feat: outline of plan output changes (#213)

* initial draft Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * amend `comment_outline` reference Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * retry in action.yaml instead now Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * fix missing `shell: bash` Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * retry Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * retry Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * remove unused code Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * only add outline if present Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * fix rogue `const` Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * fix erroneous reference Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * fix missing brace Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * retry with tweaked conditional Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * try without any comment_outline Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * drastically shorten changed_lines length Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * try `substring` instead of `slice` Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * y Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * retry Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> * ready for review Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com> --------- Signed-off-by: Rishav Dhar <19497993+rdhar@users.noreply.github.com>
DevSecTop · May 19, 2024 · 85327f7 · 85327f7
1 parent 2db47a4
commit 85327f7
Show file tree

Hide file tree

Showing 3 changed files with 48 additions and 7 deletions.
diff --git a/README.md b/README.md
@@ -119,6 +119,7 @@ Use-case: Provision resources with a backend, followed by destruction without co
 | `cli_uses`</br>Example: tofu                         | String name of TF CLI to use and override default assumption from wrapper environment variable.                                          |
 | `command_input`</br>Example: -tf=plan -workspace=dev | String input to run TF CLI command with arguments directly via workflow automation.                                                      |
 | `fmt_enable`</br>Default: true                       | Boolean flag to enable TF fmt command and display diff of changes.                                                                       |
+| `plan_outline`</br>Default: true                     | Boolean flag to output TF plan outline of changes.                                                                                       |
 | `recreate_comment`</br>Default: true                 | Boolean flag to recreate PR comment on update instead of editing the existing one.                                                       |
 | `validate_enable`</br>Default: false                 | Boolean flag to enable TF validate command check.                                                                                        |
 | `var_file_from_workspace`</br>Default: false         | Boolean flag to re-use TF `-workspace` as `-var-file` argument, if supplied.                                                             |

diff --git a/action.yml b/action.yml
@@ -29,6 +29,9 @@ inputs:
   fmt_enable:
     description: Boolean flag to enable TF fmt command and display diff of changes.
     default: true
+  plan_outline:
+    description: Boolean flag to output TF plan outline of changes.
+    default: true
   recreate_comment:
     description: Boolean flag to recreate PR comment on update instead of editing the existing one.
     default: true
@@ -306,24 +309,24 @@ runs:
       shell: bash
       run: |
         # Remove lines related to fetching the state of resources and truncate
-        # before the last 66000 characters to capture the final change summary.
+        # before the last 48000 characters to capture the final change summary.
         tf_output_raw=$(cat <<'EOTF'
         ${{ steps.apply.outputs.stderr || steps.apply.outputs.stdout || steps.plan.outputs.stderr || steps.plan.outputs.stdout || steps.force_unlock.outputs.stderr || steps.force_unlock.outputs.stdout || steps.workspace.outputs.stderr || steps.validate.outputs.stderr || steps.init.outputs.stderr }}
         EOTF
         )
         echo 'tf_output<<EOTF' >> $GITHUB_OUTPUT
         echo "$tf_output_raw" |
           grep -vE ': Creating...|: Creation complete after|: Destroying...|: Destruction complete after|: Modifications complete after|: Modifying...|: Provisioning with|: Read complete after|: Reading...|: Refreshing state...|: Still creating...|: Still destroying...|: Still modifying...|: Still reading...|. This may take a few moments...' |
-          tail -c 66000 >> $GITHUB_OUTPUT
+          tail -c 48000 >> $GITHUB_OUTPUT
         echo 'EOTF' >> $GITHUB_OUTPUT
 
-        # This time, truncate after the first 12000 characters instead.
+        # This time, truncate after the first 6000 characters instead.
         tf_fmt_raw=$(cat <<'EOTF'
         ${{ steps.fmt.outputs.stdout }}
         EOTF
         )
         echo 'tf_fmt<<EOTF' >> $GITHUB_OUTPUT
-        echo "$tf_fmt_raw" | head -c 12000 >> $GITHUB_OUTPUT
+        echo "$tf_fmt_raw" | head -c 6000 >> $GITHUB_OUTPUT
         echo 'EOTF' >> $GITHUB_OUTPUT
 
     # Add or update PR comment with rendered TF output before exiting.
@@ -335,13 +338,15 @@ runs:
         matrix: ${{ toJSON(matrix) }}
         recreate_comment: ${{ inputs.recreate_comment }}
         run_attempt: ${{ github.run_attempt }}
+        tf_chdir: ${{ steps.arguments.outputs.tf_cwd }}
         tf_command: ${{ steps.parsed.outputs.command }}
         tf_fmt: ${{ steps.render.outputs.tf_fmt }}
         tf_output: ${{ steps.render.outputs.tf_output }}
         tf_plan_id: ${{ steps.arguments.outputs.tf_plan_id }}
+        tf_plan_outline: ${{ inputs.plan_outline && steps.plan.outcome == 'success' }}
       with:
         retries: 3
-        script: await require(`${process.env.GITHUB_ACTION_PATH}/scripts/comment_tf_output.js`)({ github, context, core });
+        script: await require(`${process.env.GITHUB_ACTION_PATH}/scripts/comment_tf_output.js`)({ github, context, core, exec });
 
     # Remove PR comment reaction to indicate that the workflow has ended.
     - name: Remove reaction

diff --git a/scripts/comment_tf_output.js b/scripts/comment_tf_output.js
@@ -1,4 +1,4 @@
-module.exports = async ({ github, context, core }) => {
+module.exports = async ({ github, context, core, exec }) => {
   // Display latest TF change summary as the output header.
   const comment_summary = process.env.tf_output
     .split("\n")
@@ -39,9 +39,43 @@ ${process.env.tf_fmt}
     repo: context.repo.repo,
   });
 
+  // Parse the TFplan file to extract an outline of changes.
+  let comment_outline = "";
+  if (process.env.tf_plan_outline) {
+    // Parse TFplan file.
+    let tfplan = "";
+    const data_handler = (data) => {
+      tfplan += data.toString();
+    };
+    const options = {
+      listeners: {
+        stdout: data_handler,
+        stderr: data_handler,
+      },
+    };
+    await exec.exec(process.env.TF_CLI_USES, [`-chdir=${process.env.tf_chdir}`, "show", "-no-color", "tfplan"], options);
+
+    // Create a summary from lines starting with '  # ' without this prefix.
+    // prefix from the first 12000 characters.
+    const changed_lines = tfplan
+      .split("\n")
+      .filter((line) => line.startsWith("  # "))
+      .map((line) => line.slice(4));
+
+    // Create a collapsible summary of changes if any.
+    comment_outline = changed_lines.length
+      ? `<details><summary>Outline of changes.</summary>
+
+\`\`\`hcl
+${changed_lines.join("\n").substring(0, 12000)}
+\`\`\`
+</details>`
+      : "";
+  }
+
   // Display the: TF command, TF output, and workflow authorip.
   const comment_output = `
-  <details><summary>${comment_summary}</br>
+<details><summary>${comment_summary}</br>
 
 ###### ${context.workflow} by @${context.actor} via [${context.eventName}](${check_url}) at ${context.payload.pull_request?.updated_at || context.payload.comment?.updated_at}.</summary>
 
@@ -57,6 +91,7 @@ ${process.env.tf_output}
 <!-- pre_output -->
 
 ${comment_fmt}
+${comment_outline}
 ${comment_output}
 
 <!-- post_output -->