diff --git a/app/dbinit.py b/app/dbinit.py
new file mode 100644
index 0000000..29ed7cf
--- /dev/null
+++ b/app/dbinit.py
@@ -0,0 +1,91 @@
+"""
+Mongodb storage init 
+
+- collections creation
+- helper queries
+
+"""
+import urllib.parse
+
+from unidecode import unidecode # to remove accents in house and prince names in the urls
+from pymongo import MongoClient
+
+from .config import dbadmin, dbpassword, server_ip
+
+# TODO : maybe put the mongodb connector in the flask app object
+# ______________________________________________________________________________
+# database connexion
+username = urllib.parse.quote_plus(dbadmin)
+password = urllib.parse.quote_plus(dbpassword)
+dbclient = MongoClient(f'mongodb://{username}:{password}@{server_ip}:27017')
+# database
+actesdb = dbclient["actesdb"]
+# collections
+housecol = actesdb["house"]
+# the acte collection is the most important collection
+actecol = actesdb["acte"]
+helpers = actesdb["helpers"]
+#folium_map = actesdb["folium_map"]
+
+# ______________________________________________________________________________
+# storage extractor utilities
+
+def extract_princes_in_houses():
+    """Extracts all princes from a house
+    by queries in the storage, (not by using csv metadatas)
+
+    sample:
+    >>> extract_princes_in_houses['anjou']
+    [{'prince_name': "Louis Ier d'Anjou", 'prince_code': 'lo_i'}, {'prince_name': "Louis III d'Anjou", 'prince_code': 'lo_iii'}, {'prince_name': 'Isabelle de Lorraine', 'prince_code': 'isa_i'}, {'prince_name': "Louis II d'Anjou", 'prince_code': 'lo_ii'}, {'prince_name': 'Marie de Blois', 'prince_code': 'mar_i'}, {'prince_name': "René d'Anjou", 'prince_code': 're_i'}, {'prince_name': "Yollande d'Aragon", 'prince_code': 'yol_i'}]
+    """
+    princes_in_houses = dict()
+    for house in housecol.find():
+        housename = house['name'].lower()
+        query = list(actecol.aggregate([{"$match": {"house": housename}}, {'$group': {'_id': {'prince_name': '$prince_name', 'prince_code': '$prince_code'}}}]))
+        princes_in_houses[housename] = [pr['_id'] for pr in query]
+    return princes_in_houses
+
+
+def normalize_trigrams(trigram):
+    """normalizes names, usefull for the uris routes
+
+    sample: Alençon -> Alencon
+            Orléans -> Orleans
+    """
+    return {unidecode(value):key for key, value in trigram.items()}
+
+# ______________________________________________________________________________
+# in memory storage extracted meta informations on the database
+# TODO: if it takes too much time at launch, put it in something like
+# a `flask init` procedure
+
+helpers_dicts = helpers.find_one()
+house_trigram = helpers_dicts["house_trigram"]
+prince_bigram = helpers_dicts["prince_bigram"]
+
+princes_in_houses = extract_princes_in_houses()
+# normalized_trigrams
+house_trigram = normalize_trigrams(house_trigram)
+prince_bigram = normalize_trigrams(prince_bigram)
+
+def bigram_prince(prince):
+    "Translates Charles_i -> ch_i"
+    name, number = prince.split("_")
+    return prince_bigram[name] + "_" + number
+
+# TODO: write tests in the datascience project `datascience/tests`
+#print(bigram_prince("Agnes"))
+#print(bigram_prince("Arthur"))
+#print(bigram_prince("Bernard"))
+#print(trigram_house("Anjou"))
+#print(trigram_house("Orleans"))
+
+def trigram_house(house):
+    return house_trigram[house]
+
+
+def make_acteid_from_route(house=None, prince=None, date_and_item=None):
+    "/acte/Anjou/Isabelle_i/1441_08_05a -> anj_isa_i_1441_08_05a"
+    return "_".join([trigram_house(house), bigram_prince(prince), date_and_item])
+
+
diff --git a/app/routes.py b/app/routes.py
index e5b08f8..ccd3008 100644
--- a/app/routes.py
+++ b/app/routes.py
@@ -1,93 +1,14 @@
 import typing as t
-import urllib.parse
-from unidecode import unidecode # to remove accents in house and prince names in the urls
+
 
 from flask import Blueprint, abort, render_template, request, send_from_directory
-from pymongo import MongoClient
 import folium
 
