Service offering resource update

[jeanvetorello]

Overview

This PR completely updates the cloudstack_service_offering resource to support CloudStack API version 4.21, achieving 100% SDK coverage with all 54 parameters from CreateServiceOfferingParams fully implemented.

Motivation

I needed to update the Service Offering API to the latest CloudStack version (4.21) to support modern features like GPU configuration, advanced IOPS settings, and dynamic scaling. The existing implementation was missing critical parameters and had several drift issues.

What's New

1. Complete API v4.21 Coverage (54/54 Parameters)

All parameters from CloudStack Go SDK v2 CreateServiceOfferingParams are now implemented:

CPU & Memory:

• cpu_number, cpu_speed, memory
• customized, min_cpu_number, max_cpu_number
• min_memory, max_memory

GPU Support (NEW):

• gpu_card - GPU card name (maps to gpucardid)
• gpu_type - vGPU profile UUID (maps to vgpuprofileid)
• gpu_count - Number of GPUs

Storage:

• storage_type, storage_tags, host_tags
• root_disk_size, encrypt_root
• provisioning_type, cache_mode

IOPS & Bandwidth (12 parameters):

• bytes_read_rate, bytes_write_rate
• bytes_read_rate_max, bytes_write_rate_max
• bytes_read_rate_max_length, bytes_write_rate_max_length
• iops_read_rate, iops_write_rate
• iops_read_rate_max, iops_write_rate_max
• iops_read_rate_max_length, iops_write_rate_max_length

Performance:

• disk_iops_min, disk_iops_max
• hypervisor_snapshot_reserve
• offer_ha, limit_cpu_use
• dynamic_scaling_enabled
• customized_iops

System & Domain:

• is_system, system_vm_type
• zone_id, domain_id
• is_volatile, deployment_planner

Advanced:

• service_offering_details (map for custom settings)

2. Bug Fixes

Fixed service_offering_details Drift

• Problem: CloudStack adds system keys (External:key, External:value, purge.db.entities) causing state drift
• Solution: Implemented filtering in Read function (lines 847-863) to only track user-configured keys

Fixed customized Parameter Logic

• Problem: Incorrect handling of Fixed vs Custom offerings
• Solution: Smart conditional logic based on CPU/memory presence:
  • If cpu_number + memory provided → customized = false (Fixed Offering)
  • If customized = true + min/max → Custom Constrained
  • If customized = true + no limits → Custom Unconstrained

Identified ForceNew Parameters (47 of 54)

• Problem: Most CloudStack Service Offering parameters are immutable after creation
• Solution: Added ForceNew: true to 47 parameters based on CloudStack API limitations
• Updateable: Only display_text, host_tags, and storage_tags can be updated in-place

3. Comprehensive Testing

Added 4 new tests covering all CloudStack UI offering types:

• TestAccServiceOfferingTypeFixed - Fixed CPU/memory
• TestAccServiceOfferingTypeCustomConstrained - Customizable with limits
• TestAccServiceOfferingTypeCustomUnconstrained - Fully customizable
• TestAccServiceOfferingAllUITypes - All types together

Total: 17 tests (13 existing + 4 new)

4. Complete Documentation

Created comprehensive documentation in website/docs/r/service_offering.html.markdown:

• Detailed explanation of all 3 offering types with decision tree
• GPU configuration examples (A6000, A100, H100, RTX 4090, Multi-GPU)
• IOPS/bandwidth configuration examples
• High-performance offerings
• ForceNew behavior documentation
• CloudStack API behavior notes