Page Comparison

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• APIAuthenticationHandler : Validates the OAuth2 bearer token used to invoke the API. It also determines whether the token is of type Production or Sandbox and sets MessageContext variables as appropriate. To extend the default authentication handler, see Writing a Custom Authentication Handler.
• APIThrottleHandler : Throttles requests based on the throttling policy specified by the policyKey property. Throttling is applied both at the application level as well as subscription level.
• APIMgtUsageHandler : Publishes events to BAM for collection and analysis of statistics. This handler only comes to effect if API usage tracking is enabled. See Monitoring using WSO2 BAM See Publishing API Runtime Statistics for more information.
• APIMgtGoogleAnalyticsTrackingHandler : Publishes events to Google Analytics. This handler only comes into effect if Google analytics tracking is enabled. See Integrating with Google Analytics for more information.
• APIManagerExtensionHandler : Extends the mediation flow of messages passing through the API Gateway. See Adding a Mediation Extension for more information.

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When the API Gateway receives API invocation calls, it similarly contacts the API Key Manager service for verification. This verification call happens every time the Gateway receives an API invocation call if caching is not enabled at the Gateway level. For this verification, the Gateway passes access token, API, API version to the Key Manager.

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