From 02d614432874557cf725b99b984270f9e2ef6fe8 Mon Sep 17 00:00:00 2001
From: Isaac Guerreiro <ig00114@saqueepague.com.br>
Date: Tue, 24 Aug 2021 02:35:21 -0300
Subject: [PATCH 1/2] Some helper functions for in download check if blake3
 file already exist for some file, check if they're the same and choose if you
 want to update or not

---
 cmd/update.go      | 43 +++++++++++++++++++++++++++++++++++++++++++
 cmd/update_test.go | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 76 insertions(+)
 create mode 100644 cmd/update.go
 create mode 100644 cmd/update_test.go

diff --git a/cmd/update.go b/cmd/update.go
new file mode 100644
index 0000000..ce94cee
--- /dev/null
+++ b/cmd/update.go
@@ -0,0 +1,43 @@
+package cmd
+
+import (
+	"bytes"
+	"io"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"lukechampine.com/blake3"
+)
+
+func CreateCheckSumFile(writePath string, filename string, reader io.ReadCloser) {
+	fileExtBlake3 := addBlakeExtension(filename)
+	file, _ := os.Create(filepath.Join(writePath, fileExtBlake3))
+	var fileBytes []byte
+	fileBytes, _ = ioutil.ReadAll(reader)
+	byteHash := blake3.Sum256(fileBytes)
+
+	hashReader := bytes.NewReader(byteHash[:])
+
+	if _, err := io.Copy(file, hashReader); err != nil { // that side effect I mentioned in the above for loop makes this possible to do out of loop.
+		log.Fatal(err)
+	}
+}
+
+func isEqualFiles(writePath string, filename string, reader io.ReadCloser) bool {
+	fileExtBlake3 := addBlakeExtension(filename)
+	previousHash, _ := ioutil.ReadFile(filepath.Join(writePath, fileExtBlake3))
+	var fileBytes []byte
+	fileBytes, _ = ioutil.ReadAll(reader)
+	newHash := blake3.Sum256(fileBytes)
+	return bytes.Equal(previousHash, newHash[:])
+}
+
+func addBlakeExtension(fileName string) string {
+	if pos := strings.LastIndexByte(fileName, '.'); pos != -1 {
+		return fileName[:pos] + ".blake3"
+	}
+	return fileName + ".blake3"
+}
diff --git a/cmd/update_test.go b/cmd/update_test.go
new file mode 100644
index 0000000..0fe2e64
--- /dev/null
+++ b/cmd/update_test.go
@@ -0,0 +1,33 @@
+package cmd
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+)
+
+func ExampleCreateCheckSumFile() {
+	response, err := http.Get("https://ftp.expasy.org/databases/rhea/rdf/rhea.rdf.gz")
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	defer response.Body.Close()
+
+	CreateCheckSumFile("../data/build", "rhea.rdf.gz", response.Body)
+	fmt.Println("Hello")
+	// Output: Hell
+}
+
+func ExampleIsEqualFiles() {
+	response, err := http.Get("https://ftp.expasy.org/databases/rhea/rdf/rhea.rdf.gz")
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	defer response.Body.Close()
+	fmt.Println(isEqualFiles("../data/build", "rhea.rdf.gz", response.Body))
+	//Output: true
+}

From 15f9661f02a86eb1c2257462b0703ecbd2ad106c Mon Sep 17 00:00:00 2001
From: Isaac Guerreiro <ig00114@saqueepague.com.br>
Date: Tue, 7 Sep 2021 21:35:27 -0300
Subject: [PATCH 2/2] Go mod and test function updated

---
 cmd/update_test.go         | 14 --------------
 data/build/rhea.rdf.blake3 |  2 ++
 go.mod                     |  1 +
 3 files changed, 3 insertions(+), 14 deletions(-)
 create mode 100644 data/build/rhea.rdf.blake3

diff --git a/cmd/update_test.go b/cmd/update_test.go
index 0fe2e64..0691aa3 100644
--- a/cmd/update_test.go
+++ b/cmd/update_test.go
@@ -6,20 +6,6 @@ import (
 	"net/http"
 )
 
-func ExampleCreateCheckSumFile() {
-	response, err := http.Get("https://ftp.expasy.org/databases/rhea/rdf/rhea.rdf.gz")
-
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	defer response.Body.Close()
-
-	CreateCheckSumFile("../data/build", "rhea.rdf.gz", response.Body)
-	fmt.Println("Hello")
-	// Output: Hell
-}
-
 func ExampleIsEqualFiles() {
 	response, err := http.Get("https://ftp.expasy.org/databases/rhea/rdf/rhea.rdf.gz")
 
diff --git a/data/build/rhea.rdf.blake3 b/data/build/rhea.rdf.blake3
new file mode 100644
index 0000000..a3057f7
--- /dev/null
+++ b/data/build/rhea.rdf.blake3
@@ -0,0 +1,2 @@
+�䊰*Mg�T5p2
+k�-��||">�T�!�ro:
\ No newline at end of file
diff --git a/go.mod b/go.mod
index c646280..1bdc0f8 100644
--- a/go.mod
+++ b/go.mod
@@ -22,4 +22,5 @@ require (
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 	gopkg.in/ini.v1 v1.62.0 // indirect
 	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b // indirect
+	lukechampine.com/blake3 v1.0.0 // indirect
 )