With a OneCloud Workspace setup and connections in place, let's create a Chain.
Step 1: Create a Chain
From the OneCloud Workspaces, select the "DEV" Environment.
Add a new Chain by selecting the green (+) button.
Name the Chain "Simple Extract Chain".
Add a Chain Variable by selecting the blue (+)
Set the variable name to "base-url" with the value:
https://s3.amazonaws.com/onecloud-demo
Near the top of the window, click the message icon ✉️ to add an email Notification.
📓 Integrated account platforms will be visible.
Select the desired method of contact. For this example, choose "Email".
Set the condition as "Success".
Add recipients by selecting from the drop-down list.
📓 Only recipients who have access to the chain can be added.
Save the Chain.
As there is no Command, the Chain is invalid.

Step 2: Add a Command to Retrieve Data
Add the first Command and select HTTP ➡️ GET operation.
💡 Use the Find tool to search for "HTTP" and then search for "GET".Add the Command GET by dragging on to the pallet.
Select the new Command and drag it to the Start. The Chain Start will show a plus icon indicating that you can use that command as the start of the Chain.
Edit the Command by double-clicking it.
Name the Command "Get Data".
Set the URL parameter:
- From the left-side panel, under "Select a Variable", choose Chain, “base-url”.
- Then, click back in the URL parameter box- Add the slash character “/” to separate the variables
- Repeat the steps above to add the WORKSPACE Variable “data-type”.
- Finally, type “SAMPLE_DAT.csv” to add the sample file.
⚠️ The filename and letter case must match exactly.Save the Command.

📓 String Concatenation
To concatenate strings in a OneCloud field, be sure to have the field selected and simply add the characters or variables as required.
Step 3: Add a Command to Preview Data
Add a second command to the Chain.
Select the File Utilities ➡️ List File Content Command.
💡 Use the Find tool to search for "File Utilities" and "List File Content".Connect the "Get Data" Command to the "List File Content" Command.
Edit the "List File Content" Command.
Name the Command: "Preview Data".
Scroll down to the "File Name" parameter.
From the left-side panel, choose "Get Data".
Then click "Response" to set the file name to "Response" from the Retrieve Data Command Output.
In the "Preview Lines" parameter below, set the value to "10".
Save the Command.

Step 4: Publish and Run the Chain
Before the Chain can be run, it needs to be Published.
Near the upper-right corner, click the "Publish" button.
A pop-up window opens. No comment is necessary. Click "Publish".
Near the upper-right corner, click the "Execute" button.
Near the upper-right corner, click the "Run Chain" button.
To review the output of the final command, double-click on the "Preview Data" Command and then select the "LOGS" tab to confirm the changes.

📚 Additional topics covered in this article:
Chain Variables
Chain Management
File Utilities Command References - List File Content