This action dynamically generates Open Graph images (OG:Image) from template files. This is useful for giving your links more context on social media such as Twitter and LinkedIn.

With some CSS finesse, you too can auto-generate your own OG images like GitHub does. So when people posts links to your site, they are informative and look great:

This action uses pandoc to convert the files into an all-in-one webpage and Microsoft Playwright to take a "screenshot" which is a 1200x630 image.

Basically, you create a markdown or html template with phrases to replace like --AUTHOR-- or --TITLE--.

<div class="title">--TITLE--</div>
<div class="author">A new article by --AUTHOR--!</div>

Then let the action know what --AUTHOR-- and --TITLE-- will be replaced by.

@{
    "--TITLE--"     = "New book released!"
    "--AUTHOR--"    = "Chrissy LeMaire"
}

Want to make it pretty? You can even attach a stylesheet or reference an online stylesheet or both.

Keep in mind that the generated image is 1200x630 so your stylesheet or general design should accommodate that size.

To dynamically generate your own image, just copy the code below and modify as desired. I know I just want to see stuff work, so it works without any modifications, right out of the box.

    - name: Generate Open Graph Image
      uses: potatoqualitee/ogimage@v1.0
      with:
        stylesheet: ./sample/style.css

Once that runs, check the Actions tab in your repo, then download the artifact to see your image.

You can also get a lot more advanced too.

    - name: Generate Open Graph Image
      uses: potatoqualitee/ogimage@v1.0
      with:
        template-path: ./blog/assets/template.md
        stylesheet: ./blog/assets/template-style.css, https://fonts.googleapis.com/css?family=Ubuntu
        hashtable: |-
          @{
              "FileName"          = "my-files"
              "--TITLE--"         = "This can be anything"
              "--AUTHOR--"        = "Anyone"
              "--SYNOPSIS--"      = "All of these variable names and replacement values are just made up"
              "--FOOTER--"        = "Copyright 1998"
          }
        output-path: ./gh-pages/images

If you'd like to see it work before diving in, this example works:

      - name: Generate Open Graph Image
        uses: potatoqualitee/ogimage@v1.0
        with:
          stylesheet: ./sample/style.css
          hashtable: |-
            @{
                "FileName"          = "rbar-performance-in-powershell"
                "--TITLE--"         = "RBAR Performance in PowerShell"
                "--AUTHOR--"        = "By Chrissy LeMaire"
                "--SYNOPSIS--"      = "In this article, we'll cover looping performance for PowerShell."
                "--FOOTER--"        = "See more at netnerds.net"
            }

The output is a file named rbar-performance-in-powershell.png which looks like this

I'm not so good at CSS and HTML so it could be better, but this shows you how it can work. Here are the sample files I used.

• /sample/template.md
• /sample/style.css

For multiple images, you will want to specify a hashtable-filename such as ./assets/hash.ps1 that contains code formatted similar to the following:

@(
    @{
        "FileName"         = "MyPic"
        "--TITLE--"        = "Sample Title"
        "--AUTHOR--"       = "Foster Jones"
        "--SYNOPSIS--"     = "This too"
        "--FOOTER--"       = "Footer sample"
    },
    @{
        "FileName"         = "My Second Pic"
        "--TITLE--"        = "Another Title"
        "--AUTHOR--"       = "Adam Pie"
        "--SYNOPSIS--"     = "And this too"
        "--FOOTER--"       = "Another footer sample"
    }
)

Once the file is created and stored in your repo, specify it as a filename

      - name: Generate Open Graph Image
        uses: potatoqualitee/ogimage@v1.0
        with:
          stylesheet: ./sample/style.css
          hashtable-filepath: ./sample/replace-template.ps1

To add it to your website, copy the images to an appropriate directory, edit the html output of your webpage and add the following code in your <head>.

<meta property="og:type" content="article" />
<meta property="og:title" content="dbatools docs:  Add-DbaAgDatabase" />
<meta property="og:url" content="https://docs.dbatools.io/Add-DbaAgDatabase.html" />
<meta property="og:description" content="dbatools docs for Add-DbaAgDatabase" />
<meta property="og:site_name" content="docs.dbatools.io" />
<meta property="og:locale" content="en_US" />
<meta property="og:image" content="https://docs.dbatools.io/assets/thumbs/Add-DbaAgDatabase.png">

<meta name="twitter:title" content="dbatools docs:  Add-DbaAgDatabase">
<meta name="twitter:creator" content="@psdbatools">
<meta name="twitter:site" content="@psdbatools" />
<meta name="twitter:image" content="https://docs.dbatools.io/assets/thumbs/Add-DbaAgDatabase.png">
<meta name="twitter:card" content="summary_large_image"> 

Create a workflow .yml file in your repositories .github/workflows directory. An example workflow is available below. For more information, reference the GitHub Help Documentation for Creating a workflow file.

• template-path - The path to the html or markdown to use as a template.
• stylesheet - A comma-separated list of paths to any CSS files you'll be using. Can include file paths and even web addresses.
• hashtable - A hashtable of key/value pairs to replace in the template. Use a FileName key (without an extension) to specify the filename to use for the image, otherwise, it'll be saved with a temporary name.
• hashtable-filepath - If you'd prefer to use an external PowerShell file to create your images instead of a hardcoded hashtable in YAML, you can use this to specify the filepath to use. This file should only contain a hashtable and start with @{
• output-path - The output path where the generated images will be saved. This will generally be your website's repository. By default, however, it'll save all output to /tmp/pics.
• no-artifact - By default, the markdown, html and png files are saved as an artifact. Set to true to skip the upload.
• no-optimize - Don't optimize the png (greatly decreases size but takes a bit).

The cache is scoped to the key and branch. The default branch cache is available to other branches.

Using pwsh on Ubuntu

on: [push]

jobs:
  run-on-linux:
    runs-on: ubuntu-latest
    steps:
      - uses: potatoqualitee/ogimage@v1.0
      - name: Create OG:Images
        uses: ./

Using powershell on Windows. pwsh also works and is the default.

on: [push]

jobs:
  run-on-linux:
    runs-on: ubuntu-latest
    steps:
      - uses: potatoqualitee/ogimage@v1.0
      - name: Create OG:Images
        uses: ./

      - name: Show that the Action works
        shell: pwsh
        run: |
          Get-ChildItem /tmp/pics | Select-Object FullName

Pull requests are welcome!

The scripts and documentation in this project are released under the MIT License