feat(git-clone): add pre_clone_script parameter (#887)

## Summary

Add `pre_clone_script` parameter to the git-clone module, allowing users
to run custom scripts before cloning a repository.

## Use Case

This solves SSH host key verification issues (e.g., "Host key
verification failed") by enabling users to configure SSH settings before
the clone operation, such as adding known hosts or setting
`StrictHostKeyChecking no`.

```tf
module "git-clone" {
  count            = data.coder_workspace.me.start_count
  source           = "registry.coder.com/coder/git-clone/coder"
  version          = "1.3.0"
  agent_id         = coder_agent.example.id
  url              = "git@github.com:org/repo.git"
  pre_clone_script = <<-EOT
    #!/bin/bash
    mkdir -p ~/.ssh
    echo -e "Host github.com\n    StrictHostKeyChecking no\n" > ~/.ssh/config
    chmod 600 ~/.ssh/config
  EOT
}
```

Ref:
https://discord.com/channels/747933592273027093/1447777180695396452/1447777180695396452

## Type of Change

- [ ] New module
- [ ] New template
- [ ] Bug fix
- [x] Feature/enhancement
- [ ] Documentation
- [ ] Other

## Module Information

**Path:** `registry/coder/modules/git-clone`  
**New version:** `v1.3.0`  
**Breaking change:** [ ] Yes [x] No

## Testing & Validation

- [x] Tests pass (`bun test`)
- [x] Code formatted (`bun fmt`)
- [x] Changes tested locally

