I want to replace the variables in the python template file and mass-produce it in another file.

I had to add a lot of resources with terraform, so it was hard to copy and paste, so that's a memo.

First, prepare a template file. Set the place you want to make a variable to @ NAME @ @ PATH @ @ HOST @.

template.tf

resource "google_monitoring_uptime_check_config" "@NAME@" {
  display_name = "@NAME@"
  timeout      = "10s"

  http_check {
    use_ssl = true
    path    = "@PATH@"
    port    = "443"
  }

  monitored_resource {
    type = "uptime_url"

    labels = {
      project_id = var.project_id
      host       = "@HOST@"
    }
  }
}

Create the value you want to pass to the variable with csv.

source.csv

aaa_bbb_com,/,aaa.bbb.com
aaa_bbb_jp,/hoge,aaa.bbb.jp
aaa_bbb_co_jp,/hage,aaa.bbb.co.jp

Run python

# python mkfile.py source.csv template.txt

It is one of the created files

resource "google_monitoring_uptime_check_config" "aaa_bbb_co_jp" {
  display_name = "aaa_bbb_co_jp"
  timeout      = "10s"

  http_check {
    use_ssl = true
    path    = "/hage"
    port    = "443"
  }

  monitored_resource {
    type = "uptime_url"

    labels = {
      project_id = var.project_id
      host       = "aaa.bbb.co.jp"
    }
  }
}

If you want to combine the files,

cat create* > result.tf

Code executed

mkfile.py

# -*- coding: utf-8 -*-
import os, sys ,csv

def mkFile(srcFname, tmplFname):
    with open(srcFname) as c:
        reader = csv.reader(c)
        for row in reader:
            f1 = open(tmplFname, "r")
            f2 = open("create" + row[0] + ".txt", "w")
            for row2 in f1:
                temp = row2.replace("@NAME@", row[0]) \
                          .replace("@PATH@", row[1]) \
                          .replace("@HOST@", row[2]) 
                f2.write(temp)
            f1.close
            f2.close

    
if __name__ == '__main__': 
    if(len(sys.argv)!=3):
        print("usage: python mkfile.py source.csv template.tf")
    
    srcFname = sys.argv[1]
    tmplFname = sys.argv[2]

    #start func
    mkFile(srcFname, tmplFname)
    
    print("finished")

point

• Use the csv.reader class to read CSV files.
• For can read line by line and get comma separated values like row [0], row [1], row [2]
• Read the template file line by line, and use the replace function to process the variables you want to rewrite and the comma-separated values line by line.
• Adjust the increase / decrease of the variable you want to rewrite

                temp = row2.replace("@NAME@", row[0]) \
                          .replace("@PATH@", row[1]) \
                          .replace("@HOST@", row[2])