Merge pull request #26190 from hashicorp/pselle/force-push-fix

Fix bug for force push for backends besides the remote backend
This commit is contained in:
Pam Selle 2020-09-10 09:20:07 -04:00 committed by GitHub
commit ee544aa4e8
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3 changed files with 215 additions and 21 deletions

View File

@ -69,7 +69,6 @@ func (c nilClient) Delete() error { return nil }
type mockClient struct {
current []byte
log []mockClientRequest
force bool
}
type mockClientRequest struct {
@ -90,11 +89,7 @@ func (c *mockClient) Get() (*Payload, error) {
}
func (c *mockClient) Put(data []byte) error {
if c.force {
c.appendLog("Force Put", data)
} else {
c.appendLog("Put", data)
}
c.current = data
return nil
}
@ -105,11 +100,6 @@ func (c *mockClient) Delete() error {
return nil
}
// Implements remote.ClientForcePusher
func (c *mockClient) EnableForcePush() {
c.force = true
}
func (c *mockClient) appendLog(method string, content []byte) {
// For easier test assertions, we actually log the result of decoding
// the content JSON rather than the raw bytes. Callers are in principle
@ -126,3 +116,54 @@ func (c *mockClient) appendLog(method string, content []byte) {
}
c.log = append(c.log, mockClientRequest{method, contentVal})
}
// mockClientForcePusher is like mockClient, but also implements
// EnableForcePush, allowing testing for this behavior
type mockClientForcePusher struct {
current []byte
force bool
log []mockClientRequest
}
func (c *mockClientForcePusher) Get() (*Payload, error) {
c.appendLog("Get", c.current)
if c.current == nil {
return nil, nil
}
checksum := md5.Sum(c.current)
return &Payload{
Data: c.current,
MD5: checksum[:],
}, nil
}
func (c *mockClientForcePusher) Put(data []byte) error {
if c.force {
c.appendLog("Force Put", data)
} else {
c.appendLog("Put", data)
}
c.current = data
return nil
}
// Implements remote.ClientForcePusher
func (c *mockClientForcePusher) EnableForcePush() {
c.force = true
}
func (c *mockClientForcePusher) Delete() error {
c.appendLog("Delete", c.current)
c.current = nil
return nil
}
func (c *mockClientForcePusher) appendLog(method string, content []byte) {
var contentVal map[string]interface{}
if content != nil {
err := json.Unmarshal(content, &contentVal)
if err != nil {
panic(err) // should never happen because our tests control this input
}
}
c.log = append(c.log, mockClientRequest{method, contentVal})
}

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@ -72,20 +72,21 @@ func (s *State) WriteStateForMigration(f *statefile.File, force bool) error {
s.mu.Lock()
defer s.mu.Unlock()
// `force` is passed down from the CLI flag and terminates here. Actual
// force pushing with the remote backend happens when Put()'ing the contents
// in the backend. If force is specified we skip verifications and hand the
// context off to the client to use when persitence operations actually take place.
c, isForcePusher := s.Client.(ClientForcePusher)
if force && isForcePusher {
c.EnableForcePush()
} else {
if !force {
checkFile := statefile.New(s.state, s.lineage, s.serial)
if err := statemgr.CheckValidImport(f, checkFile); err != nil {
return err
}
}
// The remote backend needs to pass the `force` flag through to its client.
// For backends that support such operations, inform the client
// that a force push has been requested
c, isForcePusher := s.Client.(ClientForcePusher)
if force && isForcePusher {
c.EnableForcePush()
}
// We create a deep copy of the state here, because the caller also has
// a reference to the given object and can potentially go on to mutate
// it after we return, but we want the snapshot at this point in time.

