The architecture of the API Sentence app

First of all, before we delve into the lab, it is essential to understand how the API Sentence app is split between micro-services.

This is what the API Sentence website Frontend looks like when all the necessary micro-services are up and running:

Behind the scenes, the Frontend app reaches a Generator micro-service. The Generator micro-service reaches four distinct Words micro-services. Each Words micro-service generates a distinct word (an adjective, an animal, a color and a location).

Each Words micro-service is a NodeJS API server. This means we can GET, POST, PATCH, and DELETE each respective Words micro-service. The Frontend is just a web interface representing the outcomes of the APIs.

And this is how the micro-services mesh together

We can request each endpoint separately:

• Frontend -> Displays the web interface with the generated sentence.
• Generator -> Responds with a JSON payload and four words (one for each Words micro-service).
• Adjectives -> Responds with an adjective.
• Animals -> Responds with an animal.
• Colors -> Responds with a color.
• Locations -> Responds with a location.

A direct API call to a Words micro-service (like /animals) will provide a JSON response as below:

[
   {
      "id": 1,
      "name": "lion"
   },
   {
      "id": 2,
      "name": "whale"
   },
   {
      "id": 3,
      "name": "mouse"
   }
]

A direct API call to the Generator micro-service will provide a JSON response as below:

{
   "adjectives": "kind",
   "animals": "mouse",
   "colors": "black",
   "locations": "park"
}

From the previous example, this is how the sentence is generated when the Generator micro-service requests the 4 words:

Note

In this lab, in order to simplify steps not related to NMS ACM, the Sentence App is already up and running in version 1 (color WORD is not deployed).