Add first high-level integration test for Executor (#331)

* Add first high-level integration test for Executor

* Exec bash process in dummydocker

* Bump executor timeout to 5s in integration test

* add docker.exec symlink for windows

* Use OS-specific path separator when setting PATH

* .exe to .bat

* Try cd'ing into bat file directory

* Skip integration test on windows

Author: mrnugget

internal/campaigns/executor_test.go

@@ -0,0 +1,163 @@
+package campaigns
+
+import (
+	"archive/zip"
+	"bytes"
+	"context"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"mime"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"runtime"
+	"testing"
+	"time"
+
+	"github.com/sourcegraph/go-diff/diff"
+	"github.com/sourcegraph/src-cli/internal/api"
+	"github.com/sourcegraph/src-cli/internal/campaigns/graphql"
+)
+
+func TestExecutor_Integration(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("Test doesn't work on Windows because dummydocker is written in bash")
+	}
+
+	addToPath(t, "testdata/dummydocker")
+
+	repo := &graphql.Repository{
+		Name: "github.com/sourcegraph/src-cli",
+		DefaultBranch: &graphql.Branch{
+			Name:   "main",
+			Target: struct{ OID string }{OID: "d34db33f"},
+		},
+	}
+
+	filesInRepo := map[string]string{
+		"README.md": "# Welcome to the README\n",
+		"main.go":   "package main\n\nfunc main() {\n\tfmt.Println(     \"Hello World\")\n}\n",
+	}
+
+	steps := []Step{
+		{Run: `echo -e "foobar\n" >> README.md`, Container: "alpine:13"},
+		{Run: `go fmt main.go`, Container: "doesntmatter:13"},
+	}
+
+	h := newZipHandler(t, repo.Name, repo.DefaultBranch.Name, filesInRepo)
+	ts := httptest.NewServer(h)
+	defer ts.Close()
+
+	var clientBuffer bytes.Buffer
+	client := api.NewClient(api.ClientOpts{Endpoint: ts.URL, Out: &clientBuffer})
+
+	testTempDir, err := ioutil.TempDir("", "executor-integration-test-*")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	creator := &WorkspaceCreator{dir: testTempDir, client: client}
+	opts := ExecutorOpts{
+		Cache:       &ExecutionNoOpCache{},
+		Creator:     creator,
+		TempDir:     testTempDir,
+		Parallelism: runtime.GOMAXPROCS(0),
+		Timeout:     5 * time.Second,
+	}
+
+	called := false
+	updateFn := func(task *Task, ts TaskStatus) { called = true }
+
+	executor := newExecutor(opts, client, updateFn)
+
+	template := &ChangesetTemplate{}
+	executor.AddTask(repo, steps, template)
+
+	executor.Start(context.Background())
+	specs, err := executor.Wait()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !called {
+		t.Fatalf("update was not called")
+	}
+
+	if have, want := len(specs), 1; have != want {
+		t.Fatalf("wrong number of specs. want=%d, have=%d", want, have)
+	}
+
+	if have, want := len(specs[0].Commits), 1; have != want {
+		t.Fatalf("wrong number of commits. want=%d, have=%d", want, have)
+	}
+
+	fileDiffs, err := diff.ParseMultiFileDiff([]byte(specs[0].Commits[0].Diff))
+	if err != nil {
+		t.Fatalf("failed to parse diff: %s", err)
+	}
+
+	diffsByName := map[string]*diff.FileDiff{}
+	for _, fd := range fileDiffs {
+		diffsByName[fd.OrigName] = fd
+	}
+
+	if have, want := len(diffsByName), 2; have != want {
+		t.Fatalf("wrong number of diffsByName. want=%d, have=%d", want, have)
+	}
+
+	if _, ok := diffsByName["main.go"]; !ok {
+		t.Errorf("main.go was not changed")
+	}
+	if _, ok := diffsByName["README.md"]; !ok {
+		t.Errorf("README.md was not changed")
+	}
+}
+
+func addToPath(t *testing.T, relPath string) {
+	t.Helper()
+
+	dummyDockerPath, err := filepath.Abs("testdata/dummydocker")
+	if err != nil {
+		t.Fatal(err)
+	}
+	os.Setenv("PATH", fmt.Sprintf("%s%c%s", dummyDockerPath, os.PathListSeparator, os.Getenv("PATH")))
+}
+
+func newZipHandler(t *testing.T, repo, branch string, files map[string]string) http.HandlerFunc {
+	wantPath := fmt.Sprintf("/%s@%s/-/raw", repo, branch)
+
+	downloadName := filepath.Base(repo)
+	mediaType := mime.FormatMediaType("Attachment", map[string]string{
+		"filename": downloadName,
+	})
+
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != wantPath {
+			t.Errorf("request has wrong path. want=%q, have=%q", wantPath, r.URL.Path)
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+
+		w.Header().Set("X-Content-Type-Options", "nosniff")
+		w.Header().Set("Content-Type", "application/zip")
+		w.Header().Set("Content-Disposition", mediaType)
+
+		zipWriter := zip.NewWriter(w)
+
+		for name, body := range files {
+			f, err := zipWriter.Create(name)
+			if err != nil {
+				log.Fatal(err)
+			}
+			if _, err := f.Write([]byte(body)); err != nil {
+				t.Errorf("failed to write body for %s to zip: %s", name, err)
+			}
+		}
+
+		if err := zipWriter.Close(); err != nil {
+			t.Fatalf("closing zipWriter failed: %s", err)
+		}
+	}
+}

