feat: include GPG support (#92)

Taskfile.yml

@@ -38,6 +38,12 @@ tasks:
     cmds:
       - go mod tidy
 
+  test:
+    desc: Run all of the tests
+    cmds:
+      - task: unit-test
+      - task: docker-test
+
   unit-test:
     desc: Run the unit tests
     vars:
@@ -47,6 +53,14 @@ tasks:
     cmds:
       - go test {{.TEST_OPTIONS}} -covermode=atomic -coverprofile={{.COVER_PROFILE}} {{.TEST_FORMAT}} ./...
 
+  docker-test:
+    desc: Run the docker-based tests
+    cmds:
+      - docker build . -t gitz-test:latest -f testdata/Dockerfile --build-arg test=tagsigned
+      - docker build . -t gitz-test:latest -f testdata/Dockerfile --build-arg test=tagsigningkey
+      - docker build . -t gitz-test:latest -f testdata/Dockerfile --build-arg test=commitsigned
+      - docker build . -t gitz-test:latest -f testdata/Dockerfile --build-arg test=commitsigningkey
+
   lint:
     desc: Lint the code using golangci-lint
     vars:

commit.go

@@ -22,10 +22,133 @@ SOFTWARE.
 
 package git
 
-import "fmt"
+import (
+	"fmt"
+	"strings"
+)
+
+// CommitOption provides a way for setting specific options during a commit
+// operation. Each supported option can customize the way the commit is
+// created against the current repository (working directory)
+type CommitOption func(*commitOptions)
+
+type commitOptions struct {
+	AllowEmpty    bool
+	ForceNoSigned bool
+	Signed        bool
+	SigningKey    string
+}
+
+// WithAllowEmpty allows a commit to be created without having to track
+// any changes. This bypasses the default protection by git, preventing
+// a commit from having the exact same tree as its parent
+func WithAllowEmpty() CommitOption {
+	return func(opts *commitOptions) {
+		opts.AllowEmpty = true
+	}
+}
+
+// WithGpgSign will create a GPG-signed commit using the GPG key associated
+// with the committers email address. Overriding this behavior is possible
+// through the user.signingkey config setting. This option does not need
+// to be explicitly called if the commit.gpgSign config setting is set to
+// true
+func WithGpgSign() CommitOption {
+	return func(opts *commitOptions) {
+		opts.Signed = true
+	}
+}
+
+// WithGpgSigningKey will create a GPG-signed commit using the provided GPG
+// key ID, overridding any default GPG key set by the user.signingKey git
+// config setting
+func WithGpgSigningKey(key string) CommitOption {
+	return func(opts *commitOptions) {
+		opts.Signed = true
+		opts.SigningKey = strings.TrimSpace(key)
+	}
+}
+
+// WithNoGpgSign ensures the created commit will not be GPG signed
+// regardless of the value assigned to the repositories commit.gpgSign
+// git config setting
+func WithNoGpgSign() CommitOption {
+	return func(opts *commitOptions) {
+		opts.ForceNoSigned = true
+	}
+}
 
