What are the differences between callback and OAR address

Question

I am using Oraclize with testrpc and truffle and I have confused in some points

Now when I choose an address account when run the bridge, why and what is the purpose of the choice.

node bridge -a 1

here the account 1 from testrpc accounts has been chosen but I don't exactly how it will be used.

If the result will be sent back to the address who ask this data ( let's say I send query from account 2), the address suppose be my address( account 2) when I send the query, please correct my understanding if I understand wrongly.

Another point, does the sender address of the query result will be OAR ?? I mean the sender of the query result will be the OAR ??

Thanks

Answer 1

Nicola from Oraclize here.

The --account (-a) option lets you choose your callback address (cbAddress) only, this is important because the account must be unlocked and have enough funds.

This is mainly used to deploy/update all Oraclize contracts (Oraclize Address Resolver (OAR) and the Oraclize Connector) and to send back the responses of your contract queries (the transactions calling your __callback method).

The OAR address can vary and is used only to easily resolve the Oraclize connector address on your chain, it is something oraclizeAPI uses internally and you don't really have to manually manage any of all this.

Please note that the ethereum bridge tool is still experimental and will be discontinued soon in favour of a new tool called "stargate" which will be much easier to install and maintain.