synapsecns/sanguine

package git

import (
    "context"
    "encoding/json"
    "fmt"
    "github.com/avast/retry-go"
    "github.com/google/go-github/v41/github"
    "github.com/synapsecns/sanguine/contrib/git-changes-action/detector/actionscore"
    "github.com/synapsecns/sanguine/contrib/git-changes-action/detector/tree"
    "golang.org/x/exp/slices"
    "golang.org/x/oauth2"
    "os"
    "strings"
    "time"
)

// GetChangeTree returns the ref for the given event name.
// it is based on  https://github.com/dorny/paths-filter/blob/4067d885736b84de7c414f582ac45897079b0a78/src/main.ts#L36
func GetChangeTree(ctx context.Context, repoPath, ref, token, base string) (tree.Tree, error) {
    ghContext := actionscore.NewContext()

    ts := oauth2.StaticTokenSource(
        &oauth2.Token{AccessToken: token})

    tc := oauth2.NewClient(ctx, ts)

    client := github.NewClient(tc)

    isPrEvent := slices.ContainsFunc([]EventType{EventPullRequest, EventPullRequestReview, EventPullRequestReviewComment, EventPullRequestTarget}, func(eventType EventType) bool {
        return strings.EqualFold(ghContext.EventName, eventType.String())
    })

    if isPrEvent {
        return getChangedFilesFromAPI(ctx, ghContext, client)
    }

    ct, err := getChangeTreeFromGit(repoPath, ghContext, ref, base)
    if err != nil {
        return nil, fmt.Errorf("could not get change tree: %w", err)
    }
    return ct, nil
}

// nolint: cyclop
func getChangedFilesFromAPI(ctx context.Context, ghContext *actionscore.Context, client *github.Client) (ct tree.Tree, err error) {
    var gpe github.PullRequestEvent
    // TODO: should rap into context
    f, err := os.Open(os.Getenv("GITHUB_EVENT_PATH"))
    if err != nil {
        return nil, fmt.Errorf("could not open event path: %w", err)
    }
    defer func() {
        _ = f.Close()
    }()

    if err := json.NewDecoder(f).Decode(&gpe); err != nil {
        return nil, fmt.Errorf("could not decode event: %w", err)
    }

    repoOwner, repoName := ghContext.Repo()

    prNumber := gpe.GetPullRequest().GetNumber()

    ct = tree.NewTree()

    page := 1
    const retryCount = 10
    const perPage = 100
    for {
        var files []*github.CommitFile
        var res *github.Response
        err = retry.Do(func() error {
            reqCtx, cancel := context.WithTimeout(ctx, 15*time.Second)
            defer cancel()

            files, res, err = client.PullRequests.ListFiles(reqCtx, repoOwner, repoName, prNumber, &github.ListOptions{
                Page:    page,
                PerPage: perPage,
            })
            if err != nil {
                return fmt.Errorf("could not get files for repoOwner %s, repoName %s, prNumber %d, page number %d with page size %d: %w",
                    repoOwner, repoName, prNumber, page, perPage, err)
            }
            return nil
        }, retry.Context(ctx), retry.Attempts(retryCount))
        if err != nil {
            return nil, fmt.Errorf("could not get files after %d retries: %w", retryCount, err)
        }

        for _, file := range files {
            if file.Filename != nil {
                ct.Add(file.GetFilename())
            }
            if file.PreviousFilename != nil {
                ct.Add(file.GetPreviousFilename())
            }
        }

        if res.NextPage == 0 {
            break
        }

        page = res.NextPage
    }

    return ct, nil
}

// EventType is the type of github api event.
//
//go:generate go run golang.org/x/tools/cmd/stringer -type=EventType -linecomment
type EventType uint8

const (
    // EventPullRequest is a pull request event.
    EventPullRequest EventType = iota // pull_request
    // EventPush is a push event.
    EventPush // push
    // EventRelease is a release event.
    EventRelease // release
    // EventTag is a tag event.
    EventTag // tag
    // EventPullRequestReview is a pull request review event.
    EventPullRequestReview // pull_request_review
    // EventPullRequestReviewComment is a pull request review comment event.
    EventPullRequestReviewComment // pull_request_review_comment
    // EventPullRequestTarget is a pull request target event.
    EventPullRequestTarget // pull_request_target
    // EventIssueComment is an issue comment event.
    EventIssueComment // issue_comment
    // EventIssues is an issues event.
    EventIssues // issues
    // EventCreate is a create event.
    EventCreate // create
    // EventDelete is a delete event.
    EventDelete // delete
    // EventDeployment is a deployment event.
    EventDeployment // deployment
)