django view function that proxys solr instances - usage: url/collection/?q=the-solr-query

views.py

def search_custom( request, collection ):
    """
    Returns unmodified SELECT solr requests to settings_app.COLLECTION_MAPPER solr urls.
    # possible TODO: override max_rows
    """
    ## check that we're only using GET requests
    if request.method != 'GET':
        return HttpResponseNotAllowed(['GET'])
    ## grab request parameter string
    logger.debug( u'request.GET: %s' % request.GET )
    logger.debug( u'request.META: %s' % request.META )
    logger.debug( u"request.META[u'QUERY_STRING']: %s" % request.META[u'QUERY_STRING'] )
    if not request.GET:
        output = json.dumps(
            { u'docs': settings_app.DOCUMENTATION_URL,
              u'hint': u'No solr parameters found.',
              u'status': u'400 / Bad Request' }, indent=2, sort_keys=True )
        return HttpResponseBadRequest( output, content_type=u'application/json; charset=utf-8' )
    params_string = request.META[u'QUERY_STRING'].decode(u'utf-8', u'replace')
    assert type(params_string) == unicode, type(params_string)
    ## construct solr url
    try:
        base_solr_url = settings_app.COLLECTION_MAPPER[ collection ]
        logger.debug( u'base_solr_url: ' + base_solr_url )
        assert base_solr_url[-8:] == u'/select/', base_solr_url[-8:]
    except Exception as e:
        logger.debug( u'Exception: ' + repr(e).decode(u'utf-8', u'replace') )
        output = json.dumps(
            { u'docs': settings_app.DOCUMENTATION_URL,
              u'hint': u'Invalid solr instance.',
              u'status': u'400 / Bad Request' }, indent=2, sort_keys=True )
        return HttpResponseBadRequest( output, content_type=u'application/json; charset=utf-8' )
    url = u'%s?%s' % ( base_solr_url, params_string )
    logger.debug( u'Trying url: ' + url )
    ## hit solr
    try:
        resp = requests.get( url )
    except Exception as e:
        logger.error( u'Error querying solr: ' + str(e) )
        logger.error( u'Solr status code was: ' + str(resp.status_code) )
        logger.error( u'Solr data was: ' + resp.content )
        return HttpResponseServerError( u'Internal Server error.' )
    if resp.status_code == 400 and settings_app.PARSE_ERROR in resp.content:
        logger.error( u'Got parse exception: ' + resp.content )
        return HttpResponseBadRequest( u'Error parsing query. Please check the format.' )
    ## determine preferred response format
    format_pref = request.GET.get( u'wt', None )
    if format_pref:
        if format_pref == u'json':
            content_type = u'application/json; charset=utf-8'
        elif format_pref == u'xml':
            content_type = u'text/xml; charset=utf-8'
        else:
            content_type = u'text/plain; charset=utf-8'
    else:
        content_type = u'text/xml; charset=utf-8'  # solr default
    ## build response
    output = resp.content.decode( u'utf-8', u'replace' )
    assert type(output) == unicode
    callback = request.GET.get( u'callback', None )
    if callback:
      assert type(callback) == unicode
      output = u'%s(%s)' % ( callback, output )
      content_type = u'application/json; charset=utf-8'  # overrides above determination
    return HttpResponse( output, content_type=content_type )
    # end def search_custom()