terraform/terraform/semantics.go

115 lines
2.7 KiB
Go

package terraform
import (
"fmt"
"github.com/hashicorp/go-multierror"
"github.com/hashicorp/terraform/config"
"github.com/hashicorp/terraform/dag"
)
// GraphSemanticChecker is the interface that semantic checks across
// the entire Terraform graph implement.
//
// The graph should NOT be modified by the semantic checker.
type GraphSemanticChecker interface {
Check(*dag.Graph) error
}
// UnorderedSemanticCheckRunner is an implementation of GraphSemanticChecker
// that runs a list of SemanticCheckers against the vertices of the graph
// in no specified order.
type UnorderedSemanticCheckRunner struct {
Checks []SemanticChecker
}
func (sc *UnorderedSemanticCheckRunner) Check(g *dag.Graph) error {
var err error
for _, v := range g.Vertices() {
for _, check := range sc.Checks {
if e := check.Check(g, v); e != nil {
err = multierror.Append(err, e)
}
}
}
return err
}
// SemanticChecker is the interface that semantic checks across the
// Terraform graph implement. Errors are accumulated. Even after an error
// is returned, child vertices in the graph will still be visited.
//
// The graph should NOT be modified by the semantic checker.
//
// The order in which vertices are visited is left unspecified, so the
// semantic checks should not rely on that.
type SemanticChecker interface {
Check(*dag.Graph, dag.Vertex) error
}
// SemanticCheckModulesExist is an implementation of SemanticChecker that
// verifies that all the modules that are referenced in the graph exist.
type SemanticCheckModulesExist struct{}
// TODO: test
func (*SemanticCheckModulesExist) Check(g *dag.Graph, v dag.Vertex) error {
mn, ok := v.(*GraphNodeConfigModule)
if !ok {
return nil
}
if mn.Tree == nil {
return fmt.Errorf(
"module '%s' not found", mn.Module.Name)
}
return nil
}
// smcUserVariables does all the semantic checks to verify that the
// variables given satisfy the configuration itself.
func smcUserVariables(c *config.Config, vs map[string]string) []error {
var errs []error
cvs := make(map[string]*config.Variable)
for _, v := range c.Variables {
cvs[v.Name] = v
}
// Check that all required variables are present
required := make(map[string]struct{})
for _, v := range c.Variables {
if v.Required() {
required[v.Name] = struct{}{}
}
}
for k, _ := range vs {
delete(required, k)
}
if len(required) > 0 {
for k, _ := range required {
errs = append(errs, fmt.Errorf(
"Required variable not set: %s", k))
}
}
// Check that types match up
for k, _ := range vs {
v, ok := cvs[k]
if !ok {
continue
}
if v.Type() != config.VariableTypeString {
errs = append(errs, fmt.Errorf(
"%s: cannot assign string value to map type",
k))
}
}
// TODO(mitchellh): variables that are unknown
return errs
}