Moya plugins are used to perform some side effect whenever a request is sent or received. Plugins are defined by the PluginType protocol, which can receive callbacks when:
- a request is going to be sent;
- a response has been received.
##Built in plugins Moya ships with some default plugins which can be used for common functions: authentication, network activity indicator management and logging. You can use a plugin simply declaring it during the initialization of the provider:
let provider = MoyaProvider<GitHub>(plugins: [NetworkLoggerPlugin(verbose: true)])####Authentication
The authentication plugin allows a user to assign an optional NSURLCredential per request. There is no action when a request is received.
The plugin can be found at Source/Plugins/CredentialsPlugin.swift
####Network Activity Indicator One very common task with iOS networking is to show a network activity indicator during network requests, and remove it when all requests have finished. The provided plugin adds callbacks which are called when a requests starts and finishes, which can be used to keep track of the number of requests in progress, and show / hide the network activity indicator accordingly.
The plugin can be found at Source/Plugins/NetworkActivityPlugin.swift
####Logging During development it can be very useful to log network activity to the console. This can be anything from the URL of a request as sent and received, to logging full headers, method, request body on each request and response.
The provided plugin for logging is the most complex of the provided plugins, and can be configured to suit the amount of logging your app (and build type) require. When initializing the plugin, you can choose options for verbosity, whether to log curl commands, and provide functions for outputting data (useful if you are using your own log framework instead of print) and formatting data before printing (by default the response will be converted to a String using NSUTF8StringEncoding but if you'd like to convert to pretty-printed JSON for your responses you can pass in a formatter function, see the function JSONResponseDataFormatter in Demo/Demo/GitHubAPI.swift for an example that does exactly that)
The plugin can be found at Source/Plugins/NetworkLoggerPlugin.swift
##Custom plugins
Every time you need to execute some pieces of code before a request is sent and/or immediately after a response, you can create a custom plugin, implementing the PluginType protocol.
For an example of creating a new plugin, see docs/Examples/CustomPlugin.md