**I'm happy to finally introduce version 2.0 of *steemconnect-firebase-funtions*, which brings the library to a next level. I hope that changes described in this contribution and in my [previous one](https://utopian.io/utopian-io/@jakipatryk/road-to-steemconnect-firebase-functions-2-0-0-what-has-been-done-so-far) will make development of apps built with Firebase and SteemConnect easier.**

![](https://cdn.utopian.io/posts/09b3235d4c2aa51887ac16db167951b4112aimage.png)

### Quick recap

**steemconnect-firebase-functions** is a TypeScript library that can help you build applications with SteemConnect and Firebase. The library makes it easy to:

- **implement** OAuth2 Authorization Code Grant
- **broadcast** operations to the Steem blockchain
- **check** OAuth2 error types
- **mint** Firebase Custom Tokens
- **create** Firebase Auth accounts for your users with additional data
- **store** tokens in the Firebase Cloud Firestore

#### Links:

- Github: https://github.com/jakipatryk/steemconnect-firebase-functions
- SteemProjects: https://steemprojects.com/projects/p/steemconnect-firebase-functions/
- NPM: https://www.npmjs.com/package/steemconnect-firebase-functions

### New documentation

For version 2.0, I've made new documentation. The new one is available [here](https://jakipatryk.github.io/steemconnect-firebase-functions/).

More on that in my next contribution.

### New features

#### `rely` for reliable broadcasting

Most of the changes in my previous contribution were made to make the function `rely` possible to be built. For that, I introduced a few concepts. But what does `rely` do anyway?

SteemConnect's `access_token` **expires** 7 days after issuing. If your app didn't use server-side authentication, your user would have to refresh the access token himself by logging into SteemConnect once again.

But it is not the case when you use OAuth2 authorization code grant with `offline` scope. During this OAuth2 flow you get, along with `access_token`, another token called `refresh_token`, which doesn't expire and lets you refresh the access token.

##### How should the `refresh_token` be used? 

In my opinion, if a request to the SteemConnect service fails cause of expired `access_token`, the `refresh_token` should be used to get a new `access_token` and the request should be repeated.

The `rely` function does exactly that .

First of all, it wrapps a [**broadcastable**](https://jakipatryk.github.io/steemconnect-firebase-functions/getting-started/#broadcastable) function, client credentials, and a `AccessTokenResponse` object (with properties: `access_token`, `refresh_token`, `username`, `expires_in`).

Next, it tries to broadcast the [**broadcastable**](https://jakipatryk.github.io/steemconnect-firebase-functions/getting-started/#broadcastable) with provided `access_token`.

If the request is successful, it simply returns the result of broadcast. If it's not, it checks if the error is caused by expired `access_token` and if so, it refreshes it using provided `refresh_token`.

The request is being sent once again, this time with new `access_token`, and if successful, the `rely` function returns the result of broadcast along with new tokens.

##### Example usage

```typescript
import {
  rely,
  broadcastUpvote,
  Vote,
  AccessTokenResponse,
  ClientCredentials
} from 'steemconnect-firebase-functions';

const clientCredentials: ClientCredentials = {
  clientId: 'strimi.app',
  clientSecret: '432rnj3nr23nkvfdvdf'
};
const accessToken: AccessTokenResponse = {
  access_token: 'fdsfertre',
  expires_in: 4323432,
  username: 'jakipatryk',
  refresh_token: '3rk3m2krl3'
};
const voteOptions: Vote = {
  author: 'ned',
  permlink: 'i-am-ned',
  weight: 10000
};

const broadcastableUpvote = broadcastUpvote(voteOptions);

rely(clientCredentials)(accessToken)(broadcastableUpvote).then(response =>
  console.log(response)
);
//  {
//    result: { ... }
//    access_token: 'new access token if refreshed, otherwise undefined`
//    refresh_token: 'new refresh token if refreshed, otherwise undefined'
//    username: ...
//    expires: ...
//  }
```

For more, check the [documentation](https://jakipatryk.github.io/steemconnect-firebase-functions/broadcasting/#rely) and [implementation](https://github.com/jakipatryk/steemconnect-firebase-functions/blob/master/src/broadcasting/rely.ts).

#### Autocompleting author of operation

I changed the behavior of functions from *broadcasting* module.

As they require the entire `AccessTokenResponse` object as a parameter, so I decided to always autocomplete the author of operation with `username` property of `AccessTokenResponse`.

##### Example

```typescript
import {
  broadcastFollow,
  Follow,
  AccessTokenResponse
} from 'steemconnect-firebase-functions';

const followConfig: Follow = {
  userToFollow: 'jakipatryk'
};
const accessToken: AccessTokenResponse = {
  access_token: 'kj3n4jn2342.432p4k2p',
  expires_in: 640000,
  username: 'ned'
};

broadcastFollow(followConfig)(accessToken).then(response =>
  console.log(response)
);
//  {
//    result: { ... }
//  }
```

#### `AccessTokenResponse` everywhere

I decided to require the entire `AccessTokenResponse` object for every function which needs either `access_token` or any other properties.

I think it limits confusion, before this change, `accessToken` sometimes referred to the `access_token` string, sometimes to the object `AccessTokenResponse`.

#### `Scope` type

For better developer experience, I've added a `Scope` type:

```typescript
export type Scope =
  | 'login'
  | 'offline'
  | 'vote'
  | 'comment'
  | 'comment_options'
  | 'custom_json'
  | 'delete_comment'
  | 'claim_reward_balance';
```

#### `delete_comment` operation

Last but not least new feature in 2.0 is a support for `delete_comment` operation, which allows to delete a comment or post.

I've added the operation creator [`createDeleteComment`](https://jakipatryk.github.io/steemconnect-firebase-functions/operation-creators/#createdeletecomment), the broadcastable creator [`createBroadcastableDeleteComment`](https://jakipatryk.github.io/steemconnect-firebase-functions/shared/#createbroadcastabledeletecomment), and broadcast function [`broadcastDeletion`](https://jakipatryk.github.io/steemconnect-firebase-functions/broadcasting/#broadcastdeletion).

### How to contribute?

##### Do you have a question? 

Feel free to contact me on **Discord** (jakipatryk#1263) or on **Steem.chat** (jakipatryk).

##### Have you found a bug?

Publish a Utopian contribution and add an Issue to the project on Github!

###### Do you want to write some code?

Fork the repo, do your changes and create a pull request!

### Pull requests
- https://github.com/jakipatryk/steemconnect-firebase-functions/pull/43
- https://github.com/jakipatryk/steemconnect-firebase-functions/pull/46
- https://github.com/jakipatryk/steemconnect-firebase-functions/pull/48
- https://github.com/jakipatryk/steemconnect-firebase-functions/pull/53
- https://github.com/jakipatryk/steemconnect-firebase-functions/pull/44


<br /><hr/><em>Posted on <a href="https://utopian.io/utopian-io/@jakipatryk/36gter-reliable-broadcasting-steemconnect-firebase-functions-v2-0-is-here">Utopian.io -  Rewarding Open Source Contributors</a></em><hr/>