initial commit

Author: brainexe

.gitignore

@@ -0,0 +1,5 @@
+vendor
+go.sum
+git-log-exec
+out.csv
+.idea

Makefile

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+
+go-log-exec:
+	go build -o go-log-exec *.go

git.go

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+package main
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+func getCommits(branch string, limit int, after string, before string) ([]entry, error) {
+	checkout(branch)
+
+	args := []string{
+		"log",
+		"--pretty=\"%h %ct\"",
+	}
+	if after != "" {
+		args = append(args, fmt.Sprintf("--from='%s'", after))
+	}
+	if before != "" {
+		args = append(args, fmt.Sprintf("--before='%s'", before))
+	}
+
+	stdout, err := execute("git", args...)
+
+	commits := make([]entry, 0)
+	if err != nil {
+		return commits, err
+	}
+
+	lines := strings.Split(stdout, "\n")
+
+	stepSize := (len(lines) / limit) - 1
+	if stepSize == 0 {
+		stepSize = 1
+	}
+
+	for i, line := range lines {
+		if line == "" {
+			continue
+		}
+		if i%stepSize != 0 {
+			continue
+		}
+		parts := strings.Split(strings.ReplaceAll(line, "\"", ""), " ")
+		timestamp, _ := strconv.Atoi(parts[1])
+		commits = append(commits, entry{
+			commit:    parts[0],
+			timestamp: timestamp,
+		})
+	}
+
+	fmt.Printf("Commits: %d, Step size: %d (%d commits to check)\n", len(lines), stepSize, len(commits))
+
+	return commits, nil
+}
+
+func checkout(branch string) error {
+	_, err := execute("git", "checkout", branch)
+
+	return err
+}

go.mod

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+module github.com/brainexe/git-log-exec
+
+go 1.13
+
+require github.com/schollz/progressbar/v2 v2.15.0

main.go

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+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/schollz/progressbar/v2"
+)
+
+type entry struct {
+	commit    string
+	timestamp int
+	data      string
+}
+
+var directory string
+var command string
+var branch string
+var outputFile string
+var limit int
+var after string
+var before string
+
+func main() {
+	flag.StringVar(&directory, "directory", "", "git workspace (by default current directory)")
+	flag.StringVar(&command, "command", "", "command to execute")
+	flag.StringVar(&branch, "branch", "master", "git branch to check")
+	flag.StringVar(&outputFile, "output", "out.csv", "output csv file")
+	flag.StringVar(&after, "after", "", "optional begin date of history search")
+	flag.StringVar(&before, "before", "", "optional end date of history search")
+	flag.IntVar(&limit, "limit", 500, "max number of commits to check")
+	flag.Parse()
+
+	// if no parameter given, use history of current history
+	var err error
+	if directory == "" {
+		directory, err = os.Getwd()
+		checkError(err)
+	}
+
+	if stat, err := os.Stat(directory); err != nil || !stat.IsDir() {
+		fmt.Printf("Invalid directory: %s\n", directory)
+		flag.PrintDefaults()
+		os.Exit(1)
+	}
+
+	commits, err := getCommits(branch, limit, after, before)
+	checkError(err)
+
+	bar := progressbar.New(len(commits))
+	result := make([]entry, 0, len(commits))
+
+	for _, commit := range commits {
+		bar.Add(1)
+		result = append(result, evaluate(commit))
+	}
+
+	// checkout to initial version
+	checkout(branch)
+
+	out, err := os.Create(outputFile)
+	checkError(err)
+	defer out.Close()
+
+	err = writeCsv(result, out)
+	checkError(err)
+	fmt.Printf("\nWrote file %s\n", outputFile)
+}
+
+func checkError(err error) {
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+func evaluate(commit entry) entry {
+	checkout(commit.commit)
+
+	stdout, _ := execute("sh", "-c", command)
+
+	commit.data = strings.TrimSpace(stdout)
+
+	return commit
+}
+
+func execute(name string, args ...string) (string, error) {
+	cmd := exec.Command(name, args...)
+	cmd.Dir = directory
+	out, err := cmd.CombinedOutput()
+
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Command '%s' failed: %s: %s", cmd.String(), err, string(out))
+		os.Exit(1)
+	}
+
+	return string(out), err
+}

readme.md

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+# git-log-exec
+Executes any bash command on the whole git history and produces a CSV file out of it. 
+
+**Usecases:**
+- LOC/files over time
+- trend of build/compile time
+- trend of technical dept (e.g. search for certain method calls)
+
+## Example
+```
+cd ~/projects/home-assistant
+git-log-exec -out loc.csv -command="find homeassistant -type f | wc -l" 
+```
+
+**Result**
+```
+time,result,commit
+2019-12-22T23:41:22+01:00,12064,48d35a455
+2019-12-04T00:46:38+01:00,12052,564c468c2
+2019-11-27T20:52:03+01:00,12006,d7a66e6e4
+2019-11-25T04:57:40+01:00,11876,c38240673
+2019-11-13T15:32:22+01:00,11876,15ce73835
+2019-11-03T20:36:02+01:00,11779,5fd9b474d
+2019-10-25T01:42:54+02:00,11666,643b3a98e
+2019-10-21T09:55:53+02:00,11607,c1fccee83
+2019-10-17T15:03:05+02:00,11551,8350e1246
+2019-10-12T21:57:18+02:00,11486,17b1ba2e9
+2019-10-07T21:49:54+02:00,11420,1febb32dd
+``` 
+
+## Options
+```
+  -command string
+    	command to execute
+  -directory string
+    	git workspace (by default current directory)
+  -limit int
+    	max number of commits to check (default 500)
+  -branch string
+    	git branch to check (default "master")
+  -output string
+    	output csv file (default "out.csv")
+  -after string
+    	optional begin date of history search
+  -before string
+    	optional end date of history search
+``` 

writer.go

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+package main
+
+import (
+	"encoding/csv"
+	"io"
+	"time"
+)
+
+func writeCsv(logs []entry, file io.Writer) error {
+	// todo sort by time
+
+	csvwriter := csv.NewWriter(file)
+	csvwriter.Write([]string{
+		"time",
+		"result",
+		"commit",
+	})
+	for _, row := range logs {
+		err := csvwriter.Write([]string{
+			time.Unix(int64(row.timestamp), 0).Format(time.RFC3339),
+			row.data,
+			row.commit,
+		})
+		if err != nil {
+			return err
+		}
+	}
+
+	csvwriter.Flush()
+
+	return nil
+}