CgiCorrelator

class sitchlib.CgiCorrelator(feed_dir, cgi_whitelist, mcc_list, device_id)[source]

The CgiCorrelator compares CGI addressing against the OpenCellID DB.

The feed data is put in place by the FeedManager class, prior to instantiating the CgiCorrelator.

classmethod bts_from_channel(channel)[source]

Create a simplified representation of BTS metadata.

Parameters:channel (dict) –
Returns:Contains MCC, MNC, LAC, and cellid
Return type:dict
classmethod build_chan_here(channel, state)[source]

Build geo information for channel, to aid in geo correlation.

Parameters:
  • channel (dict) – Channel metadata
  • state (dict) – Geo-json representing the current location of the sensor
Returns:

Original channel structure, with the current sensor location

embedded.
Return type:

dict
classmethod cell_matches(cell, mcc, mnc, lac, cellid)[source]

Compare cell metadata against mcc, mnc, lac, cellid.

classmethod cgi_whitelist_message(cgi_wl)[source]

Format and return the CGI whitelist initialization message.

Parameters:cgi_wl (list) – CGI whitelist
Returns:Formatted message
Return type:str
classmethod channel_in_feed_db(channel)[source]

Return True if channel geo metadata is complete.

classmethod channel_out_of_range(channel)[source]

Check to see if sensor is out of range for CGI.

Parameters:channel (dict) – Channel metadata
Returns:True if the sensor is in range of the detected CGI
Return type:bool
check_channel_against_feed(channel)[source]

Determine whether or not to fire an alert for CGI presence in feed.

Parameters:channel (dict) – Channel metadata
Returns:
Empty if there is no alert, a two-item tuple if an alert
is generated.
Return type:tuple
check_channel_range(channel)[source]

Check to see if the detected CGI is in range.

Parameters:channel (dict) – Channel metadata, enriched with feed info.
Returns:
Empry if no alert is generated. A two-item tuple if an
alert condition is detected.
Return type:tuple
check_scan_document(scan_document)[source]

Check to see if there are no in-LAI neighbors for channel 0

classmethod convert_float_targets(channel)[source]

Convert string values for rxq and rxl to floating point.

classmethod convert_hex_targets(channel)[source]

Convert lac and cellid from hex to decimal.

correlate(scan_bolus)[source]

Entrypoint for the CGI correlation component.

Parameters:scan_bolus (tuple) – scan_bolus[0] contains the scan type. If the type is ‘gps’, it will set the correlator’s geo location. For other scan types, we expect them to look like gsm_modem_channel events, and they are compared against the feed database as well as state history, tracking things like the current active cell’s CGI.
Returns:
Returns a list of tuples, representing alerts. If no alerts
fire, the list will be empty.
Return type:list
feed_comparison(channel)[source]

Compare channel metadata against the feed DB.

This function wraps a few checks against the feed DB. It first checks
if the bts is in the feed DB. Next, it checks that the sensor is within range of the BTS in the feed DB. Finally, if it’s the primary channel, it checks to see if the primary BTS has changed.
Parameters:channel (dict) – Channel, enriched with geo information
Returns:
If alarms are generated, they’ll be returned in a list of
tuples. Otherwise, an empty list comes back.
Return type:list
classmethod get_cell_by_id(scan_document, cell_no)[source]

Get cell from doc by ID

classmethod get_cgi_int(channel)[source]

Attempt to create an integer representation of CGI.

get_feed_info(mcc, mnc, lac, cellid)[source]

Check CGI against cache, then against the feed DB.

Parameters:
  • mcc (str) – Mobile Country Code
  • mnc (str) – Mobile Network Code
  • lac (str) – Location Area Code
  • cellid (str) – Cell ID
Returns:

Dictionary containing feed information for CGI
Return type:

dict
get_feed_info_from_db(mcc, mnc, lac, cellid)[source]

Interrogate DB for CGI information.

Parameters:
  • (str) – Mobile Country Code
  • mnc (str) – Mobile Network Code
  • lac (str) – Location Area Code
  • cellid (str) – Cell ID
Returns:

Dictionary containing feed information for CGI. If no

information exists, the feed geo information will be zeroed out…
Return type:

dict
classmethod make_bts_friendly(bts_struct)[source]

Create a human-friendly representation of CGI.

Parameters:bts_struct (dict) – Simple structure containing CGI components.
Returns:
String reperesentation of CGI, with items being
colon-separated.
Return type:str
classmethod normalize_feed_info_for_cache(feed_item)[source]

Normalize field keys for the feed cache.

classmethod primary_bts_changed(prior_bts, channel, cgi_whitelist)[source]

Create alarms if primary BTS metadats changed.

Parameters:
  • prior_bts (str) – Current primary BTS
  • channel (dict) – Channel metadata
  • cgi_whitelist – Whitelist of CGIs to NOT alert on
Returns:

True if the primary BTS has changed and the new BTS in not

on the whitelist. False otherwise.
Return type:

bool
process_cell_zero(channel)[source]

Process channel zero.

Parameters:channel (dict) – Channel metadata.
Returns:
Empry if there is no alert, a two-item tuple if an alert
condition is detected.
Return type:tuple
classmethod should_skip_feed(channel)[source]

Examine channel info to determine if feed comparison should happen.

Parameters:channel (dict) – Channel information.
Returns:True if channel information is complete, False if not.
Return type:bool