# Open in Coder

You can embed an "Open in Coder" button into your git repos or internal wikis to
let developers quickly launch a new workspace.

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## How it works

To support any infrastructure and software stack, Coder provides a generic
approach for "Open in Coder" flows.

### 1. Set up git authentication

See [External Authentication](https://coder.com/docs/admin/external-auth.md) to set up Git authentication
in your Coder deployment.

### 2. Modify your template to auto-clone repos

The id in the template's `coder_external_auth` data source must match the
`CODER_EXTERNAL_AUTH_X_ID` in the Coder deployment configuration.

If you want the template to clone a specific git repo:

```hcl
# Require external authentication to use this template
data "coder_external_auth" "github" {
    id = "primary-github"
}

resource "coder_agent" "dev" {
    # ...
    dir = "~/coder"
    startup_script =<<EOF

    # Clone repo from GitHub
    if [ ! -d "coder" ]
    then
        git clone https://github.com/coder/coder
    fi

    EOF
}
```

> [!NOTE]
> The `dir` attribute can be set in multiple ways, for example:
>
> - `~/coder`
> - `/home/coder/coder`
> - `coder` (relative to the home directory)

If you want the template to support any repository via
[parameters](https://coder.com/docs/admin/templates/extending-templates/parameters.md)

```hcl
# Require external authentication to use this template
data "coder_external_auth" "github" {
    id = "primary-github"
}

# Prompt the user for the git repo URL
data "coder_parameter" "git_repo" {
    name          = "git_repo"
    display_name  = "Git repository"
    default       = "https://github.com/coder/coder"
}

locals {
    folder_name = try(element(split("/", data.coder_parameter.git_repo.value), length(split("/", data.coder_parameter.git_repo.value)) - 1), "")
}

resource "coder_agent" "dev" {
    # ...
    dir = "~/${local.folder_name}"
    startup_script =<<EOF

    # Clone repo from GitHub
    if [ ! -d "${local.folder_name}" ]
    then
        git clone ${data.coder_parameter.git_repo.value}
    fi

    EOF
}
```

### 3. Embed the "Open in Coder" button with Markdown

```md
[![Open in Coder](https://YOUR_ACCESS_URL/open-in-coder.svg)](https://YOUR_ACCESS_URL/templates/YOUR_TEMPLATE/workspace)
```

Be sure to replace `YOUR_ACCESS_URL` with your Coder access url (e.g.
<https://coder.example.com>) and `YOUR_TEMPLATE` with the name of your template.

### 4. Optional: pre-fill parameter values in the "Create Workspace" page

This can be used to pre-fill the git repo URL, disk size, image, etc.

```md
[![Open in Coder](https://YOUR_ACCESS_URL/open-in-coder.svg)](https://YOUR_ACCESS_URL/templates/YOUR_TEMPLATE/workspace?param.git_repo=https://github.com/coder/slog&param.home_disk_size%20%28GB%29=20)
```

![Pre-filled parameters](https://raw.githubusercontent.com/coder/coder/main/docs/images/templates/pre-filled-parameters.png)

### 5. Optional: disable specific parameter fields by including their names as

specified in your template in the `disable_params` search params list

```md
[![Open in Coder](https://YOUR_ACCESS_URL/open-in-coder.svg)](https://YOUR_ACCESS_URL/templates/YOUR_TEMPLATE/workspace?disable_params=first_parameter,second_parameter)
```

### Security: consent dialog for automatic creation

When using `mode=auto` with prefilled `param.*` values, Coder displays a
security consent dialog before creating the workspace. This protects users
from malicious links that could provision workspaces with untrusted
configurations, such as dotfiles or startup scripts from unknown sources.

The dialog shows:

- A warning that a workspace is about to be created automatically from a link
- All prefilled `param.*` values from the URL
- **Confirm and Create** and **Cancel** buttons

The workspace is only created if the user explicitly clicks **Confirm and
Create**. Clicking **Cancel** falls back to the standard creation form where
all parameters can be reviewed manually.

![Consent dialog for automatic workspace creation](https://raw.githubusercontent.com/coder/coder/main/docs/images/templates/auto-create-consent-dialog.png)

### Example: Kubernetes

For a full example of the Open in Coder flow in Kubernetes, check out
[this example template](https://github.com/bpmct/coder-templates/tree/main/kubernetes-open-in-coder).