terraform/builtin/providers/google/metadata.go

72 lines
1.8 KiB
Go

package google
import (
"fmt"
"google.golang.org/api/compute/v1"
)
const FINGERPRINT_RETRIES = 10
const FINGERPRINT_FAIL = "Invalid fingerprint."
// Since the google compute API uses optimistic locking, there is a chance
// we need to resubmit our updated metadata. To do this, you need to provide
// an update function that attempts to submit your metadata
func MetadataRetryWrapper(update func() error) error {
attempt := 0
for attempt < FINGERPRINT_RETRIES {
err := update()
if err != nil && err.Error() == FINGERPRINT_FAIL {
attempt++
} else {
return err
}
}
return fmt.Errorf("Failed to update metadata after %d retries", attempt)
}
// Update the metadata (serverMD) according to the provided diff (oldMDMap v
// newMDMap).
func MetadataUpdate(oldMDMap map[string]interface{}, newMDMap map[string]interface{}, serverMD *compute.Metadata) {
curMDMap := make(map[string]string)
// Load metadata on server into map
for _, kv := range serverMD.Items {
// If the server state has a key that we had in our old
// state, but not in our new state, we should delete it
_, okOld := oldMDMap[kv.Key]
_, okNew := newMDMap[kv.Key]
if okOld && !okNew {
continue
} else {
curMDMap[kv.Key] = *kv.Value
}
}
// Insert new metadata into existing metadata (overwriting when needed)
for key, val := range newMDMap {
curMDMap[key] = val.(string)
}
// Reformat old metadata into a list
serverMD.Items = nil
for key, val := range curMDMap {
v := val
serverMD.Items = append(serverMD.Items, &compute.MetadataItems{
Key: key,
Value: &v,
})
}
}
// Format metadata from the server data format -> schema data format
func MetadataFormatSchema(md *compute.Metadata) map[string]interface{} {
newMD := make(map[string]interface{})
for _, kv := range md.Items {
newMD[kv.Key] = *kv.Value
}
return newMD
}