core: [refactor] DRY up EvalWriteState nodes

Also some final comment cleanup
This commit is contained in:
Paul Hinze 2015-03-04 18:01:46 -06:00
parent 6c93fbb85d
commit 6e13aacefa
3 changed files with 68 additions and 82 deletions

View File

@ -22,9 +22,7 @@ func (n *EvalReadState) Eval(ctx EvalContext) (interface{}, error) {
type EvalReadStateTainted struct {
Name string
Output **InstanceState
// Tainted is a per-resource list, this index determines which item in the
// list we are addressing
// Index indicates which instance in the Tainted list to target, or -1 for the last item.
Index int
}
@ -48,7 +46,8 @@ func (n *EvalReadStateTainted) Eval(ctx EvalContext) (interface{}, error) {
type EvalReadStateDeposed struct {
Name string
Output **InstanceState
Index int
// Index indicates which instance in the Deposed list to target, or -1 for the last item.
Index int
}
func (n *EvalReadStateDeposed) Eval(ctx EvalContext) (interface{}, error) {
@ -67,13 +66,13 @@ func (n *EvalReadStateDeposed) Eval(ctx EvalContext) (interface{}, error) {
}
// Does the bulk of the work for the various flavors of ReadState eval nodes.
// Each node just provides a function to get from the ResourceState to the
// Each node just provides a reader function to get from the ResourceState to the
// InstanceState, and this takes care of all the plumbing.
func readInstanceFromState(
ctx EvalContext,
resourceName string,
output **InstanceState,
f func(*ResourceState) (*InstanceState, error),
reader func(*ResourceState) (*InstanceState, error),
) (*InstanceState, error) {
state, lock := ctx.State()
@ -94,7 +93,7 @@ func readInstanceFromState(
}
// Use the delegate function to get the instance state from the resource state
is, err := f(rs)
is, err := reader(rs)
if err != nil {
return nil, err
}
@ -148,8 +147,8 @@ func (n *EvalUpdateStateHook) Eval(ctx EvalContext) (interface{}, error) {
return nil, nil
}
// EvalWriteState is an EvalNode implementation that reads the
// InstanceState for a specific resource out of the state.
// EvalWriteState is an EvalNode implementation that writes the
// primary InstanceState for a specific resource into the state.
type EvalWriteState struct {
Name string
ResourceType string
@ -158,88 +157,75 @@ type EvalWriteState struct {
}
func (n *EvalWriteState) Eval(ctx EvalContext) (interface{}, error) {
state, lock := ctx.State()
if state == nil {
return nil, fmt.Errorf("cannot write state to nil state")
}
// Get a write lock so we can access this instance
lock.Lock()
defer lock.Unlock()
// Look for the module state. If we don't have one, create it.
mod := state.ModuleByPath(ctx.Path())
if mod == nil {
mod = state.AddModule(ctx.Path())
}
// Look for the resource state.
rs := mod.Resources[n.Name]
if rs == nil {
rs = &ResourceState{}
rs.init()
mod.Resources[n.Name] = rs
}
rs.Type = n.ResourceType
rs.Dependencies = n.Dependencies
rs.Primary = *n.State
return nil, nil
return writeInstanceToState(ctx, n.Name, n.ResourceType, n.Dependencies,
func(rs *ResourceState) error {
rs.Primary = *n.State
return nil
},
)
}
// EvalWriteStateTainted is an EvalNode implementation that writes
// an InstanceState out to the Tainted list of a resource in the state.
type EvalWriteStateTainted struct {
Name string
ResourceType string
Dependencies []string
State **InstanceState
Index int
// Index indicates which instance in the Tainted list to target, or -1 to append.
Index int
}
// EvalWriteStateTainted is an EvalNode implementation that writes the
// one of the tainted InstanceStates for a specific resource out of the state.
func (n *EvalWriteStateTainted) Eval(ctx EvalContext) (interface{}, error) {
state, lock := ctx.State()
