Select last block from db with server

db/server/go.mod

@@ -1,3 +1,20 @@
 module moonstreamdb
 
 go 1.17
+
+require (
+	github.com/jackc/chunkreader/v2 v2.0.1 // indirect
+	github.com/jackc/pgconn v1.10.0 // indirect
+	github.com/jackc/pgio v1.0.0 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgproto3/v2 v2.1.1 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20200714003250-2b9c44734f2b // indirect
+	github.com/jackc/pgtype v1.8.1 // indirect
+	github.com/jackc/pgx/v4 v4.13.0 // indirect
+	github.com/jinzhu/inflection v1.0.0 // indirect
+	github.com/jinzhu/now v1.1.2 // indirect
+	golang.org/x/crypto v0.0.0-20210817164053-32db794688a5 // indirect
+	golang.org/x/text v0.3.7 // indirect
+	gorm.io/driver/postgres v1.1.1 // indirect
+	gorm.io/gorm v1.21.15 // indirect
+)

db/server/main.go

@@ -3,24 +3,51 @@ package main
 import (
 	"encoding/json"
 	"fmt"
+	"log"
 	"net/http"
+	"os"
+
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
 )
 
 type PingResponse struct {
 	Status string `json:"status"`
 }
 
+type BlockResponse struct {
+	BlockNumber uint64 `json:"block_number"`
+}
+
 func ping(w http.ResponseWriter, req *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 	response := PingResponse{Status: "ok"}
 	json.NewEncoder(w).Encode(response)
 }
 
+func blockLatest(w http.ResponseWriter, req *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+
+	var latestBlock BlockResponse
+
+	MOONSTREAM_DB_URI := os.Getenv("MOONSTREAM_DB_URI")
+	db, err := gorm.Open(postgres.Open(MOONSTREAM_DB_URI), &gorm.Config{})
+	if err != nil {
+		log.Print(err)
+	}
+
+	query := "SELECT block_number FROM ethereum_blocks ORDER BY block_number DESC LIMIT 1"
+	db.Raw(query, 1).Scan(&latestBlock.BlockNumber)
+
+	json.NewEncoder(w).Encode(latestBlock)
+}
+
 func main() {
 	address := "0.0.0.0:8931"
 	fmt.Printf("Starting server at %s\n", address)
 
 	http.HandleFunc("/ping", ping)
+	http.HandleFunc("/block/latest", blockLatest)
 
 	http.ListenAndServe(address, nil)
 }