Mimic

Mimic is a simple library for stubbing network request.

• Integration
• Usage
  • Adding new stub
  • Randomize stubs
  • Using wild card parameters
  • Removing Stubs
• Testing
• Limitations

Integration

Cocoapods

Using Mimic with Cocoapods.

To integrate Mimic into your Xcode project, add the following to your Podfile.

    pod 'Mimic', '~> 1.3.1'

Swift Package Manager

Using Mimic with Swift Package Manager.

Add Mimic as a dependcy in your Package.swift file.

dependencies: [
    .package(url: "https://github.com/feliperuzg/Mimic", .upToNextMajor(from: "1.3.1"))
]

Carthage

Using Mimic with Carthage.

To integrate Mimic into your Xcode project, add the following to your Cartfile.

github "feliperuzg/Mimic" 

Usage

Adding new stub

To create a new stub use

@discardableResult public class func mimic(
    request: @escaping MimicRequest,
    delay: TimeInterval = 0,
    response: @escaping MimicResponse
) -> MimicObject

Where MimicRequest is constructed like:

request(with method: MimicHTTPMethod, url: String, wildCard: Bool = false)

And MimicResponse is constructed like:

response(with json: Any status: Int = 200, headers: String : String]? = nil)

Example:

let stub = Mimic.mimic(
    request: request(with: .get, url: "http://example.com"),
    delay: 2,
    response: response(with: ["response": true], status: 200, headers: ["SomeHeader": "SomeValue"]) 
)

You could also prefer not to store the MimicObject that's returned, like:

Mimic.mimic(
    request: request(with: .get, url: "http://example.com"),
    delay: 2,
    response: response(with: ["response": true], status: 200, headers: ["SomeHeader": "SomeValue"]) 
)

Randomize stubs

Mimic supports returning a random mimic for the same request, to archive this just add more than one mimic for the same request, for example:

Mimic.mimic(
    request: request(with: .get, url: "http://example.com"),
    delay: 2,
    response: response(with: ["response": true], status: 200]) 
)

Mimic.mimic(
    request: request(with: .get, url: "http://example.com"),
    delay: 2,
    response: response(with: ["response": false], status: 400]) 
)

And finally activate the randomize fuction by activating it's parameter in Mimic

Mimic.randomizeMimics = true

This will search all mimics for a request and return a random element.

Using wild card parameters

Mimic support adding multiple wild card parameters inside an url by replacing the string with @wild. This will allow to stub request to endpoints with dynamic paramters inside path o query, for example:

Let's take as example the followig url

http://example.com/path1/path2?item1=value1&&item2=value2

Adding wild parameter to path parater path2

http://example.com/path1/@wild?item1=value1&&item2=value2

Adding wild parameter to query parameter value1

http://example.com/path1/path2?item1=@wild&&item2=value2

Adding wild paramter to both path2 and value1

http://example.com/path1/@wild?item1=@wild&&item2=value2

Removing stubs

To remove a single stub you can use

public class func stopMimic(_ mimic: MimicObject)

For Example:

This will add a new stub

let stub = Mimic(
    request: request(with: .get, url: "http://example.com"),
    delay: 2,
    response: response(with: ["response": true))
)

For removing it you would do:

Mimic.stopMimic(stub)

For removing all stubs call:

Mimic.stopAllMimics()

Testing

To ensure the URLSessionConfiguration swizzle is performed before the request it's recommended to initialize Mimic first

class myTests: XCTests {
    ...
    // Test properties here
    override func setUp() {
        super.setUp()
        Mimic.start()
        ...
        // Other initializers
    }
    ...
    // Other tests functions
}

Limitations

Mimic only support simple request, it doesn't support downloading or uploading tasks yet.

Request methods are limited to:

• GET
• POST
• DELETE
• PUT