add param WORDS_FILE_PATH, use random_words when generating email

app/config.py

@@ -57,3 +57,5 @@ PARTNER_CODES = ["SL2019"]
 
 # Allow user to have 1 year of premium: set the expiration_date to 1 year more
 PROMO_CODE = "SIMPLEISBETTER"
+
+WORDS_FILE_PATH = os.environ.get("WORDS_FILE_PATH")

app/models.py

@@ -9,11 +9,11 @@ from flask_login import UserMixin
 from sqlalchemy_utils import ArrowType
 
 from app import s3
-from app.config import URL, MAX_NB_EMAIL_FREE_PLAN, EMAIL_DOMAIN
+from app.config import EMAIL_DOMAIN, MAX_NB_EMAIL_FREE_PLAN, URL
 from app.extensions import db
 from app.log import LOG
 from app.oauth_models import Scope
-from app.utils import convert_to_id, random_string
+from app.utils import convert_to_id, random_string, random_words
 
 
 class ModelMixin(object):
@@ -308,7 +308,7 @@ class OauthToken(db.Model, ModelMixin):
 
 def generate_email() -> str:
     """generate an email address that does not exist before"""
-    random_email = random_string(40) + "@" + EMAIL_DOMAIN
+    random_email = random_words() + "@" + EMAIL_DOMAIN
 
     # check that the client does not exist yet
     if not GenEmail.get_by(email=random_email):

app/utils.py

@@ -4,6 +4,19 @@ import urllib.parse
 
 from unidecode import unidecode
 
+from .config import WORDS_FILE_PATH
+from .log import LOG
+
+with open(WORDS_FILE_PATH) as f:
+    LOG.d("load words file: %s", WORDS_FILE_PATH)
+    _words = f.read().split()
+
+
+def random_words():
+    """Generate a random words. Used to generate user-facing string, for ex email addresses"""
+    nb_words = random.randint(3, 5)
+    return "_".join([random.choice(_words) for i in range(nb_words)])
+
 
 def random_string(length=10):
     """Generate a random string of fixed length """

tests/test_utils.py

@@ -0,0 +1,11 @@
+from app.utils import random_string, random_words
+
+
+def test_random_words():
+    s = random_words()
+    assert len(s) > 0
+
+
+def test_random_string():
+    s = random_string()
+    assert len(s) > 0