[Tokenomics] Implement difficulty proportional rewards (#880)

**This is a repost of PR #840 which did not get merged into main**

## Summary

This PR incorporated the mining difficulty into the claim reward
calculation.
* Encapsulates the claimed tokens into a `claim.GetClaimeduPOKT(params,
difficulty)`
* Implements a test to assert that the difficulty based rewards are
proportional to the off-chain relays served.
* Removes unused `min_relay_difficulty_bits` gov. param.

It is based on the preparation work of PR #836.

## Issue

- #781 
- #758 

## Type of change

Select one or more from the following:

- [x] New feature, functionality or library
- [ ] Consensus breaking; add the `consensus-breaking` label if so. See
#791 for details
- [ ] Bug fix
- [ ] Code health or cleanup
- [ ] Documentation
- [ ] Other (specify)

## Testing

- [x] **Unit Tests**: `make go_develop_and_test`
- [x] **LocalNet E2E Tests**: `make test_e2e`
- [ ] **DevNet E2E Tests**: Add the `devnet-test-e2e` label to the PR.

## Sanity Checklist

- [x] I have tested my changes using the available tooling
- [x] I have commented my code
- [x] I have performed a self-review of my own code; both comments &
source code
- [ ] I create and reference any new tickets, if applicable
- [x] I have left TODOs throughout the codebase, if applicable

docusaurus/docs/develop/developer_guide/adding_params.md

@@ -148,9 +148,19 @@ with the default value for the new parameter.
         "@type": "/poktroll.proof.MsgUpdateParams",
         "authority": "pokt10d07y265gmmuvt4z0w9aw880jnsr700j8yv32t",
         "params": {
-          "min_relay_difficulty_bits": "0",
           "proof_request_probability": "0.25",
-          "proof_requirement_threshold": "20",
+          "proof_requirement_threshold":  {
+            "denom": "upokt",
+            "amount": "20000000"
+          },
+          "proof_missing_penalty": {
+            "amount": "320000000",
+            "denom": "upokt"
+          },
+          "proof_submission_fee": {
+            "amount": "1000000",
+            "denom": "upokt"
+          },
           "new_parameter_name": "100" // Add this line
         }
       }

makefiles/params.mk

@@ -40,10 +40,6 @@ params_get_proof: ## Get the proof module params
 params_update_proof_all: ## Update the proof module params
 	poktrolld tx authz exec ./tools/scripts/params/proof_all.json $(PARAM_FLAGS)
 
-.PHONY: params_update_proof_min_relay_difficulty_bits
-params_update_proof_min_relay_difficulty_bits: ## Update the proof module min_relay_difficulty_bits param
-	poktrolld tx authz exec ./tools/scripts/params/proof_min_relay_difficulty_bits.json $(PARAM_FLAGS)
-
 .PHONY: params_update_proof_proof_request_probability
 params_update_proof_proof_request_probability: ## Update the proof module proof_request_probability param
 	poktrolld tx authz exec ./tools/scripts/params/proof_proof_request_probability.json $(PARAM_FLAGS)

pkg/client/interface.go

@@ -356,7 +356,7 @@ type ProofQueryClient interface {
 type ServiceQueryClient interface {
 	// GetService queries the chain for the details of the service provided
 	GetService(ctx context.Context, serviceId string) (sharedtypes.Service, error)
-	GetServiceRelayDifficultyTargetHash(ctx context.Context, serviceId string) (servicetypes.RelayMiningDifficulty, error)
+	GetServiceRelayDifficulty(ctx context.Context, serviceId string) (servicetypes.RelayMiningDifficulty, error)
 }
 
