procjs

Introduction

This project uses semantic versioning.

This package provides some command-line utilities for inspecting processes' status on a server:

• jsps: wrapper for the ps utility that produces a json array with processes' info. It is based on Mike Grundy's awkward script.

• proc: REST server that polls periodically jsps and exports process information in json format. The following routes are supported:

  • /proc get all jsps output
  • /proc/:key returns the value of key for all processes (in a list)
  • /proc/:key/:value returns a json object for the process that has key=value
  • /proc/:key/:value/:proj as above, but projects the result onto field proj

• eps: simple program that reorders the output of jsps by using fuzzy string matching on command name and user name (if available). To be used by piping the output of jsps.

Installation

Install LiveScript globally:

> npm install LiveScript -g

Then:

> npm install procjs -g

Usage

jsps can be used with all the usual ps options (that depend, in turn, on your OS):

jsps -fec
[{
  "UID": 0,
  "PID": 1,
  "PPID": 0,
  "C": 0,
  "STIME": "10:08AM",
  "TTY": "??",
  "TIME": "0:30.02",
  "CMD": "launchd"
},
{
  "UID": 0,
  "PID": 12,
  "PPID": 1,
  "C": 0,
  "STIME": "10:08AM",
  "TTY": "??",
  "TIME": "0:03.53",
  "CMD": "kextd"
}
...

eps can be used to parse the output of jsps and may be given different keywords to be used for sorting the output. eps applies some similarity metrics (from module stringsim) to reorder and pretty print process information (in reverse order, so best matches are shown at the end of the list):

> jsps -ec | eps 'core'
 ...
 74657      ??         1:55.34    DashboardClient
 280        ??         0:00.02    AirPort Base Station Agent 
 71058      ??         0:00.56    cookied   
 268        ??         0:00.05    filecoordinationd
 15         ??         0:44.91    opendirectoryd
 261        ??         0:00.92    com.apple.dock.extra
 29         ??         1:01.50    coreservicesd
 73686      ??         3:06.89    Cornerstone
 200        ??         0:13.97    coreaudiod
> _

The similarity is computed by considering CMD and USER fields. I plan to introduce some simple customizable option to modify the fuzzy search.

proc can be started without options. It reads settings.js to setup some variables (like jsps options, refresh period and port to listen to). Here are some examples:

Getting the complete process list on the server:

> curl localhost:6969/proc 
[{
  "UID": 0,
  "PID": 1,
  "PPID": 0,
  "C": 0,
  "STIME": "10:08AM",
  "TTY": "??",
  "TIME": "0:30.02",
  "CMD": "launchd"
},
{
  "UID": 0,
  "PID": 12,
  "PPID": 1,
  "C": 0,
  "STIME": "10:08AM",
  "TTY": "??",
  "TIME": "0:03.53",
  "CMD": "kextd"
}
...

Getting the information about a single process:

> curl localhost:6969/proc/pid/12

or

> curl localhost:6969/proc/cmd/kextd

both return a list with the same process description:

[ {
  "UID": 0,
  "PID": 12,
  "PPID": 1,
  "C": 0,
  "STIME": "10:08AM",
  "TTY": "??",
  "TIME": "0:03.53",
  "CMD": "kextd"
} ]

the process description can be projected to one of the available properties, e.g. (only the property of the first match is returned):

> curl localhost:6969/proc/pid/12/CMD
kextd

Finally, there is an additional attribute that can be queried, called status. This attribute can be used for determining if the process is UP or DOWN. It can be used to connect Status Dashboard to probe and display the status of processes on a remote server.

Todo

• Write tests
• Profit
• Extend Custom settings file.
• Enhanced eps output (use graphics symbols).
• Would it be nice to start processes with POST and kill process with DELETE