modules.format.encodeName() replacement in 20.0.0?

Question

In [email protected] I have a Eos.modules.format.encodeName()

Is there something like that in [email protected] or what can I use to replace it?

Answer 1

This module is often used in conjunction with get_table_rows(). If this is the case, you no longer need to encode names when making requests to this method. Simply pass the key as part of the lower_bound parameter.

For example you may make a request like this:

const resp = await rpc.get_table_rows({
  json: true,              // Get the response as json
  code: 'eosio',     // Contract that we target
  scope: 'eosio',         // Account that owns the data
  table: 'deposits',        // Table name
  lower_bound: 'ACCOUNT_NAME_HERE',   
  limit: 1               // Maximum number of rows 
});

Answer 2

I was looking for the same, so I just took the code from eosjs 16.0.9

Just put it in your project, and use it. The logic hasn't changed and won't ever change.

/**
  Encode a name (a base32 string) to a number.

  For performance reasons, the blockchain uses the numerical encoding of strings
  for very common types like account names.

  @see types.hpp string_to_name

  @arg {string} name - A string to encode, up to 12 characters long.
  @arg {string} [littleEndian = true] - Little or Bigendian encoding

  @return {string<uint64>} - compressed string (from name arg).  A string is
    always used because a number could exceed JavaScript's 52 bit limit.
*/
function encodeName(name, littleEndian = true) {
  if(typeof name !== 'string')
    throw new TypeError('name parameter is a required string')

  if(name.length > 12)
    throw new TypeError('A name can be up to 12 characters long')

  let bitstr = ''
  for(let i = 0; i <= 12; i++) { // process all 64 bits (even if name is short)
    const c = i < name.length ? charidx(name[i]) : 0
    const bitlen = i < 12 ? 5 : 4
    let bits = Number(c).toString(2)
    if(bits.length > bitlen) {
      throw new TypeError('Invalid name ' + name)
    }
    bits = '0'.repeat(bitlen - bits.length) + bits
    bitstr += bits
  }

  const value = Long.fromString(bitstr, true, 2)

  // convert to LITTLE_ENDIAN
  let leHex = ''
  const bytes = littleEndian ? value.toBytesLE() : value.toBytesBE()
  for(const b of bytes) {
    const n = Number(b).toString(16)
    leHex += (n.length === 1 ? '0' : '') + n
  }

  const ulName = Long.fromString(leHex, true, 16).toString()

  // console.log('encodeName', name, value.toString(), ulName.toString(), JSON.stringify(bitstr.split(/(.....)/).slice(1)))

  return ulName.toString()
}

/**
  @arg {Long|String|number} value uint64
  @arg {string} [littleEndian = true] - Little or Bigendian encoding

  @return {string}
*/
function decodeName(value, littleEndian = true) {
  value = ULong(value)

  // convert from LITTLE_ENDIAN
  let beHex = ''
  const bytes = littleEndian ? value.toBytesLE() : value.toBytesBE()
  for(const b of bytes) {
    const n = Number(b).toString(16)
    beHex += (n.length === 1 ? '0' : '') + n
  }
  beHex += '0'.repeat(16 - beHex.length)

  const fiveBits = Long.fromNumber(0x1f, true)
  const fourBits = Long.fromNumber(0x0f, true)
  const beValue = Long.fromString(beHex, true, 16)

  let str = ''
  let tmp = beValue

  for(let i = 0; i <= 12; i++) {
    const c = charmap[tmp.and(i === 0 ? fourBits : fiveBits)]
    str = c + str
    tmp = tmp.shiftRight(i === 0 ? 4 : 5)
  }
  str = str.replace(/\.+$/, '') // remove trailing dots (all of them)

  // console.log('decodeName', str, beValue.toString(), value.toString(), JSON.stringify(beValue.toString(2).split(/(.....)/).slice(1)))

  return str
}