 // BankQueryClient defines an interface that enables the querying of the

pkg/client/query/servicequerier.go

@@ -5,8 +5,11 @@ import (
 
 	"cosmossdk.io/depinject"
 	"github.com/cosmos/gogoproto/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 
 	"github.com/pokt-network/poktroll/pkg/client"
+	"github.com/pokt-network/poktroll/pkg/crypto/protocol"
 	servicetypes "github.com/pokt-network/poktroll/x/service/types"
 	sharedtypes "github.com/pokt-network/poktroll/x/shared/types"
 )
@@ -61,9 +64,9 @@ func (servq *serviceQuerier) GetService(
 	return res.Service, nil
 }
 
-// GetServiceRelayDifficultyTargetHash queries the onchain data for
+// GetServiceRelayDifficulty queries the onchain data for
 // the relay mining difficulty associated with the given service.
-func (servq *serviceQuerier) GetServiceRelayDifficultyTargetHash(
+func (servq *serviceQuerier) GetServiceRelayDifficulty(
 	ctx context.Context,
 	serviceId string,
 ) (servicetypes.RelayMiningDifficulty, error) {
@@ -72,8 +75,19 @@ func (servq *serviceQuerier) GetServiceRelayDifficultyTargetHash(
 	}
 
 	res, err := servq.serviceQuerier.RelayMiningDifficulty(ctx, req)
+	if status.Code(err) == codes.NotFound {
+		newServiceDifficulty := servicetypes.RelayMiningDifficulty{
+			ServiceId:    serviceId,
+			BlockHeight:  0,
+			NumRelaysEma: 0,
+			TargetHash:   protocol.BaseRelayDifficultyHashBz,
+		}
+
+		return newServiceDifficulty, nil
+	}
 	if err != nil {
 		return servicetypes.RelayMiningDifficulty{}, err
 	}
+
 	return res.RelayMiningDifficulty, nil
 }

pkg/relayer/miner/gen/gen_fixtures.go

@@ -40,7 +40,6 @@ const (
 	defaultSvcID = "svc1"
 )
 
-// TODO_FOLLOWUP(@olshansk, #690): Do a global anycase grep for "DifficultyBits" and update/remove things appropriately.
 var (
 	// flagDifficultyThresholdHashStr is the difficulty threshold hash, as a hex string, that a
 	// randomized, serialized relay must be greater than to be included in the

pkg/relayer/miner/miner.go

@@ -128,11 +128,9 @@ func (mnr *miner) getServiceRelayDifficultyTargetHash(ctx context.Context, req *
 		return nil, fmt.Errorf("invalid session header: %w", err)
 	}
 
-	serviceRelayDifficulty, err := mnr.serviceQueryClient.GetServiceRelayDifficultyTargetHash(ctx, sessionHeader.ServiceId)
+	serviceRelayDifficulty, err := mnr.serviceQueryClient.GetServiceRelayDifficulty(ctx, sessionHeader.ServiceId)
 	if err != nil {
-		// TODO_IMPROVE: log the error and a message saying the default relay difficulty target hash
-		// is being used.
-		return protocol.BaseRelayDifficultyHashBz, nil
+		return nil, err
 	}
 
 	return serviceRelayDifficulty.GetTargetHash(), nil

pkg/relayer/miner/miner_test.go

@@ -46,12 +46,10 @@ func TestMiner_MinedRelays(t *testing.T) {
 		expectedMinedRelays                   = unmarshalHexMinedRelays(t, marshaledMinableRelaysHex)
 	)
 
-	proofQueryClientMock := testqueryclients.NewTestProofQueryClient(t)
-
 	testqueryclients.SetServiceRelayDifficultyTargetHash(t, testSvcId, testRelayMiningTargetHash)
 	serviceQueryClientMock := testqueryclients.NewTestServiceQueryClient(t)
 
-	deps := depinject.Supply(proofQueryClientMock, serviceQueryClientMock)
+	deps := depinject.Supply(serviceQueryClientMock)
 	mnr, err := miner.NewMiner(deps)
 	require.NoError(t, err)
 

pkg/relayer/session/claim.go

@@ -315,10 +315,12 @@ func (rs *relayerSessionsManager) payableProofsSessionTrees(
 		).Warn().Msg("supplier operator cannot afford to submit proof for claim, skipping")
 	}
 
