AWS OpsWorks
User Guide (API Version 2013-02-18)

Step 12: Update the Cookbook to Use Custom JSON

Update your cookbook by adding a recipe that references custom JSON that is stored on the instance.

You can specify information in custom JSON format whenever you create, update, or clone a stack or when you run a deployment or stack command. This is useful, for example, for making a small, unchanging portion of data available to your recipes on the instance instead of getting this data from a database. For more information, see Using Custom JSON.

For this walkthrough, you will use custom JSON to provide some fictitious information about a customer invoice. The custom JSON is described later in this step.

To update the cookbook on the instance and run the new recipe

  1. On your local workstation, in the recipes subdirectory in the opsworks_cookbook_demo directory, create a file named custom_json.rb that contains the following recipe code:"********** For customer '#{node['customer-id']}' invoice '#{node['invoice-number']}' **********")"********** Invoice line number 1 is a '#{node['line-items']['line-1']}' **********")"********** Invoice line number 2 is a '#{node['line-items']['line-2']}' **********")"********** Invoice line number 3 is a '#{node['line-items']['line-3']}' **********")

    This recipe displays messages in the log about values in the custom JSON.

  2. At the terminal or command prompt, use the tar command create a new version of the opsworks_cookbook_demo.tar.gz file, which contains the opsworks_cookbook_demo directory and its updated contents.

  3. Upload the updated opsworks_cookbook_demo.tar.gz file to your S3 bucket.

  4. Follow the procedures in Step 5: Update the Cookbook on the Instance and Run the Recipe to update the cookbook on the instance and to run the recipe. In the "To run the recipe" procedure, for Recipes to execute, type opsworks_cookbook_demo::custom_json. For Advanced, Custom Chef JSON, type the following custom JSON:

    { "customer-id": "0123", "invoice-number": "9876", "line-items": { "line-1": "tractor", "line-2": "passenger car", "line-3": "trailer" } }

To test the recipe

  1. With the Running command execute_recipes page displayed from the previous procedures, for cookbooks-demo1, for Log, choose show. The execute_recipes log page is displayed.

  2. Scroll down through the log to find entries that look similar to the following:

    [2015-11-14T14:18:30+00:00] INFO: ********** For customer '0123' invoice '9876' ********** [2015-11-14T14:18:30+00:00] INFO: ********** Invoice line number 1 is a 'tractor' ********** [2015-11-14T14:18:30+00:00] INFO: ********** Invoice line number 2 is a 'passenger car' ********** [2015-11-14T14:18:30+00:00] INFO: ********** Invoice line number 3 is a 'trailer' **********

    These entries display information from the custom JSON that was typed in the Advanced, Custom Chef JSON box.

In the next step, you will update the cookbook to get information from data bags, which are collections of stack settings that AWS OpsWorks Stacks stores on each instance.