chainview

Documentation

Overview

Package chainview answers, from the network's own words and the node's view of outputs, whether a transaction can still mine: what a settlement leg's error means, and which input another transaction spent, in words over bcommon's view of the node (nodeapi.Asset.SpentElsewhere). A sender's sweep and a payee's payment both need it, since a leg that accepted a transaction (arcade has answered ACCEPTED_BY_NETWORK for a transaction whose input was already spent and mined) or that answers nothing (the tcp ingress) cannot be taken at its word.

Index

• func RefusedAnswer(err error) (string, bool)
• func SpentElsewhere(ctx context.Context, a *nodeapi.Asset, tx *transaction.Transaction) string

Examples

• RefusedAnswer

Functions

func RefusedAnswer

func RefusedAnswer(err error) (string, bool)

RefusedAnswer reports whether a settlement leg's error is the network's definitive refusal of these bytes, and in what words:

• arcade's verdict REJECTED or DOUBLE_SPEND_ATTEMPTED (bcommon words it "arcade refused" or "the network refused");
• arcade's HTTP 422, or 460 to 475, its documented validation refusals (malformed, inputs, fee, a conflicting transaction);
• a node's RPC error -25 (RPC_VERIFY_ERROR) or -26 (RPC_VERIFY_REJECTED), except a full mempool or a chain too long, which pass.

Everything else is transient: a leg that cannot be reached, a 5xx, a 429, no verdict yet.

Example

A settlement leg's error is either the network's definitive refusal of these bytes, which no retry changes, or something transient.

package main

import (
	"errors"
	"fmt"

	"github.com/lightwebinc/bcommon/chainview"
)

func main() {
	for _, e := range []string{
		"publish: arcade refused 5f2c: REJECTED: bad-txns-inputs-missingorspent",
		"publish: sendrawtransaction: rpc error -26: mandatory-script-verify-flag-failed",
		"publish: sendrawtransaction: rpc error -26: mempool full",
		"publish: arcade answered 503: busy",
		"context deadline exceeded",
	} {
		_, refused := chainview.RefusedAnswer(errors.New(e))
		fmt.Printf("%t  %s\n", refused, e)
	}
}

Output:
true  publish: arcade refused 5f2c: REJECTED: bad-txns-inputs-missingorspent
true  publish: sendrawtransaction: rpc error -26: mandatory-script-verify-flag-failed
false  publish: sendrawtransaction: rpc error -26: mempool full
false  publish: arcade answered 503: busy
false  context deadline exceeded

func SpentElsewhere

func SpentElsewhere(ctx context.Context, a *nodeapi.Asset, tx *transaction.Transaction) string

SpentElsewhere names the first input of tx that the node shows spent by another transaction, in words, or "" when none is: then tx can still mine as far as its inputs go. An input the node cannot answer for is passed over. The node's view is bcommon's (nodeapi.Asset.SpentElsewhere); this only words it.