Data for Freifunk Map, Graph and Node List

ffmap-backend gathers information on the batman network by invoking :

• batctl (might require root),
• alfred-json and
• batadv-vis

The output will be written to a directory (-d output).

Run backend.py --help for a quick overview of all available options.

For the script's regular execution add the following to the crontab:

* * * * * backend.py -d /path/to/output -a /path/to/aliases.json --vpn ae:7f:58:7d:6c:2a d2:d0:93:63:f7:da

Dependencies

• Python 3
• Python 3 Package Networkx (on debian wheezy: pip-3.2 install networkx)
• alfred-json
• rrdtool (if run with --with-rrd)

Running as unprivileged user

Some information collected by ffmap-backend requires access to specific system resources.

Make sure the user you are running this under is part of the group that owns the alfred socket, so alfred-json can access the alfred daemon.

# ls -al /var/run/alfred.sock
srw-rw---- 1 root alfred 0 Mar 19 22:00 /var/run/alfred.sock=
# adduser map alfred
Adding user `map' to group `alfred' ...
Adding user map to group alfred
Done.
$ groups
map alfred

Running batctl requires passwordless sudo access, because it needs to access the debugfs to retrive the gateway list.

# echo 'map ALL = NOPASSWD: /usr/sbin/batctl' | tee /etc/sudoers.d/map
map ALL = NOPASSWD: /usr/sbin/batctl
# chmod 0440 /etc/sudoers.d/map

That should be everything. The script automatically detects if it is run in unprivileged mode and will prefix sudo where necessary.

Data format

nodes.json

{ 'nodes': {
    node_id: { 'flags': { flags },
               'firstseen': isoformat,
               'lastseen': isoformat,
               'nodeinfo': {...},         # copied from alfred type 158
               'statistics': {
                  'uptime': double,       # seconds
                  'memory_usage': double, # 0..1
                  'clients': double,
                  'rootfs_usage': double, # 0..1
                  'loadavg': double,
                  'gateway': mac
                }
             },
    ...
  }
  'timestamp': isoformat
}

flags (bool)

• online
• gateway

Old data format

If you want to still use the old ffmap-d3 front end, you can use the file ffmap-d3.jq to convert the new output to the old one:

jq -n -f ffmap-d3.jq \
    --argfile nodes nodedb/nodes.json \
    --argfile graph nodedb/graph.json \
    > nodedb/ffmap-d3.json

Then point your ffmap-d3 instance to the ffmap-d3.json file.

Removing owner information

If you'd like to redact information about the node owner from nodes.json, you may use the parameter anonymize, e.g.:

./backend.py --anonymize

This will remove owner information from nodes.json before copying the data to your webserver.

Set RRD graph time ranges

If you'd like to extend your RRD graphs time range you can use the paramters rrd-time-node and rrd-time-global, e.g.:

./backend.py --rrd-time-node 7d --rrd-time-global 14d

Aliases Online

To add aliases online with statistic you can use the parameter online-aliases, e.g.:

./backend.py --online-aliases aliases.json

Example online aliases JSON file:

[
  {
    "node_id": "rathaus",
    "hostname": "Rathaus",
    "location": {
      "longitude": 8.6700260,
      "latitude": 52.1160820
    },
    "statistics": {
      "clients": 123
    },
    "network": {
      "mesh": {
        "bat0": {
          "interfaces": {
            "tunnel": [
              "00:25:86:e6:f1:c0"
            ]
          }
        }
      }
    }
  }
]