TIDE API

Utility to easily consume a rest api in a browser javascript project.

Getting started

To start using the library you should create an api object with the minimum config:

import Api from 'tide-api';

const config = {
                   host: "https://example.com",
                   endpoints: [
                       "users"
                   ]
               }

const api = new Api( config )

api.users.get(); //Promise resolves to the server's response of https://example.com/users

Config parameters

The configuration should be an object which could contain the following properties:

Property	type	Default	Description
appendHeaders	function	undefined	A function to modify the headers of each request. It will receive the headers created as first argument and it should modify this same object. The headers are in a plain object. The returned value is ignored
commonPath	string	empty string	The path to append to the host on each request. Example: if you use the config object {host:'http://example.com', commonPath:'api', endpoints:['users']} calling the method api.users.get() would generate the url http://example.com/api/users
createHeaders	function	function	The function to create the headers to send in each request. It is called with the options object sent to the apiCall as first argument. The options object contains an additional boolean property useFormData which may have been forced with the files parameter in an apiCall argument.
credentials	string	"omit"	Set the credentials parameter of the request. See available options
endpoints (required)	array	-	An array describing each endpoint, see next section for endpoints' description format
getDataFromResponse	function	(response)=>response	Before storing the result to redux, this method will be called and its result will be stored. The default method returns the same data like: ( response, headers )=>response
getMetaDataFromResponse	function	()=>undefined	To extract meta data from the response ( like page, total items, etc. ), then the returned object will be stored in redux with the key {endpointName}Meta. The method has the signature (response, headers)=>object
host (required)	string	-	The url to which the request will be done. It should contain the protocol.
localStorageKey	string	"api"	The key to use in the local storage to save log-in state and cache data
login	object		For login usage and configuration see the login section
nameToPath	function	See description	A function to create the api path from the endpoint name given in the endpoint configuration. By default it converts from camel case to snake case. e.g. ( "personProfile" ) => "person_profile"
parseJson	boolean	true	If true and the server response has "content-type: json", the response will be parsed before resolving the api's promise
queryStringOptions	object	{ arrayFormat: 'brackets' }	Options for converting the request parameters to a GET query string. See qs for available options.
queueInterval	integer	180000	Time in milliseconds between each intent to resend a request when it is queued
reduxStore	object	undefined	The redux store to dispatch endpoints actions. See Redux to know how to use it
saveTokenToLocalStorage	boolean|"safari"	false	Whether to save the authentication token to local storage or not. See Why to do that.
strictMode	boolean	true	If set to false, any endpoint could be called without defining it in the endpoints array. It will be called as if it were defined as a string.
tokenKey	string	"tideApiToken"	The key to use in the local storage to save the token
useSessionStorage	boolean	false	If false the default storage will be localStorage if true it will be sessionStorage. The use of sessionStorage in combination with saveTokenToLocalStorage will create more secure ephemeral sessions which disappears when the tab is closed

Endpoint configuration

The available endpoints in the api should be defined in the endpoints property of the main config object. An endpoint can be defined in two ways:

Define an endpoint as a string

If an endpoint from the endpoints array is a string, an automatic endpoint will be created with the following methods: create, get, update and delete.
This endpoint will be a property of the api object, here's an example of how to use it:

const api = new API( {
    host: "https://example.com",
    endpoints: [
        "users"
    ]
} );

console.log( api.users );//{ create: fn, get: fn, update: fn, delete: fn }

api.users.get() // Promise
    .then( users=>{
        //Use the users returned from the server
     })
     
api.users.create( endpointArguments ) // Promise
    .then( user=>{
        //Use the created user returned from the server
     })

Like that you could use any of the methods automatically defined and a promise which resolves to the server response ( already parsed if it's a json ) will be returned.

The default endpoints accept an endpointArguments object, which may have any of the following properties:

name	type	description
credentials	string	Overrides the credentials parameter of the request set in the global configuration.
customProp	string	For redux integration. This changes the name with which the response will be saved to redux. By default it's the same as the endpoint's name
files	object	Files to append to the request. They are ignored if method is set to "GET". If set, the option useFormData is always set to true. It could be a File object in which case will be sent with the property name set to "file". It could be an Array in which case al files will be appended with a property name of "files[]". It could be and object where every file will be appended with a property name of the key inside the object that corresponds. ( objects are not recursively appended )
id	string	The methods get, update and delete can receive an id which will be appended to the end of the url to call. e.g.( api.users.delete({id:30}) would make a DELETE call to the endpoint /api/users/30. The id is mandatory for the update and delete methods.
method	string	The request method to use, the default depends on the endpoint type as follows, get -> "GET", create -> "POST", update -> "PUT", delete -> "DELETE"
params	object	Info to send to the server. In GET requests, params are sent as query string, in all the other methods they're sent as a json in the request body.
stateAction	string	This says how to modify redux's state. See redux section for available options
useFormData	boolean	Default to false. If true, the params are sent with FormData formatting in the request body. This is ignored if the method is set to "GET". This is enforced if the files property is set.

