Add write file (#4)

Author: kelindar

.github/workflows/test.yml

@@ -11,7 +11,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v1
         with:
-          go-version: 1.16
+          go-version: 1.19
       - name: Check out code
         uses: actions/checkout@v2
       - name: Install dependencies

go.mod

@@ -1,14 +1,14 @@
 module github.com/kelindar/tile
 
-go 1.17
+go 1.19
 
 require (
-	github.com/kelindar/iostream v1.2.0
-	github.com/stretchr/testify v1.7.0
+	github.com/kelindar/iostream v1.3.0
+	github.com/stretchr/testify v1.8.1
 )
 
 require (
-	github.com/davecgh/go-spew v1.1.0 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,13 +1,19 @@
-github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/kelindar/iostream v1.2.0 h1:UaFLsj/0quGMZxI/rpHmI8u7vNKY9xSyw4mQ9YCTPWA=
-github.com/kelindar/iostream v1.2.0/go.mod h1:MkjMuVb6zGdPQVdwLnFRO0xOTOdDvBWTztFmjRDQkXk=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/kelindar/iostream v1.3.0 h1:Bz2qQabipZlF1XCk64bnxsGLete+iHtayGPeWVpbwbo=
+github.com/kelindar/iostream v1.3.0/go.mod h1:MkjMuVb6zGdPQVdwLnFRO0xOTOdDvBWTztFmjRDQkXk=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
-github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
+github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

store.go

@@ -4,14 +4,18 @@
 package tile
 
 import (
+	"compress/flate"
 	"encoding/binary"
 	"io"
+	"os"
 
 	"github.com/kelindar/iostream"
 )
 
 const tileDataSize = 54
 
+// ---------------------------------- Stream ----------------------------------
+
 // WriteTo writes the grid to a specific writer.
 func (m *Grid) WriteTo(dst io.Writer) (n int64, err error) {
 	p1 := At(0, 0)
@@ -64,3 +68,41 @@ func ReadFrom(src io.Reader) (grid *Grid, err error) {
 	})
 	return
 }
+
+// ---------------------------------- File ----------------------------------
+
+// WriteFile writes the grid into a flate-compressed binary file.
+func (m *Grid) WriteFile(filename string) error {
+	file, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+
+	defer file.Close()
+	writer, err := flate.NewWriter(file, flate.BestSpeed)
+	if err != nil {
+		return err
+	}
+
+	// WriteTo the underlying writer
+	defer writer.Close()
+	_, err = m.WriteTo(writer)
+	return err
+}
+
+// Restore restores the grid from the specified file. The grid must
+// be written using the corresponding WriteFile() method.
+func ReadFile(filename string) (grid *Grid, err error) {
+	if _, err := os.Stat(filename); os.IsNotExist(err) {
+		return nil, os.ErrNotExist
+	}
+
+	// Otherwise, attempt to open the file and restore
+	file, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	defer file.Close()
+	return ReadFrom(flate.NewReader(file))
+}

store_test.go

@@ -6,6 +6,7 @@ package tile
 import (
 	"bytes"
 	"compress/flate"
+	"os"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -78,3 +79,19 @@ func TestSaveLoadFlate(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, m.pages, out.pages)
 }
+
+func TestSaveLoadFile(t *testing.T) {
+	temp, err := os.CreateTemp("", "*")
+	assert.NoError(t, err)
+	defer os.Remove(temp.Name())
+
+	println(temp.Name())
+	// Write a test map into temp file
+	m := mapFrom("300x300.png")
+	assert.NoError(t, m.WriteFile(temp.Name()))
+
+	// Read the map back
+	out, err := ReadFile(temp.Name())
+	assert.NoError(t, err)
+	assert.Equal(t, m.pages, out.pages)
+}