View File

@ -302,6 +302,158 @@ func TestWriteStateForMigration(t *testing.T) {
},
}
testCases := []migrationTestCase{
// Refreshing state before we run the test loop causes a GET
{
name: "refresh state",
stateFile: func(mgr *State) *statefile.File {
return mgr.StateForMigration()
},
expectedRequest: mockClientRequest{
Method: "Get",
Content: map[string]interface{}{
"version": 4.0,
"lineage": "mock-lineage",
"serial": 3.0,
"terraform_version": "0.0.0",
"outputs": map[string]interface{}{"foo": map[string]interface{}{"type": string("string"), "value": string("bar")}},
"resources": []interface{}{},
},
},
},
{
name: "cannot import lesser serial without force",
stateFile: func(mgr *State) *statefile.File {
return statefile.New(mgr.state, mgr.lineage, 1)
},
expectedError: "cannot import state with serial 1 over newer state with serial 3",
},
{
name: "cannot import differing lineage without force",
stateFile: func(mgr *State) *statefile.File {
return statefile.New(mgr.state, "different-lineage", mgr.serial)
},
expectedError: `cannot import state with lineage "different-lineage" over unrelated state with lineage "mock-lineage"`,
},
{
name: "can import lesser serial with force",
stateFile: func(mgr *State) *statefile.File {
return statefile.New(mgr.state, mgr.lineage, 1)
},
expectedRequest: mockClientRequest{
Method: "Put",
Content: map[string]interface{}{
"version": 4.0,
"lineage": "mock-lineage",
"serial": 2.0,
"terraform_version": version.Version,
"outputs": map[string]interface{}{"foo": map[string]interface{}{"type": string("string"), "value": string("bar")}},
"resources": []interface{}{},
},
},
force: true,
},
{
name: "cannot import differing lineage without force",
stateFile: func(mgr *State) *statefile.File {
return statefile.New(mgr.state, "different-lineage", mgr.serial)
},
expectedRequest: mockClientRequest{
Method: "Put",
Content: map[string]interface{}{
"version": 4.0,
"lineage": "different-lineage",
"serial": 3.0,
"terraform_version": version.Version,
"outputs": map[string]interface{}{"foo": map[string]interface{}{"type": string("string"), "value": string("bar")}},
"resources": []interface{}{},
},
},
force: true,
},
}
// In normal use (during a Terraform operation) we always refresh and read
// before any writes would happen, so we'll mimic that here for realism.
// NB This causes a GET to be logged so the first item in the test cases
// must account for this
if err := mgr.RefreshState(); err != nil {
t.Fatalf("failed to RefreshState: %s", err)
}
if err := mgr.WriteState(mgr.State()); err != nil {
t.Fatalf("failed to write initial state: %s", err)
}
// Our client is a mockClient which has a log we
// use to check that operations generate expected requests
mockClient := mgr.Client.(*mockClient)
// logIdx tracks the current index of the log separate from
// the loop iteration so we can check operations that don't
// cause any requests to be generated
logIdx := 0
for _, tc := range testCases {
sf := tc.stateFile(mgr)
err := mgr.WriteStateForMigration(sf, tc.force)
shouldError := tc.expectedError != ""
// If we are expecting and error check it and move on
if shouldError {
if err == nil {
t.Fatalf("test case %q should have failed with error %q", tc.name, tc.expectedError)
} else if err.Error() != tc.expectedError {
t.Fatalf("test case %q expected error %q but got %q", tc.name, tc.expectedError, err)
}
continue
}
if err != nil {
t.Fatalf("test case %q failed: %v", tc.name, err)
}
// At this point we should just do a normal write and persist
// as would happen from the CLI
mgr.WriteState(mgr.State())
mgr.PersistState()
if logIdx >= len(mockClient.log) {
t.Fatalf("request lock and index are out of sync on %q: idx=%d len=%d", tc.name, logIdx, len(mockClient.log))
}
loggedRequest := mockClient.log[logIdx]
logIdx++
if diff := cmp.Diff(tc.expectedRequest, loggedRequest); len(diff) > 0 {
t.Fatalf("incorrect client requests for %q:\n%s", tc.name, diff)
}
}
logCnt := len(mockClient.log)
if logIdx != logCnt {
log.Fatalf("not all requests were read. Expected logIdx to be %d but got %d", logCnt, logIdx)
}
}
// This test runs the same test cases as above, but with
// a client that implements EnableForcePush -- this allows
// us to test that -force continues to work for backends without
// this interface, but that this interface works for those that do.
func TestWriteStateForMigrationWithForcePushClient(t *testing.T) {
mgr := &State{
Client: &mockClientForcePusher{
current: []byte(`
{
"version": 4,
"lineage": "mock-lineage",
"serial": 3,
"terraform_version":"0.0.0",
"outputs": {"foo": {"value":"bar", "type": "string"}},
"resources": []
}
`),
},
}
testCases := []migrationTestCase{
// Refreshing state before we run the test loop causes a GET
{
@ -385,9 +537,9 @@ func TestWriteStateForMigration(t *testing.T) {
t.Fatalf("failed to write initial state: %s", err)
}
// Our client is a mockClient which has a log we
// Our client is a mockClientForcePusher which has a log we
// use to check that operations generate expected requests
mockClient := mgr.Client.(*mockClient)
mockClient := mgr.Client.(*mockClientForcePusher)
if mockClient.force {
t.Fatalf("client should not default to force")