if state == nil {
return nil, fmt.Errorf("cannot write state to nil state")
}
// Get a write lock so we can access this instance
lock.Lock()
defer lock.Unlock()
// Look for the module state. If we don't have one, create it.
mod := state.ModuleByPath(ctx.Path())
if mod == nil {
mod = state.AddModule(ctx.Path())
}
// Look for the resource state.
rs := mod.Resources[n.Name]
if rs == nil {
rs = &ResourceState{}
rs.init()
mod.Resources[n.Name] = rs
}
rs.Type = n.ResourceType
rs.Dependencies = n.Dependencies
if n.Index == -1 {
rs.Tainted = append(rs.Tainted, *n.State)
} else {
rs.Tainted[n.Index] = *n.State
}
return nil, nil
return writeInstanceToState(ctx, n.Name, n.ResourceType, n.Dependencies,
func(rs *ResourceState) error {
if n.Index == -1 {
rs.Tainted = append(rs.Tainted, *n.State)
} else {
rs.Tainted[n.Index] = *n.State
}
return nil
},
)
}
// EvalWriteStateDeposed is an EvalNode implementation that writes
// an InstanceState out to the Deposed list of a resource in the state.
type EvalWriteStateDeposed struct {
Name string
ResourceType string
Dependencies []string
State **InstanceState
Index int
// Index indicates which instance in the Deposed list to target, or -1 to append.
Index int
}
func (n *EvalWriteStateDeposed) Eval(ctx EvalContext) (interface{}, error) {
return writeInstanceToState(ctx, n.Name, n.ResourceType, n.Dependencies,
func(rs *ResourceState) error {
if n.Index == -1 {
rs.Deposed = append(rs.Deposed, *n.State)
} else {
rs.Deposed[n.Index] = *n.State
}
return nil
},
)
}
// Pulls together the common tasks of the EvalWriteState nodes. All the args
// are passed directly down from the EvalNode along with a `writer` function
// which is yielded the *ResourceState and is responsible for writing an
// InstanceState to the proper field in the ResourceState.
func writeInstanceToState(
ctx EvalContext,
resourceName string,
resourceType string,
dependencies []string,
writer func(*ResourceState) error,
) (*InstanceState, error) {
state, lock := ctx.State()
if state == nil {
return nil, fmt.Errorf("cannot write state to nil state")
@ -256,19 +242,17 @@ func (n *EvalWriteStateDeposed) Eval(ctx EvalContext) (interface{}, error) {
}
// Look for the resource state.
rs := mod.Resources[n.Name]
rs := mod.Resources[resourceName]
if rs == nil {
rs = &ResourceState{}
rs.init()
mod.Resources[n.Name] = rs
mod.Resources[resourceName] = rs
}
rs.Type = n.ResourceType
rs.Dependencies = n.Dependencies
rs.Type = resourceType
rs.Dependencies = dependencies
if n.Index == -1 {
rs.Deposed = append(rs.Deposed, *n.State)
} else {
rs.Deposed[n.Index] = *n.State
if err := writer(rs); err != nil {
return nil, err
}
return nil, nil

View File

@ -658,8 +658,10 @@ type ResourceState struct {
// Primary is Deposed to get it out of the way for the replacement Primary to
// be created by Apply. If the replacement Primary creates successfully, the
// Deposed instance is cleaned up. If there were problems creating the
// replacement, we mark the replacement as Tainted and Undepose the former
// Primary.
// replacement, the instance remains in the Deposed list so it can be
// destroyed in a future run. Functionally, Deposed instances are very
// similar to Tainted instances in that Terraform is only tracking them in
// order to remember to destroy them.
Deposed []*InstanceState `json:"deposed,omitempty"`
}

View File

@ -2,7 +2,7 @@ package terraform
import "fmt"
// DeposedTransformer is a GraphTransformer that adds tainted resources
// DeposedTransformer is a GraphTransformer that adds deposed resources
// to the graph.
type DeposedTransformer struct {
// State is the global state. We'll automatically find the correct