Added deployments overview

backend/app/github/github.go

@@ -2,6 +2,7 @@ package github
 
 import (
 	"archive/zip"
+	"encoding/json"
 	"fmt"
 	"io"
 	"io/fs"
@@ -11,7 +12,67 @@ import (
 	"strings"
 )
 
-func FetchAndDeployBranch(repoOwner, repoName, branch, pat, destDir string) error {
+// DeployResult holds metadata about the deployed commit.
+type DeployResult struct {
+	CommitHash    string `json:"commit_hash"`
+	CommitMessage string `json:"commit_message"`
+}
+
+func FetchAndDeployBranch(repoOwner, repoName, branch, pat, destDir string) (*DeployResult, error) {
+	result, err := fetchBranchHead(repoOwner, repoName, branch, pat)
+	if err != nil {
+		return nil, fmt.Errorf("fetching branch head: %w", err)
+	}
+
+	if err = downloadAndExtract(repoOwner, repoName, branch, pat, destDir); err != nil {
+		return nil, err
+	}
+
+	return result, nil
+}
+
+// fetchBranchHead returns the SHA and commit message for the tip of the given branch.
+func fetchBranchHead(owner, repo, branch, pat string) (*DeployResult, error) {
+	url := fmt.Sprintf(
+		"https://api.github.com/repos/%s/%s/commits/%s",
+		owner, repo, branch,
+	)
+
+	req, err := http.NewRequest(http.MethodGet, url, nil)
+	if err != nil {
+		return nil, fmt.Errorf("creating request: %w", err)
+	}
+	req.Header.Set("Authorization", "Bearer "+pat)
+	req.Header.Set("Accept", "application/vnd.github+json")
+	req.Header.Set("X-GitHub-Api-Version", "2022-11-28")
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("fetching commit: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("GitHub returned %s for %s", resp.Status, url)
+	}
+
+	var payload struct {
+		SHA    string `json:"sha"`
+		Commit struct {
+			Message string `json:"message"`
+		} `json:"commit"`
+	}
+	if err = json.NewDecoder(resp.Body).Decode(&payload); err != nil {
+		return nil, fmt.Errorf("decoding commit response: %w", err)
+	}
+
+	return &DeployResult{
+		CommitHash:    payload.SHA,
+		CommitMessage: strings.SplitN(payload.Commit.Message, "\n", 2)[0],
+	}, nil
+}
+
+func downloadAndExtract(repoOwner, repoName, branch, pat, destDir string) error {
 	archiveURL := fmt.Sprintf(
 		"https://api.github.com/repos/%s/%s/zipball/%s",
 		repoOwner, repoName, branch,
@@ -59,7 +120,7 @@ func FetchAndDeployBranch(repoOwner, repoName, branch, pat, destDir string) erro
 		return fmt.Errorf("unzipping: %w", err)
 	}
 
-	// github wraps everything in one top-level folder ({owner}-{repo}-{sha}/).
+	// GitHub wraps everything in one top-level folder ({owner}-{repo}-{sha}/).
 	entries, err := os.ReadDir(tmpDir)
 	if err != nil {
 		return fmt.Errorf("reading temp dir: %w", err)