developing couchbase part iii advanced app dev
TRANSCRIPT
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Developing with Couchbase Part III:Using the Client Libraries
John ZablockiDeveloper Advocate
@codevoyeur
{ " _id" : "John Zablocki”, "Title" : "Developer Advocate", "Company" : "Couchbase", "Books" : [ { "Title" : "Orchard CMS", "Publisher" : "O'Reilly" } ], "Twitter" : "@CodeVoyeur", "Email" : "[email protected]", "Meetup" : "Beantown ALT.NET“, "Code" : [
"https://github.com/jzablocki", http://bitbucket.com/johnzablockis
], "Blogs" : [
"http://dllhel.net", "http://blog.couchbase.com"
]}
About Me
● Documents, Objects and Schemas● View Review● .NET Client API● Demo: TapMap● Q & A
Agenda
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Preamble
All examples are in C# using the Couchbase .NET Client Library 1.2 (Developer Preview)
Download at couchbase.com/develop/net/next
Here's how to connect to Couchbase Server:
var config = new CouchbaseClientConfiguration();config.Urls.Add(new Uri(http://192.168.1.2:/8091/pools/default));config.Urls.Add(new Uri(http://192.168.1.3:/8091/pools/default));config.Bucket = “protected”;config.BucketPassword = “s3cr3t”;
var client = new CouchbaseClient(config);
View Review
Documents, Objectsand Schemas
View Review .NET View API
Demo: TapMap
Q & A
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Remember when we said that Couchbase documents were schema-less?
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Well, it’s not quite that simple…
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Recall those beer documents…
{"_id": "beer_abbey_ale","type": "beer","name": "Abbey Ale","brewery": "brewery_Brewery_Ommegang","abv": 7.1,"style": "Ale"
}A schema
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Where did it come from?
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A C# Class
public class Beer { public string Id { get; set; } public string Name { get; set; }
public double ABV { get; set; }
public override string Type { get { return "beer"; } }}
A schema
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Your object model often becomes your schema, but how?
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A C# Class
[Serializable]public class Beer{ [JsonProperty(PropertyName = "_id")] public string Id { get; set; } [JsonProperty("name")] public string Name { get; set; }
[JsonProperty("abv")] public double ABV { get; set; }
[JsonProperty(“type")] public override string Type { get { return "beer"; } }}
A schema mapping
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Storing your model in C#
var key = “beer_Three_Philosophers”;var getResult = client.GetWithCas(key);
var beer = getResult.Result;beer.Name = “Three Philosophers”;
var json = JsonConvert.Serialize(beer);var casResult = client.Cas(StoreMode.Set, key, json, getResult.Cas);
var message = casResult.Result ? “Success” : “Failure”; Console.WriteLine(message);
Schemafication
Yum!
View Review
Documents, Objectsand Schemas
View Review .NET View API
Demo: TapMap
Qestions
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These Couchbase guys really like their beer…
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Yeah, we do…
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It’s a much more interesting data source than Northwind, no?