-from .config import dbadmin, dbpassword, server_ip
 from .helper import find_one_or_404
-
+from .dbinit import *
 
 main = Blueprint("main", __name__, url_prefix="/")
 
-# TODO : maybe put the mongodb connector in the flask app object
-# ______________________________________________________________________________
-# database connexion
-username = urllib.parse.quote_plus(dbadmin)
-password = urllib.parse.quote_plus(dbpassword)
-dbclient = MongoClient(f'mongodb://{username}:{password}@{server_ip}:27017')
-# database
-actesdb = dbclient["actesdb"]
-# collections
-housecol = actesdb["house"]
-# the acte collection is the most important collection
-actecol = actesdb["acte"]
-helpers = actesdb["helpers"]
-#folium_map = actesdb["folium_map"]
-
-# ______________________________________________________________________________
-# storage extractor utilities
-
-def extract_princes_in_houses():
-    """Extracts all princes from a house
-    by queries in the storage, (not by using csv metadatas)
-
-    sample:
-    >>> extract_princes_in_houses['anjou']
-    [{'prince_name': "Louis Ier d'Anjou", 'prince_code': 'lo_i'}, {'prince_name': "Louis III d'Anjou", 'prince_code': 'lo_iii'}, {'prince_name': 'Isabelle de Lorraine', 'prince_code': 'isa_i'}, {'prince_name': "Louis II d'Anjou", 'prince_code': 'lo_ii'}, {'prince_name': 'Marie de Blois', 'prince_code': 'mar_i'}, {'prince_name': "René d'Anjou", 'prince_code': 're_i'}, {'prince_name': "Yollande d'Aragon", 'prince_code': 'yol_i'}]
-    """
-    princes_in_houses = dict()
-    for house in housecol.find():
-        housename = house['name'].lower()
-        query = list(actecol.aggregate([{"$match": {"house": housename}}, {'$group': {'_id': {'prince_name': '$prince_name', 'prince_code': '$prince_code'}}}]))
-        princes_in_houses[housename] = [pr['_id'] for pr in query]
-    return princes_in_houses
-
-
-def normalize_trigrams(trigram):
-    """normalizes names, usefull for the uris routes
-
-    sample: Alençon -> Alencon
-            Orléans -> Orleans
-    """
-    return {unidecode(value):key for key, value in trigram.items()}
-
-# ______________________________________________________________________________
-# in memory storage extracted meta informations on the database
-# TODO: if it takes too much time at launch, put it in something like
-# a `flask init` procedure
-
-helpers_dicts = helpers.find_one()
-house_trigram = helpers_dicts["house_trigram"]
-prince_bigram = helpers_dicts["prince_bigram"]
-
-princes_in_houses = extract_princes_in_houses()
-# normalized_trigrams
-house_trigram = normalize_trigrams(house_trigram)
-prince_bigram = normalize_trigrams(prince_bigram)
-
-def bigram_prince(prince):
-    "Translates Charles_i -> ch_i"
-    name, number = prince.split("_")
-    return prince_bigram[name] + "_" + number
-
-# TODO: write tests in the datascience project `datascience/tests`
-#print(bigram_prince("Agnes"))
-#print(bigram_prince("Arthur"))
-#print(bigram_prince("Bernard"))
-#print(trigram_house("Anjou"))
-#print(trigram_house("Orleans"))
-
-def trigram_house(house):
-    return house_trigram[house]
-
-
-def make_acteid_from_route(house=None, prince=None, date_and_item=None):
-    "/acte/Anjou/Isabelle_i/1441_08_05a -> anj_isa_i_1441_08_05a"
-    return "_".join([trigram_house(house), bigram_prince(prince), date_and_item])
-
 # ______________________________________________________________________________
 # routes