How to run BrowserMob Proxy with RobotFramework and Capture HAR files

Question

I have written this code in robotframework

${proxy}=            |  Evaluate |  sys.modules['selenium.webdriver'].Proxy()   sys, selenium.webdriver | 
${proxy.http_proxy}= |  Set Variable           |    127.0.0.1:8080   | 
Create Webdriver     |  Firefox proxy=${proxy} |     
Go To                |  http://www.knowledgefarm.in/tst/a.html | 

And I am running BrowserMob proxy from command line like this:

browsermob-proxy.bat --address 127.0.0.1 --port 8080

Now, when i run robotframework, it open the browser and simple give this message on page.

HTTP ERROR: 404

Problem accessing /tst/a.html. Reason:
Not Found
Powered by Jetty:// 

Two questions:

1. why my pages are not loaded. (it works if I remove proxy setting)

2. After the workaround, how do I specify to generate HAR file and how should I specify the location of HAR file

Answer 1

The above code does not actually start a proxy. To start a proxy, you need to run these commands.

Create     | http context    |  localhost:8080 |    http    
Post       | /proxy     
${json} | Get Response Body     
${port}    | Get Json Value  | ${json} | /port
${proxy}=  | Evaluate           | sys.modules['selenium.webdriver'].Proxy()  | sys,selenium.webdriver
${proxy.http_proxy}= |  Set Variable |  127.0.0.1:${port}   
Create Webdriver     | Firefox   | proxy=${proxy}   
Go To      | ${LOGIN URL}   

Set Request Body | pageRef=LOGIN&captureContent=false&captureHeaders=true       
PUT        | /proxy/${port}/har 
${json} | HttpLibrary.HTTP.Get Response Body        
OperatingSystem.Create File | D:\\myfile.har  | ${json}