Sarvis NPM | npm.io

Sarvis

Sarvis is a simple, small api that helps organise and execute your HTTP requests with excellent Typescript support. build on top of the browser native fetch api.

Using Sarvis

To create a new instance of Sarvis:

const sarvis = new Sarvis();

It's possible to pass a base configuration to Sarvis:

const sarvis = new Sarvis({
    // The url that will be used in every request.
    base_url: "https://www.your-domain.com",
    // (Optional) The port number that will be used for a request.
    port: 3000,
    // (Optional) Most api's have a base path, such as: /api, or /v1 etc.
    base_path: "/api",
    // (Optional) A string that will be set to the Authorazation header on every request, for example:
    // "Bearer YOUR_BEARER_TOKEN_HERE".
    authorization: "Bearer a_token_here"
});

// You can access and update the configuration through sarvis.config:
const config: ISarvisConfig = sarvis.config;

// Let's update the authorization for example:
sarvis.config.authorization = "Bearer a_token_here";

Requests

GET

Let's say we're fetching a TODO item that looks like this:

{
  "id": 1,
  "todo": "Clean Kitchen" 
}

And we have an Interface declared for this dto:

interface TodoDto {
    id: number;
    todo: string;
}

Let's perform a GET request for that Todo:

const result = await sarvis.get<TodoDto>("https://www.your-domain.com/api/1");

Your result object is now of type TodoDto.

If you have added a config with base_url, you only need to add the part that comes after:

const result = await sarvis.get("/1");

POST, PUT, DELETE

For all other requests, add a body after the URL:

const postResult = await sarvis.post<TodoDto>("/1", body);

const putResult = await sarvis.put<TodoDto>("/1", body);

// The body for a DELETE request is optional.
const deleteResult = await sarvis.post<boolean>("/1", body);

Custom Configuration

You won't of course, always want to use the standard request configuration. It's possible to add a custom configuration to every request:

const customConfig: RequestInit = {
    method: "POST",
}
const result = await sarvis.get("/1", customConfig);

useBefore and useAfter

Sometimes you want to execute an operation before, or after evey request. Sarvis offers an easy way to do so:

// Executed before every request.
sarvis.useBefore = (url: string, config: RequestInit) => {
    url = url + "/todos";
    config.headers.append("Content-Type", "blob");
    
    return { url, config };
};

// Executed after every request, if returnFullRequest is set to true, it will return the full Request object.
sarvis.useAfter = (result: any) => {
    result["newValue"] = "Some Test value for demo purposes.";

    return result;
};

Get the Request before JSON conversion

By default, request results are converted to JSON and then given back to the user. Of course not all request have a return type of JSON, or perhaps you want to have a look at the complete response.

To turn off JSON conversion for all Requests, set: