refactor(clients): improve readability

* add some error cases

Signed-off-by: Julian Strobl <jmastr@mailbox.org>

clients/claim/client.go

@@ -2,6 +2,8 @@ package claim
 
 import (
 	"context"
+	"errors"
+	"fmt"
 	"net/http"
 
 	"github.com/planetmint/planetmint-go/config"
@@ -9,22 +11,38 @@ import (
 	"github.com/rddl-network/rddl-claim-service/types"
 )
 
-var ClaimServiceClient client.IRCClient
+var (
+	RCClient client.IRCClient
+)
 
 func lazyLoad() client.IRCClient {
-	if ClaimServiceClient != nil {
+	if RCClient != nil {
-		return ClaimServiceClient
+		return RCClient
 	}
 	cfg := config.GetConfig()
-	ClaimServiceClient = client.NewRCClient(cfg.ClaimHost, &http.Client{})
+	RCClient = client.NewRCClient(cfg.ClaimHost, &http.Client{})
-	return ClaimServiceClient
+	return RCClient
 }
 
 func PostClaim(ctx context.Context, beneficiary string, amount uint64, id uint64) (txID string, err error) {
+	if beneficiary == "" {
+		return txID, errors.New("beneficiary cannot be empty")
+	}
+
+	if amount == 0 {
+		return txID, errors.New("amount must be greater than 0")
+	}
+
+	req := types.PostClaimRequest{
+		Beneficiary: beneficiary,
+		Amount:      amount,
+		ClaimID:     int(id),
+	}
+
 	client := lazyLoad()
-	res, err := client.PostClaim(ctx, types.PostClaimRequest{Beneficiary: beneficiary, Amount: amount, ClaimID: int(id)})
+	resp, err := client.PostClaim(ctx, req)
 	if err != nil {
-		return
+		return txID, fmt.Errorf("failed to post claim: %w", err)
 	}
-	return res.TxID, nil
+	return resp.TxID, nil
 }

clients/shamir/coordinator/client.go

@@ -2,14 +2,16 @@ package coordinator
 
 import (
 	"context"
-	"log"
+	"errors"
 
 	"github.com/planetmint/planetmint-go/config"
 	"github.com/rddl-network/go-utils/tls"
 	"github.com/rddl-network/shamir-coordinator-service/client"
 )
 
-var ShamirCoordinatorServiceClient client.IShamirCoordinatorClient
+var (
+	ShamirCoordinatorServiceClient client.IShamirCoordinatorClient
+)
 
 func lazyLoad() client.IShamirCoordinatorClient {
 	if ShamirCoordinatorServiceClient != nil {
@@ -18,7 +20,8 @@ func lazyLoad() client.IShamirCoordinatorClient {
 	cfg := config.GetConfig()
 	httpsClient, err := tls.Get2WayTLSClient(cfg.CertsPath)
 	if err != nil {
-		defer log.Fatal("fatal error setting up mutual tls client for shamir coordinator")
+		err := errors.New("fatal error setting up mutual tls client for shamir coordinator")
+		panic(err)
 	}
 	ShamirCoordinatorServiceClient = client.NewShamirCoordinatorClient(cfg.IssuerHost, httpsClient)
 	return ShamirCoordinatorServiceClient
@@ -26,27 +29,27 @@ func lazyLoad() client.IShamirCoordinatorClient {
 
 func SendTokens(ctx context.Context, recipient string, amount string, asset string) (txID string, err error) {
 	client := lazyLoad()
-	res, err := client.SendTokens(ctx, recipient, amount, asset)
+	resp, err := client.SendTokens(ctx, recipient, amount, asset)
 	if err != nil {
 		return
 	}
-	return res.TxID, nil
+	return resp.TxID, nil
 }
 
 func ReIssueAsset(ctx context.Context, asset string, amount string) (txID string, err error) {
 	client := lazyLoad()
-	res, err := client.ReIssueAsset(ctx, asset, amount)
+	resp, err := client.ReIssueAsset(ctx, asset, amount)
 	if err != nil {
 		return
 	}
-	return res.TxID, nil
+	return resp.TxID, nil
 }
 
 func IssueNFTAsset(ctx context.Context, name string, machineAddress string, domain string) (assetID string, contract string, hexTx string, err error) {
 	client := lazyLoad()
-	res, err := client.IssueMachineNFT(ctx, name, machineAddress, domain)
+	resp, err := client.IssueMachineNFT(ctx, name, machineAddress, domain)
 	if err != nil {
 		return
 	}
-	return res.Asset, res.Contract, res.HexTX, nil
+	return resp.Asset, resp.Contract, resp.HexTX, nil
 }

testutil/network/loader.go

@@ -56,7 +56,7 @@ func Load(t *testing.T, configs ...Config) *Network {
 	claimMock.EXPECT().PostClaim(gomock.Any(), gomock.Any()).AnyTimes().Return(rcctypes.PostClaimResponse{
 		TxID: "0000000000000000000000000000000000000000000000000000000000000000",
 	}, nil)
-	claim.ClaimServiceClient = claimMock
+	claim.RCClient = claimMock
 
 	shamirMock := clientmocks.NewMockIShamirCoordinatorClient(ctrl)
 	shamirMock.EXPECT().SendTokens(gomock.Any(), gomock.Any(), gomock.Any(), gomock.Any()).AnyTimes().Return(scctypes.SendTokensResponse{