chore: Document functions (based on google style guide) (#317)

hooks/terraform_validate.sh

@@ -15,6 +15,19 @@ function main {
   terraform_validate_
 }
 
+#######################################################################
+# Parse args and filenames passed to script and populate respective
+# global variables with appropriate values
+# Globals (init and populate):
+#   ARGS (array) arguments that configure wrapped tool behavior
+#   INIT_ARGS (array) arguments to `terraform init` command
+#   ENVS (array) environment variables that will be used with
+#     `terraform` commands
+#   FILES (array) filenames to check
+# Arguments:
+#   $@ (array) all specified in `hooks.[].args` in
+#     `.pre-commit-config.yaml` and filenames.
+#######################################################################
 function parse_cmdline_ {
   declare argv
   argv=$(getopt -o e:i:a: --long envs:,init-args:,args: -- "$@") || return
@@ -46,6 +59,24 @@ function parse_cmdline_ {
   done
 }
 
+#######################################################################
+# Wrapper around `terraform validate` tool that checks if code is valid
+# 1. Export provided env var K/V pairs to environment
+# 2. Because hook runs on whole dir, reduce file paths to uniq dir paths
+# 3. In each dir that have *.tf files:
+# 3.1. Check if `.terraform` dir exists and if not - run `terraform init`
+# 3.2. Run `terraform validate`
+# 3.3. If at least 1 check failed - change exit code to non-zero
+# 4. Complete hook execution and return exit code
+# Globals:
+#   ARGS (array) arguments that configure wrapped tool behavior
+#   INIT_ARGS (array) arguments for `terraform init` command`
+#   ENVS (array) environment variables that will be used with
+#     `terraform` commands
+#   FILES (array) filenames to check
+# Outputs:
+#   If failed - print out hook checks status
+#######################################################################
 function terraform_validate_ {
 
   # Setup environment variables