ResiLien
/
terraform
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

states: Port stringer implementation from terraform.State 

Our existing core tests make extensive use of the string representation
of a state for comparison purposes, because they were written before we
began making use of helper packages like "cmp".

To avoid the need to rewrite all of those tests and potentially break
them, we will instead port that particular rendering as closely as
possible but mark it with a comment sternly warning not to use it for
anything new.

We don't want to use this moving forward for a number of reasons, but
most notably:

 - printing out whole before and after state representations makes it
   hard to find a subtle difference in outcome when a test fails, while
   "cmp" can provide us with a real diff.

 - this string serialization is constrained by the capabilities of
   Terraform prior to our new state models, and so it does not
   comprehensively represent all possibilities in the new world.

 - it will probably behave oddly/poorly when given states containing
   features that arrived after it was written, even though I made a
   best effort here to make it do something reasonable in situations
   I thought about.
This commit is contained in:
Martin Atkins 2018-07-31 15:26:51 -07:00
parent 424afe0ace
commit cf6892275a
1 changed files with 264 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

264
states/state_string.go Normal file
View File

@ -0,0 +1,264 @@
package states
import (
"bufio"
"bytes"
"encoding/json"
"fmt"
"sort"
"strings"
ctyjson "github.com/zclconf/go-cty/cty/json"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/config/hcl2shim"
)
// String returns a rather-odd string representation of the entire state.
//
// This is intended to match the behavior of the older terraform.State.String
// method that is used in lots of existing tests. It should not be used in
// new tests: instead, use "cmp" to directly compare the state data structures
// and print out a diff if they do not match.
//
// This method should never be used in non-test code, whether directly by call
// or indirectly via a %s or %q verb in package fmt.
func (s *State) String() string {
if s == nil {
return "<nil>"
}
var buf bytes.Buffer
for _, m := range s.Modules {
mStr := m.testString()
// If we're the root module, we just write the output directly.
if m.Addr.IsRoot() {
buf.WriteString(mStr + "\n")
continue
}
// We need to build out a string that resembles the not-quite-standard
// format that terraform.State.String used to use, where there's a
// "module." prefix but then just a chain of all of the module names
// without any further "module." portions.
buf.WriteString("module")
for _, step := range m.Addr {
buf.WriteByte('.')
buf.WriteString(step.Name)
if step.InstanceKey != addrs.NoKey {
buf.WriteByte('[')
buf.WriteString(step.InstanceKey.String())
buf.WriteByte(']')
}
}
buf.WriteByte('\n')
s := bufio.NewScanner(strings.NewReader(mStr))
for s.Scan() {
text := s.Text()
if text != "" {
text = " " + text
}
buf.WriteString(fmt.Sprintf("%s\n", text))
}
}
return strings.TrimSpace(buf.String())
}
// testString is used to produce part of the output of State.String. It should
// never be used directly.
func (m *Module) testString() string {
var buf bytes.Buffer
if len(m.Resources) == 0 {
buf.WriteString("<no state>")
}
// We use AbsResourceInstance here, even though everything belongs to
// the same module, just because we have a sorting behavior defined
// for those but not for just ResourceInstance.
addrsOrder := make([]addrs.AbsResourceInstance, 0, len(m.Resources))
for _, rs := range m.Resources {
for ik := range rs.Instances {
addrsOrder = append(addrsOrder, rs.Addr.Instance(ik).Absolute(addrs.RootModuleInstance))
}
}
sort.Slice(addrsOrder, func(i, j int) bool {
return addrsOrder[i].Less(addrsOrder[j])
})
for _, fakeAbsAddr := range addrsOrder {
addr := fakeAbsAddr.Resource
rs := m.Resource(addr.ContainingResource())
is := m.ResourceInstance(addr)
// Here we need to fake up a legacy-style address as the old state
// types would've used, since that's what our tests against those
// old types expect. The significant difference is that instancekey
// is dot-separated rather than using index brackets.
k := addr.ContainingResource().String()
if addr.Key != addrs.NoKey {