Also, any configuration found in the Config parameters section can be used in this object to override it for a single call.

Define an endpoint as an object

If you want to customize the endpoint's behavior you could send an object to change any part of the request made. The object should have a name property which will be used to create the url as if it where a "string" defined endpoint. The endpoint object can have any of the following properties:

Property	type	Default	Description
customMethods	object	undefined	An object of functions which will be merged to the endpoint object. e.g. using the definition {name:'users', customMethod:{activate:function(){}}} will make this method available as api.users.activate()
preventDefaultMethods	boolean	false	If it's true a method denied as {name:'users'} will also have de default methods get, create, update and delete. Otherwise it will not have this methods available

Also, any configuration found in the Config parameters section can be used in this object to override it for a single endpoint.

Login

There's a default login implementation based on making a login request, saving the received token (if it's not saved as a cookie already), and persisting it to the local storage (or session storage if useSessionStorage is set).
To attempt a login just call the login() method of an api object, like:

const api = new Api(apiConfig);
api.login( user, password)

Afterwards you can start to make other api calls, and the login state should remain until expired o manually logged out.
The available login configuration that could be sent in the login key of the main config object is the following:

name	type	default	description
path	string	"login_check"	The path to append to the url to make the login request
method	string	"POST"	Http method to use in the request
createBody	function	(username, password)=>FormData	The function to create the request body. This function receives the same arguments sent when calling api.login(). By default the function creates a FormData object appending the first argument with the key _username and the second argument as _password
parseJson	boolean	true	Whether to try to parse the response before returning the promise
tokenExtractor	function	(json)=>json.token	The function to extract the login token information from the response. If parseJson is set to true, this will receive the parsed response, otherwise it will receive the response object. It should return the token string

Authentication tokens and local storage

Most servers send their authentication identifier as a cookie. However, newer browsers are starting to prevent cookies from being saved when they are cross-origin. This makes us impossible to log in to an API hosted in a different domain than our front-end.

To solve this the server must send the authentication token in the log-in request's body, then we save it and append it to every request we do afterwards, be it as a header, in the query string or as a header.

If saveTokenToLocalStorage is set to true the token will be sent as a header to the server like this:

 Authorization: Bearer {token}

TODO: Create a configuration to set how is the token sent, change header format or append it to other request part.

Redux

There's a default integration with redux which can be activated just passing the store to the constructor with the reduxStore property.

If you want to use redux, you need to include the api's reducer in to your store's root reducer. Here's an example:

 //rootReducer.js
 import { combineReducers } from 'redux';
 import {reducer, loadingReducer, loadingByIDReducer } from 'tide-api';
 
 const rootReducer = combineReducers({
 
     api: reducer
     loading: loadingReducer,
     loadingIds: loadingByIDReducer,
     // ... your other reducers
 });
 
 export default rootReducer;

This would generate three properties in your state:

• api: This is an object where all your endpoints' data will be saved. Each endpoint has its property, let's say you have an users endpoint, after the promise returned by api.users.get() is finished, the state would change and you could find in there the data returned by the server like: state.api.users That would be an array with the users objects.
• loading: this is an integer with the count of pending requests, this could be used for a global loading indicator. If it's zero, then nothing is loading, if it's anything other than zero, then there are some requests pending.
• loadingIds: this is like the loading indicator but for individual endpoint calls. To use this you should send a loadingId string to an endpoint call like:
  api.users.get( {loadingId:"usersView"} ) after this there will appear this property in the redux state with the count of pending requests with this specific loadingId. So after that call and before the request is finished, you would find your state like this: state.loadingIds.usersView // 1.

Redux state actions

TODO: Write this section

Cache

Right now the cache is only for when we lose connection, it's no for preventing requests to the server.
TODO: Implement a cache to prevent server requests

If an endpoint is cacheable the response will be stored in the local storage every time we receive a server response. Afterwards, if we call the same endpoint and the request fails, the api will complete the promise as if it had succeded with the data from the cache.