init

internal/storage/dao/database_error.go

@@ -0,0 +1,32 @@
+package dao
+
+import (
+	"fmt"
+)
+
+type Type int
+
+const (
+	ErrTypeNotFound Type = iota
+	ErrTypeDuplicate
+	ErrTypeForeignKeyViolation
+)
+
+type Error struct {
+	Cause error
+	Type  Type
+}
+
+func NewDAOError(t Type, cause error) error {
+	return &Error{
+		Type:  t,
+		Cause: cause,
+	}
+}
+
+func (e *Error) Error() string {
+	if e.Cause != nil {
+		return fmt.Sprintf("Type %d: %s", e.Type, e.Cause.Error())
+	}
+	return fmt.Sprintf("Type %d: no cause given", e.Type)
+}

internal/storage/dao/postgresql/database_postgresql.go

@@ -0,0 +1,43 @@
+package postgresql
+
+import (
+	"database/sql"
+	"fmt"
+	"github.com/kratisto/mam-contract/internal/storage/dao"
+	"github.com/kratisto/mam-contract/internal/utils"
+
+	"github.com/lib/pq"
+)
+
+const (
+	pgCodeUniqueViolation     = "23505"
+	pgCodeForeingKeyViolation = "23503"
+)
+
+func HandlePgError(e *pq.Error) error {
+	if e.Code == pgCodeUniqueViolation {
+		return dao.NewDAOError(dao.ErrTypeDuplicate, e)
+	}
+
+	if e.Code == pgCodeForeingKeyViolation {
+		return dao.NewDAOError(dao.ErrTypeForeignKeyViolation, e)
+	}
+	return e
+}
+
+type DatabasePostgreSQL struct {
+	Session *sql.DB
+}
+
+func NewDatabasePostgreSQL(connectionURI string) *DatabasePostgreSQL {
+	db, err := sql.Open("postgres", connectionURI)
+	if err != nil {
+		utils.GetLogger().WithError(err).Fatal("Unable to get a connection to the postgres db")
+	}
+	err = db.Ping()
+	if err != nil {
+		fmt.Println(err)
+		utils.GetLogger().WithError(err).Fatal("Unable to ping the postgres db")
+	}
+	return &DatabasePostgreSQL{Session: db}
+}

internal/storage/dao/postgresql/setup.go

@@ -0,0 +1,13 @@
+package postgresql
+
+import (
+	"github.com/kratisto/mam-contract/internal/utils"
+)
+
+var DatabaseKey = "POSTGRES"
+
+func Setup(injector *utils.Injector, connectionUri string) {
+	database := NewDatabasePostgreSQL(connectionUri)
+
+	injector.Set(DatabaseKey, database)
+}