@ethersana/ant-js/src/modules/feed.ts

Javascript client for Ant

import { BatchId, Dictionary, Reference, ReferenceResponse, Topic } from '../types'
import { safeAxios } from '../utils/safe-axios'
import { FeedType } from '../feed/type'
import { HexEthAddress } from '../utils/eth'
import { extractUploadHeaders } from '../utils/headers'

const feedEndpoint = '/feeds'

export interface CreateFeedOptions {
  type?: FeedType
}

export interface FeedUpdateOptions {
  /**
   * Specifies the start date as unix time stamp
   */
  at?: number
  /**
   * Can be 'epoch' or 'sequence' (default: 'sequence')
   */
  type?: FeedType
}

interface FeedUpdateHeaders {
  feedIndex: string
  feedIndexNext: string
}
export interface FetchFeedUpdateResponse extends ReferenceResponse, FeedUpdateHeaders {}

/**
 * Create an initial feed root manifest
 *
 * @param url             Bee URL
 * @param owner           Owner's ethereum address in hex
 * @param topic           Topic in hex
 * @param postageBatchId  Postage BatchId to be used to create the Feed Manifest
 * @param options         Additional options, like type (default: 'sequence')
 */
export async function createFeedManifest(
  url: string,
  owner: HexEthAddress,
  topic: Topic,
  postageBatchId: BatchId,
  options?: CreateFeedOptions,
): Promise<Reference> {
  const response = await safeAxios<ReferenceResponse>({
    method: 'post',
    url: `${url}${feedEndpoint}/${owner}/${topic}`,
    params: options,
    headers: extractUploadHeaders(postageBatchId),
  })

  return response.data.reference
}

function readFeedUpdateHeaders(headers: Dictionary<string>): FeedUpdateHeaders {
  return {
    feedIndex: headers['swarm-feed-index'],
    feedIndexNext: headers['swarm-feed-index-next'],
  }
}

/**
 * Find and retrieve feed update
 *
 * The feed consists of updates. This endpoint looks up an
 * update that matches the provided parameters and returns
 * the reference it contains along with its index and the
 * index of the subsequent update.
 *
 * @param url         Bee URL
 * @param owner       Owner's ethereum address in hex
 * @param topic       Topic in hex
 * @param options     Additional options, like index, at, type
 */
export async function fetchFeedUpdate(
  url: string,
  owner: HexEthAddress,
  topic: Topic,
  options?: FeedUpdateOptions,
): Promise<FetchFeedUpdateResponse> {
  const response = await safeAxios<ReferenceResponse>({
    url: `${url}${feedEndpoint}/${owner}/${topic}`,
    params: options,
  })
  const findFeedUpdateResponse = {
    ...response.data,
    ...readFeedUpdateHeaders(response.headers),
  }

  return findFeedUpdateResponse
}