feat: Add Support for Customising the Shell for Pre and Post Workflow Hooks (runatlantis#3451)

Author: X-Guardian

runatlantis.io/docs/post-workflow-hooks.md

@@ -6,14 +6,12 @@ workflows](custom-workflows.html#custom-run-command) in that they are run
 outside of Atlantis commands. Which means they do not surface their output
 back to the PR as a comment.
 
-Post workflow hooks also only allow `run` and `description` commands.
-
 [[toc]]
 
 ## Usage
 
 Post workflow hooks can only be specified in the Server-Side Repo Config under
-`repos` key.
+the `repos` key.
 
 ## Use Cases
 
@@ -45,6 +43,25 @@ repos:
       # ...
 ```
 
+## Customizing the Shell
+
+By default, the commands will be run using the 'sh' shell with an argument of '-c'. This
+can be customized using the `shell` and `shellArgs` keys.
+
+Example:
+
+```yaml
+repos:
+    - id: /.*/
+      post_workflow_hooks:
+        - run: |
+            echo 'atlantis.yaml config:'
+            cat atlantis.yaml
+          description: atlantis.yaml report
+          shell: bash
+          shellArgs: -cv
+```
+
 ## Reference
 
 ### Custom `run` Command
@@ -60,6 +77,8 @@ command](custom-workflows.html#custom-run-command).
 | ----------- | ------ | ------- | -------- | --------------------- |
 | run         | string | none    | no       | Run a custom command  |
 | description | string | none    | no       | Post hook description |
+| shell       | string | 'sh'    | no       | The shell to use for running the command |
+| shellArgs   | string | '-c'    | no       | The shell arguments to use for running the command |
 
 ::: tip Notes
 * `run` commands are executed with the following environment variables:

runatlantis.io/docs/pre-workflow-hooks.md

@@ -4,27 +4,29 @@ Pre workflow hooks can be defined to run scripts before default or custom
 workflows are executed. Pre workflow hooks differ from [custom
 workflows](custom-workflows.html#custom-run-command) in several ways.
 
-1. Pre workflow hooks do not require for repository configuration to be
+1. Pre workflow hooks do not require the repository configuration to be
    present. This can be utilized to [dynamically generate repo configs](pre-workflow-hooks.html#dynamic-repo-config-generation).
 2. Pre workflow hooks are run outside of Atlantis commands. Which means
    they do not surface their output back to the PR as a comment.
-3. Pre workflow hooks only allow `run` and `description` commands.
 
 [[toc]]
 
 ## Usage
-Pre workflow hooks can only be specified in the Server-Side Repo Config under
-`repos` key. 
+
+Pre workflow hooks can only be specified in the Server-Side Repo Config under the
+`repos` key.
 ::: tip Note
 `pre-workflow-hooks` do not prevent Atlantis from executing its
 workflows(`plan`, `apply`) even if a `run` command exits with an error.
 ::: 
 
 ## Use Cases
+
 ### Dynamic Repo Config Generation
-If you want generate your `atlantis.yaml` before Atlantis can parse it. You
-can add a `run` command to `pre_workflow_hooks`. Your Repo config will be generated
-right before Atlantis can parse it.
+
+To generate the repo `atlantis.yaml` before Atlantis can parse it,
+add a `run` command to `pre_workflow_hooks`. Your Repo config will be generated
+right before Atlantis parses it.
 
