feat: add content block on generate_hcl

[katcipis]

This PRs changes the behavior of code generation using generate_hcl. Instead of generating code by doing:

generate_hcl {
  terraform {
  }
}

All generated HCL must be inside the content block, like this:

generate_hcl {
  content {
    terraform {
    }
  }
}

A full example:

#!/bin/bash

set -o nounset
set -o errexit

basedir=$(mktemp -d)

cd "${basedir}"

# We need the project root config since it is not git
cat > terramate.tm.hcl <<- EOM
terramate {
  config {
  }
}
EOM

mkdir -p stacks/stack-{1,2}
terramate stacks init stacks/stack-{1,2}

# Defining some code for all stacks
# Globals are defined on root and also on stacks, to showcase possibilities
# Inspired on: https://github.com/mineiros-io/terramate-blueprint-iac-github/tree/main/stacks/repositories/teamA
cat > stacks/terramate.tm.hcl <<- EOM
globals {
    tf_version = "1.1.3"
    gh_owner = "the-awesome-mineiros"
    gh_provider_version = "4.19.1"
}

generate_hcl "provider.tf" {
    content {
        provider "github" {
          owner = global.gh_owner
        }

        terraform {
          required_providers {
            github = {
              source  = "integrations/github"
              version = global.gh_provider_version
            }
          }
        }

        terraform {
          required_version = global.tf_version
        }
    }
}

generate_hcl "main.tf" {
  content {
      module "repositories" {
        source = "../../../modules/terramate-github-repositories"

        repositories        = global.repositories
        repository_defaults = global.repository_defaults
        member_map          = global.member_map
      }
  }
}
EOM

# Now add some per stack globals

cat > stacks/stack-1/terramate.tm.hcl <<- EOM
globals {
    repositories = [
        {
            name = "stack-1"
            visibility = "private"
        }
    ]
    repository_defaults = {
        config = "stack-1"
    }
    member_map  = {
        "first.lastname" = "powerpuffGirls69"
    }
}
stack {}
EOM

cat > stacks/stack-2/terramate.tm.hcl <<- EOM
globals {
    repositories = [
        {
            name = "stack-2"
            visibility = "public"
        }
    ]
    repository_defaults = {
        config = "stack-2"
    }
    member_map  = {
        "first.lastname" = "onePunchMan666"
    }
}
stack {}
EOM


echo "initial tree"
tree

echo
echo "generating code for all stacks"
terramate generate

echo "tree after generating code"
tree

echo
echo "checking generated main.tf files"
terramate run -- cat main.tf

echo
echo "checking generated provider.tf files"
terramate run -- cat provider.tf

[mariux]

lgtm

[codecov-commenter]

Codecov Report

Merging #220 (5617d26) into main (00e6f7b) will increase coverage by 0.06%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #220      +/-   ##
==========================================
+ Coverage   63.59%   63.66%   +0.06%     
==========================================
  Files          30       29       -1     
  Lines        5390     5403      +13     
==========================================
+ Hits         3428     3440      +12     
- Misses       1779     1780       +1     
  Partials      183      183              

Flag	Coverage Δ
tests	63.66% <100.00%> (+0.06%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
generate/genhcl/genhcl.go	93.02% <100.00%> (+1.07%)	⬆️
test/hcl.go	53.16% <0.00%> (-4.59%)	⬇️
cmd/terramate/cli/cli.go	0.00% <0.00%> (ø)
run/run.go
hcl/hcl.go	81.68% <0.00%> (+0.24%)	⬆️

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[mariux]

why do we manually check those... can't we use the go structures to let HCL library check this for us?

[katcipis]

But then we need to define the struct/type (which is a form of manual definition also, but more descriptive) and I didn't see any immediate use for the struct since I just grab the whole content body after validation (it is dynamic, I dont know the structure of the content body), if we had more specific attributes that we need we could indeed use a Go struct with some specific fields.

[katcipis]

When you mentioned "Go Structures" I immediately thought of hclsimple.

Which in this case seems less helpful IMO (but quite helpful on some scenarios), but now I think maybe you meant the BodySchema.

Which could make some of the basic validation for us, will take a look (haven't used it yet, sorry for the ignorance).

[i4ki]

lgtm