title: Not able to log model or artifact to Mlflow
body: <p>I have a MLFlow remote server and I am able to log things from rstudio like:</p>
  
  <pre><code>  mlflow_log_param("param1", 5)
    mlflow_log_param("param2", 5)
    mlflow_log_metric("foo", 1)
    mlflow_log_metric("foo", 2)
    mlflow_log_metric("foo", 3)
  </code></pre>
  
  <p>But when I try to log things like:</p>
  
  <pre><code>  writeLines("Hello world!", "output.txt") 
    mlflow_log_artifact("output.txt")
  </code></pre>
  
  <p>I have this error:</p>
  
  <pre><code>2020/04/01 21:45:27 INFO mlflow.store.artifact.cli: Logged artifact from local file output.txt to artifact_path=None
  Root URI: ./mlruns/12/3256cfd3cd1b44b99334040bd5c7c9ee/artifacts
  </code></pre>
  
  <p>And when I try to log a model:</p>
  
  <pre><code> mlflow_log_model(predictor, "model1")
  </code></pre>
  
  <p>I have next error:</p>
  
  <pre><code> 2020/04/01 21:56:44 INFO mlflow.store.artifact.cli: Logged artifact from local dir D:/user/AppData/Local/Temp/RtmpcBwDOP/model1 to artifact_path=model1
      Root URI: ./mlruns/12/07d84e0f252a4248bb2473229297d318/artifacts
      # A tibble: 0 x 0
      Warning message:
      In value[[3L]](cond) :
        Logging model metadata to the tracking server has failed, possibly due to older server version. The model artifacts have been logged successfully. In addition to exporting model artifacts, MLflow clients 1.7.0 and above attempt to record model metadata to the  tracking store. If logging to a mlflow server via REST, consider  upgrading the server version to MLflow 1.7.0 or above.
  </code></pre>
  
  <p>The server is updated and also the client.</p>