An API gateway is the front door for an API. Every request from a client application passes through it before reaching backend services, giving external users a stable interface even when the internal architecture changes. section 8.4.1
In Azure API Management, the gateway works with a management plane and developer portal. The portal provides subscriptions and documentation; the management plane binds the service together; the gateway connects applications to APIs. Azure manages and hosts all three. section 8.4
A gateway earns its keep by:
- Hiding backend changes so teams can add features and fix bugs without forcing client applications to change their endpoints. section 8.4.1
- Connecting API consumers to backend integrations such as Azure Functions and HTTP-triggered Logic Apps. section 8.4.1 section 8.4.5
- Requiring an HTTP-accessible endpoint for integrations; a blob-triggered Logic App cannot connect directly as an API endpoint. section 8.4.5
A serverless API front door
A Logic App can receive an NFT ID through an HTTP query parameter, retrieve its image from Blob Storage, and post a tweet. Connecting that workflow to API Management exposes it through the gateway; authentication can be added for incoming requests. section 8.4.5
C: /> az apim create --name alpacaapim --resource-group AlpacaRG --publisher-name alpacamabags --publisher-email admin@alpacamabags.com --location australiaeast --sku-name consumption --no-wait
The Azure CLI command provisions an API Management instance with the Consumption tier and returns without waiting for completion. section 8.4
