===== CouchBase =====

==== CouchBase Lite ====


=== Authentication ===

== Registration of new users ==
Creating a User is done via the Admin Port of the REST API: \\
http://developer.couchbase.com/mobile/develop/guides/sync-gateway/administering-sync-gateway/authorizing-users/index.html

<code>
curl -X POST http://localhost:4985/${db}/_user/ -d '{"name":"foo", "password":"bar"}'
</code>
== Restrict reading the document ==
Channels legitimate a user to read documents.
A user is legitimated to access a channel.
User's documents are marked by channels.

== Restrict writing the document to it's owner ==
This is done inside the **Sync function**, which is defined during the start of the Sync Gateway 
<code>
# this required the currently logged in user - to be the sam as mentioned in oldDoc's user property
requireUser(oldDoc.user)
</code>

The write restriction may be defined by:
  * rolename
  * channel
  * username

http://developer.couchbase.com/mobile/develop/guides/sync-gateway/sync-function-api-guide/validation/index.html



=== Manual Authentication ===

     * Your app prompts user for credentials
     * Your app directly contacts your app server with these credentials
     * Your app server creates a session on the Sync Gateway, which returns a cookie
     * Your app server returns this cookie to your app

http://wiki.nginx.org/Modules
NGinx may be used 
  * to implement a reverse Proxy, to protect the connection with SSL
  * with embedded PERL
  * provide the user registration API


==== CouchBase ====
The NoSQL Server. Stores data as documents.


==== Sync Gateway ====

== Glossary ==

|DataBase| The database maps to a bucket. A single Sync Gateway may publish buckets as databases. Below the DB **gw** points to the bucket **sync_gateway**|
|Server| The server is the storage, where the Sync Gateway will put hte data in. It may be a Couchase Server or a Walrus Server (File System DB)          "server":"C:\Couchbase\Walrus\default.walrus"|

<code>
{
   "log": ["CRUD", "CRUD+", "HTTP", "HTTP+", "Access", "Cache", "Changes", "Changes+"],
   "interface":":4984",
   "adminInterface":":4985",
   "facebook":{
      "register":true
   },
   "databases":{
      "gw":{
         "server":"http://localhost:8091",
         "bucket":"sync_gateway",
         "sync":`function(doc) {
			if (doc._deleted) {
				requireUser(oldDoc.writers);
				return;
			}
			if (!doc.title || !doc.creator || !doc.writers) {
				throw({forbidden: "Missing required properties"});
			} else if (doc.writers.length == 0) {
				throw({forbidden: "No writers"});
			}
			if (oldDoc == null) {
				requireUser(doc.creator);
			} else {
				requireUser(oldDoc.writers);
				if (doc.creator != oldDoc.creator) {
					throw({forbidden: "Can't change creator"});
				}
			}
			// add channel with the username to the doc
			channel ("channel_" + doc.creator);

			// add access to the channel username to the user
			access (doc.creator, [doc.creator, "*"]);
			
		 }`,
		 "users": {
				"GUEST": {"disabled": true, "admin_channels": ["*"] }
		  }
      }
   },
  "persona" : {
     "origin" : "http://example.com/",
     "register" : true
  }
}
</code>


== Create user, assign channel==
User has to have access to it's own channel, in order to have the ability to read docs.

<sxh powershell>
# Sync Gateway request:  Create a new user via a direct Sync Gateway request
$method = "PUT"
$resource = "http://192.168.191.210:4985/gw/_user/skipxxx"
$body = "{
    ""name"":""skipxxx"",
    ""password"":""pass"",
    ""admin_channels"":[""channel_skipxxx""],
    ""admin_roles"":[""editor""],
    ""disabled"":false
}"
echo $body;
Invoke-RestMethod -Method $method -Uri $resource -Body $body -ContentType 'application/json'
</sxh>


== Create a doc  which is assigned to user's channel==
Assigning is done automatically, by the **sync_funcion**, when a user creates a document. see 
<code>
// add channel with the username to the doc
channel ("channel_" + doc.creator);
</code>

Alternatively the doc may be added by powershell
<sxh powershell>
# create a document by REST API
$now = $(get-date);
$resource = "http://192.168.191.210:4985/gw/"
$method = "POST"
$body = "{
    ""type"":""FromConsoleType3"",
    ""title"":""Document from Console3"",
    ""checked"":""true"",
    ""created_at"":""$now"",
    ""creator"":""skipxxx"",
    ""writers"":[""skipxxx""]
}"
$securepassword = ConvertTo-SecureString "pass" -AsPlainText -Force
$credentials = New-Object System.Management.Automation.PSCredential("skipxxx", $securepassword)
Invoke-WebRequest -Uri $resource -Method POST -Credential $credentials -Body $body  -ContentType application/json
</sxh>

This is how the document may look like

<code>
{
  "_sync": {
    "rev": "1-ec4f884fae1ded971b5fbd18f9c07060",
    "sequence": 7,
    "history": {
      "revs": [
        "1-ec4f884fae1ded971b5fbd18f9c07060"
      ],
      "parents": [
        -1
      ],
      "bodies": [
        ""
      ],
      "channels": [
        [
          "channel_skipxxx"
        ]
      ]
    },
    "channels": {
      "channel_skipxxx": null
    },
    "access": {
      "skipxxx": {
        "skipxxx": 7
      }
    },
    "time_saved": "2015-06-21T11:55:23.1276655-07:00"
  },
  "checked": "true",
  "created_at": "06/21/2015 20:55:17",
  "creator": "skipxxx",
  "title": "Document from Console3",
  "type": "FromConsoleType3",
  "writers": [
    "skipxxx"
  ]
}
</code>

The channels which this doc is assigned to is listed here:
<code>
    "channels": {
      "channel_skipxxx": null
    },
</code>


== Now the docs may be synced  ==
The docs may be synced, without setting any channel.
Then all available docs will be pulled 
<sxh java>
        pullReplication = database.createPullReplication(syncUrl);
        pullReplication.setContinuous(true);

        pushReplication = database.createPushReplication(syncUrl);
        pushReplication.setContinuous(true);
                
        pushReplication.start();
        pullReplication.start();
</sxh>