terraform/terraform/semantics.go

133 lines
3.4 KiB
Go

package terraform
import (
"fmt"
"strings"
"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
}
// smcUserVariables does all the semantic checks to verify that the
// variables given satisfy the configuration itself.
func smcUserVariables(c *config.Config, vs map[string]interface{}) []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 name, proposedValue := range vs {
// Check for "map.key" fields. These stopped working with Terraform
// 0.7 but we do this to surface a better error message informing
// the user what happened.
if idx := strings.Index(name, "."); idx > 0 {
key := name[:idx]
if _, ok := cvs[key]; ok {
errs = append(errs, fmt.Errorf(
"%s: Overriding map keys with the format `name.key` is no "+
"longer allowed. You may still override keys by setting "+
"`name = { key = value }`. The maps will be merged. This "+
"behavior appeared in 0.7.0.", name))
continue
}
}
schema, ok := cvs[name]
if !ok {
continue
}
declaredType := schema.Type()
switch declaredType {
case config.VariableTypeString:
switch proposedValue.(type) {
case string:
continue
}
case config.VariableTypeMap:
switch v := proposedValue.(type) {
case map[string]interface{}:
continue
case []map[string]interface{}:
// if we have a list of 1 map, it will get coerced later as needed
if len(v) == 1 {
continue
}
}
case config.VariableTypeList:
switch proposedValue.(type) {
case []interface{}:
continue
}
}
errs = append(errs, fmt.Errorf("variable %s should be type %s, got %s",
name, declaredType.Printable(), hclTypeName(proposedValue)))
}
// TODO(mitchellh): variables that are unknown
return errs
}