internal/campaigns/graphql/repository.go

@@ -19,15 +19,17 @@ fragment repositoryFields on Repository {
 }
 `
 
+type Branch struct {
+	Name   string
+	Target struct{ OID string }
+}
+
 type Repository struct {
 	ID                 string
 	Name               string
 	URL                string
 	ExternalRepository struct{ ServiceType string }
-	DefaultBranch      *struct {
-		Name   string
-		Target struct{ OID string }
-	}
+	DefaultBranch      *Branch
 }
 
 func (r *Repository) BaseRef() string {

internal/campaigns/run_steps.go

@@ -135,8 +135,8 @@ func runSteps(ctx context.Context, wc *WorkspaceCreator, repo *graphql.Repositor
 				Stderr:      strings.TrimSpace(stderrBuffer.String()),
 			}
 		}
-		logger.Logf("[Step %d] complete in %s", i+1, elapsed)
 
+		logger.Logf("[Step %d] complete in %s", i+1, elapsed)
 	}
 
 	if _, err := runGitCmd("add", "--all"); err != nil {

internal/campaigns/testdata/dummydocker/docker

@@ -0,0 +1,52 @@
+#!/bin/bash
+
+# This script is used by the executor integration test to simulate Docker.
+# It gets put into $PATH as "docker" and accepts the "run" command.
+
+# Depending on the arguments to the "run" command it either acts like it
+# created a tempfile, or it executes the script supplied as the last arg to
+# "run".
+
+dummy_temp_file="DUMMYDOCKER-TEMP-FILE"
+
+if [[ "${1}" == "run" ]]; then
+    last_arg="${@: -1}"
+
+    case "$last_arg" in
+      "mktemp")
+        # If the last arg is "mktemp" we're probing for a shell image and
+        # want to create a temp file in the container which we can put a script.
+        echo "${dummy_temp_file}"
+        exit 0
+        ;;
+
+      "${dummy_temp_file}")
+        # If the last arg is the temp file we "created" earlier, we now want to
+        # execute it.
+        #
+        # But the real script is in the matching host temp file, which should
+        # be mounted into the temp file inside the container.
+        #
+        # We need to find it in the args and then execute it.
+
+        host_temp_file=""
+        for i in "$@";
+        do
+          if [[ ${i} =~ ^type=bind,source=(.*),target=${dummy_temp_file},ro$ ]]; then
+            host_temp_file="${BASH_REMATCH[1]}"
+          fi
+        done
+        [ -z "$host_temp_file" ] && echo "host temp file not found in args" && exit 1;
+
+        # Now that we have the path to the host temp file, we can execute it
+        exec bash ${host_temp_file}
+        ;;
+      *)
+        echo "dummydocker doesn't know about this command: $last_arg"
+        exit 1
+        ;;
+    esac
+fi
+
+echo "dummydocker doesn't know about this command: $1"
+exit 1