@onflow/interaction

This module provides an ADT (Abstract Data Type) that represents the underlying data required by the send function. It provides function in which to modify the interaction.

Status

• Last Updated: April 21st 2020
• Stable: Yes
• Risk of Breaking Change: Medium

This is a keystone data structure in how the SDK works. We will strive for backwards compatibility in any changes to this, as it also makes our lives easier. Now that we have a stable encoding package for creating what needs to be signed in transactions, we will be bringing this data structure closer to what those functions need.

Known Upcoming Changes:

• We will be changing some of the underlying fields and data so they are more inline with @onflow/encode

Install

npm install --save @onflow/interaction

Types of interactions

Currently the Access Node recognizes 7 different types of interactions.

• Script executes a script, can be used to query Flow
• Transaction executes a transaction
• GetTransactionStatus requests the status of a supplied transaction
• GetAccount requests a supplied account
• GetEvents requests events of a supplied type
• GetLatestBlock requests the latest block
• Ping requests a pong

Internal Properties

The interaction is a monomorphic data structure, that merges the 7 types of interactions together. Internally it has a bunch of properties, but not everything needs to be included for each of the 7 interaction types.

• tag (all) Int -- a marker that represents the type of the interaction
• status (all) Int -- a marker that represents the status of the interaction
• reason (all) String -- used to supply more information/feedback when a status is bad
• accounts (transaction, script)
  • kind (transaction, script) Int -- denotes the kind of account, ACCOUNT or PARAM
  • tempId (transaction, script) String -- denotes the internal tempId for this account
  • addr (transaction, script) String -- denotes the address of this account
  • keyId (transaction, script) Int -- denotes the keyId in question for this account
  • sequenceNum (transaction, script) Int -- denotes the sequenceNum in question for this account
  • signature (transaction, script) String -- the signature produced by the signingFunction for this account
  • signingFunction (transaction, script) Function -- the signing function for this account
  • resolve (transaction, script) Function -- the resolver for this account
  • role (transaction, script)
    • propser (transaction, script) Boolean -- denotes if this account is a propser
    • authorizer (transaction, script) Boolean -- denotes if this account is an authorizer
    • payer (transaction, script) Boolean -- denotes if this account is a payer
    • param (transaction, script) Boolean -- denotes if this account is a param
• params (transaction, script)
  • kind (transaction, script) Int -- denotes the kind of param, ACCOUNT or PARAM
  • tempId (transaction, script) String -- the internal tempId for this param
  • key (transaction, script) String -- the key for this param
  • value (transaction, script) Any -- the value for this param
  • xform (transaction, script) Any -- the transform for this param
  • resolve (transaction, script) Function -- a resolver for this param
• message (script, transaction)
  • cadence (script, transaction) String -- cadence code
  • refBlock (transaction) String -- id of an existing block (used for timeout)
  • computeLimit (script) Int -- how much payer is willing to spend
  • proposer (transaction) String -- the tempId of the account proposer for a transaction
  • payer (transaction) String -- the tempId of the payer for a transaction
  • authorizations (transaction) Array<String> -- list of tempIds referencing the accounts of the authorizers for a transaction
  • params (transaction, script) Array<String> -- list of tempIds referencing the params for a transaction
• proposer (transaction) String -- the tempId referencing the account of the proposer for a transaction
• payer (transaction) String -- the tempId referencing the account of the payer for a transaction
• authorizations (transaction) Array<String> -- list of tempIds referencing the accounts of the authorizers for a transaction
• events (getEvents)
  • start (getEvents) Int -- events after this
  • end (getEvents) Int -- events before this
  • eventType (getEvents) String -- type of events to get
• latestBlock _(getLatestBlock)
  • isSealed (getLatestBlock) Boolean Boolean -- determines if the criteria for the latest block is sealed or
• accountAddr (getAccount) String -- the account to get
• transactionId (getTransactionStatus) String -- the transaction to get
• assigns (all) {[String]:Any} -- a pocket to hold things in while building and resolving

Exposed Constants

Tags

Status

Exposed Functions

• Constructor
  • interaction/0
  • isInteraction/1
• Control
  • Ok/1
  • isOk/1
  • Bad/2
  • isBad/1
  • why/1
• Tags
  • Unknown
    • makeUnknown/1
    • isUnknown/1
  • Script
    • makeScript/1
    • isScript/1
  • Transaction
    • makeTransaction/1
    • isTransaction/1
  • GetTransactionStatus
    • makeGetTransactionStatus/1
    • isGetTransactionStatus/1
  • GetAccount
    • makeGetAccount/1
    • isGetAccount/1
  • GetEvents
    • makeGetEvents/1
    • isGetEvents/1
  • GetLatestBlock
    • makeGetLatestBlock/1
    • isGetLatestBlock/1
  • Ping
    • makePing/1
    • isPing/1
• Assigns
  • get/3
  • put/2
  • update/2
  • destroy/1
• Accounts
  • makeAuthorizer/1
  • makePayer/1
  • makeProposer/1
• Params
  • makeParam/1
• Composition
  • pipe/2
  • pipe/1

interaction/0

Constructs an empty interaction.

import {interaction} from "@onflow/interaction"

const emptyInteraction = interaction()

isInteraction/1

returns true if the value passed to it is an interaction

import {interaction, isInteraction} from "@onflow/interaction"

const ix = interaction()

isInteraction(ix) // true
isInteraction("i am a string") // false

Ok/1 and isOk/1

Sets the status of an interaction to OK

import {interaction, Ok, isOk} from "@onflow/interaction"

isOk(Ok(interaction())) // true

Bad/2, isBad/1 and why/1

Sets the status of an interaction to BAD, can also add a reason as to why its bad.

