Fix ya-provider incorrectly computing Invoice/DebitNotes costs

agent/provider/src/payments/pricing.rs

@@ -1,6 +1,7 @@
 use anyhow::{anyhow, Result};
-use bigdecimal::{BigDecimal, FromPrimitive};
+use bigdecimal::BigDecimal;
 use serde_json::json;
+use std::convert::TryFrom;
 
 use ya_agreement_utils::ComInfo;
 use ya_client::model::{payment::Account, NodeId};
@@ -38,23 +39,27 @@ pub trait PricingOffer {
 
 /// Computes computations costs.
 pub struct LinearPricing {
-    usage_coeffs: Vec<f64>,
+    usage_coeffs: Vec<BigDecimal>,
 }
 
 impl PaymentModel for LinearPricing {
     fn compute_cost(&self, usage: &[f64]) -> Result<BigDecimal> {
+        let usage: Vec<BigDecimal> = usage
+            .iter()
+            .cloned()
+            .map(BigDecimal::try_from)
+            .collect::<std::result::Result<_, _>>()
+            .map_err(|e| anyhow!("Failed to convert usage to BigDecimal: {e}"))?;
+
         // Note: last element of usage_coeffs contains constant initial cost
         // of computing task, so we don't multiply it.
         let const_coeff_idx = self.usage_coeffs.len() - 1;
-        let cost: f64 = self.usage_coeffs[const_coeff_idx]
+        Ok(self.usage_coeffs[const_coeff_idx].clone()
             + self.usage_coeffs[0..const_coeff_idx]
                 .iter()
                 .zip(usage.iter())
                 .map(|(coeff, usage_value)| coeff * usage_value)
-                .sum::<f64>();
-
-        BigDecimal::from_f64(cost)
-            .ok_or_else(|| anyhow!("Failed to convert to BigDecimal: {}", cost))
+                .sum::<BigDecimal>())
     }
 
     fn expected_usage_len(&self) -> usize {
@@ -64,12 +69,15 @@ impl PaymentModel for LinearPricing {
 
 impl LinearPricing {
     pub fn new<'a>(commercials: &'a PaymentDescription<'a>) -> Result<LinearPricing> {
-        let usage: Vec<f64> = commercials.get_usage_coefficients()?;
+        let usage: Vec<BigDecimal> = commercials
+            .get_usage_coefficients()?
+            .into_iter()
+            .map(BigDecimal::try_from)
+            .collect::<std::result::Result<_, _>>()
+            .map_err(|e| anyhow!("Failed to convert usage coefficients to BigDecimal: {e}"))?;
+
+        log::info!("Creating LinearPricing payment model. Usage coefficients vector: {usage:?}.");
 
-        log::info!(
-            "Creating LinearPricing payment model. Usage coefficients vector: {:?}.",
-            usage
-        );
         Ok(LinearPricing {
             usage_coeffs: usage,
         })
@@ -142,3 +150,89 @@ impl PricingOffer for LinearPricingOffer {
         Ok(ComInfo { params })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use bigdecimal::BigDecimal;
+    use std::convert::TryFrom;
+    use std::str::FromStr;
+    use test_case::test_case;
+
+    use crate::payments::model::{PaymentDescription, PaymentModel};
+    use crate::payments::LinearPricing;
+
+    use ya_agreement_utils::agreement::try_from_json;
+    use ya_agreement_utils::AgreementView;
+    use ya_framework_basic::template::template;
+
+    const AGREEMENT_TEMPLATE: &str = r#"
+{
+  "agreementId": "0ec929f5acc8f98a47ab72d61a2c2f343d45d8438d3aa4ccdc84e717c219e185",
+  "proposedSignature": "NoSignature",
+  "state": "Pending",
+  "timestamp": "2022-05-22T10:41:42.564784259Z",
+  "validTo": "2022-05-22T11:41:42.562457Z",
+
+  "offer": {
+    "properties": {
+      "golem.com.payment.debit-notes.accept-timeout?": 240,
+      "golem.com.payment.platform.erc20-goerli-tglm.address": "0x95369fc6fd02afeca110b9c32a21fb8ad899ee0a",
+      "golem.com.pricing.model": "linear",
+      "golem.com.pricing.model.linear.coeffs": [${coeffs}],
+      "golem.com.scheme": "payu",
+      "golem.com.scheme.payu.debit-note.interval-sec?": 120,
+      "golem.com.scheme.payu.payment-timeout-sec?": 120,
+      "golem.com.usage.vector": [
+        "golem.usage.cpu_sec",
+        "golem.usage.duration_sec"
+      ]
+    },
+    "constraints": "(&\n  (golem.srv.comp.expiration>1705586871777)\n)",
+    "offerId": "afce49b1ea5b45db91bdd6e5481479f9-9095fca9dea0a91ce95cf994125b33cdd838fcc963a1106f2be9e4b5b65a52f0",
+    "providerId": "0x86a269498fb5270f20bdc6fdcf6039122b0d3b23",
+    "timestamp": "2022-05-22T10:41:42.564784259Z"
+  },
+
+  "demand": {
+    "constraints": "(&(golem.com.payment.platform.erc20-goerli-tglm.address=*)\n\t(golem.com.pricing.model=linear)\n\t(&(golem.inf.mem.gib>=0.5)\n\t(golem.inf.storage.gib>=2.0)\n\t(golem.inf.cpu.threads>=1)\n\t(golem.runtime.name=ya-mock-runtime)))",
+    "demandId": "773035fc685c46da8e61473ac2a2568e-3f3eb86d6ef9a01708d0f57d0b19cc69fd74422150c120e33cc1b5f4a1a12b96",
+    "properties": {},
+    "requestorId": "0xa5ad3f81e283983b8e9705b2e31d0c138bb2b1b7",
+    "timestamp": "2022-05-22T10:41:42.564784259Z"
+  }
+}
+"#;
+
+    #[test_case(
+        "0.0001, 0.00005, 0.0",
+        &[44.017951, 103.002864998],
+        BigDecimal::from_str("0.0095519383499").unwrap();
+        "Check non-represented float values"
+    )]
+    #[test_case(
+        "0.002, 0.008, 0.0",
+        &[44.094619588, 0.0],
+        BigDecimal::from_str("0.088189239176").unwrap();
+        "Check overflowing example"
+    )]
+    #[test_case(
+        "0.002, 0.008, 0.0",
+        &[24.141030488, 0.0],
+        BigDecimal::from_str("0.048282060976").unwrap();
+        "Check underflowing example"
+    )]
+    fn test_linear_payment_model_cost(coeffs: &str, usage: &[f64], expected: BigDecimal) {
+        let agreement = AgreementView::try_from(
+            try_from_json(template(
+                AGREEMENT_TEMPLATE,
+                &[("coeffs", coeffs.to_string())],
+            ))
+            .unwrap(),
+        )
+        .unwrap();
+        let payment = PaymentDescription::new(&agreement).unwrap();
+        let pricing = LinearPricing::new(&payment).unwrap();
+
+        assert_eq!(pricing.compute_cost(usage).unwrap(), expected);
+    }
+}

test-utils/test-framework/framework-basic/src/lib.rs

@@ -4,3 +4,4 @@ pub mod hash;
 pub mod log;
 pub mod server_external;
 pub mod temp;
+pub mod template;

test-utils/test-framework/framework-basic/src/template.rs

@@ -0,0 +1,7 @@
+pub fn template(template: &str, vars: &[(&str, String)]) -> String {
+    let mut template = template.to_string();
+    for var in vars {
+        template = template.replace(&format!("${{{}}}", var.0), &var.1);
+    }
+    template
+}