switch tk := addr.Key.(type) {
case addrs.IntKey:
k = fmt.Sprintf("%s.%d", k, tk)
default:
// No other key types existed for the legacy types, so we
// can do whatever we want here. We'll just use our standard
// syntax for these.
k = k + tk.String()
}
}
id := legacyInstanceObjectID(is.Current)
taintStr := ""
if is.Current != nil && is.Current.Status == ObjectTainted {
taintStr = " (tainted)"
}
deposedStr := ""
if len(is.Deposed) > 0 {
deposedStr = fmt.Sprintf(" (%d deposed)", len(is.Deposed))
}
buf.WriteString(fmt.Sprintf("%s:%s%s\n", k, taintStr, deposedStr))
buf.WriteString(fmt.Sprintf(" ID = %s\n", id))
buf.WriteString(fmt.Sprintf(" provider = %s\n", rs.ProviderConfig.String()))
// Attributes were a flatmap before, but are not anymore. To preserve
// our old output as closely as possible we need to do a conversion
// to flatmap. Normally we'd want to do this with schema for
// accuracy, but for our purposes here it only needs to be approximate.
// This should produce an identical result for most cases, though
// in particular will differ in a few cases:
// - The keys used for elements in a set will be different
// - Values for attributes of type cty.DynamicPseudoType will be
// misinterpreted (but these weren't possible in old world anyway)
var attributes map[string]string
if obj := is.Current; obj != nil {
switch {
case obj.AttrsFlat != nil:
// Easy (but increasingly unlikely) case: the state hasn't
// actually been upgraded to the new form yet.
attributes = obj.AttrsFlat
case obj.AttrsJSON != nil:
ty, err := ctyjson.ImpliedType(obj.AttrsJSON)
if err == nil {
val, err := ctyjson.Unmarshal(obj.AttrsJSON, ty)
if err == nil {
attributes = hcl2shim.FlatmapValueFromHCL2(val)
}
}
}
}
attrKeys := make([]string, 0, len(attributes))
for ak, _ := range attributes {
if ak == "id" {
continue
}
attrKeys = append(attrKeys, ak)
}
sort.Strings(attrKeys)
for _, ak := range attrKeys {
av := attributes[ak]
buf.WriteString(fmt.Sprintf(" %s = %s\n", ak, av))
}
// CAUTION: Since deposed keys are now random strings instead of
// incrementing integers, this result will not be deterministic
// if there is more than one deposed object.
var idx int
for _, t := range is.Deposed {
id := legacyInstanceObjectID(t)
taintStr := ""
if t.Status == ObjectTainted {
taintStr = " (tainted)"
}
buf.WriteString(fmt.Sprintf(" Deposed ID %d = %s%s\n", idx+1, id, taintStr))
idx++
}
if obj := is.Current; obj != nil && len(obj.Dependencies) > 0 {
buf.WriteString(fmt.Sprintf("\n Dependencies:\n"))
for _, dep := range obj.Dependencies {
buf.WriteString(fmt.Sprintf(" %s\n", dep.String()))
}
}
}
if len(m.OutputValues) > 0 {
buf.WriteString("\nOutputs:\n\n")
ks := make([]string, 0, len(m.OutputValues))
for k := range m.OutputValues {
ks = append(ks, k)
}
sort.Strings(ks)
for _, k := range ks {
v := m.OutputValues[k]
lv := hcl2shim.ConfigValueFromHCL2(v.Value)
switch vTyped := lv.(type) {
case string:
buf.WriteString(fmt.Sprintf("%s = %s\n", k, vTyped))
case []interface{}:
buf.WriteString(fmt.Sprintf("%s = %s\n", k, vTyped))
case map[string]interface{}:
var mapKeys []string
for key := range vTyped {
mapKeys = append(mapKeys, key)
}
sort.Strings(mapKeys)
var mapBuf bytes.Buffer
mapBuf.WriteString("{")
for _, key := range mapKeys {
mapBuf.WriteString(fmt.Sprintf("%s:%s ", key, vTyped[key]))
}
mapBuf.WriteString("}")
buf.WriteString(fmt.Sprintf("%s = %s\n", k, mapBuf.String()))
}
}
}
return buf.String()
}
// legacyInstanceObjectID is a helper for extracting an object id value from
// an instance object in a way that approximates how we used to do this
// for the old state types. ID is no longer first-class, so this is preserved
// only for compatibility with old tests that include the id as part of their
// expected value.
func legacyInstanceObjectID(obj *ResourceInstanceObjectSrc) string {
if obj == nil {
return "<not created>"
}
if obj.AttrsJSON != nil {
type WithID struct {
ID string `json:"id"`
}
var withID WithID
err := json.Unmarshal(obj.AttrsJSON, &withID)
if err == nil {
return withID.ID
}
} else if obj.AttrsFlat != nil {
if flatID, exists := obj.AttrsFlat["id"]; exists {
return flatID
}
}
// For resource types created after we removed id as special there may
// not actually be one at all. This is okay because older tests won't
// encounter this, and new tests shouldn't be using ids.
return "<none>"
}