-	logger.Warn().Msgf(
-		"Supplier operator %q can only afford %d out of %d claims",
-		supplierOpeartorAddress, len(claimableSessionTrees), len(sessionTrees),
-	)
+	if len(claimableSessionTrees) < len(sessionTrees) {
+		logger.Warn().Msgf(
+			"Supplier operator %q can only afford %d out of %d claims",
+			supplierOpeartorAddress, len(claimableSessionTrees), len(sessionTrees),
+		)
+	}
 
 	return claimableSessionTrees, nil
 }

pkg/relayer/session/proof.go

@@ -15,7 +15,6 @@ import (
 	"github.com/pokt-network/poktroll/x/proof/types"
 	prooftypes "github.com/pokt-network/poktroll/x/proof/types"
 	"github.com/pokt-network/poktroll/x/shared"
-	tokenomics "github.com/pokt-network/poktroll/x/tokenomics"
 )
 
 // submitProofs maps over the given claimedSessions observable.
@@ -277,24 +276,25 @@ func (rs *relayerSessionsManager) isProofRequired(
 	// Create the claim object and use its methods to determine if a proof is required.
 	claim := claimFromSessionTree(sessionTree)
 
-	// Get the number of compute units accumulated through the given session.
-	numClaimComputeUnits, err := claim.GetNumClaimedComputeUnits()
+	proofParams, err := rs.proofQueryClient.GetParams(ctx)
 	if err != nil {
 		return false, err
 	}
 
-	proofParams, err := rs.proofQueryClient.GetParams(ctx)
+	sharedParams, err := rs.sharedQueryClient.GetParams(ctx)
 	if err != nil {
 		return false, err
 	}
 
-	sharedParams, err := rs.sharedQueryClient.GetParams(ctx)
+	// Retrieving the relay mining difficulty for the service at hand
+	serviceId := claim.GetSessionHeader().GetServiceId()
+	relayMiningDifficulty, err := rs.serviceQueryClient.GetServiceRelayDifficulty(ctx, serviceId)
 	if err != nil {
 		return false, err
 	}
 
 	// The amount of uPOKT being claimed.
-	claimedAmount, err := tokenomics.NumComputeUnitsToCoin(*sharedParams, numClaimComputeUnits)
+	claimedAmount, err := claim.GetClaimeduPOKT(*sharedParams, relayMiningDifficulty)
 	if err != nil {
 		return false, err
 	}

pkg/relayer/session/session_test.go

@@ -60,6 +60,8 @@ func requireProofCountEqualsExpectedValueFromProofParams(t *testing.T, proofPara
 		Id:                   "svc",
 		ComputeUnitsPerRelay: 2,
 	}
+
+	testqueryclients.SetServiceRelayDifficultyTargetHash(t, service.Id, protocol.BaseRelayDifficultyHashBz)
 	// Add the service to the existing services.
 	testqueryclients.AddToExistingServices(t, service)
 
@@ -157,12 +159,14 @@ func TestRelayerSessionsManager_InsufficientBalanceForProofSubmission(t *testing
 		ComputeUnitsPerRelay: 1,
 	}
 	testqueryclients.AddToExistingServices(t, lowCUPRService)
+	testqueryclients.SetServiceRelayDifficultyTargetHash(t, lowCUPRService.Id, protocol.BaseRelayDifficultyHashBz)
 
 	highCUPRService := sharedtypes.Service{
 		Id:                   "highCUPRService",
 		ComputeUnitsPerRelay: 2,
 	}
 	testqueryclients.AddToExistingServices(t, highCUPRService)
+	testqueryclients.SetServiceRelayDifficultyTargetHash(t, highCUPRService.Id, protocol.BaseRelayDifficultyHashBz)
 
 	lowCUPRServiceActiveSession := &sessiontypes.Session{
 		Header: &sessiontypes.SessionHeader{

