run README build and deploy commands through bash shell (fix #21)

README.md

@@ -33,28 +33,31 @@ If you'd like, make sure to include the following comment code tag in your READM
 build and deploy your sample:
 
 ```text
-[//]: # ({sst-run-unix})
+[//]: # ({sst-run-bash})
 ```
 
 For example:
 ````text
-[//]: # ({sst-run-unix})
+[//]: # ({sst-run-bash})
 ```
 gcloud builds submit --tag=gcr.io/${GOOGLE_CLOUD_PROJECT}/run-mysql
 ```
 ````
 
 When parsing the README for custom build and deploy commands, the serverless sample tester will include any commands
-inside a code fence that is immediately preceded by a line containing `{sst-run-unix}`. You can use Markdown syntax
-(e.g. `[//]: # ({sst-run-unix})`) to include this line without making it visible when rendered.
+inside a code fence that is immediately preceded by a line containing `{sst-run-bash}`. You can use Markdown syntax
+(e.g. `[//]: # ({sst-run-bash})`) to include this line without making it visible when rendered.
 
-The parsed commands will not be run through a shell, meaning that the program will not perform any expansions,
-pipelines, redirections or any other functions that shells are responsible for. This also means that popular shell
-builtin commands like `cd`, `export`, and `echo` will not be available or may not work as expected.  
+The parsed commands will be run through the Bash shell, but each command will be run through a separate instance
+of the shell, meaning that commands such as `cd` or `export` may not work as expected. All commands will be run in the
+sample's root directory.
 
-However, any environment variables referenced in the form of `$var` or `${var}` will expanded. In addition, bash-style
-multiline commands (i.e. non-quoted backslashes at the end of a line that indicate a line continuation) will also be 
-supported. 
+However, any environment variables referenced in the form of `$var` or `${var}` will expanded. Each command's process
+will share the same environment as the process you execute `sst` from. So environment variables you set in your shell
+before calling `sst` will be available for the commands you specify in your README. 
+
+In addition, bash-style multiline commands (i.e. non-quoted backslashes at the end of a line that indicate a line
+continuation) will also be supported.
 
 Do not set the Cloud Run region you'd like to deploy to through the `--region` flag in the `gcloud run` commands.
 Instead, as mentioned above, do so by setting the `run/region` gcloud property.

internal/cmd/cmd.go

@@ -20,6 +20,7 @@ import (
 	"github.com/GoogleCloudPlatform/serverless-sample-tester/internal/util"
 	"github.com/spf13/cobra"
 	"log"
+	"os"
 	"os/exec"
 	"path/filepath"
 )
@@ -52,8 +53,9 @@ func Root(cmd *cobra.Command, args []string) error {
 	log.Println("Getting identity token for gcloud auhtorized account")
 	var identToken string
 
-	a := append(util.GcloudCommonFlags, "auth", "print-identity-token")
-	identToken, err = util.ExecCommand(exec.Command("gcloud", a...), s.Dir)
+	c := exec.Command("gcloud", "auth", "print-identity-token")
+	c.Env = append(os.Environ(), util.GcloudCommonEnv...)
+	identToken, err = util.ExecCommand(c, s.Dir)
 
 	if err != nil {
 		return fmt.Errorf("[cmd.Root] getting identity token for gcloud auhtorized account: %w", err)

internal/gcloud/cloud_run_service.go

@@ -19,6 +19,7 @@ import (
 	"encoding/hex"
 	"fmt"
 	"github.com/GoogleCloudPlatform/serverless-sample-tester/internal/util"
+	"os"
 	"os/exec"
 	"strings"
 	"unicode"
@@ -37,8 +38,9 @@ type CloudRunService struct {
 
 // Delete calls the external gcloud SDK and deletes the Cloud Run Service associated with the current cloudRunService.
 func (s CloudRunService) Delete(sampleDir string) error {
-	a := append(util.GcloudCommonFlags, "run", "services", "delete", s.Name, "--platform=managed")
-	_, err := util.ExecCommand(exec.Command("gcloud", a...), sampleDir)
+	c := exec.Command("gcloud", "run", "services", "delete", s.Name, "--platform=managed")
+	c.Env = append(os.Environ(), util.GcloudCommonEnv...)
+	_, err := util.ExecCommand(c, sampleDir)
 
 	if err != nil {
 		return fmt.Errorf("[CloudRunService.delete] deleting Cloud Run Service: %w", err)
@@ -54,9 +56,9 @@ func (s *CloudRunService) URL(sampleDir string) (string, error) {
 		return s.url, nil
 	}
 
-	a := append(util.GcloudCommonFlags, "run", "--platform=managed", "services", "describe", s.Name,
-		"--format=value(status.url)")
-	url, err := util.ExecCommand(exec.Command("gcloud", a...), sampleDir)
+	c := exec.Command("gcloud", "run", "--platform=managed", "services", "describe", s.Name, "--format=value(status.url)")
+	c.Env = append(os.Environ(), util.GcloudCommonEnv...)
+	url, err := util.ExecCommand(c, sampleDir)
 
 	if err != nil {
 		return "", fmt.Errorf("[CloudRunService.URL] getting Cloud Run Service URL: %w", err)

internal/lifecycle/lifecycle.go

@@ -87,14 +87,13 @@ func NewLifecycle(sampleDir, serviceName, gcrURL string) (Lifecycle, error) {
 // project. It uses `gcloud builds submit` for building the samples container image and submitting it to the container
 // and `gcloud run deploy` for deploying it to Cloud Run.
 func buildDefaultLifecycle(serviceName, gcrURL string) Lifecycle {
-	a0 := append(util.GcloudCommonFlags, "builds", "submit", fmt.Sprintf("--tag=%s", gcrURL))
-	a1 := append(util.GcloudCommonFlags, "run", "deploy", serviceName, fmt.Sprintf("--image=%s", gcrURL),
-		"--platform=managed")
+	c0 := exec.Command("gcloud", "builds", "submit", fmt.Sprintf("--tag=%s", gcrURL))
+	c0.Env = append(os.Environ(), util.GcloudCommonEnv...)
 
