chore: Update README.md

README.md

@@ -1,13 +1,13 @@
 # Typoas
 
-![npm](https://img.shields.io/npm/v/@typoas/cli?label=cli%40npm)
-![npm](https://img.shields.io/npm/v/@typoas/generator?label=generator%40npm)
-![npm](https://img.shields.io/npm/v/@typoas/runtime?label=runtime%40npm)
-![GitHub](https://img.shields.io/github/license/embraser01/typoas)
+![npm](https://img.shields.io/npm/v/@typoas/cli?label=cli%40npm)  
+![npm](https://img.shields.io/npm/v/@typoas/generator?label=generator%40npm)  
+![npm](https://img.shields.io/npm/v/@typoas/runtime?label=runtime%40npm)  
+![GitHub](https://img.shields.io/github/license/embraser01/typoas)  
 ![npm bundle size](https://img.shields.io/bundlephobia/minzip/@typoas/runtime)
 
-Typoas is an OpenAPI 3.X generator for Typescript. It's inspired by [openapi-generator](https://openapi-generator.tech/)
-but is written in Typescript for Typescript. The generator uses the Typescript AST to generate code instead on relaying
+Typoas is an OpenAPI 3.X generator for Typescript. It's inspired by [openapi-generator](https://openapi-generator.tech/)  
+but is written in Typescript for Typescript. The generator uses the Typescript AST to generate code instead on relaying  
 on templates which allows better schemas definitions and other cool stuff.
 
 Main features are:
@@ -24,7 +24,7 @@ Main features are:
 - Small bundle size
 - And more...
 
-> <sup>1</sup>: OAuth2 scheme does not handle flows to retrieve an `accessToken`.
+> <sup>1</sup>: OAuth2 scheme does not handle flows to retrieve an `accessToken`.  
 > You need to provide your own `accessToken` through the `provider.getConfig()` function.
 
 The project is split into 3 parts:
@@ -33,16 +33,35 @@ The project is split into 3 parts:
 - [`@typoas/cli`](./packages/typoas-cli) is a CLI entry point built on top of `@typoas/generator`.
 - [`@typoas/runtime`](./packages/typoas-runtime) is the package that will be used by the generated code.
 
+---
+
+- [Installation](#installation)
+- [Usage](#usage)
+  - [Use the generator from the CLI](#use-the-generator-from-the-cli)
+  - [Use the generator from the API](#use-the-generator-from-the-api)
+  - [Use the generated code](#use-the-generated-code)
+    - [Customize server configuration](#customize-server-configuration)
+    - [Customize fetch implementation](#customize-fetch-implementation)
+    - [Handling authentification](#handling-authentification)
+    - [Customizing the serialization](#customizing-the-serialization)
+- [Examples](#examples)
+- [Notes](#notes)
+  - [External references](#external-references)
+  - [Parameters serialization](#parameters-serialization)
+  - [Migrating from v1 to v2](#migrating-from-v1-to-v2)
+- [Contributing](#contributing)
+- [License](#license)
+
 ## Installation
 
-It will generate a single TS file containing all the code specific to the underlying API.
-This file only has a single dependency on `@typoas/runtime`.
-**You need to manually** add `@typoas/runtime` to your `dependencies`.
+It will generate a single TS file containing all the code specific to the underlying API.  
+This file only has a single dependency on `@typoas/runtime`.  
+**You need to manually** add `@typoas/runtime` to your `dependencies`.  
 It handles common things like serialization/authentification
 
 ## Usage
 
-### Ues the generator from the CLI
+### Use the generator from the CLI
 
 You can generate the TS client from the spec from the command line:
 
@@ -57,14 +76,13 @@ Here is a short list of supported command line options:
     -i, --input [path/url]         Path or URL to the OpenAPI JSON specification (yaml/json format)
     -o, --output [path]            Path where to write the generated TS file
     -e,--generate-enums            Generate enums instead of literal string types where possible
+    -p,--prettier                  If set, the generated file will be formatted with Prettier
     --js-doc, --no-js-doc          Whether to add JS Doc to the generated code (default: true)
     --wrap-lines-at                Define a maximum width for JS Doc comments, 0 to disable (default: 120)
     --only-types                   Use it to only generate types in #components/schemas/
     --no-fetcher-options           Use it to disable the additional param added to every operations
     --version                      Output the version number
     -h, --help                     Display help for command
-
-    -n, --name                     Deprecated, name isn't used anymore
 ```
 
 or you can use it in code:
@@ -126,7 +144,113 @@ pullsList(ctx, {
   .catch((err) => console.error('Error while getting PRs', err));
 ```
 
