Version detection using terraform-config-inspect

server/events/project_command_builder.go

@@ -1,11 +1,15 @@
 package events
 
 import (
+	"regexp"
+	"path/filepath"
 	"fmt"
 	"strings"
 
 	"github.com/runatlantis/atlantis/server/events/yaml/valid"
 
+	"github.com/hashicorp/go-version"
+	"github.com/hashicorp/terraform-config-inspect/tfconfig"
 	"github.com/pkg/errors"
 	"github.com/runatlantis/atlantis/server/events/models"
 	"github.com/runatlantis/atlantis/server/events/vcs"
@@ -137,7 +141,7 @@ func (p *DefaultProjectCommandBuilder) buildPlanAllCommands(ctx *CommandContext,
 		for _, mp := range matchingProjects {
 			ctx.Log.Debug("determining config for project at dir: %q workspace: %q", mp.Dir, mp.Workspace)
 			mergedCfg := p.GlobalCfg.MergeProjectCfg(ctx.Log, ctx.BaseRepo.ID(), mp, repoCfg)
-			projCtxs = append(projCtxs, p.buildCtx(ctx, models.PlanCommand, mergedCfg, commentFlags, repoCfg.Automerge, verbose))
+			projCtxs = append(projCtxs, p.buildCtx(ctx, models.PlanCommand, mergedCfg, commentFlags, repoCfg.Automerge, verbose, repoDir))
 		}
 	} else {
 		// If there is no config file, then we'll plan each project that
@@ -148,7 +152,7 @@ func (p *DefaultProjectCommandBuilder) buildPlanAllCommands(ctx *CommandContext,
 		for _, mp := range modifiedProjects {
 			ctx.Log.Debug("determining config for project at dir: %q", mp.Path)
 			pCfg := p.GlobalCfg.DefaultProjCfg(ctx.Log, ctx.BaseRepo.ID(), mp.Path, DefaultWorkspace)
-			projCtxs = append(projCtxs, p.buildCtx(ctx, models.PlanCommand, pCfg, commentFlags, DefaultAutomergeEnabled, verbose))
+			projCtxs = append(projCtxs, p.buildCtx(ctx, models.PlanCommand, pCfg, commentFlags, DefaultAutomergeEnabled, verbose, repoDir))
 		}
 	}
 
@@ -282,7 +286,7 @@ func (p *DefaultProjectCommandBuilder) buildProjectCommandCtx(
 	if repoCfgPtr != nil {
 		automerge = repoCfgPtr.Automerge
 	}
-	return p.buildCtx(ctx, cmd, projCfg, commentFlags, automerge, verbose), nil
+	return p.buildCtx(ctx, cmd, projCfg, commentFlags, automerge, verbose, repoDir), nil
 }
 
 // getCfg returns the atlantis.yaml config (if it exists) for this project. If
@@ -371,7 +375,8 @@ func (p *DefaultProjectCommandBuilder) buildCtx(ctx *CommandContext,
 	projCfg valid.MergedProjectCfg,
 	commentArgs []string,
 	automergeEnabled bool,
-	verbose bool) models.ProjectCommandContext {
+	verbose bool,
+	absRepoDir string) models.ProjectCommandContext {
 
 	var steps []valid.Step
 	switch cmd {
@@ -381,6 +386,17 @@ func (p *DefaultProjectCommandBuilder) buildCtx(ctx *CommandContext,
 		steps = projCfg.Workflow.Apply.Steps
 	}
 
+	// if TerraformVersion not defined in config file fallback to terraform configuration
+	if projCfg.TerraformVersion == nil {
+		version, err := p.getTfVersion(filepath.Join(absRepoDir, projCfg.RepoRelDir))
+		if err != nil {
+			fmt.Println(err.Error())
+			ctx.Log.Debug(err.Error())
+		} else {
+			projCfg.TerraformVersion = version
+		}
+	}
+
 	return models.ProjectCommandContext{
 		ApplyCmd:           p.CommentBuilder.BuildApplyComment(projCfg.RepoRelDir, projCfg.Workspace, projCfg.Name),
 		BaseRepo:           ctx.BaseRepo,
@@ -415,3 +431,19 @@ func (p *DefaultProjectCommandBuilder) escapeArgs(args []string) []string {
 	}
 	return escaped
 }
+
+// Extracts required_version from Terraform configuration
+func (p *DefaultProjectCommandBuilder) getTfVersion(absProjDir string) (*version.Version, error) {
+	module, diags := tfconfig.LoadModule(absProjDir)
+	if diags.HasErrors() {
+		return nil, diags.Err()
+	}
+	if len(module.RequiredCore) == 1 {
+		re := regexp.MustCompile(`^=?\s*([^\s]+)\s*$`)
+		if matched := re.FindStringSubmatch(module.RequiredCore[0]); len(matched) > 0 {
+			return version.NewVersion(matched[1])
+		}
+		return nil, errors.Errorf("did not specify exact version in terraform configuration.")
+	}
+	return nil, errors.Errorf("cannot determine required core from terraform configuration.")
+}