-	return Lifecycle{
-		exec.Command("gcloud", a0...),
-		exec.Command("gcloud", a1...),
-	}
+	c1 := exec.Command("gcloud", "run", "deploy", serviceName, fmt.Sprintf("--image=%s", gcrURL), "--platform=managed")
+	c1.Env = append(os.Environ(), util.GcloudCommonEnv...)
+
+	return Lifecycle{c0, c1}
 }
 
 // buildDefaultJavaLifecycle builds a build and deploy command lifecycle with reasonable defaults for Java

internal/lifecycle/readme.go

@@ -27,7 +27,7 @@ import (
 const (
 	// The tag that should appear immediately before code blocks in a README to indicate that the enclosed commands
 	// are to be used by this program for building and deploying the sample.
-	codeTag = "{sst-run-unix}"
+	codeTag = "{sst-run-bash}"
 
 	// A non-quoted backslash in bash at the end of a line indicates a line continuation from the current line to the
 	// next line.
@@ -49,9 +49,9 @@ var (
 // terminal commands inside of a Markdown code block.
 type codeBlock []string
 
-// toCommands extracts the terminal commands contained within the current codeBlock. It handles the expansion of
-// environment variables and line continuations. It also detects Cloud Run service names Google Container Registry
-// container image URLs and replaces them with the ones provided.
+// toCommands extracts the terminal commands contained within the current codeBlock and creates `exec.Cmd`s for them
+// that pass them through the Bash shell. It also detects Cloud Run service names Google Container Registry container
+// image URLs and replaces them with the ones provided.
 func (cb codeBlock) toCommands(serviceName, gcrURL string) ([]*exec.Cmd, error) {
 	var cmds []*exec.Cmd
 
@@ -79,17 +79,12 @@ func (cb codeBlock) toCommands(serviceName, gcrURL string) ([]*exec.Cmd, error)
 			line = line + l
 		}
 
-		line = os.ExpandEnv(line)
 		line = gcrURLRegexp.ReplaceAllString(line, gcrURL)
 		line = replaceServiceName(line, serviceName)
-		sp := strings.Split(line, " ")
-
-		var cmd *exec.Cmd
-		if sp[0] == "gcloud" {
-			a := append(util.GcloudCommonFlags, sp[1:]...)
-			cmd = exec.Command("gcloud", a...)
-		} else {
-			cmd = exec.Command(sp[0], sp[1:]...)
+
+		cmd := exec.Command("bash", "-c", line)
+		if gcloudCommandRegexp.MatchString(line) {
+			cmd.Env = append(os.Environ(), util.GcloudCommonEnv...)
 		}
 
 		cmds = append(cmds, cmd)

internal/sample/sample.go

@@ -19,6 +19,7 @@ import (
 	"github.com/GoogleCloudPlatform/serverless-sample-tester/internal/gcloud"
 	"github.com/GoogleCloudPlatform/serverless-sample-tester/internal/lifecycle"
 	"github.com/GoogleCloudPlatform/serverless-sample-tester/internal/util"
+	"os"
 	"os/exec"
 	"strings"
 	"unicode"
@@ -52,8 +53,9 @@ func NewSample(dir string) (*Sample, error) {
 		return nil, fmt.Errorf("[sample.NewSample] generating Container Registry container image tag: %w", err)
 	}
 
-	a := append(util.GcloudCommonFlags, "config", "get-value", "core/project")
-	projectID, err := util.ExecCommand(exec.Command("gcloud", a...), dir)
+	c := exec.Command("gcloud", "config", "get-value", "core/project")
+	c.Env = append(os.Environ(), util.GcloudCommonEnv...)
+	projectID, err := util.ExecCommand(c, dir)
 
 	if err != nil {
 		return nil, fmt.Errorf("[sample.NewSample] getting gcloud default project: %w", err)
@@ -91,8 +93,9 @@ func sampleName(dir string) string {
 
 // DeleteCloudContainerImage deletes the sample's container image off of the Container Registry.
 func (s *Sample) DeleteCloudContainerImage() error {
-	a := append(util.GcloudCommonFlags, "container", "images", "delete", s.cloudContainerImageURL)
-	_, err := util.ExecCommand(exec.Command("gcloud", a...), s.Dir)
+	c := exec.Command("container", "images", "delete", s.cloudContainerImageURL)
+	c.Env = append(os.Environ(), util.GcloudCommonEnv...)
+	_, err := util.ExecCommand(c, s.Dir)
 
 	if err != nil {
 		return fmt.Errorf("[Sample.DeleteCloudContainerImage] deleting Container Registry container image: %w", err)

internal/util/command.go

@@ -23,10 +23,10 @@ import (
 	"strings"
 )
 
-// GcloudCommonFlags is a slice of common flags that should be added as arguments to all executions of the external
-// gcloud command.
-var GcloudCommonFlags = []string{
-	"--quiet",
+// GcloudCommonEnv is a slice of common environment variables that should be added to the environment of all executions
+// of the external gcloud command.
+var GcloudCommonEnv = []string{
+	"CLOUDSDK_CORE_DISABLE_PROMPTS=TRUE",
 }
 
 // ExecCommand executes an exec.Cmd. If the command exits successfully, its stdout will be returned. If there's an