CouchDBProxy

Simple multinode couchdb proxy. It allows you to proxy from one IP address to multiple couchdb nodes running on different IPs or ports. CouchDBProxy also supports streaming, some basic url rewriting and domain aliasing. You could add/remove a user couchdb node or a domain alias dynamically. So basically it allows you to host a little couch.io like on your own site.

With CouchDBProxy you could do something like

http://someuser.yourdomain.com -> someip:someport

or

http://mydomain.com - someip:someport/mydb/_design/mycouchapp
http://someuser.yourdomain.com -> someip:someport

CouchDBProxy uses couchbeam to dialog with CouchDB and mochiweb for HTTP syntax-management.

Installation

Users of 0.2 you can migrate your data to the new api by running ./scripts/migrate01.py. It will update your views and migrate data.

1. Requirements

• bind 9 or any dnDNSs server that handle wildcards in ANAME. -
• CouchDB 0.10.x or newer.
• Python CouchdbKit for console utilities & basic setup.

2. Configure Bind

Add your our zone. Here is an example to configure a local zone for development though configuration is the same for production server, you just have to change the domain name.

in named.conf add:

zone "CouchDBProxy.dev" {
        type master;
        file "CouchDBProxy.dev.zone";
        allow-transfer { localhost; };
};

then add a zone. On my machine it's in /var/named. Create a file couchdbproxy.dev.zone:

$TTL    86400
@       IN      SOA     ns.couchdbproxy.dev. root.couchdbproxy.dev.  (
                                      2009091111 ; Serial
                                      10800       ; Refresh
                                                                          3600        ; Retry
                                                                          3600000     ; Expire
                                                                          86400 )     ; Minimum

              IN      NS      ns0.couchdbproxy.dev.

              IN      A       127.0.0.1
ns0           IN      A       127.0.0.1
*             IN      A       127.0.0.1

3. Configure Master Couchdb Node.

This node will be used to store and retrieve dynamically nodes for one user and cname. Install CouchDB somewhere by following CouchDB installation and set your en configuration file. All configuration is set in couchdbproxy application environment at startup. One full configuration file is in config:

{couchdbproxy_hostname, "couchdbproxy.dev"}. % base hostname used for rewriting
{couchdbproxy_name, couchdbproxy}. % erlang node name
{couchdbproxy_port, 8000}. % port on which couchdbproxy listen
{couchdbproxy_ip, "0.0.0.0"}. % ip of couchdbproxy
{couchdbproxy_cookie, 'couchdbproxy_cookie_default'}. % erlang cookiue
{couchbeam_heart_command, "start.sh"}. % heartbeat command

% params of couchdb node used to maintain connections user-couchdb
{couchdbproxy_couchdb_params, [{host, "127.0.0.1"}, {port, 5984}]}. % parameters of master couchdb 
{couchdbproxy_db, "couchdbproxy"}. % couchdb database

couchdbproxy_hostname is the basename used to detect CNAME and user urls. couchdbproxy_port is the port on which you want to run CouchDBProxy.

if you want to add an admin username/password do, change couchdbproxy_couchdb_params accordingly:

{proxy_hostconfig, [{host, "127.0.0.1"}, {port, 5984}, {username, "someuser"}, {password, "somepassword"}]}.

4. Build CouchDBProxy and Setup the Basic Design Doc:

Install couchdbkit:

easy_install -U couchdbkit

Then, in CouchDBProxy source folder run:

make && make setup

That's it.

Play with CouchDBProxy

You can add a node, username, alias dynamically thanks to the couchdproxy script in scripts folder.

run couchdbproxy

At development run start-dev.sh script:

./start-dev.sh config/couchdbproxy.erlenv

Or in production you could run start.sh script:

./start.sh config/couchdbproxy.erlenv

basic usage

The first thing you have to do is to setup a machine You can launch CouchDB nodes on this machine on different ports. To add a machine on localhost run:

./couchdbproxy.py add_machine http://127.0.0.1:5984 m0 127.0.0.1

Then you want to set a couchdb node on m0 machine:

./couchdbproxy.py add_node http://127.0.0.1:5984 m0 benoitc 5985

Connect on `http://benoitc.couchdbproxy.dev:8000` and you will fall in
benoitc node.

To remove this node :

./couchdbproxy.py remove_node http://127.0.0.1:5984 benoitc

Get more usage by running command ./couchdbproxy.py --help

Cool Features

There are cool url rewriting offered by CouchDBProxy that allows you to access easily on a database or a couchapp. For example:

If the user benoitc has a database blog on its node, you can access it with the url http://blog.benoitc.CouchDBProxy.dev:8000. If there is a couchapp in this database named myblog, you can also access to it with the url http://myblog.blog.benoitc.CouchDBProxy.dev:8000.

Now imagine, you have a domain name called benoitc.local and want to access to the the couchapp myblog in blog db from benoitc's couchdb node. You could do it easily by pointing benoitc.local to your node and add an alias:

./couchdbproxy.py add_alias http://127.0.0.1:5984 benoitc benoitc.local /blog/_design/myblog

Easy!

Todo:

• caching with redis/memcached
• add more dispatching possibilities
• ...