Gasmon

Gasmon monitors the current Gas prices on the Ethereum blockchain. It allows you to select a speed for your transactions based on the data provided by Eth Gas Station (https://ethgasstation.info/), instead of setting gasPrice manually.

It periodically consumes Eth Gas Station's API to get the four basic speeds ("safeLow", "average", "fast" and "fastest"), their corresponding Gas prices and estimated waiting times.

Gasmon provides you with the optimal Gas price for the desired speed, at any given moment.

Usage

1. Install it with npm install gasmon
2. Import it in your project with import Gasmon from 'gasmon';
3. Initialize it with Gasmon.init();
4. Define the default speed with Gasmon.setSpeed(speed), where speed is an integer from 1 to 4, representing the speeds "SafeLow", "Average", "Fast" and "Fastest".
5. Get the ideal Gas price for the default speed with Gasmon.idealGasPrice()

Example: Gasmon.setSpeed(3), then Gasmon.idealGasPrice() will return the gasPrice necessary to make a "fast" transaction at the moment.

As an alternative, you can ask directly for the speed you want by calling Gasmon.idealGasPrice(3)

Example inside a transaction call:

contract.mint(to, tokens, {from:_user, gasPrice:Gasmon.idealGasPrice(3)})
    .then(function(receipt){
        onResult(receipt);
    });

Motivation

Sometimes you want to pay as low as you can for a tx, but you're afraid it might get stuck. Sometimes you want to pay as high as it takes, but not more than you need, to make your tx blazing fast.
Gasmon solves this problem by seamlessly delivering Eth Gas Station's gasPrice estimates to your system.
The lowest value, corresponding to speed 1 ("safeLow"), is never less than what's being accepted by miners in the network. According to Eth Gas Station, "this price is determined by the lowest price where at least 5% of the network hash power will accept it."
The highest value, corresponding to speed 4 ("fastest"), is never more than what you need. According to Eth Gas Station, "paying more than this price is unlikely to increase transaction confirmation time under normal circumstances."

No more worries, no more overspending.

More details:

• Initialize it with Gasmon.init(callbackFunction,checkIntervalInMinutes,suppressLogs)

• All parameters are optional.

• If you pass a callbackFunction, it will be called whenever the costs change in the network (and once as soon as it initializes).

• If you omit checkIntervalInMinutes, it defaults to 3. This is how long Gasmon takes to update gasPrices.

• If you omit suppressLogs, it defaults to false and you will see a console.log whenever speeds change.

• Access the ideal Gas price with Gasmon.idealGasPrice(speed), where speed is an integer from 1 to 4, representing the four available speeds.

• You can also use Gasmon.idealGasPriceInGwei(speed) to get the value in GWEI.

• If you omit the value speed when calling these functions, the system will use the default speed (2).

• Gasmon.setSpeed(speed) changes the default speed to speed (an integer from 1 to 4).

• Gasmon.nextSpeed() cycles the default speed between the available speeds.

• Gasmon.currentSpeed() consults what's the default speed. It returns an integer from 1 to 4.

• Gasmon.currentWait() returns the estimated waiting time in minutes for the default speed.

• Gasmon.speeds() returns an array with the GWEI costs for the four speeds and their respective waiting times in minutes. It will return an array like this: [{gwei:1,wait:5},{gwei:2,wait:2.9},{gwei:5,wait:1},{gwei:9,wait:0.5}]

• Gasmon.details() returns the last response gotten from Eth Gas Station's API, without any treatment. It will be something like this: {"fast": 80.0, "fastest": 350.0, "safeLow": 10.0, "average": 10.0, "block_time": 15.652173913043478, "blockNum": 9262855, "speed": 0.5371790597818887, "safeLowWait": 3.2, "avgWait": 3.2, "fastWait": 0.5, "fastestWait": 0.5, "gasPriceRange": {"350": 0.5, "330": 0.5, "310": 0.5, "290": 0.5, "270": 0.5, "250": 0.5, "230": 0.5, "210": 0.5, "190": 0.5, "180": 0.5, "170": 0.5, "160": 0.5, "150": 0.5, "140": 0.5, "130": 0.5, "120": 0.5, "110": 0.5, "100": 0.5, "90": 0.5, "80": 0.5, "70": 0.7, "60": 1.0, "50": 1.0, "40": 2.1, "30": 2.7, "20": 2.7, "10": 3.2, "8": 260.9, "6": 260.9, "4": 260.9}}

• Gasmon.optimized(false) deactivates optimization (active by default). When optimized, the system will check whether a given speed can be achieved by paying even less. That happens, for example, when the "fastest" price has the same waiting time as the "fast" price. In that case, Gasmon will automatically use the "fast" price for the "fastest" speed. Nevertheless, please consider this important comment from Eth Gas Station's team: "In essence, the model determines the gas price brackets by looking at the gas prices people recently spent and how they fared in the recently included blocks. Then it uses additional information to try and predict how those prices will do in the future. So, if in the past few blocks, those paying, say, 8 GWEI had close to the same results wrt block inclusion as the 'gas ballers' who paid 35GWEI, and things are not expected to change a lot over the next few blocks, you get this effect. It essentially means 'whether you pay 8GWEI, or 35GWEI like some did, you'll likely get included in the next 1 or 2 blocks'. There could still be a reason to pay the fastest price, e.g. if that tiny edge you expect to get from doing so, a maybe 5% additional chance of being included in the next block and not in the one after the next, is of economical relevance to you." If this is your case, then you should disable optimization.