Plumbing

The set of tools that helps instantiates HTTP services built from pipeline of command line scripts. This is meant to be a dirty quick way to have bunch of small services up and running in no time.

The key difference from other minimalistic "frameworks" - no dependencies on 3rd party or assumed IT infrastructure. Just have it up and running for proof of concept demo. Security is not in a scope of concerns. Prove that the demo works - this is begin and end of our scope. Be aware!

Rationality

I am tired fixing Python scripts that has tons of ever changing dependencies.

I do not have luxury of time to spend on IT services every time I need to kick small demo.

My main prototype platform is Linux headless servers. No promises for Windows. The exit_status is string; "ok" for return code 0 or error description otherwise.

Use Cases

1. a call triggers comand on the server

synchronous flow
+--------+ 1. GET /cmd1/p1  +---------------+
|        +----------------> |               |
| Client |                  | Server        |
|        |  3. exit_status  |  ~/piped    |
|        | <----------------+   2. $cmd1 p1 |
+---------                  +---------------+

2. comand started by scheduler waits for trigger file before proceed.

Example of waiting for trigger file checking file existence every 10 seconds for 6 times with 60 seconds timeout total.

$ wait4file -w 10 -n 6 //share/trigger.file || exit 1

Installation

Simply build project with Go tool on your platform. Tested with GO 1.11.

mkdir prj; cd prj
export  GOPATH=`pwd`
go get github.com/smile-on/plumbing/cmd/wait4file
# or
go get -v github.com/smile-on/plumbing/cmd/piped

How To Run

wait4file

$ wait4file -w 10 -n 6 //share/trigger.file && echo "got file" || echo "no file"
piped

Create ini file for your service. An example of serviceTouch.ini:

[/touch/{p1}]
touch {{.p1}}

Now you can use piped executable with your configuration.

piped -ini serviceTouch.ini -listen :8080

Note, you may use piped binary on any computer of that platform just by copying one binary file and creating configuration file. Pipe daemon does not have any dependencies beside standard GO runtime requirements.

Enjoy!