1. Executing Host Commands
MIS 3406
Department of MIS
Fox School of Business
Temple University

2. Why Execute Host Commands
Why would you want to execute host commands within code?
Automate repetitive tasks
Moving data
Monitoring systems
Backups
DevOps
Automated operations
Automated testing
Automated migration of code and data Dev  QA  Prod

3. What do you need to be able to do?
Execute a command
Capture and process the output
Stdout –
Stderr –
Capture the “Exit Code” (a.k.a. “Return Code”)
Conditional execution of code based on results of the host command

4. Execute a command at the command line…
Arguments 1, 2 and 3
stdout

5. Let’s execute it within NodeJS…
Setup .spawnSync
stdout
Command
Arguments 1, 2 and 3
stderr
Exit Code

6. How about a bad command…
Setup .spawnSync
stdout
Command
Arguments 1, 2 and 3
stderr
Exit Code

7. OS Command (not a .exe) – Windows Only
Arguments
Need a Shell
stdout
stderr
Exit Code

8. HostCommandWithExe.js
Get your first program running that executes a host command with an exe.

9. HostCommandWithoutExe.js
Get your first program running that executes a host command without an exe.

10. Challenges
MyPing
MyDir
WhoAmI
MyHostName
MyIPAddress
LookupIPAddress