import json

class DB(object):
    '''
    db.add({timestamp: time.time(),
    agent: 'tizio',
    action: 'search',
    target: 'tasse'
    })
    db.add({timestamp: time.time(),
    agent: 'tizio',
    action: 'wall',
    seen: [
    {user: 'zerogreggi', msg: 'ho le pecore'},
    {user: 'caio', msg: 'ci faccio il formaggio'},
    ]
    })
    searches = [s for s in db.all() if s['action'] == 'wall']
    '''
    def __init__(self, fname):
        self.fname = fname

    def add(self, doc):
        with open(self.fname, 'a') as buf:
            buf.write(json.dumps(doc))
            buf.write('\n')

    def all(self):
        with open(self.fname) as buf:
            for line in buf:
                yield json.loads(line)