block_fastly_service_v1_cachesetting.go

package fastly

import (
	"fmt"
	"log"
	"strings"

	gofastly "github.com/fastly/go-fastly/v3/fastly"
	"github.com/hashicorp/terraform-plugin-sdk/helper/schema"
)

type CacheSettingServiceAttributeHandler struct {
	*DefaultServiceAttributeHandler
}

func NewServiceCacheSetting(sa ServiceMetadata) ServiceAttributeDefinition {
	return &CacheSettingServiceAttributeHandler{
		&DefaultServiceAttributeHandler{
			key:             "cache_setting",
			serviceMetadata: sa,
		},
	}
}

func (h *CacheSettingServiceAttributeHandler) Process(d *schema.ResourceData, latestVersion int, conn *gofastly.Client) error {
	oc, nc := d.GetChange(h.GetKey())
	if oc == nil {
		oc = new(schema.Set)
	}
	if nc == nil {
		nc = new(schema.Set)
	}

	oldSet := oc.(*schema.Set)
	newSet := nc.(*schema.Set)

	setDiff := NewSetDiff(func(resource interface{}) (interface{}, error) {
		t, ok := resource.(map[string]interface{})
		if !ok {
			return nil, fmt.Errorf("resource failed to be type asserted: %+v", resource)
		}
		return t["name"], nil
	})

	diffResult, err := setDiff.Diff(oldSet, newSet)
	if err != nil {
		return err
	}

	// DELETE removed resources
	for _, resource := range diffResult.Deleted {
		resource := resource.(map[string]interface{})
		opts := gofastly.DeleteCacheSettingInput{
			ServiceID:      d.Id(),
			ServiceVersion: latestVersion,
			Name:           resource["name"].(string),
		}

		log.Printf("[DEBUG] Fastly Cache Settings removal opts: %#v", opts)
		err := conn.DeleteCacheSetting(&opts)
		if errRes, ok := err.(*gofastly.HTTPError); ok {
			if errRes.StatusCode != 404 {
				return err
			}
		} else if err != nil {
			return err
		}
	}

	// CREATE new resources
	for _, resource := range diffResult.Added {
		opts, err := buildCacheSetting(resource.(map[string]interface{}))
		if err != nil {
			log.Printf("[DEBUG] Error building Cache Setting: %s", err)
			return err
		}
		opts.ServiceID = d.Id()
		opts.ServiceVersion = latestVersion

		log.Printf("[DEBUG] Fastly Cache Settings Addition opts: %#v", opts)
		_, err = conn.CreateCacheSetting(opts)
		if err != nil {
			return err
		}
	}

	// UPDATE modified resources
	//
	// NOTE: although the go-fastly API client enables updating of a resource by
	// its 'name' attribute, this isn't possible within terraform due to
	// constraints in the data model/schema of the resources not having a uid.
	for _, resource := range diffResult.Modified {
		resource := resource.(map[string]interface{})

		opts := gofastly.UpdateCacheSettingInput{
			ServiceID:      d.Id(),
			ServiceVersion: latestVersion,
			Name:           resource["name"].(string),
		}

		// only attempt to update attributes that have changed
		modified := setDiff.Filter(resource, oldSet)

		// NOTE: where we transition between interface{} we lose the ability to
		// infer the underlying type being either a uint vs an int. This
		// materializes as a panic (yay) and so it's only at runtime we discover
		// this and so we've updated the below code to convert the type asserted
		// int into a uint before passing the value to gofastly.Uint().
		if v, ok := modified["action"]; ok {
			opts.Action = gofastly.CacheSettingAction(v.(string))
		}
		if v, ok := modified["ttl"]; ok {
			opts.TTL = gofastly.Uint(uint(v.(int)))
		}
		if v, ok := modified["stale_ttl"]; ok {
			opts.StaleTTL = gofastly.Uint(uint(v.(int)))
		}
		if v, ok := modified["cache_condition"]; ok {
			opts.CacheCondition = gofastly.String(v.(string))
		}