 // Commit a snapshot of changes within the current repository (working directory)
-// and describe those changes with a given log message
-func (c *Client) Commit(msg string) (string, error) {
-	return c.exec(fmt.Sprintf("git commit -m '%s'", msg))
+// and describe those changes with a given log message. Commit behavior can be
+// customized through the use of options
+func (c *Client) Commit(msg string, opts ...CommitOption) (string, error) {
+	options := &commitOptions{}
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	var commitCmd strings.Builder
+	commitCmd.WriteString("git commit")
+
+	if options.AllowEmpty {
+		commitCmd.WriteString(" --allow-empty")
+	}
+
+	if options.Signed {
+		commitCmd.WriteString(" -S")
+	}
+
+	if options.SigningKey != "" {
+		commitCmd.WriteString(" --gpg-sign=" + options.SigningKey)
+	}
+
+	if options.ForceNoSigned {
+		commitCmd.WriteString(" --no-gpg-sign")
+	}
+
+	commitCmd.WriteString(fmt.Sprintf(" -m '%s'", msg))
+	return c.exec(commitCmd.String())
+}
+
+const (
+	authorPrefix    = "author "
+	committerPrefix = "committer "
+	emailEnd        = '>'
+)
+
+// CommitVerification contains details about a GPG signed commit
+type CommitVerification struct {
+	Sha         string
+	Author      Author
+	Committer   Author
+	Fingerprint string
+	SignedBy    *Author
+}
+
+// VerifyCommit validates that a given commit has a valid GPG signature
+// and returns details about that signature
+func (c *Client) VerifyCommit(sha string) (*CommitVerification, error) {
+	out, err := c.exec("git verify-commit -v " + sha)
+	if err != nil {
+		return nil, err
+	}
+
+	author := chompUntil(out[strings.Index(out, authorPrefix)+len(authorPrefix):], emailEnd)
+	committer := chompUntil(out[strings.Index(out, committerPrefix)+len(committerPrefix):], emailEnd)
+	fingerprint := chompCRLF(out[strings.Index(out, fingerprintPrefix)+len(fingerprintPrefix):])
+
+	var signedByAuthor *Author
+	if strings.Contains(out, signedByPrefix) {
+		signedBy := chompUntil(out[strings.Index(out, signedByPrefix)+len(signedByPrefix):], '"')
+		author := parseAuthor(signedBy)
+		signedByAuthor = &author
+	}
+
+	return &CommitVerification{
+		Sha:         sha,
+		Author:      parseAuthor(author),
+		Committer:   parseAuthor(committer),
+		Fingerprint: fingerprint,
+		SignedBy:    signedByAuthor,
+	}, nil
 }

commit_test.go

@@ -45,15 +45,22 @@ func TestCommit(t *testing.T) {
 	assert.Equal(t, lastCommit.Message, "this is an example commit message")
 }
 
-func TestCommitCleanWorkingTreeError(t *testing.T) {
+func TestCommitWithAllowEmpty(t *testing.T) {
 	gittest.InitRepository(t)
 
 	client, _ := git.NewClient()
-	_, err := client.Commit("this is an example commit message")
+	_, err := client.Commit("this will be a an empty commit", git.WithAllowEmpty())
+
+	require.NoError(t, err)
+}
 
-	var errGit git.ErrGitExecCommand
-	require.ErrorAs(t, err, &errGit)
+func TestCommitWithNoGpgSign(t *testing.T) {
+	gittest.InitRepository(t, gittest.WithFiles("test.txt"))
+	gittest.ConfigSet(t, "user.signingkey", "DOES-NOT-EXIST", "commit.gpgsign", "true")
+	gittest.StageFile(t, "test.txt")
 
-	assert.Equal(t, "git commit -m 'this is an example commit message'", errGit.Cmd)
-	assert.Contains(t, errGit.Out, "nothing to commit, working tree clean")
+	client, _ := git.NewClient()
+	_, err := client.Commit("this will be a regular commit", git.WithNoGpgSign())
+
+	require.NoError(t, err)
 }

go.mod

@@ -11,7 +11,8 @@ require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	golang.org/x/sync v0.1.0 // indirect
-	golang.org/x/sys v0.3.0 // indirect
-	golang.org/x/term v0.3.0 // indirect
+	golang.org/x/sys v0.7.0 // indirect
+	golang.org/x/term v0.5.0 // indirect
+	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -4,7 +4,10 @@ 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/frankban/quicktest v1.14.4 h1:g2rn0vABPOOXmZUj+vbmUp0lPoXEMuhTpIluN0XL9UY=
 github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
@@ -18,12 +21,13 @@ github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ
 github.com/stretchr/testify v1.8.2/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
 golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sys v0.3.0 h1:w8ZOecv6NaNa/zC8944JTU3vz4u6Lagfk4RPQxv92NQ=
-golang.org/x/sys v0.3.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/term v0.3.0 h1:qoo4akIqOcDME5bhc/NgxUdovd6BSS2uMsVjB56q1xI=
-golang.org/x/term v0.3.0/go.mod h1:q750SLmJuPmVoN1blW3UFBPREJfb1KmY3vwxfr+nFDA=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+golang.org/x/sys v0.7.0 h1:3jlCCIQZPdOYu1h8BkNvLz8Kgwtae2cagcG/VamtZRU=
+golang.org/x/sys v0.7.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.5.0 h1:n2a8QNdAb0sZNpU9R1ALUXBbY+w51fCQDN+7EdxNBsY=
+golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 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=