Merge pull request #113 from YakDriver/templatevars

Templatevars

.bumpversion.cfg

@@ -1,9 +1,10 @@
 [bumpversion]
-current_version = 0.5.14
+current_version = 0.6.0
 commit = False
 tag = False
 tag_name = {new_version}
 
 [bumpversion:file:scratchrelaxtv/__init__.py]
 
 [bumpversion:file:setup.cfg]
+

CHANGELOG.md

@@ -1,5 +1,10 @@
 # CHANGE LOG
 
+## 0.6.0 - 2020.05.29
+
+* Output Terraform 0.12.x variables (variables without `"${}"`)
+* Add feature to extract template variables from templates and generate corresponding HCL
+
 ## 0.5.2 - 2019.07.19
 
 * Add compatibility with HCL2 / Terraform 0.12.x variables (variables without `"${}"`)

README.md

@@ -16,7 +16,8 @@ Terraform module development tool.
 1. Extract variables from `main.tf` and generate a `variables.tf` file
 1. Find missing variables in `variables.tf` and `main.tf` based on each other
 1. Generate a module use stub from a `variables.tf` file
-1. Generate a .env file with variables from `main.tf`
+1. Generate a .env or `.tfvars` file with variables from `main.tf`
+1. Generate HCL with template variables corresponding to variables from a Terraform template
 1. Delete extra *scratchrelaxtv* files
 
 # install
@@ -51,14 +52,14 @@ Here are two example workflows using *scratchrelaxtv*.
 
 ## example: generate `variables.tf`
 
-By default, *scratchrelaxtv* looks for `main.tf` and will generate a `variables.tf` file. Variables will be in the same order in `variables.tf` as they were in `main.tf`. There are options to sort variables. You can `--force` to overwrite an existing `variables.tf` file. Otherwise, *scratchrelaxtv* will generate new `variables.tf` files with each run: `variables.1.tf`, `variables.2.tf` and so on.
+By default, *scratchrelaxtv* looks for `main.tf` and will generate a `variables.tf` file. (Use the `-i` to specify a different input file.) Variables will be in the same order in `variables.tf` as they were in `main.tf`. You can sort the variables using the `-a` (ascending) and `-d` (descending) options. You can also `--force` to overwrite an existing `variables.tf` file. Otherwise, *scratchrelaxtv* will generate new `variables.tf` files with each run: `variables.1.tf`, `variables.2.tf` and so on.
 
 Assume this `main.tf`:
 ```hcl
 resource "aws_s3_bucket" "this" {
-  count  = "${var.create_bucket ? 1 : 0}"
-  bucket = "${var.bucket}"
-  region = "${var.region}"
+  count  = var.create_bucket ? 1 : 0
+  bucket = var.bucket
+  region = var.region
 }
 ```
 
@@ -100,8 +101,8 @@ Assume you already have a `main.tf` and a `variables.tf`. In this example, the `
 `main.tf`:
 ```hcl
 resource "aws_s3_bucket" "this" {
-  bucket = "${var.bucket}"
-  region = "${var.region}"
+  bucket = var.bucket
+  region = var.region
 }
 ```
 
