More explicit parsing, logging & error throwing for fetch_custom_fields_if_defined step (#12)

🙏

Author: JamesHazelcast

action.yml

@@ -54,18 +54,28 @@ runs:
           return ""
           }
           return ',"customfield_10001" : "' + teamId + '"'
-
     - name: Fetch CUSTOM_FIELDS if defined
       id: fetch_custom_fields_if_defined
       uses: actions/github-script@v6
       with:
         result-encoding: string
         script: |
-          const customFields = "${{ inputs.CUSTOM_FIELDS }}"
-          if (customFields) {
-          return ',' + customFields
+          const rawCustomFields = `${{ inputs.CUSTOM_FIELDS }}`.trim();
+          if (rawCustomFields) {
+            try {
+              const inputToParse = rawCustomFields.startsWith('{') ? rawCustomFields : `{${rawCustomFields}}`;
+              const parsedCustomFields = JSON.parse(inputToParse);
+              console.log(`Parsed CUSTOM_FIELDS: ${JSON.stringify(parsedCustomFields)}`);
+              return ',' + Object.entries(parsedCustomFields)
+                .map(([key, value]) => `"${key}": "${value}"`)
+                .join(', ');
+            } catch (error) {
+              throw new Error(
+                `Invalid CUSTOM_FIELDS format: '${rawCustomFields}'. Must be either a valid JSON object or key-value pairs in JSON format.`
+              );
+            }
           }
-          return ""
+          return '';
     - name: Create Jira issue
       id: create_jira_issue
       uses: atlassian/gajira-create@v2.0.1