How to use miner.start(2) from javascript

Question

Refering to "Common useful JavaScript snippets for geth"

Got Following example to run miner from javascript:

1. Mine only when there are transactions!

var mining_threads = 1

function checkWork() {
    if (eth.getBlock("pending").transactions.length > 0) {
        if (eth.mining) return;
        console.log("== Pending transactions! Mining...");
        miner.start(mining_threads);
    } else {
        miner.stop(0);  // This param means nothing
        console.log("== No transactions! Mining stopped.");
    }
}

eth.filter("latest", function(err, block) { checkWork(); });
eth.filter("pending", function(err, block) { checkWork(); });

checkWork();

I am not able to use miner.start(mining_threads). Currently, I am using the following libraries:

• jquery-1.12.0.min.js
• bignumber.min.js
• web3-light.js
• web3Init.js

It would be really great if someone could help me out here.

Answer 1

miner.start will tell geth to start mining.

For that to work, you need to load the mining module into geth when you start geth. The mining module is not loaded by default. I'm assuming that is the problem since you didn't post any error info.

See the official wiki documentation.