Add GetLogsWithPagination

logs.go

@@ -7,15 +7,28 @@
 
 package etherscan
 
+type Option func(M)
+
+func WithPagination(page, offset int) Option {
+	return func(m M) {
+		m["page"] = page
+		m["offset"] = offset
+	}
+}
+
 // GetLogs gets logs that match "topic" emitted by the specified "address" between the "fromBlock" and "toBlock"
-func (c *Client) GetLogs(fromBlock, toBlock int, address, topic string) (logs []Log, err error) {
+func (c *Client) GetLogs(fromBlock, toBlock int, address, topic string, options ...Option) (logs []Log, err error) {
 	param := M{
 		"fromBlock": fromBlock,
 		"toBlock":   toBlock,
 		"topic0":    topic,
 		"address":   address,
 	}
 
+	for _, applyOpt := range options {
+		applyOpt(param)
+	}
+
 	err = c.call("logs", "getLogs", param, &logs)
 	return
 }

logs_e2e_test.go

@@ -1,6 +1,7 @@
 package etherscan
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
@@ -29,3 +30,125 @@ func TestClient_GetLogs(t *testing.T) {
 		t.Errorf("api.GetLogs not working\n: %s\n", cmp.Diff(expectedLogs, actualLogs))
 	}
 }
+
+func TestClient_GetLogsWithPagination(t *testing.T) {
+	expectedLogs := []Log{
+		{
+			Address: "0x33990122638b9132ca29c723bdf037f1a891a70c",
+			Topics: []string{"0xf63780e752c6a54a94fc52715dbc5518a3b4c3c2833d301a204226548a2a8545",
+				"0x72657075746174696f6e00000000000000000000000000000000000000000000",
+				"0x000000000000000000000000d9b2f59f3b5c7b3c67047d2f03c3e8052470be92"},
+			Data:            "0x",
+			BlockNumber:     "0x5c958",
+			BlockHash:       "0xe32a9cac27f823b18454e8d69437d2af41a1b81179c6af2601f1040a72ad444b",
+			TransactionHash: "0x0b03498648ae2da924f961dda00dc6bb0a8df15519262b7e012b7d67f4bb7e83",
+			LogIndex:        "0x",
+		},
+		{
+			Address: "0x33990122638b9132ca29c723bdf037f1a891a70c",
+			Topics: []string{"0xf63780e752c6a54a94fc52715dbc5518a3b4c3c2833d301a204226548a2a8545",
+				"0x6c6f747465727900000000000000000000000000000000000000000000000000",
+				"0x0000000000000000000000001f6cc3f7c927e1196c03ac49c5aff0d39c9d103d"},
+			Data:            "0x",
+			BlockNumber:     "0x5c965",
+			BlockHash:       "0x46e257ddbafca078402d0c49ad31c79514995667132c45eddbb8ca7153b6871e",
+			TransactionHash: "0x8c72ea19b48947c4339077bd9c9c09a780dfbdb1cafe68db4d29cdf2754adc11",
+			LogIndex:        "0x",
+		},
+		{
+			Address: "0x33990122638b9132ca29c723bdf037f1a891a70c",
+			Topics: []string{"0xf63780e752c6a54a94fc52715dbc5518a3b4c3c2833d301a204226548a2a8545",
+				"0x657870616e736500000000000000000000000000000000000000000000000000",
+				"0x000000000000000000000000d7586825a3177b1c6ef341ccb18361cfbc62dd0c"},
+			Data:            "0x",
+			BlockNumber:     "0x6664c",
+			BlockHash:       "0xe8e5f93f338348b17df97b4a6723ce4ee899eb375003c8c6c74255325915a1ed",
+			TransactionHash: "0xf9c4f7843dc1f9bf6d248ebe0033b2c51398255eb8973f4af4bae2c3f9313a78",
+			LogIndex:        "0x",
+		},
+		{
+			Address: "0x33990122638b9132ca29c723bdf037f1a891a70c",
+			Topics: []string{"0xf63780e752c6a54a94fc52715dbc5518a3b4c3c2833d301a204226548a2a8545",
+				"0x726f6f7473746f636b0000000000000000000000000000000000000000000000",
+				"0x000000000000000000000000697c0123cd103cf4c3446b271e0970f109eae78c"},
+			Data:            "0x",
+			BlockNumber:     "0x66650",
+			BlockHash:       "0x49dd65b6e2f97b294d18ec97e26b349b8215f26964be1f26e0639f79995b1a11",
+			TransactionHash: "0xb190139d14140cf98035c5b78fe3b2629db2787ef234258633278985fa99a13a",
+			LogIndex:        "0x",
+		},
+	}
+
+	tests := []struct {
+		name       string
+		page, off  int
+		wantSlice  []Log
+		wantErr    bool
+		errContain string
+	}{
+		{
+			name: "no page or offset returns all logs",
+			page: 0, off: 0,
+			wantSlice: expectedLogs,
+		},
+		{
+			name: "page=1, offset=0 returns all logs",
+			page: 1, off: 0,
+			wantSlice: expectedLogs,
+		},
+		{
+			name: "page=2, offset=0 returns all logs",
+			page: 2, off: 0,
+			wantSlice: expectedLogs,
+		},
+		{
+			name: "page=1, offset=2 returns first 2 logs of 4",
+			page: 1, off: 2,
+			wantSlice: expectedLogs[0:2],
+		},
+		{
+			name: "page=2, offset=2 returns last 2 logs of 4",
+			page: 2, off: 2,
+			wantSlice: expectedLogs[2:4],
+		},
+		{
+			name: "page=5, offset=1 returns no logs as page is beyond available logs",
+			page: 5, off: 1,
+			wantSlice:  []Log{},
+			wantErr:    true,
+			errContain: "No records found",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := api.GetLogs(
+				379224,
+				430000,
+				"0x33990122638b9132ca29c723bdf037f1a891a70c",
+				"0xf63780e752c6a54a94fc52715dbc5518a3b4c3c2833d301a204226548a2a8545",
+				WithPagination(tt.page, tt.off),
+			)
+
+			if tt.wantErr {
+				if err == nil {
+					t.Fatal("expected error, got nil")
+				}
+				if !strings.Contains(err.Error(), tt.errContain) {
+					t.Fatalf("expected error to contain %q, got %v", tt.errContain, err)
+				}
+				if len(got) != 0 {
+					t.Errorf("expected no logs on error, but got %d entries", len(got))
+				}
+				return
+			}
+
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if diff := cmp.Diff(tt.wantSlice, got); diff != "" {
+				t.Errorf("logs mismatch (-want +got):\n%s", diff)
+			}
+		})
+	}
+}