import {interaction, Bad, why} from "@onflow/interaction"

const ix = Bad(interaction, "You were supposed to do the thing")
isBad(ix) // true
why(ix) // "You were supposed to do the thing"

makeUnknown/1 and isUnknown/1

tags an interaction as Unknown

import {interaction, makeUnknown, isUnknown} from "@onflow/interaction"

isUnknown(makeUnknown(interaction())) // true

makeScript/1 and isScript/1

tags an interaction as a Script interaction

import {interaction, makeScript, isScript} from "@onflow/interaction"

isScript(makeScript(interaction())) // true

makeTransaction/1 and isTransaction/1

tags an interaction as a Transaction interaction

import {interaction, makeTransaction, isTransaction} from "@onflow/interaction"

isTransaction(makeTransaction(interaction())) // true

makeGetTransaction/1 and isGetTransaction/1

tags an interaction as a GetTransactionStatus interaction

import {
  interaction,
  makeGetTransactionStatus,
  isGetTransactionStatus,
} from "@onflow/interaction"

isGetTransactionStatus(makeGetTransactionStatus(interaction())) // true

makeGetAccount/1 and isGetAccount/1

tags an interaction as a GetAccount interaction

import {interaction, makeGetAccount, isGetAccount} from "@onflow/interaction"

isGetAccount(makeGetAccount(interaction())) // true

makeGetEvents/1 and isGetEvents/1

tags an interaction as a GetEvents interaction

import {interaction, makeGetEvents, isGetEvents} from "@onflow/interaction"

isGetEvents(makeGetEvents(interaction())) // true

makeGetLatestBlock/1 and isGetLatestBlock/1

tags an interaction as a GetLatestBlock interaction

import {
  interaction,
  makeGetLatestBlock,
  isGetLatestBlock,
} from "@onflow/interaction"

isGetLatestBlock(makeGetLatestBlock(interaction())) // true

makePing/1 and isPing/1

tags an interaction as a Ping interaction

import {interaction, makePing, isPing} from "@onflow/interaction"

isPing(makePing(interaction())) // true

get/3, put/2, update/2 and destory/1

crud operations for the assigns pocket inside the interaction. They are specifically designed to be used with pipe.

import {interaction, get, put, update, destory} from "@onflow/interaction"

let ix = interaction()
get(ix, "count", 0) // 0

ix = put("count", 0)(ix)
get(ix, "count", 0) // 0

ix = update("count", count => count + 1)(ix)
get(ix, "count", 0) // 1

ix = destory("count")(ix)
get(ix, "count", 0) // 0

makeAuthorizer/1

compose an Authorizer account, and registers a tempId for it in the interaction object accounts registry

import {makeAuthorizer, makeTransaction, pipe} from "@onflow/interaction"
const ix = pipe([
  makeTransaction``
  makeAuthorizer({ addr: "01", role: { authorizer: true } })
])

makePayer/1

compose a Payer account, and registers a tempId for it in the interaction object accounts registry

import {makePayer, makeTransaction, pipe} from "@onflow/interaction"
const ix = pipe([
  makeTransaction``
  makePayer({ addr: "01", role: { payer: true } })
])

makeProposer/1

compose a Proposer account, and registers a tempId for it in the interaction object accounts registry

import {makeProposer, makeTransaction, pipe} from "@onflow/interaction"
const ix = pipe([
  makeTransaction``
  makeProposer({ addr: "01", role: { proposer: true } })
])

makeParam/1

compose a Param, and registers a tempId for it in the interaction object params registry

import {makeParam, makeTransaction, pipe} from "@onflow/interaction"
const ix = pipe([
  makeTransaction``
  makeParam(...)
])

pipe/2

asynchronously composes transform functions and applys them to an interaction.

import {interaction, pipe, put, update} from "@onflow/interaction"

const ix = await pipe(interaction(), [
  put("a", 5),
  put("b", 6),
  update("sum", (_, ix) => get(ix, "a", 0) + get(ix, "b", 0)),
])

get(ix, "sum", 0) // 11

pipe/1

gets passed an array of transform functions, returning a function that takes an interaction to apply the transform functions to asynchronously.

import {interaction, pipe, put, update} from "@onflow/interaction"

const run = await pipe([
  put("a", 5),
  put("b", 6),
  update("sum", (_, ix) => get(ix, "a", 0) + get(ix, "b", 0)),
])

const ix = run(interaction())

get(ix, "sum", 0) // 11

// Pipes can also be composed

const p1 = pipe([put("a", 1), put("b", 2)])

const p2 = pipe([put("c", 3), put("d", 4)])

const calc = update("sum", (_, ix) =>
  ["a", "b", "c", "d"].reduce((acc, d) => acc + get(ix, d, 0), 0)
)

const ix = await pipe(interaction(), [p1, p2, calc])
get(ix, "sum", 0) // 10

// Pipes can be stoped

import {Bad, Ok, isBad, why} from "@onflow/interaction"

const countCantBeGreaterThan = value => ix =>
  get(ix, "count", 0) > value ? Bad(ix, `Was greater than ${value}`) : Ok(ix)

const setCount = count => put("count", count)

const incCountBy = amount => update("count", count => count + amount)

const ix = await pipe(interaction(), [
  setCount(5), // count: 5
  countCantBeGreaterThan(10), // Ok
  incCountBy(3), // count: 8
  countCantBeGreaterThan(10), // Ok
  incCountBy(5), // count: 13
  countCantBeGreaterThan(10), // Bad
  incCountBy(9), // never called
])

isBad(ix) // true
why(ix) // "Was greater than 10"