proto/poktroll/proof/event.proto

@@ -13,7 +13,7 @@ message EventClaimCreated {
   uint64 num_relays = 2 [(gogoproto.jsontag) = "num_relays"];
   uint64 num_claimed_compute_units = 4 [(gogoproto.jsontag) = "num_claimed_compute_units"];
   uint64 num_estimated_compute_units = 5 [(gogoproto.jsontag) = "num_estimated_compute_units"];
-  cosmos.base.v1beta1.Coin claimed_amount_upokt = 6 [(gogoproto.jsontag) = "claimed_amount_upokt"];
+  cosmos.base.v1beta1.Coin claimed_upokt = 6 [(gogoproto.jsontag) = "claimed_upokt"];
 }
 
 // TODO_TEST: Add coverage for claim updates.
@@ -22,7 +22,7 @@ message EventClaimUpdated {
   uint64 num_relays = 2 [(gogoproto.jsontag) = "num_relays"];
   uint64 num_claimed_compute_units = 4 [(gogoproto.jsontag) = "num_claimed_compute_units"];
   uint64 num_estimated_compute_units = 5 [(gogoproto.jsontag) = "num_estimated_compute_units"];
-  cosmos.base.v1beta1.Coin claimed_amount_upokt = 6 [(gogoproto.jsontag) = "claimed_amount_upokt"];
+  cosmos.base.v1beta1.Coin claimed_upokt = 6 [(gogoproto.jsontag) = "claimed_upokt"];
 }
 
 message EventProofSubmitted {
@@ -31,7 +31,7 @@ message EventProofSubmitted {
   uint64 num_relays = 3 [(gogoproto.jsontag) = "num_relays"];
   uint64 num_claimed_compute_units = 4 [(gogoproto.jsontag) = "num_claimed_compute_units"];
   uint64 num_estimated_compute_units = 5 [(gogoproto.jsontag) = "num_estimated_compute_units"];
-  cosmos.base.v1beta1.Coin claimed_amount_upokt = 6 [(gogoproto.jsontag) = "claimed_amount_upokt"];
+  cosmos.base.v1beta1.Coin claimed_upokt = 6 [(gogoproto.jsontag) = "claimed_upokt"];
 }
 
 // TODO_TEST: Add coverage for proof updates.
@@ -41,5 +41,5 @@ message EventProofUpdated {
   uint64 num_relays = 3 [(gogoproto.jsontag) = "num_relays"];
   uint64 num_claimed_compute_units = 4 [(gogoproto.jsontag) = "num_claimed_compute_units"];
   uint64 num_estimated_compute_units = 5 [(gogoproto.jsontag) = "num_estimated_compute_units"];
-  cosmos.base.v1beta1.Coin claimed_amount_upokt = 6 [(gogoproto.jsontag) = "claimed_amount_upokt"];
+  cosmos.base.v1beta1.Coin claimed_upokt = 6 [(gogoproto.jsontag) = "claimed_upokt"];
 }

proto/poktroll/service/relay_mining_difficulty.proto

@@ -8,6 +8,7 @@ import "gogoproto/gogo.proto";
 
 // RelayMiningDifficulty is a message used to store the on-chain Relay Mining
 // difficulty associated with a specific service ID.
+// TODO_TECHDEBT: Embed this message in the Service message.
 message RelayMiningDifficulty {
     // The service ID the relay mining difficulty is associated with.
     string service_id = 1;

proto/poktroll/tokenomics/event.proto

@@ -29,9 +29,9 @@ message EventClaimExpired {
     // Number of estimated compute units claimed as a function of the number of claimed
     // compute units and the relay difficulty multiplier for the particular service.
     uint64 num_estimated_compute_units = 5 [(gogoproto.jsontag) = "num_estimated_compute_units"];
-    // The amount of uPOKT claimed to be rewarded for the work done as a function of
+    // The uPOKT coin claimed to be rewarded for the work done as a function of
     // the number of estimated compute units and the compute uints to token multiplier.
-    cosmos.base.v1beta1.Coin claimed_amount_upokt = 6 [(gogoproto.jsontag) = "claimed_amount_upokt"];
+    cosmos.base.v1beta1.Coin claimed_upokt = 6 [(gogoproto.jsontag) = "claimed_upokt"];
 }
 