@@ -186,29 +187,89 @@ module "tests2" {
     aws = "aws"
   }
 
-  id     = "${local.id}"
-  bucket = "${local.bucket}"
-  region = "${local.region}"
+  id     = local.id
+  bucket = local.bucket
+  region = local.region
+}
+```
+
+## example: generate a `.tfvars` file
+
+By default, when generating a `.tfvars` file, *scratchrelaxtv* looks for `variables.tf`.
+
+Assume this `variables.tf`:
+```hcl
+resource "aws_s3_bucket" "this" {
+  bucket = var.bucket
+  region = var.region
+}
+```
+
+Run *scratchrelaxtv* with the generate `.tfvars` and sort-ascending options:
+```console
+$ relaxtv -ta
+2019-06-21 20:01:35,362 - INFO - generating .tfvars file
+2019-06-21 20:01:35,362 - INFO - input file: variables.tf
+2019-06-21 20:01:35,362 - INFO - output file: terraform.tfvars
+2019-06-21 20:01:35,362 - INFO - not forcing overwrite of output file
+2019-06-21 20:01:35,362 - INFO - ordering output file ascending
+```
+
+The generated `terraform.tfvars` file:
+```
+bucket = "replace"
+region = "replace"
+```
+
+## example: generate a `.tf` file from Terraform template
+
+By default, when using template mode, *scratchrelaxtv* looks for `template.sh`. (Use the `-i` to specify a different input file.)
+
+Assume this `template.sh`:
+```bash
+#!/bin/bash
+
+build_os="${build_os}"
+build_type="${build_type}"
+```
+
+Run *scratchrelaxtv* with the `--template` and sort-ascending options:
+```console
+$ relaxtv -a --template
+2019-06-21 20:01:35,362 - INFO - extracting template variables
+2019-06-21 20:01:35,362 - INFO - input file: template.sh
+2019-06-21 20:01:35,362 - INFO - output file: template_vars.tf
+2019-06-21 20:01:35,362 - INFO - not forcing overwrite of output file
+2019-06-21 20:01:35,362 - INFO - ordering output file ascending
+```
+
+The generated `template_vars.tf` file:
+```hcl
+locals {
+  templates_vars = {
+    build_os = "replace"
+    build_type = "replace"
+  }
 }
 ```
 
 ## example: generate a `.env` (dotenv) file
 
-By default, when generating a `.env` file, *scratchrelaxtv* looks for `variables.tf`.
+By default, when generating a `.env` file, *scratchrelaxtv* looks for `variables.tf`. (Use the `-i` to specify a different input file.)
 
 Assume this `variables.tf`:
 ```hcl
 resource "aws_s3_bucket" "this" {
-  bucket = "${var.bucket}"
-  region = "${var.region}"
+  bucket = var.bucket
+  region = var.region
 }
 ```
 
 Run *scratchrelaxtv* with the generate `.env` and sort-ascending options:
 ```console
 $ relaxtv -ea
 2019-06-21 20:01:35,362 - INFO - generating .env file
-2019-06-21 20:01:35,362 - INFO - input file: main.tf
+2019-06-21 20:01:35,362 - INFO - input file: variables.tf
 2019-06-21 20:01:35,362 - INFO - output file: .env
 2019-06-21 20:01:35,362 - INFO - not forcing overwrite of output file
 2019-06-21 20:01:35,362 - INFO - ordering output file ascending
@@ -248,9 +309,9 @@ $ relaxtv -r
 *scratchrelaxtv* includes help:
 
 ```console
-$ relaxtv --help
+$ relaxtv -h
 usage: scratchrelaxtv [-h] [-i INPUT] [-o OUTPUT] [-f] [-m] [-n MODNAME] [-r]
-                      [-c] [-e] [-a | -d]
+                      [-c] [-e] [-t] [--template] [-a | -d]
 
 optional arguments:
   -h, --help            show this help message and exit
@@ -265,6 +326,8 @@ optional arguments:
   -r, --remove          remove all modstub.tf, variables.#.tf files
   -c, --check           check that all vars are listed
   -e, --env             generate .env with Terraform vars
+  -t, --tfvars          generate .tfvars with Terraform vars
+  --template            generate .tf from Terraform template vars
   -a, --asc             sort output variables in ascending order
   -d, --desc            sort output variables in descending order
 ```

scratchrelaxtv/__init__.py

@@ -20,7 +20,7 @@
 import re
 
 
-__version__ = "0.5.14"
+__version__ = "0.6.0"
 EXIT_OKAY = 0
 EXIT_NOT_OKAY = 1
 
@@ -36,6 +36,7 @@ def remove_prefix(text, prefix):
 
 def remove_files():
     """Remove files from the os that look like scratchrelaxtv files."""
+    logger.info("attempting removal of files")
     pattern = r'^(variables\.\d+|modstub(\.\d+|))\.tf$'
     for root, _, files in os.walk(os.getcwd()):
         for file in filter(lambda x: re.match(pattern, x), files):
@@ -61,20 +62,7 @@ def __init__(self, args):
         self.log_arguments()
 
     def log_arguments(self):
-        """Log all the attributes of this run."""
-        if self.args.modstub:
-            logger.info("generating module usage stub")
-        elif self.args.remove:
-            logger.info("attempting removal of files")
-        elif self.args.check:
-            logger.info("checking for missing variables")
-        elif self.args.env:
-            logger.info("generating .env file")
-        elif self.args.tfvars:
-            logger.info("generating .tfvars file")
-        else:
-            logger.info("generating variables file")
-
+        """Log the attributes of this run."""
         logger.info("input file: %s", self.args.input)
         logger.info("output file: %s", self.args.output)
 
@@ -143,6 +131,8 @@ class VarExtractor(BassExtractor):
     """
     def __init__(self, args):
         """Instantiate"""
+        logger.info("generating variables file")
+
         # defaults
         if not args.input:
             args.input = "main.tf"
@@ -180,6 +170,8 @@ class StubMaker(BassExtractor):
     """
     def __init__(self, args):
         """Instantiate"""
+        logger.info("generating module usage stub")
+
         # defaults
         if not args.input:
             args.input = "variables.tf"
@@ -226,6 +218,11 @@ class EnvGenerator(BassExtractor):
     """
     def __init__(self, args):
         """Instantiate"""
+        if args.env:
+            logger.info("generating .env file")
+        elif args.tfvars:
+            logger.info("generating .tfvars file")
+
         # defaults
         if not args.input:
             args.input = "main.tf"
@@ -278,6 +275,8 @@ class Checker(BassExtractor):
     """
     def __init__(self, args):
         """Instantiate"""
+        logger.info("checking for missing variables")
+
         # defaults
         if not args.input:
             args.input = "main.tf"
@@ -336,3 +335,48 @@ def extract(self):
             )
 