		log.Printf("[DEBUG] Update Cache Setting Opts: %#v", opts)
		_, err := conn.UpdateCacheSetting(&opts)
		if err != nil {
			return err
		}
	}

	return nil
}

func (h *CacheSettingServiceAttributeHandler) Read(d *schema.ResourceData, s *gofastly.ServiceDetail, conn *gofastly.Client) error {
	log.Printf("[DEBUG] Refreshing Cache Settings for (%s)", d.Id())
	cslList, err := conn.ListCacheSettings(&gofastly.ListCacheSettingsInput{
		ServiceID:      d.Id(),
		ServiceVersion: s.ActiveVersion.Number,
	})
	if err != nil {
		return fmt.Errorf("[ERR] Error looking up Cache Settings for (%s), version (%v): %s", d.Id(), s.ActiveVersion.Number, err)
	}

	csl := flattenCacheSettings(cslList)

	if err := d.Set(h.GetKey(), csl); err != nil {
		log.Printf("[WARN] Error setting Cache Settings for (%s): %s", d.Id(), err)
	}
	return nil
}

func (h *CacheSettingServiceAttributeHandler) Register(s *schema.Resource) error {
	s.Schema[h.GetKey()] = &schema.Schema{
		Type:     schema.TypeSet,
		Optional: true,
		Elem: &schema.Resource{
			Schema: map[string]*schema.Schema{
				// required fields
				"name": {
					Type:        schema.TypeString,
					Required:    true,
					Description: "Unique name for this Cache Setting. It is important to note that changing this attribute will delete and recreate the resource",
				},
				"action": {
					Type:        schema.TypeString,
					Optional:    true,
					Description: `One of cache, pass, or restart, as defined on Fastly's documentation under "[Caching action descriptions](https://docs.fastly.com/en/guides/controlling-caching#caching-action-descriptions)"`,
				},
				// optional
				"cache_condition": {
					Type:        schema.TypeString,
					Optional:    true,
					Default:     "",
					Description: "Name of already defined `condition` used to test whether this settings object should be used. This `condition` must be of type `CACHE`",
				},
				"stale_ttl": {
					Type:        schema.TypeInt,
					Optional:    true,
					Description: `Max "Time To Live" for stale (unreachable) objects`,
				},
				"ttl": {
					Type:        schema.TypeInt,
					Optional:    true,
					Description: "The Time-To-Live (TTL) for the object",
				},
			},
		},
	}
	return nil
}

func buildCacheSetting(cacheMap interface{}) (*gofastly.CreateCacheSettingInput, error) {
	df := cacheMap.(map[string]interface{})
	opts := gofastly.CreateCacheSettingInput{
		Name:           df["name"].(string),
		StaleTTL:       uint(df["stale_ttl"].(int)),
		CacheCondition: df["cache_condition"].(string),
	}

	if v, ok := df["ttl"]; ok {
		opts.TTL = uint(v.(int))
	}

	act := strings.ToLower(df["action"].(string))
	switch act {
	case "cache":
		opts.Action = gofastly.CacheSettingActionCache
	case "pass":
		opts.Action = gofastly.CacheSettingActionPass
	case "restart":
		opts.Action = gofastly.CacheSettingActionRestart
	}

	return &opts, nil
}

func flattenCacheSettings(csList []*gofastly.CacheSetting) []map[string]interface{} {
	var csl []map[string]interface{}
	for _, cl := range csList {
		// Convert Cache Settings to a map for saving to state.
		clMap := map[string]interface{}{
			"name":            cl.Name,
			"action":          cl.Action,
			"cache_condition": cl.CacheCondition,
			"stale_ttl":       cl.StaleTTL,
			"ttl":             cl.TTL,
		}

		// prune any empty values that come from the default string value in structs
		for k, v := range clMap {
			if v == "" {
				delete(clMap, k)
			}
		}

		csl = append(csl, clMap)
	}

	return csl
}