Sending a POST request using Balkan's requests lib with data and files (Robot Framework)
<p>I'm trying to send a request (post) using Balkan's requests library from test case written in Robot Framework <a href="http://bulkan.github.io/robotframework-requests/#Post" rel="nofollow">http://bulkan.github.io/robotframework-requests/#Post</a> with two parameters as a data and a file. Unfortunatelly, all the time I have the same error like described below.</p>

<p>My Test Case:</p>

<pre><code>X_T_Should Upload File Correctly And Get HTTP 200
    Send Default File To SUT And Return Response

*** Keywords ***
Send Default File To SUT And Return Response
    [Arguments]    ${user_login}=${USER_LOGIN}    ${user_password}=${USER_PASSWORD}
    ${url}=    Get URL
    ${auth}=    Create List    ${user_login}    ${user_password}
    Create Session    rm    ${url}    auth=${auth}
    &amp;{headers}=    Create Dictionary    Content-Type=application/x-www-form-urlencoded
    &amp;{data}=    Create Dictionary    name=file    filename=${DEFAULT_FILE_NAME}
    ${file_data}=    Get Binary File    ${CURDIR}${/}Resources${/}${DEFAULT_FILE_NAME}
    &amp;{files}=    Create Dictionary    file=${file_data}
    ${resp}=    Post Request    rm    ${UPLOAD_URI}    files=${files}    data=${data}    headers=${headers}
    Delete All Sessions
</code></pre>

<p>Error (from Robot Framework):</p>

<pre><code>20160525 09:47:10.645 :  FAIL : ValueError: Data must not be a string.
</code></pre>

<p>The problem is with the keyword Post Request. When I do not set an argument files or data that everything is well but if I set both args. that I see these strange error. </p>

<p>It is a bug in library?</p>