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Beer Documents
{"_id": "beer_abbey_ale","_rev": "1-00003e56befe4b4f0000005600000112","$flags": 0,"$expiration": 0,"type": "beer","name": "Abbey Ale","brewery": "brewery_brewery_ommegang","abv": 7.1
}
Unique key
Document type
Awesome beer
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Let’s create an index on beer name…
_design/beers/_view/by_name
// map functionfunction (doc) { if (doc.type == "beer“ && beer.name) { emit(doc.name, null); }}
The results…[ {"id":"beer_abbey_ale","key":"Abbey Ale","value":null}, {"id":"beer_american_ale","key":"American Ale","value":null}, {"id":"beer_harpoon_ipa","key":"Harpoon IPA","value":null}, {"id":"beer_long_trail_ale","key":"Long Trail Ale","value":null}, {"id":"beer_old_yankee_ale","key":"Old Yankee Ale","value":null}, {"id":"beer_three_philosophers","key":"Three Philosophers","value":null} ]
.NET View API
Documents, Objectsand Schemas
View Review .NET View API
Demo: TapMap
Qestions
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Calling the view from .NET
via .NET
var view = client.GetView("beers", "by_name");
foreach(var item in view) { var beer = client.Get<Beer>(item.ItemId); Console.WriteLine(beer.Name);}
Design doc
View name
Document key
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Finding a beer by name…
_design/beers/_view/by_name?key=“Abbey Ale”
via .NET
var view = client.GetView("beers", "by_name") .Key(“Abbey Ale”) .FirstOrDefault();
var beer = client.Get<Beer>(item.ItemId);
Exact matc
h
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Finding a range of beers by name…
_design/beers/_view/by_name?startkey=“A”&endkey=“D”
var view = client.GetView("beers", "by_name").StartKey(“A”).EndKey(“D”);
foreach(var item in view) { var beer = client.Get<Beer>(item.ItemId); Console.WriteLine(beer.Name);}
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Limiting and skipping beers…
_design/beers/_view/by_name?limit=10&skip=2
var view = client.GetView("beers", "by_name").Limit(5).Skip(5);
foreach(var item in view) { var beer = client.Get<Beer>(item.ItemId); Console.WriteLine(beer.Name);}
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Finding a strong ale…
The view
function (doc) { if (doc.type == "beer" && doc.style && doc.abv) { emit([doc.style, doc.abv], null); }}
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Finding a strong ale…
C# Example
var view = client.GetView("beers", "by_style_and_abv")
.StartKey(new object[] { “Ale”, 6.0 })
.EndKey(new object[] { “Ale”, 10 });
foreach(var item in view) { var beer = client.Get<Beer>(item.ItemId); Console.WriteLine(beer.Name);}
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Finding breweries by province
The brewery document
{"_id": "brewery_cottrell_brewing","_rev": "1-00003e56c0e830c80000005900000112","$flags": 0,"$expiration": 0,"type": "brewery","name": "Cottrell Brewing","city": "Pawcatuck","province": "Connecticut"
}
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Finding breweries by province
The map function
function (doc) { if (doc.type == "brewery" && doc.province) { emit(doc.province, doc.name); }}
Map/Reduce – Map Results
• The conceptual output of the map function is
[
{"key":"Connecticut", "value":"Cottrell Brewing"}, {"key":"Connecticut","value":"Thomas Hooker Brewing Co."},
{"key":"Massachusetts","value":"Harpoon Brewing Company"}, {"key":"New York","value":"Brewery Ommegang"},
{"key":"Vermont","value":"Long Trail Brewing Company"}
]
Map/Reduce – Reduce Function
• A reduce function to count breweries by province– Or simply use the build in _count function
function (keys, values) { return values.length;}
• The conceptual input to the reduce function is:[ {"keys":["Connecticut", "Connecticut"],
"values": ["Cottrell Brewing", "Thomas Hooker Brewing Co."]}, {"keys":["Massachusetts"],"values":["Harpoon Brewing Co."]}, {"keys":["New York"],"values":["Brewery Ommegang"]},
{"keys":["Vermont"],"values":["Long Trail Brewing Company“]} ]
Map/Reduce – Reduce Results
• The conceptual result of the reduce is
{"key":"Connecticut","value":2}, {"key":"Massachusetts","value":1}, {"key":"New York","value":1}, {"key":"Vermont","value":1}
Map/Reduce .NET Code
_design/beers/_view/by_name?limit=10&skip=2
var view = client.GetView(“breweries", "by_province")
.Group(true);
foreach(var item in view) {
Console.WriteLine(item.ItemId);
}
Demo:TapMap
Documents, Objectsand Schemas
View Review .NET View API
Demo: TapMap
Qestions
TapMap
TapMap Info
• Written in C#, with ASP.NET MVC 4
• Code available at: http://github.com/couchbaselabs/TapMap
• Demonstrates common web app behaviors using Couchbase Server 2.0– Find a user in the database by username and password
– When creating a new user, verify a username and email are unique
– Filter a select list data source from the value of another
– Show data items on a map
• Demonstrates using a client library with common architectural patterns– Working with a Repository of T
– Creating a domain models• Document mapping
• Model inheritance
• Model composition
– Managing the client resources
Q&A
Documents, Objectsand Schemas
View Review .NET View API
Demo: TapMap
Q&A