Getting Started

This project is in its infancy, and does not yet have an installable package or distribution.

If you want to use it anyway, you can import it by specifying the desired commit hash in package.json, and then instruct Babel to transform node_modules/async-operations-manager.

A distributed package is currently planned for after the API has stabilized and test coverage is satisfactory.

Integration Guides

Name	README
Redux	`src/reduxIntegration/README.md`

Mission Statement:

async-operations-manager seeks to minimize the overhead of generating stateful data of an async request while also providing a system to improve data-fetching performance through async operation parent-child relationships and caching.

What is an Async Operation?

The idea is for an async operation is an object containing all of the metaData inherent to accurately represent the state of an async request. There are fundamentally two types of async operations; read and write.

const readAsyncOperation = {
  descriptorId: 'FETCH_EXAMPLE',
  // The fetch status of the async operation ('NULL' | 'PENDING' | 'SUCCESSFUL' | 'FAILED')
  fetchStatus: FETCH_STATUS.NULL,
  // The status of the data of an async operation ('ABSENT' | 'PRESENT')
  dataStatus: DATA_STATUS.ABSENT,
  // Any message returned as a response from the request
  message: null,
  // Date-time of the last time the async operation had a fetch status of 'SUCCESSFUL'
  lastFetchStatusTime: 0,
  lastFetchFailed: false,
  // Date-time of the last time the async operation had a data status of 'PRESENT'
  lastDataStatusTime: 0,
}

// The write async operation has no need to have dataStatus metaData since it does not
// involve fetching data
const writeAsyncOperation = {
  descriptorId: 'UPDATE_EXAMPLE',
  fetchStatus: FETCH_STATUS.NULL,
  message: null,
  lastFetchStatusTime: 0,
};

This metaData can be used to better optimize async requests to a server (lastFetchStatusTime, lastDataStatusTime, lastFetchFailed) and also provides an api to hook into when determining what visual feedback to present the user as the async request makes its journey (dataStatus and fetchStatus).

How to use Async Operations:

Everytime an async request completes a new stage of its journey we want to update the operation to reflect it's new state.

Async request journey:

Identify an async request is going to happen (a request to fetch all users)

const fetchAllEmployeesByStoreId = (storeId) => {
    // returns a promise
    return api.fetchAllEmployeesByStoreId(storeId);
};

import asyncOperationManager from 'async-operations-manager';
asyncOperationManager.registerAsyncOperationDescriptors(
  {
    descriptorId: 'FETCH_ALL_EMPLOYEES_BY_STORE_ID',
    requiredParams: ['storeId'],
    operationType: asyncOperationManager.ASYNC_OPERATION_TYPES.READ,
  },
);
const fetchAllEmployeesByStoreId = (storeId) => {
    // returns a promise
    return api.fetchAllEmployeesByStoreId(storeId);
};

Begin an async operation when you begin an async request (getStateForOperationAfterStep)

import asyncOperationManager from 'async-operations-manager';
asyncOperationManager.registerAsyncOperationDescriptors(
  {
    descriptorId: 'FETCH_ALL_EMPLOYEES_BY_STORE_ID',
    requiredParams: ['storeId'],
    operationType: asyncOperationManager.ASYNC_OPERATION_TYPES.READ,
  },
);

const fetchAllEmployeesByStoreId = (storeId) => {
    // transforms async operation to a begun state
    getStateForOperationAfterStep({}, asyncOperationManager.ASYNC_OPERATION_STEPS.BEGIN_ASYNC_OPERATION, 'FETCH_ALL_EMPLOYEES_BY_STORE_ID', { storeId: 2 })
    // returns a promise
    return api.fetchAllEmployeesByStoreId(storeId)
};

Resolve or Reject an async operation after an async response (server response?) is received (getStateForOperationAfterStep)

import asyncOperationManager from 'async-operations-manager';
asyncOperationManager.registerAsyncOperationDescriptors(
  {
    descriptorId: 'FETCH_ALL_EMPLOYEES_BY_STORE_ID',
    requiredParams: ['storeId'],
    operationType: asyncOperationManager.ASYNC_OPERATION_TYPES.READ,
  },
);

const fetchAllEmployeesByStoreId = (storeId) => {
    // transforms async operation to a begun state
    getStateForOperationAfterStep({}, asyncOperationManager.ASYNC_OPERATION_STEPS.BEGIN_ASYNC_OPERATION, 'FETCH_ALL_EMPLOYEES_BY_STORE_ID', { storeId: 2 })
    return api.fetchAllEmployeesByStoreId(storeId).then(response => {
            // transforms async operation to a resolved state
            getStateForOperationAfterStep({}, asyncOperationManager.ASYNC_OPERATION_STEPS.RESOLVE_ASYNC_OPERATION, 'FETCH_ALL_EMPLOYEES_BY_STORE_ID', { storeId: 2 })
            return response;
    }).catch(err => {
        // transforms async operation to a rejected state
        getStateForOperationAfterStep({}, asyncOperationManager.ASYNC_OPERATION_STEPS.REJECT_ASYNC_OPERATION, 'FETCH_ALL_EMPLOYEES_BY_STORE_ID', { storeId: 2 })
        return err
    ));
};

Async Operations Manager API

Config API

Name	Type	Description	Args
initializeWithOptions	Function	Set runtime config options for library	(config: { logger: Object })

State API

Name	Type	Description	Args
getAsyncOperationsManagerState	Function	Get current AOM state	None
clearAsyncOperationsManagerState	Function	Clear current AOM state	None
setAsyncOperationsManagerStatee	Function	Set current AOM state	None

Operation API

Name	Type	Description	Args
registerAsyncOperationDescriptors	Function	Register async operation descriptor(s)	(asyncOperationDescriptor(s): can be an array of descriptors or one descriptor object)
getAsyncOperation	Function	Get Async Operation from library state	(state: Object, descriptorId: String, params: Object, otherFields: Object)
getAsyncOperationDescriptor	Function	Get a Descriptor for an Async Operation from library state	(descriptorId: String)
getStateForOperationAfterStep	Function	Transform and return an Async Operation with a given step (Begin, Resolve, Reject)	(state: Object, asyncOperationStep: String, descriptorId: String, params: Object)
shouldRunOperation	Function	Return a bool if fetch Operation should be run according to the corresponding Operation's Descriptor's caching options	(descriptorId: String, params: Object)

Integration APIs

Name	README
reduxIntegration	`src/reduxIntegration/README.md`

sam1463/async-operations-manager