Co-authored-by: DevCats <christofer@coder.com>

registry/coder/modules/git-clone/README.md

@@ -14,7 +14,7 @@ This module allows you to automatically clone a repository by URL and skip if it
 module "git-clone" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/git-clone/coder"
-  version  = "1.2.3"
+  version  = "1.3.0"
   agent_id = coder_agent.example.id
   url      = "https://github.com/coder/coder"
 }
@@ -28,7 +28,7 @@ module "git-clone" {
 module "git-clone" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/git-clone/coder"
-  version  = "1.2.3"
+  version  = "1.3.0"
   agent_id = coder_agent.example.id
   url      = "https://github.com/coder/coder"
   base_dir = "~/projects/coder"
@@ -43,7 +43,7 @@ To use with [Git Authentication](https://coder.com/docs/v2/latest/admin/git-prov
 module "git-clone" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/git-clone/coder"
-  version  = "1.2.3"
+  version  = "1.3.0"
   agent_id = coder_agent.example.id
   url      = "https://github.com/coder/coder"
 }
@@ -70,7 +70,7 @@ data "coder_parameter" "git_repo" {
 module "git_clone" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/git-clone/coder"
-  version  = "1.2.3"
+  version  = "1.3.0"
   agent_id = coder_agent.example.id
   url      = data.coder_parameter.git_repo.value
 }
@@ -105,7 +105,7 @@ Configuring `git-clone` for a self-hosted GitHub Enterprise Server running at `g
 module "git-clone" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/git-clone/coder"
-  version  = "1.2.3"
+  version  = "1.3.0"
   agent_id = coder_agent.example.id
   url      = "https://github.example.com/coder/coder/tree/feat/example"
   git_providers = {
@@ -125,7 +125,7 @@ To GitLab clone with a specific branch like `feat/example`
 module "git-clone" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/git-clone/coder"
-  version  = "1.2.3"
+  version  = "1.3.0"
   agent_id = coder_agent.example.id
   url      = "https://gitlab.com/coder/coder/-/tree/feat/example"
 }
@@ -137,7 +137,7 @@ Configuring `git-clone` for a self-hosted GitLab running at `gitlab.example.com`
 module "git-clone" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/git-clone/coder"
-  version  = "1.2.3"
+  version  = "1.3.0"
   agent_id = coder_agent.example.id
   url      = "https://gitlab.example.com/coder/coder/-/tree/feat/example"
   git_providers = {
@@ -159,7 +159,7 @@ For example, to clone the `feat/example` branch:
 module "git-clone" {
   count       = data.coder_workspace.me.start_count
   source      = "registry.coder.com/coder/git-clone/coder"
-  version     = "1.2.3"
+  version     = "1.3.0"
   agent_id    = coder_agent.example.id
   url         = "https://github.com/coder/coder"
   branch_name = "feat/example"
@@ -177,7 +177,7 @@ For example, this will clone into the `~/projects/coder/coder-dev` folder:
 module "git-clone" {
   count       = data.coder_workspace.me.start_count
   source      = "registry.coder.com/coder/git-clone/coder"
-  version     = "1.2.3"
+  version     = "1.3.0"
   agent_id    = coder_agent.example.id
   url         = "https://github.com/coder/coder"
   folder_name = "coder-dev"
@@ -196,13 +196,36 @@ If not defined, the default, `0`, performs a full clone.
 module "git-clone" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/git-clone/coder"
-  version  = "1.2.3"
+  version  = "1.3.0"
   agent_id = coder_agent.example.id
   url      = "https://github.com/coder/coder"
   depth    = 1
 }
 ```
 
+## Pre-clone script
+
+Run a custom script before cloning the repository by setting the `pre_clone_script` variable.
+This is useful for preparing the environment or validating prerequisites before cloning.
+
+```tf
+module "git-clone" {
+  count            = data.coder_workspace.me.start_count
+  source           = "registry.coder.com/coder/git-clone/coder"
+  version          = "1.3.0"
+  agent_id         = coder_agent.example.id
+  url              = "https://github.com/coder/coder"
+  pre_clone_script = <<-EOT
+    #!/bin/bash
+    echo "Preparing to clone repository..."
+    # Check prerequisites
+    command -v npm >/dev/null 2>&1 || { echo "npm is required but not installed."; exit 1; }
+    # Set up environment
+    export NODE_ENV=development
+  EOT
+}
+```
+
 ## Post-clone script
 
 Run a custom script after cloning the repository by setting the `post_clone_script` variable.
@@ -212,7 +235,7 @@ This is useful for running initialization tasks like installing dependencies or
 module "git-clone" {
   count             = data.coder_workspace.me.start_count
   source            = "registry.coder.com/coder/git-clone/coder"
-  version           = "1.2.3"
+  version           = "1.3.0"
   agent_id          = coder_agent.example.id
   url               = "https://github.com/coder/coder"
   post_clone_script = <<-EOT

registry/coder/modules/git-clone/main.test.ts

@@ -261,4 +261,16 @@ describe("git-clone", async () => {
     expect(output.stdout).toContain("Running post-clone script...");
     expect(output.stdout).toContain("Post-clone script executed");
   });
+
+  it("runs pre-clone script", async () => {
+    const state = await runTerraformApply(import.meta.dir, {
+      agent_id: "foo",
+      url: "fake-url",
+      pre_clone_script: "echo 'Pre-clone script executed'",
+    });
+    const output = await executeScriptInContainer(state, "alpine/git");
+    expect(output.stdout).toContain("Running pre-clone script...");
+    expect(output.stdout).toContain("Pre-clone script executed");
+    expect(output.stdout).toContain("Cloning fake-url to ~/fake-url...");
+  });
 });

registry/coder/modules/git-clone/main.tf

@@ -68,6 +68,12 @@ variable "post_clone_script" {
   default     = null
 }
 
+variable "pre_clone_script" {
+  description = "Custom script to run before cloning the repository. Runs before git clone, even if the repository already exists."
+  type        = string
+  default     = null
+}
+
 locals {
   # Remove query parameters and fragments from the URL
   url = replace(replace(var.url, "/\\?.*/", ""), "/#.*/", "")
@@ -89,6 +95,8 @@ locals {
   web_url = startswith(local.clone_url, "git@") ? replace(replace(local.clone_url, ":", "/"), "git@", "https://") : local.clone_url
   # Encode the post_clone_script for passing to the shell script
   encoded_post_clone_script = var.post_clone_script != null ? base64encode(var.post_clone_script) : ""
+  # Encode the pre_clone_script for passing to the shell script
+  encoded_pre_clone_script = var.pre_clone_script != null ? base64encode(var.pre_clone_script) : ""
 }
 
 output "repo_dir" {
@@ -129,6 +137,7 @@ resource "coder_script" "git_clone" {
     BRANCH_NAME : local.branch_name,
     DEPTH = var.depth,
     POST_CLONE_SCRIPT : local.encoded_post_clone_script,
+    PRE_CLONE_SCRIPT : local.encoded_pre_clone_script,
   })
   display_name       = "Git Clone"
   icon               = "/icon/git.svg"

registry/coder/modules/git-clone/run.sh

@@ -7,6 +7,7 @@ BRANCH_NAME="${BRANCH_NAME}"
 CLONE_PATH="$${CLONE_PATH/#\~/$${HOME}}"
 DEPTH="${DEPTH}"
 POST_CLONE_SCRIPT="${POST_CLONE_SCRIPT}"
+PRE_CLONE_SCRIPT="${PRE_CLONE_SCRIPT}"
 
 # Check if the variable is empty...
 if [ -z "$REPO_URL" ]; then
@@ -33,6 +34,16 @@ if [ ! -d "$CLONE_PATH" ]; then
   mkdir -p "$CLONE_PATH"
 fi
 
+# Run pre-clone script if provided
+if [ -n "$PRE_CLONE_SCRIPT" ]; then
+  echo "Running pre-clone script..."
+  PRE_CLONE_TMP=$(mktemp)
+  echo "$PRE_CLONE_SCRIPT" | base64 -d > "$PRE_CLONE_TMP"
+  chmod +x "$PRE_CLONE_TMP"
+  $PRE_CLONE_TMP
+  rm "$PRE_CLONE_TMP"
+fi
+
 # Check if the directory is empty
 # and if it is, clone the repo, otherwise skip cloning
 if [ -z "$(ls -A "$CLONE_PATH")" ]; then