github.com/IBM-Swift/Kitura-CouchDB

Kitura-CouchDB

Kitura-CouchDB is a pure Swift client which allows Kitura applications to interact with a CouchDB or Cloudant database.

Usage

Add dependencies

Add the Kitura-CouchDB package to the dependencies within your application’s Package.swift file. Substitute "x.x.x" with the latest Kitura-CouchDB release.

.package(url: "https://github.com/Kitura/Kitura-CouchDB.git", from: "x.x.x")

Add CouchDB to your target's dependencies:

.target(name: "example", dependencies: ["CouchDB"]),

Import package

import CouchDB

Run Kitura-CouchDB Sample

To run the CouchDB Sample, you must set up and connect to a local CouchDB database by following the steps below:

1. Download and install CouchDB.

2. Set up an admin username and password in CouchDB.

3. Create a database with the name kitura_test_db.

4. Clone this repository:

   git clone https://github.com/Kitura/Kitura-CouchDB.git
   

5. Update the following code in Sources\CouchDBSample\main.swift with your admin username and password (the host will default to 127.0.0.1 and the port will default to 5984):

   let connProperties = ConnectionProperties(
       host: host,         // http address
       port: port,         // http port
       secured: secured,   // https or http
       username: nil,      // admin username
       password: nil       // admin password
   )
   

6. Open a Terminal window, change into the Kitura-CouchDB folder and run swift build:

   swift build
   

7. Run the CouchDBSample executable:

   .build/debug/CouchDBSample
   

   You should see informational messages such as "Successfully created the following JSON document in CouchDB:" for each of the operations (create, read, update and delete) performed on the kitura_test_db database.

API Documentation

Document

CouchDB is a NoSQL database for storing documents. A Document is any structure that can be represented as JSON and contains _id and _rev fields.

• The _id field is the unique identifier for the document. If it is not set, a random UUID will be assigned for the document.
• The _rev field is the revision of the document. It is returned when you make requests and is used to prevent conflicts from multiple users updating the same document.

To define a CouchDB document, create a Swift object and make it conform to the Document protocol:

struct MyDocument: Document {
   let _id: String?
   var _rev: String?
   var value: String
}

CouchDBClient

The CouchDBClient represents a connection to a CouchDB server. It is initialized with your ConnectionProperties and handles the creation, retrieval and deletion of CouchDB databases.

// Define ConnectionProperties
let conProperties = ConnectionProperties(
    host: "127.0.0.1",              // http address
    port: 5984,                     // http port
    secured: false,                 // https or http
    username: "<CouchDB-username>", // admin username
    password: "<CouchDB-password>"  // admin password
)
// Initialize CouchDBClient
let couchDBClient = CouchDBClient(connectionProperties: conProperties)

• Create a new database

couchDBClient.createDB("NewDB") { (database, error) in
    if let database = database {
        // Use database
    }
}

• Get an existing database

couchDBClient.retrieveDB("ExistingDB") { (database, error) in
    if let database = database {
        // Use database
    }
}

• Delete a database

couchDBClient.deleteDB("ExistingDB") { (error) in
    if let error = error {
        // Handle the error
    }
}

Database

The Database class is used to make HTTP requests to the corresponding CouchDB database. This class can make CRUD (Create, Retrieve, Update, Delete) requests for:

• A single CouchDB Document
• An array of CouchDB documents
• A CouchDB DesignDocument
• A Document attachment

The following code demonstrates the CRUD operations for a single Document:

var myDocument = MyDocument(_id: "Kitura", _rev: nil, value: "Hello World")

• Create a Document:

database.create(myDocument) { (response, error) in
    if let response = response {
        print("Document: \(response.id), created with rev: \(response.rev)")
    }
}

• Retrieve a Document:

database.retrieve("Kitura") { (document: MyDocument?, error: CouchDBError?) in
    if let document = document {
        print("Retrieved document with value: \(document.value)")
    }
}

• Update a Document:

myDocument.value = "New Value"
database.update("Kitura", rev: "<latest_rev>", document: myDocument) { (response, error) in
    if let response = response {
        print("Document: \(response.id), updated")
    }
}

• Delete a Document:

database.delete("Kitura", rev: "<latest_rev>") { (error) in
    if error == nil {
        print("Document successfully deleted")
    }
}

For more information visit our API reference.

Community

We love to talk server-side Swift, and Kitura. Join our Slack to meet the team!

License

This library is licensed under Apache 2.0. Full license text is available in LICENSE.