 // EventClaimSettled is an event emitted whenever a claim is settled.
@@ -48,9 +48,9 @@ message EventClaimSettled {
     // Number of estimated compute units claimed as a function of the number of claimed
     // compute units and the relay difficulty multiplier for the particular service.
     uint64 num_estimated_compute_units = 5 [(gogoproto.jsontag) = "num_estimated_compute_units"];
-    // The amount of uPOKT claimed to be rewarded for the work done as a function of
+    // The uPOKT coin claimed to be rewarded for the work done as a function of
     // the number of estimated compute units and the compute uints to token multiplier.
-    cosmos.base.v1beta1.Coin claimed_amount_upokt = 6 [(gogoproto.jsontag) = "claimed_amount_upokt"];
+    cosmos.base.v1beta1.Coin claimed_upokt = 6 [(gogoproto.jsontag) = "claimed_upokt"];
 }
 
 // EventApplicationOverserviced is emitted when an application has less stake than

tests/integration/service/relay_mining_difficulty_test.go

@@ -2,12 +2,15 @@ package integration_test
 
 import (
 	"context"
+	"math"
 	"testing"
 
+	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/pokt-network/smt"
 	"github.com/pokt-network/smt/kvstore/pebble"
 	"github.com/stretchr/testify/require"
 
+	"github.com/pokt-network/poktroll/app/volatile"
 	"github.com/pokt-network/poktroll/cmd/poktrolld/cmd"
 	"github.com/pokt-network/poktroll/pkg/crypto/protocol"
 	testutilevents "github.com/pokt-network/poktroll/testutil/events"
@@ -38,6 +41,20 @@ func TestUpdateRelayMiningDifficulty_NewServiceSeenForTheFirstTime(t *testing.T)
 	// Get the current session and shared params
 	session := getSession(t, integrationApp)
 	sharedParams := getSharedParams(t, integrationApp)
+	proofParams := getProofParams(t, integrationApp)
+
+	// Update the proof parameters to never require a proof, since this test is not
+	// submitting any proofs.
+	maxProofRequirementThreshold := sdk.NewInt64Coin(volatile.DenomuPOKT, math.MaxInt64)
+	proofParams.ProofRequirementThreshold = &maxProofRequirementThreshold
+	proofParams.ProofRequestProbability = 0
+
+	msgProofParams := prooftypes.MsgUpdateParams{
+		Authority: integrationApp.GetAuthority(),
+		Params:    proofParams,
+	}
+	_, err := integrationApp.RunMsg(t, &msgProofParams)
+	require.NoError(t, err)
 
 	// Prepare the trie with several mined relays
 	expectedNumRelays := uint64(100)
@@ -138,6 +155,21 @@ func getSharedParams(t *testing.T, integrationApp *testutil.App) sharedtypes.Par
 	return sharedQueryRes.Params
 }
 
+// getProofParams returns the proof parameters for the current block height.
+func getProofParams(t *testing.T, integrationApp *testutil.App) prooftypes.Params {
+	t.Helper()
+
+	sdkCtx := integrationApp.GetSdkCtx()
+
+	proofQueryClient := prooftypes.NewQueryClient(integrationApp.QueryHelper())
+	proofParamsReq := prooftypes.QueryParamsRequest{}
+
+	proofQueryRes, err := proofQueryClient.Params(sdkCtx, &proofParamsReq)
+	require.NoError(t, err)
+
+	return proofQueryRes.Params
+}
+
 // getSession returns the current session for the default application and service.
 func getSession(t *testing.T, integrationApp *testutil.App) *sessiontypes.Session {
 	t.Helper()