relax your project with couchdb
Post on 18-Nov-2014
117 Views
Preview:
DESCRIPTION
TRANSCRIPT
Relax your project with CouchDB
Benoît Chesneau26/05/2010 - djangocon berlin
Wednesday, May 26, 2010
• Why using a “NoSQL” solution ?
• CouchDB ?
• CouchDBKit: CouchDB & Django
Wednesday, May 26, 2010
• CouchDB developer• Maintainer of CouchDBkit,
Couchbeam, Couchapp , couchdbproxy, ...
• benoitc@apache.org
Why i’m here
Wednesday, May 26, 2010
• We don’t need “scalability” sometimes• Most of DB size < 300 GB (2 GB)• All my data could be on a machine
(comcast)• Often, DB requests are fast enough
Why NOSQL ?
Wednesday, May 26, 2010
Agile
• Different kinds of data• Easy denormalisation• Migrate your data easily• Keep your data safe• Flexibility, Simplicity
Wednesday, May 26, 2010
KEEP YOUR DATA SAFE
Wednesday, May 26, 2010
Order Customer Delivery
Item Item
Ex. Shop
Wednesday, May 26, 2010
• Oriented Document Database• REST• Map/Reduce (M/R)• Append-Only• Javascript/Erlang• Replication
CouchDB
Wednesday, May 26, 2010
Document Oriented?
• Schema-less• JSON• Attachments
Wednesday, May 26, 2010
JSON DOCUMENT
{ "_id": "foo", "_rev": "1-....", "url": "http://apache.couchdb.org", "vote": 1}
Wednesday, May 26, 2010
FutonWednesday, May 26, 2010
Map/Reduce ?
• Map (M) : Collect a list of values associated to a key
• Return a K-V list• Reduce (R) : Reduce a list of K-V in one
list of values• Rereduce
Wednesday, May 26, 2010
MAP.JS
function(doc) { if (doc.url && doc.vote) emit(doc.url, doc.vote);}
Wednesday, May 26, 2010
{ "total_rows": 3, "offset": 0, "rows": [{ "id": "15c92051cc81d564db4337a05087bc8d", "key": "http://apache.couchdb.org", "value": 1 }, { "id": "fa9658810d25cac893748e4ff15e7253", "key": "http://apache.couchdb.org", "value": 1 }, { "id": "1fa0c68d8455196507b8b01645e65186", "key": "http://mysql.com", "value": -1 }]}
Wednesday, May 26, 2010
REDUCE.JS
function(keys, values, rereduce) { return sum(values);}
{ "rows": [ { "key": "http://mysql.com", "value": -1 }, { "key": "http://apache.couchdb.org", "value": 2 } ]}
Wednesday, May 26, 2010
Réplicatuon
• Incremental• Master-Master• Continue or when needed
Wednesday, May 26, 2010
Wednesday, May 26, 2010
Wednesday, May 26, 2010
Wednesday, May 26, 2010
Wednesday, May 26, 2010
Wednesday, May 26, 2010
Wednesday, May 26, 2010
Wednesday, May 26, 2010
Wednesday, May 26, 2010
More
• Sharding: yes• couchdb-lounge, cloudant, yours• Geocouch. Full r-tree
Wednesday, May 26, 2010
couchdbkit
Wednesday, May 26, 2010
CouchDBKit
• CouchDB Python framework• support CouchDB 0.10.2 & 0.11.0• Simple client• Object Document Mapping (“ODM”)• Django extension• Couchapp compatible
Wednesday, May 26, 2010
client
from couchdbkit import Server
s = Server("http://127.0.0.1:5984")db = s["mydb"]doc = { "a": 1 }db.save_doc(doc)doc["b"] = 2db.save(doc)
doc1 = db.get(doc['_id'])
Wednesday, May 26, 2010
Other features
• db.views• from couchdbkit.loaders import
FileSystemDocsLoader
Wednesday, May 26, 2010
from couchdbkit.loaders import FileSystemDocsLoader
loader = FileSystemDocsLoader('/path/to/example/_design')loader.sync(db, verbose=True)
Wednesday, May 26, 2010
Object Document Mapping
from couchdbkit.schema import *
class MyDoc(Document): a = IntegerProperty() contain(db, MyDoc)
doc = MyDoc()doc.a = 1doc.save()
doc.b = 2doc.save()
doc1 = MyDoc.get(doc._id)
Wednesday, May 26, 2010
Django Extension
• from couchdbkt.ext.django import *• Django helper• manage.py syncdb• DocumentForm
Wednesday, May 26, 2010
settings.py
...
COUCHDB_DATABASES = ( ('djangoapp.greeting', 'http://127.0.0.1:5984/greeting'), )
...
INSTALLED_APPS = ( ... 'couchdbkit.ext.django', 'djangoapp.greeting', ... )
Wednesday, May 26, 2010
models.py
from datetime import datetimefrom couchdbkit.ext.django.schema import *
class Greeting(Document): author = StringProperty() content = StringProperty(required=True) date = DateTimeProperty(default=datetime.utcnow)
Wednesday, May 26, 2010
forms.py
class GreetingForm(DocumentForm): class Meta: document = Greeting
Wednesday, May 26, 2010
views.py
def home(request): greet = None if request.POST: form = GreetingForm(request.POST) if form.is_valid(): greet = form.save() else: form = GreetingForm() greetings = Greeting.view("greeting/all") return render("home.html", { "form": form, "greet": greet, "greetings": greetings }, context_instance=RequestContext(request))
Wednesday, May 26, 2010
0.5
• New mapping (Objects with annotations)
• Admin integration• Possibility to attach design doc to some
objects• MultiDB & DB backend in extension• Eventlet support
Wednesday, May 26, 2010
Wednesday, May 26, 2010
Liens
• http://apache.couchdb.org• http://couchdbkit.org
Wednesday, May 26, 2010
Questions
Wednesday, May 26, 2010
@benoitc
Wednesday, May 26, 2010
Cette création est mise à disposition selon le Contrat Paternité 2.0 France disponible en ligne http://
creativecommons.org/licenses/by/2.0/fr/ ou par courrier postal à Creative Commons, 171 Second Street, Suite
300, San Francisco, California 94105, USA.
Wednesday, May 26, 2010
top related