add buffered channel methods

cmd/mgfetch/mgfetch.go

@@ -14,7 +14,7 @@ type Repo git.Repository
 func main() {
 	year := time.Now().Year() - 1
 	authors := []string{"Groot"}
-	gfreq, err := commits.GlobalFrequency(year, authors)
+	gfreq, err := commits.GlobalFrequencyChan(year, authors)
 	if err != nil {
 		panic(err)
 	}

commits/commits.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"os"
 	"regexp"
+	"sync"
 	"time"
 
 	git "github.com/go-git/go-git/v5"
@@ -15,6 +16,53 @@ import (
 
 type Repo git.Repository
 
+func GlobalFrequencyChan(year int, authors []string) (types.YearFreq, error) {
+	yearLength := 365
+	if year%4 == 0 {
+		yearLength++
+	}
+	mrconf, err := parse.LoadMRConfig()
+	if err != nil {
+		return types.YearFreq{}, err
+	}
+	paths := mrconf.GetRepoPaths()
+	outChan := make(chan types.Commit, 10)
+	var wg sync.WaitGroup
+	for _, p := range paths {
+		wg.Add(1)
+		go func(path string) {
+			repo, err := OpenRepo(path)
+			if err != nil {
+				return
+			}
+			cc, err := repo.GetCommitChan()
+			if err != nil {
+				return
+			}
+			cc = FilterCChanByYear(cc, year)
+			cc, err = FilterCChanByAuthor(cc, authors)
+			if err != nil {
+				return
+			}
+			for c := range cc {
+				outChan <- c
+			}
+			wg.Done()
+		}(p)
+	}
+	go func() {
+		wg.Wait()
+		close(outChan)
+	}()
+	commitSet := CommitSet{Year: year, Commits: []types.Commit{}}
+	for c := range outChan {
+		commitSet.Commits = append(commitSet.Commits, c)
+	}
+	freq := commitSet.ToYearFreq()
+
+	return freq, nil
+}
+
 func GlobalFrequency(year int, authors []string) (types.YearFreq, error) {
 	yearLength := 365
 	if year%4 == 0 {
@@ -128,6 +176,67 @@ func (cs CommitSet) FilterByYear(year int) CommitSet {
 	return newCS
 }
 
+func FilterCChanByYear(in chan types.Commit, year int) chan types.Commit {
+	out := make(chan types.Commit, 30)
+	go func() {
+		for commit := range in {
+			if commit.TimeStamp.Year() == year {
+				out <- commit
+			}
+		}
+		close(out)
+	}()
+	return out
+}
+
+func FilterCChanByAuthor(in chan types.Commit, authors []string) (chan types.Commit, error) {
+	out := make(chan types.Commit, 30)
+	regSet := [](*regexp.Regexp){}
+	for _, a := range authors {
+		r, err := regexp.Compile(a)
+		if err != nil {
+			close(out)
+			return out, err
+		}
+		regSet = append(regSet, r)
+	}
+	go func() {
+		for commit := range in {
+			for _, r := range regSet {
+				if r.MatchString(commit.Author) {
+					out <- commit
+					break
+				}
+			}
+		}
+		close(out)
+	}()
+	return out, nil
+}
+
+func (repo Repo) GetCommitChan() (chan types.Commit, error) {
+	cc := make(chan types.Commit, 30)
+	r := git.Repository(repo)
+	ref, err := r.Head()
+	if err != nil {
+		return cc, err
+	}
+	cIter, err := r.Log(&git.LogOptions{From: ref.Hash()})
+	if err != nil {
+		return cc, err
+	}
+	go func() {
+		cIter.ForEach(func(c *object.Commit) error {
+			ts := c.Author.When
+			commit := types.Commit{Author: c.Author.Name, Message: c.Message, TimeStamp: ts}
+			cc <- commit
+			return nil
+		})
+		close(cc)
+	}()
+	return cc, nil
+}
+
 func (repo Repo) GetCommitSet() (CommitSet, error) {
 	cs := CommitSet{}
 	commits := []types.Commit{}