A script to create a HAR file out of a mitmproxy's dump file

harwriter.py

#!/usr/bin/env python

import binascii, sys, json
import version, tnetstring, flow
from datetime import datetime


def create_har(flows):
    return {
        "log":{
            "version": "1.2",
            "creator": {"name":version.NAME,"version":version.VERSION},
            "entries": [format_flow(fl) for fl in flows]
        }
    }

def format_flow(fl):
    result = {
        "startedDateTime":format_timestamp(fl),
        "time":flow_total_duration(fl),
        "request":format_request(fl.request),
        "response":format_response(fl.response),
        "cache":{}, # mitmproxy is not cache-aware
        "timings":format_flow_timings(fl),
        "connection":str(fl.request.client_conn)
    }
    return result

def format_request(request):
    result = {
        'method':request.method,
        'url':request.get_url(),
        'httpVersion':"HTTP/%d.%d"%request.httpversion,
        'cookies':format_request_cookies(request.get_cookies()),
        'headers':format_headers(request.headers),
        'queryString':format_query_parameters(request.get_query()),
        'headersSize':request.get_header_size(),
    }

    if request.content:
        result['postData'] = format_request_data(request)
        result['bodySize'] = request.get_transmitted_size()
    else:
        result['bodySize'] = -1

    return result

def format_response(response):
    result = {
        'status':response.code,
        'statusText':response.msg,
        'httpVersion':"HTTP/%d.%d"%(response.httpversion[0],response.httpversion[1]),
        'cookies':format_response_cookies(response.get_cookies()),
        'headers':format_headers(response.headers),
        'content':format_response_data(response),
        'redirectURL':format_redirect_url(response),
        'headersSize':response.get_header_size(),
        'bodySize':response.get_transmitted_size(),
    }
    return result

def format_timestamp(fl):
    # currently we don't keep the dns or tcp timings, so the earliest
    # timestamps for us to use is the request send time.
    timestamp = fl.request.timestamp_start
    return datetime.utcfromtimestamp(timestamp).isoformat()+'+00:00'

def round_timestamp(ts):
    return int(ts*1000)

def flow_total_duration(fl):
    # FIXME: what if there's no response?
    return round_timestamp(fl.response.timestamp_end)-round_timestamp(fl.request.timestamp_start)

def format_flow_timings(fl):
    return {
        # event though the documentation says we should not add 'blocked','dns' and 'connect',
        # the online viewer will not without those
        'blocked':-1,
        'dns':-1,
        'connect':-1,
        'send':round_timestamp(fl.request.timestamp_end)-round_timestamp(fl.request.timestamp_start),
        'wait':round_timestamp(fl.response.timestamp_start)-round_timestamp(fl.request.timestamp_end),
        'receive':round_timestamp(fl.response.timestamp_end)-round_timestamp(fl.response.timestamp_start),
    }


def format_headers(headers):
    if not headers:
        return []
    return [{"name":key, "value":value} for key, value in headers.items()]

def format_query_parameters(query_parameters):
    if not query_parameters:
        return []
    return [{"name":key, "value":value} for key, value in query_parameters.items()]

def format_request_cookies(cookies):
    if not cookies:
        return []
    return [{"name":key, "value":value} for key, (value, parameters) in cookies.items()]

def format_response_cookies(cookies):
    if not cookies:
        return []
    result = []
    for key, (value, parameters) in cookies.items():
        cookie = {"name":key, "value":value}
        for param in ("path", "domain", "expires"):
            if param in parameters:
                cookie[param] = parameters[param]
        if "httponly" in parameters:
            cookie["httpOnly"]=True
        if "secure" in parameters:
            cookie["secure"]=True
        result.append(cookie)
    return result

def format_request_data(request):
    assert(request)
    assert(request.content)
    urlencoded_parameters = request.get_form_urlencoded()
    if urlencoded_parameters:
        return {
            "mimeType":format_content_type(request.get_content_type()),
            "params":format_urlencoded_parameters(urlencoded_parameters),
            "text":"",
        }
    elif request.content:
        return {
            "mimeType":format_content_type(request.get_content_type()),
            "params":[],
            "text":request.content
        }

def format_content_type(content_type):
    return content_type or ""

def format_urlencoded_parameters(urlencoded_parameters):
    if not urlencoded_parameters:
        return []
    return [{"name":key, "value":value} for key,value in urlencoded_parameters.items()]

def format_response_data(response):
    content_type = format_content_type(response.get_content_type())
    if response.content:
        # we always use base64, avoiding the need to check that the content is in utf8.
        # we use strip to remove the newline the base64 encoding adds
        data = binascii.b2a_base64(response.get_decoded_content()).strip()
        return {
            "size":len(data),
            "mimeType":content_type,
            "text":data,
            "encoding":"base64",
        }
    else:
        return {
            "mimeType":content_type,
            "size":0
        }

def format_redirect_url(response):
    return response.headers.get_first("location", "")



if __name__ == '__main__':
    if len(sys.argv)<3:
        print "usage: %s input_dump_file output_har_file"%sys.argv[0]
        sys.exit(0)
    data = open(sys.argv[1]).read()
    reminder = data
    flows = []
    discarded = 0

    while reminder:
        obj, reminder = tnetstring.pop(reminder)
        f = flow.Flow._from_state(obj)
        if (f.response):
            flows.append(f)
        else:
            discarded+=1
    if discarded:
        print "discarding %d flows without valid responses"%discarded

    har = create_har(flows)
    json.dump(har, open(sys.argv[2],'w'))

Hi Rouli,
I am converting the dump from mitmdump (version -0.11.3) and getting the following error , the command im using is > python harwriter.py abd.log abc.har.
Error:
Traceback (most recent call last):
File "harwriter.py", line 178, in
f = flow.Flow._from_state(obj)
AttributeError: 'module' object has no attribute 'Flow'

Please let know how to solve this issue

mitmproxy now provides an example on how to do this:
See http://mitmproxy.org/doc/features/clientreplay.html on how to replay from a stored transaction and https://github.com/mitmproxy/mitmproxy/blob/master/examples/har_extractor.py as an example on how to actually extract data into a har file.

I've been working on this for hours and still can't find an example of how to actually use that script. Is there any documentation that just says "do this to convert the flow to a HAR?"

for anyone else searching for har_extractor.py usage: mitmproxy/mitmproxy#986

FWIW, the latest seems to be har_dump: mitmproxy/har_dump.py at master · mitmproxy/mitmproxy