Price configuration

dRPC provides pay as you go pricing for our clients, meaning the pay for each call. Each call has a price in terms of CU (compute units), you can read more here.

But providers can redefine those values for themselves through provider dashboard using CU lang.

CU lang#

We provide a small configuration language that allows to set prices. If you're familiar with CSS, it's very similar and allows you to easily augment prices for borad range of methods.

Example

// multiplies all prices by 0.9
* {
  mul: 0.9;
}

// all methods for solana will use 100% of CU
$solana {
  mul: 1;
}

// drops price by 50% on all network for eth_call method
#eth_call {
  mul: 0.5;
}

// only drop price by 20% for eth_call on metis
$metis #eth_call {
  mul: 0.8;
}

// all archive eth_call on ethereum will have 100% price
$ethereum #eth_call archive {
  mul: 1;
}

// both networks will use 100% of CU
$metis, $manta-pacific {
  mul: 1;
}

// adds discount for all requests in US-East
region(US-East) {
  mul: 0.9;
}

Anatomy of pricing rule

Each rule consists of 2 parts: selector and modifier.

• selector allows to specify for which call modifier should apply
• modifier augments the prices for selected calls

Modifiers

Currently we only support mul modifier. This modifier takes base price of the call and multiplies it by specified number. Currently we only allow float values between 0 and 1, so base price is currently price ceiling, but it can change in future.

Selectors

There are several types of selectors

• all (*) selector, applies to all calls
• method selector (#eth_call), applies to all calls of specifci methods
• network selector ($solana), applies to all calls of specific networks
• archive selector (archive), applies to all archive calls
• region selector (region(US-East)), applies to all methods in specified region. Current regions are:
  • US-East
  • US-Central
  • Asia-East
  • Asia-SouthEast
  • EU-West
  • SA-East

Selectors composability

• * is not composable, you can only use it alone
• you can increase specificity of selector using several different types of selectors together $ethereum #eth_call archive, but you can only use 1 type of each selector
• you can combine several selectors in one using ,. For example, #eth_call, #eth_getLogs.

Specificity

Obviously, you can have a lot of rules in your configuration and each call can match several rules. However, we need to select one to apply its modifier, so there is a concept of specificity.

It works the same as with CSS. Basically we take selector and convert it to binary number using order below:

1. method selector
2. network selector
3. region selector
4. archive selector
5. all selector

For example, let's compare 2 selectors: #eth_call and $metis archive.

Selector #eth_call converts to 10000:

1. method selector (1)
2. network selector (0)
3. region selector (0)
4. archive selector (0)
5. all selector (0)

Selector $metis archive converts to 01010:

1. method selector (0)
2. network selector(1)
3. region selector (0)
4. archive selector (1)
5. all selector (0)

Now we just compare those 2 numbers and 10000 > 01010, so the selector #eth_call will have more specificity, thus it will overpower any other selector matching any eth_call.