitParam(name = QUERY_FIELDS, value = QUERY_FILTER_DESCRIPTION, dataType = DATA_TYPE_STRING, paramType = PARAM_TYPE_QUERY, defaultValue = AUTHENTICATION_SOURCE_RESOURCE_CATEGORY + "/*"),
  })
  @ApiResponses({
      @ApiResponse(code = HttpStatus.SC_OK, message = MSG_SUCCESSFUL_OPERATION),
      @ApiResponse(code = HttpStatus.SC_NOT_FOUND, message = MSG_RESOURCE_NOT_FOUND),
      @ApiResponse(code = HttpStatus.SC_UNAUTHORIZED, message = MSG_NOT_AUTHENTICATED),
      @ApiResponse(code = HttpStatus.SC_FORBIDDEN, message = MSG_PERMISSION_DENIED),
      @ApiResponse(code = HttpStatus.SC_INTERNAL_SERVER_ERROR, message = MSG_SERVER_ERROR),
  })
  public Response getAuthenticationSource(@Context HttpHeaders headers, @Context UriInfo ui,
                                          @ApiParam(value = "user name", required = true) @PathParam("userName") String userName,
                                          @ApiParam(value = "source id", required = true) @PathParam("sourceId") String sourceId) {
    return handleRequest(headers, null, ui, Request.Type.GET, createResource(userName, sourceId));
  }
Handles: GET /users/{userName}/sources/{sourceID}
Get a specific authentication source.

@param headers  http headers
@param ui       uri info
@param userName user name
@param sourceId authentication source id
@return authentication source instance representation
ambari-server/src/main/java/org/apache/ambari/server/api/services/users/UserAuthenticationSourceService.java