 ```yaml
 repos:
@@ -33,17 +35,43 @@ repos:
         - run: ./repo-config-generator.sh
           description: Generating configs
 ```
+
+## Customizing the Shell
+
+By default, the command will be run using the 'sh' shell with an argument of '-c'. This
+can be customized using the `shell` and `shellArgs` keys.
+
+Example:
+
+```yaml
+repos:
+    - id: /.*/
+      pre_workflow_hooks:
+        - run: |
+            echo "generating atlantis.yaml"
+            terragrunt-atlantis-config generate --output atlantis.yaml --autoplan --parallel
+          description: Generating atlantis.yaml
+          shell: bash
+          shellArgs: -cv
+```
+
 ## Reference
+
 ### Custom `run` Command
-This is very similar to [custom workflow run
-command](custom-workflows.html#custom-run-command). 
+
+This is very similar to the [custom workflow run
+command](custom-workflows.html#custom-run-command).
+
 ```yaml
 - run: custom-command
 ```
+
 | Key         | Type   | Default | Required | Description          |
 | ----------- | ------ | ------- | -------- | -------------------- |
 | run         | string | none    | no       | Run a custom command |
 | description | string | none    | no       | Pre hook description |
+| shell       | string | 'sh'    | no       | The shell to use for running the command |
+| shellArgs   | string | '-c'    | no       | The shell arguments to use for running the command |
 
 ::: tip Notes
 * `run` commands are executed with the following environment variables:
@@ -64,4 +92,3 @@ command](custom-workflows.html#custom-run-command).
   * `COMMAND_NAME` - The name of the command that is being executed, i.e. `plan`, `apply` etc.
   * `OUTPUT_STATUS_FILE` - An output file to customize the success or failure status. ex. `echo 'failure' > $OUTPUT_STATUS_FILE`.
 :::
-

server/controllers/events/events_controller_e2e_test.go

@@ -610,9 +610,11 @@ func TestGitHubWorkflow(t *testing.T) {
 
 			expNumHooks := len(c.Comments) + 1 - c.ExpParseFailedCount
 			// Let's verify the pre-workflow hook was called for each comment including the pull request opened event
-			mockPreWorkflowHookRunner.VerifyWasCalled(Times(expNumHooks)).Run(Any[models.WorkflowHookCommandContext](), Eq("some dummy command"), Any[string]())
+			mockPreWorkflowHookRunner.VerifyWasCalled(Times(expNumHooks)).Run(Any[models.WorkflowHookCommandContext](),
+				Eq("some dummy command"), Any[string](), Any[string](), Any[string]())
 			// Let's verify the post-workflow hook was called for each comment including the pull request opened event
-			mockPostWorkflowHookRunner.VerifyWasCalled(Times(expNumHooks)).Run(Any[models.WorkflowHookCommandContext](), Eq("some post dummy command"), Any[string]())
+			mockPostWorkflowHookRunner.VerifyWasCalled(Times(expNumHooks)).Run(Any[models.WorkflowHookCommandContext](),
+				Eq("some post dummy command"), Any[string](), Any[string](), Any[string]())
 
 			// Now we're ready to verify Atlantis made all the comments back (or
 			// replies) that we expect.  We expect each plan to have 1 comment,
@@ -794,7 +796,8 @@ func TestSimpleWorkflow_terraformLockFile(t *testing.T) {
 			}
 
 			// Let's verify the pre-workflow hook was called for each comment including the pull request opened event
-			mockPreWorkflowHookRunner.VerifyWasCalled(Times(2)).Run(Any[models.WorkflowHookCommandContext](), Eq("some dummy command"), Any[string]())
+			mockPreWorkflowHookRunner.VerifyWasCalled(Times(2)).Run(Any[models.WorkflowHookCommandContext](),
+				Eq("some dummy command"), Any[string](), Any[string](), Any[string]())
 
 			// Now we're ready to verify Atlantis made all the comments back (or
 			// replies) that we expect.  We expect each plan to have 1 comment,

server/core/config/raw/workflow_step.go

@@ -76,6 +76,8 @@ func (s WorkflowHook) ToValid() *valid.WorkflowHook {
 			StepName:        RunStepName,
 			RunCommand:      s.StringVal["run"],
 			StepDescription: s.StringVal["description"],
+			Shell:           s.StringVal["shell"],
+			ShellArgs:       s.StringVal["shellArgs"],
 		}
 	}
 

server/core/config/valid/global_cfg.go

@@ -109,6 +109,8 @@ type WorkflowHook struct {
 	StepName        string
 	RunCommand      string
 	StepDescription string
+	Shell           string
+	ShellArgs       string
 }
 
 // DefaultApplyStage is the Atlantis default apply stage.

server/core/runtime/mocks/mock_post_workflows_hook_runner.go

@@ -13,17 +13,18 @@ import (
 
 //go:generate pegomock generate --package mocks -o mocks/mock_post_workflows_hook_runner.go PostWorkflowHookRunner
 type PostWorkflowHookRunner interface {
-	Run(ctx models.WorkflowHookCommandContext, command string, path string) (string, string, error)
+	Run(ctx models.WorkflowHookCommandContext, command string, shell string, shellArgs string, path string) (string, string, error)
 }
 
 type DefaultPostWorkflowHookRunner struct {
 	OutputHandler jobs.ProjectCommandOutputHandler
 }
 
-func (wh DefaultPostWorkflowHookRunner) Run(ctx models.WorkflowHookCommandContext, command string, path string) (string, string, error) {
+func (wh DefaultPostWorkflowHookRunner) Run(ctx models.WorkflowHookCommandContext, command string, shell string, shellArgs string, path string) (string, string, error) {
 	outputFilePath := filepath.Join(path, "OUTPUT_STATUS_FILE")
 
-	cmd := exec.Command("sh", "-c", command) // #nosec
+	shellArgsSlice := append(strings.Split(shellArgs, " "), command)
+	cmd := exec.Command(shell, shellArgsSlice...) // #nosec
 	cmd.Dir = path
 
 	baseEnvVars := os.Environ()
@@ -58,7 +59,7 @@ func (wh DefaultPostWorkflowHookRunner) Run(ctx models.WorkflowHookCommandContex
 	wh.OutputHandler.SendWorkflowHook(ctx, "\n", true)
 
 	if err != nil {
-		err = fmt.Errorf("%s: running %q in %q: \n%s", err, command, path, out)
+		err = fmt.Errorf("%s: running %q in %q: \n%s", err, shell+" "+shellArgs+" "+command, path, out)
 		ctx.Log.Debug("error: %s", err)
 		return string(out), "", err
 	}
@@ -70,12 +71,12 @@ func (wh DefaultPostWorkflowHookRunner) Run(ctx models.WorkflowHookCommandContex
 		var customStatusErr error
 		customStatusOut, customStatusErr = os.ReadFile(outputFilePath)
 		if customStatusErr != nil {
-			err = fmt.Errorf("%s: running %q in %q: \n%s", err, command, path, out)
+			err = fmt.Errorf("%s: running %q in %q: \n%s", err, shell+" "+shellArgs+" "+command, path, out)
 			ctx.Log.Debug("error: %s", err)
 			return string(out), "", err
 		}
 	}
 
-	ctx.Log.Info("successfully ran %q in %q", command, path)
-	return outString, strings.Trim(string(customStatusOut), "\n"), nil
+	ctx.Log.Info("successfully ran %q in %q", shell+" "+shellArgs+" "+command, path)
+	return string(out), strings.Trim(string(customStatusOut), "\n"), nil
 }