terraform: New happy path works decently well

This commit is contained in:
Mitchell Hashimoto 2014-06-03 15:08:00 -07:00
parent 0c1a341d90
commit c9d8413431
5 changed files with 171 additions and 3 deletions

View File

@ -23,3 +23,13 @@ type ResourceType struct {
// ResourceProviderFactory is a function type that creates a new instance
// of a resource provider.
type ResourceProviderFactory func() (ResourceProvider, error)
func ProviderSatisfies(p ResourceProvider, n string) bool {
for _, rt := range p.Resources() {
if rt.Name == n {
return true
}
}
return false
}

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@ -3,6 +3,9 @@ package terraform
// MockResourceProvider implements ResourceProvider but mocks out all the
// calls for testing purposes.
type MockResourceProvider struct {
// Anything you want, in case you need to store extra data with the mock.
Meta interface{}
ConfigureCalled bool
ConfigureConfig map[string]interface{}
ConfigureReturnWarnings []string

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@ -1,6 +1,9 @@
package terraform
import (
"fmt"
"strings"
"github.com/hashicorp/terraform/config"
)
@ -9,7 +12,7 @@ import (
// all resources, a resource tree, a specific resource, etc.
type Terraform struct {
config *config.Config
providers []ResourceProvider
mapping map[*config.Resource]ResourceProvider
}
// Config is the configuration that must be given to instantiate
@ -27,7 +30,56 @@ type Config struct {
// time, as well as richer checks such as verifying that the resource providers
// can be properly initialized, can be configured, etc.
func New(c *Config) (*Terraform, error) {
return nil, nil
// Go through each resource and match it up to a provider
mapping := make(map[*config.Resource]ResourceProvider)
providers := make(map[string]ResourceProvider)
for _, r := range c.Config.Resources {
// Find the prefixes that match this in the order of
// longest matching first (most specific)
prefixes := matchingPrefixes(r.Type, c.Providers)
// Go through each prefix and instantiate if necessary, then
// verify if this provider is of use to us or not.
var provider ResourceProvider = nil
for _, prefix := range prefixes {
p, ok := providers[prefix]
if !ok {
var err error
p, err = c.Providers[prefix]()
if err != nil {
err = fmt.Errorf(
"Error instantiating resource provider for "+
"prefix %s: %s", prefix, err)
return nil, err
}
providers[prefix] = p
}
// Test if this provider matches what we need
if !ProviderSatisfies(p, r.Type) {
continue
}
// A match! Set it and break
provider = p
break
}
if provider == nil {
// We never found a matching provider.
return nil, fmt.Errorf(
"Provider for resource %s not found.",
r.Id())
}
mapping[r] = provider
}
return &Terraform{
config: c.Config,
mapping: mapping,
}, nil
}
func (t *Terraform) Apply(*State, *Diff) (*State, error) {
@ -41,3 +93,23 @@ func (t *Terraform) Diff(*State) (*Diff, error) {
func (t *Terraform) Refresh(*State) (*State, error) {
return nil, nil
}
// matchingPrefixes takes a resource type and a set of resource
// providers we know about by prefix and returns a list of prefixes
// that might be valid for that resource.
//
// The list returned is in the order that they should be attempted.
func matchingPrefixes(
t string,
ps map[string]ResourceProviderFactory) []string {
result := make([]string, 0, 1)
for prefix, _ := range ps {
if strings.HasPrefix(t, prefix) {
result = append(result, prefix)
}
}
// TODO(mitchellh): Order by longest prefix first
return result
}

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@ -0,0 +1,81 @@
package terraform
import (
"path/filepath"
"testing"
"github.com/hashicorp/terraform/config"
)
// This is the directory where our test fixtures are.
const fixtureDir = "./test-fixtures"
func testConfig(t *testing.T, name string) *config.Config {
c, err := config.Load(filepath.Join(fixtureDir, name, "main.tf"))
if err != nil {
t.Fatalf("err: %s", err)
}
return c
}
func testProviderFunc(n string, rs []string) ResourceProviderFactory {
resources := make([]ResourceType, len(rs))
for i, v := range rs {
resources[i] = ResourceType{
Name: v,
}
}
return func() (ResourceProvider, error) {
result := &MockResourceProvider{
Meta: n,
ResourcesReturn: resources,
}
return result, nil
}
}
func testProviderName(p ResourceProvider) string {
return p.(*MockResourceProvider).Meta.(string)
}
func testResourceMapping(tf *Terraform) map[string]ResourceProvider {
result := make(map[string]ResourceProvider)
for resource, provider := range tf.mapping {
result[resource.Id()] = provider
}
return result
}
func TestNew(t *testing.T) {
config := testConfig(t, "new-good")
tfConfig := &Config{
Config: config,
Providers: map[string]ResourceProviderFactory{
"aws": testProviderFunc("aws", []string{"aws_instance"}),
"do": testProviderFunc("do", []string{"do_droplet"}),
},
}
tf, err := New(tfConfig)
if err != nil {
t.Fatalf("err: %s", err)
}
if tf == nil {
t.Fatal("tf should not be nil")
}
mapping := testResourceMapping(tf)
if len(mapping) != 2 {
t.Fatalf("bad: %#v", mapping)
}
if testProviderName(mapping["aws_instance.foo"]) != "aws" {
t.Fatalf("bad: %#v", mapping)
}
if testProviderName(mapping["do_droplet.bar"]) != "do" {
t.Fatalf("bad: %#v", mapping)
}
}

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@ -0,0 +1,2 @@
resource "aws_instance" "foo" {}
resource "do_droplet" "bar" {}