-> The default `fetch` implementation is used (included in Node.js >= 18.0.0). You can always override the default fetch implementation in `createContext`
+You can customize multiple things in the `createContext` function.
+
+#### Customize server configuration
+
+By default, the `createContext` function will use the first `servers` entry in the spec.
+You can override the server configuration by passing a `ServerConfiguration` object:
+
+```typescript
+import { ServerConfiguration } from '@typoas/runtime';
+import { createContext } from './client';
+
+const ctx = createContext({
+  server: new ServerConfiguration('https://{env}.api.example.com', {
+    env: 'staging',
+  }),
+});
+```
+
+> The way it's done currently is not the best. It will be improved in the future.
+
+#### Customize fetch implementation
+
+The default fetcher implementation [uses](./packages/typoas-runtime/src/fetcher/index.ts) the `fetch` API.
+You can override the fetcher implementation if you want to customize things (like adding a retry policy, headers, etc.).
+
+For example, you can use `axios` instead of the `fetch` API:
+
+```typescript
+import axios, { AxiosError, AxiosResponse, Method } from 'axios';
+import { Fetcher, RequestContext, ResponseContext } from '@typoas/runtime';
+import { createContext } from './client';
+
+class AxiosHttpLibrary implements Fetcher {
+  async send(request: RequestContext): Promise<ResponseContext> {
+    let resp: AxiosResponse;
+    try {
+      resp = await axios.request({
+        url: request.getUrl(),
+        method: request.getHttpMethod() as Method,
+        headers: request.getHeaders(),
+        data: request.getBody(),
+      });
+    } catch (e) {
+      const err = e as AxiosError;
+      if (!err.response) {
+        throw e;
+      }
+      // Typoas handles errors itself
+      resp = err.response;
+    }
+
+    return new ResponseContext(resp.status, resp.headers, {
+      text: async () => resp.data as string,
+      binary: async () => resp.data as Blob,
+      json: async () => resp.data,
+    });
+  }
+}
+
+const ctx = createContext({ fetcher: new AxiosHttpLibrary() });
+```
+
+> Node.js >= 18.0.0 includes the `fetch` implementation, so Typoas should work out of the box.
+
+#### Handling authentification
+
+The `createContext` function can take an `authProviders` object to handle authentification.
+
+For example, for the petstore sample:
+
+```typescript
+import { createContext } from './petstore';
+
+const ctx = createContext({
+  authProviders: {
+    api_key: {
+      async getConfig() {
+        return 'MyAPIKey';
+      },
+    },
+    petstore_auth: {
+      getConfig() {
+        const accessToken = globalStore.getAccessToken();
+
+        if (accessToken) {
+          return null;
+        }
+        return { accessToken };
+      },
+    },
+  },
+});
+```
+
+It supports 4 types of security schemes:
+
+- `apiKey` mode
+- `http` bearer and basic mode
+- `oauth2` mode
+
+The `getConfig` function should return the configuration needed to authenticate the request. Returning `null` will skip the authentification.
+
+#### Customizing the serialization
+
+You can switch some serialization options by passing a `serializerOptions` object to the `createContext` function.
+
+> Not every serialization option is supported. See [#11](https://github.com/Embraser01/typoas/issues/11) for more information.
 
 ## Examples
 
@@ -138,7 +262,7 @@ Here is some notes on some known issues.
 
 ### External references
 
-External references are not supported. Every `$ref` must be in the spec.
+External references are not supported. Every `$ref` must be in the spec.  
 An issue is open [here](https://github.com/Embraser01/typoas/issues/37).
 
 ### Parameters serialization
@@ -150,13 +274,13 @@ _Typoas_ has partial support for serialization specified here: https://swagger.i
 - It **does NOT** support serialization for **query** parameters with nested objects. It will be JSON.stringify
 - It **does NOT** support serialization for **headers** or **cookie** parameters.
 
-On query serialization, there can only be one style for a full operation. The first query param will set the style for
+On query serialization, there can only be one style for a full operation. The first query param will set the style for  
 the whole operation.
 
 ### Migrating from v1 to v2
 
-In v1, the whole API was generated in a single class. In V2 this was replaced by individual function
-which allow [Tree Shaking](https://webpack.js.org/guides/tree-shaking/). To get a similar result,
+In v1, the whole API was generated in a single class. In V2 this was replaced by individual function  
+which allow [Tree Shaking](https://webpack.js.org/guides/tree-shaking/). To get a similar result,  
 you can use `wrapApi` helper:
 
 ```typescript