         return EXIT_OKAY
+
+
+class TemplateExtractor(BassExtractor):
+    """
+    A class that extracts variables from templates used with Terraform and
+    creates HCL showing all template variables.
+    """
+
+    var_regex = r'(?<!\$)\${([a-zA-Z][a-zA-Z0-9_-]+)}'
+
+    def __init__(self, args):
+        """Instantiate"""
+        logger.info("extracting template variables")
+
+        # defaults
+        if not args.input:
+            args.input = "template.sh"
+
+        if not args.output:
+            args.output = "template_vars.tf"
+
+        super().__init__(args)
+
+    def write_file(self):
+        """Output vars to .tf file."""
+        self._find_non_existing_filename()
+
+        with open(self.args.output, "w", encoding='utf_8') as file_handle:
+
+            file_handle.write('locals {\n')
+            file_handle.write('  templates_vars = {\n')
+            for tf_var in self.tf_vars:
+                file_handle.write("".join([
+                    "    ",
+                    tf_var,
+                    " = ",
+                    "\"replace\"\n"]))
+            file_handle.write('  }\n}\n')
+
+    def extract(self):
+        """Extract vars from .tf file."""
+        self.find_vars_in_file(self.var_regex)
+        self.write_file()
+
+        return EXIT_OKAY

scratchrelaxtv/cli.py

@@ -41,6 +41,8 @@ def parse_args(args):
                       help="generate .env with Terraform vars")
     task.add_argument("-t", "--tfvars", default=False, action="store_true",
                       help="generate .tfvars with Terraform vars")
+    task.add_argument("--template", default=False, action="store_true",
+                      help="generate .tf from Terraform template vars")
 
     sort_order = parser.add_mutually_exclusive_group()
     sort_order.add_argument("-a", "--asc", action="store_true",
@@ -65,6 +67,8 @@ def main():
         extractor = scratchrelaxtv.Checker(args)
     elif args.env or args.tfvars:
         extractor = scratchrelaxtv.EnvGenerator(args)
+    elif args.template:
+        extractor = scratchrelaxtv.TemplateExtractor(args)
     else:
         extractor = scratchrelaxtv.VarExtractor(args)
 

setup.cfg

@@ -3,7 +3,7 @@ name = scratchrelaxtv
 description = Terraform developer tool to extract variables and generate variables.tf files.
 long_description = file: README.md, CHANGELOG.md
 long_description_content_type = text/markdown
-version = 0.5.14
+version = 0.6.0
 author = YakDriver
 author_email = [email protected]
 url = https://github.com/YakDriver/scratchrelaxtv

tests/template.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+build_os="${build_os}"
+build_type="${build_type}"
+
+exec &> "${userdata_log}"
+
+build_slug="${build_slug}"
+export AWS_REGION="${aws_region}"
+debug_mode="${debug}"
+debug_mode="$${not_a_var}"

tests/template_vars.tf

@@ -0,0 +1,10 @@
+locals {
+  templates_vars = {
+    aws_region = "replace"
+    build_os = "replace"
+    build_slug = "replace"
+    build_type = "replace"
+    debug = "replace"
+    userdata_log = "replace"
+  }
+}

tests/test_scratchrelaxtv.py

@@ -6,7 +6,7 @@
 import os
 from contextlib import contextmanager
 from scratchrelaxtv import cli, Checker, StubMaker, VarExtractor,\
-    EnvGenerator, EXIT_OKAY, remove_files
+    EnvGenerator, EXIT_OKAY, remove_files, TemplateExtractor
 
 
 @contextmanager
@@ -180,3 +180,23 @@ def test_gen_tfvars():
             second_list = file_handle.read().splitlines()
         assert first_list == second_list
         os.remove(filename)
+
+
+def test_template():
+    """Test extracting variables."""
+    with change_dir("tests"):
+        filename = "template_vars.1.tf"
+        if os.path.isfile(filename):
+            os.remove(filename)
+
+        args = cli.parse_args(["-fa", "--template", "-o", filename])
+
+        extractor = TemplateExtractor(args)
+
+        assert extractor.extract() == EXIT_OKAY
+        with open("template_vars.tf", "r", encoding='utf_8') as file_handle:
+            first_list = file_handle.read().splitlines()
+        with open(filename, "r", encoding='utf_8') as file_handle:
+            second_list = file_handle.read().splitlines()
+        assert first_list == second_list
+        os.remove(filename)