server/events/project_command_builder_test.go

@@ -5,7 +5,6 @@ import (
 	"path/filepath"
 	"strings"
 	"testing"
-	"fmt"
 
 	. "github.com/petergtz/pegomock"
 	"github.com/runatlantis/atlantis/server/events"
@@ -726,8 +725,11 @@ projects:
 - dir: project1 # project1 uses the defaults
   terraform_version: v0.12.6
 `
-	versionConfig := fmt.Sprintf("terraform { required_version = \"= %s\"}", "0.12.8")
-
+	versionConfig := `
+terraform {
+  required_version = "= 0.12.8"
+}	  
+`
 	testCases := map[string]struct {
 		DirStructure  map[string]interface{}
 		AtlantisYAML  string
@@ -737,7 +739,7 @@ projects:
 		"no atlantis.yaml": {
 			DirStructure: map[string]interface{}{
 				"project1": map[string]interface{}{
-					"main.tf": nil,
+					"main.tf":    nil,
 					"version.tf": versionConfig,
 				},
 			},
@@ -746,11 +748,12 @@ projects:
 				"TerraformVersion": []int{0, 12, 8},
 			},
 		},
+		// atlantis.yaml should take precedence over terraform config
 		"defined in atlantis.yaml": {
 			DirStructure: map[string]interface{}{
 				"project1": map[string]interface{}{
-					"main.tf": nil,
-					"version.tf":  versionConfig,
+					"main.tf":    nil,
+					"version.tf": versionConfig,
 				},
 				yaml.AtlantisYAMLFilename: atlantisYamlContent,
 			},
@@ -762,24 +765,24 @@ projects:
 	}
 
 	for name, testCase := range testCases {
-		t.Run(name, func (t *testing.T) {
+		t.Run(name, func(t *testing.T) {
 			RegisterMockTestingT(t)
-			
+
 			tmpDir, cleanup := DirStructure(t, testCase.DirStructure)
 
 			defer cleanup()
 
 			workingDir := mocks.NewMockWorkingDir()
 			When(workingDir.Clone(
-				matchers.AnyPtrToLoggingSimpleLogger(), 
-				matchers.AnyModelsRepo(), 
-				matchers.AnyModelsRepo(), 
-				matchers.AnyModelsPullRequest(), 
+				matchers.AnyPtrToLoggingSimpleLogger(),
+				matchers.AnyModelsRepo(),
+				matchers.AnyModelsRepo(),
+				matchers.AnyModelsPullRequest(),
 				AnyString())).ThenReturn(tmpDir, nil)
-		
+
 			When(workingDir.GetWorkingDir(
-				matchers.AnyModelsRepo(), 
-				matchers.AnyModelsPullRequest(), 
+				matchers.AnyModelsRepo(),
+				matchers.AnyModelsPullRequest(),
 				AnyString())).ThenReturn(tmpDir, nil)
 
 			builder := &events.DefaultProjectCommandBuilder{
@@ -791,14 +794,12 @@ projects:
 				GlobalCfg:        valid.NewGlobalCfg(true, false, false),
 			}
 
-			var actCtxs []models.ProjectCommandContext
-			var err error
-			actCtxs, err = builder.BuildPlanCommands(&events.CommandContext{}, &events.CommentCommand{
+			actCtxs, err := builder.BuildPlanCommands(&events.CommandContext{}, &events.CommentCommand{
 				RepoRelDir: "project1",
 				Name:       models.PlanCommand,
 				Verbose:    false,
 			})
-			
+
 			Ok(t, err)
 			Equals(t, 1, len(actCtxs))
 			actCtx := actCtxs[0]