Set PLANFILE environment variable in run step.

Env var is set to where Atlantis expects the planfile to be.
Fixes #168.

runatlantis.io/docs/atlantis-yaml-reference.md

@@ -138,7 +138,7 @@ steps:
 | steps      | array[[Step](atlantis-yaml-reference.html#step)] | `[]` | no | List of steps for this stage. If the steps key is empty, no steps will be run for this stage. |
 
 ### Step
-#### Built-In Command
+#### Built-In Commands: init, plan, apply
 Steps can be a single string for a built-in command.
 ```yaml
 - init
@@ -162,7 +162,7 @@ A map from string to `extra_args` for a built-in command with extra arguments.
 | Key        | Type | Default           | Required | Description  |
 | -------------| --- |-------------| -----|---|
 | init/plan/apply      | map[`extra_args` -> array[string]] | none | no | Use a built-in command and append `extra_args`. Only `init`, `plan` and `apply` are supported as keys and only `extra_args` is supported as a value||
-#### Custom Command
+#### Custom `run` Command
 Or a custom command
 ```yaml
 - run: custom-command
@@ -177,6 +177,9 @@ Or a custom command
   * NOTE: if the step is executed before `init` then Atlantis won't have switched to this workspace yet.
 * `ATLANTIS_TERRAFORM_VERSION` - The version of Terraform used for this project, ex. `0.11.0`.
 * `DIR` - Absolute path to the current directory.
+* `PLANFILE` - Absolute path to the location where Atlantis expects the plan to
+either be generated (by plan) or already exist (if running apply). Can be used to
+override the built-in `plan`/`apply` commands, ex. `run: terraform plan -out $PLANFILE`.
 :::
 
 ## Next Steps

server/events/runtime/apply_step_runner.go

@@ -15,18 +15,13 @@ type ApplyStepRunner struct {
 }
 
 func (a *ApplyStepRunner) Run(ctx models.ProjectCommandContext, extraArgs []string, path string) (string, error) {
-	// todo: move this to a common library
-	planFileName := fmt.Sprintf("%s.tfplan", ctx.Workspace)
-	if ctx.ProjectConfig != nil && ctx.ProjectConfig.Name != nil {
-		planFileName = fmt.Sprintf("%s-%s", *ctx.ProjectConfig.Name, planFileName)
-	}
-	planFile := filepath.Join(path, planFileName)
-	stat, err := os.Stat(planFile)
+	planPath := filepath.Join(path, GetPlanFilename(ctx.Workspace, ctx.ProjectConfig))
+	stat, err := os.Stat(planPath)
 	if err != nil || stat.IsDir() {
 		return "", fmt.Errorf("no plan found at path %q and workspace %q–did you run plan?", ctx.RepoRelDir, ctx.Workspace)
 	}
 
-	tfApplyCmd := append(append(append([]string{"apply", "-no-color"}, extraArgs...), ctx.CommentArgs...), planFile)
+	tfApplyCmd := append(append(append([]string{"apply", "-no-color"}, extraArgs...), ctx.CommentArgs...), planPath)
 	var tfVersion *version.Version
 	if ctx.ProjectConfig != nil && ctx.ProjectConfig.TerraformVersion != nil {
 		tfVersion = ctx.ProjectConfig.TerraformVersion

server/events/runtime/plan_step_runner.go

@@ -32,12 +32,7 @@ func (p *PlanStepRunner) Run(ctx models.ProjectCommandContext, extraArgs []strin
 		return "", err
 	}
 
-	// todo: move this to a common library
-	planFileName := fmt.Sprintf("%s.tfplan", ctx.Workspace)
-	if ctx.ProjectConfig != nil && ctx.ProjectConfig.Name != nil {
-		planFileName = fmt.Sprintf("%s-%s", *ctx.ProjectConfig.Name, planFileName)
-	}
-	planFile := filepath.Join(path, planFileName)
+	planFile := filepath.Join(path, GetPlanFilename(ctx.Workspace, ctx.ProjectConfig))
 	userVar := fmt.Sprintf("%s=%s", atlantisUserTFVar, ctx.User.Username)
 	tfPlanCmd := append(append([]string{"plan", "-refresh", "-no-color", "-out", planFile, "-var", userVar}, extraArgs...), ctx.CommentArgs...)
 

server/events/runtime/run_step_runner.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strings"
 
 	"github.com/hashicorp/go-version"
@@ -32,6 +33,7 @@ func (r *RunStepRunner) Run(ctx models.ProjectCommandContext, command []string,
 		fmt.Sprintf("WORKSPACE=%s", ctx.Workspace),
 		fmt.Sprintf("ATLANTIS_TERRAFORM_VERSION=%s", tfVersion),
 		fmt.Sprintf("DIR=%s", path),
+		fmt.Sprintf("PLANFILE=%s", filepath.Join(path, GetPlanFilename(ctx.Workspace, ctx.ProjectConfig))),
 	}
 	finalEnvVars := append(baseEnvVars, customEnvVars...)
 	cmd.Env = finalEnvVars

server/events/runtime/run_step_runner_test.go

@@ -35,8 +35,8 @@ func TestRunStepRunner_Run(t *testing.T) {
 			ExpErr:  "exit status 127: running \"lkjlkj\" in",
 		},
 		{
-			Command: "echo workspace=$WORKSPACE version=$ATLANTIS_TERRAFORM_VERSION dir=$DIR",
-			ExpOut:  "workspace=myworkspace version=0.11.0 dir=$DIR\n",
+			Command: "echo workspace=$WORKSPACE version=$ATLANTIS_TERRAFORM_VERSION dir=$DIR planfile=$PLANFILE",
+			ExpOut:  "workspace=myworkspace version=0.11.0 dir=$DIR planfile=$DIR/myworkspace.tfplan\n",
 		},
 	}
 
@@ -70,7 +70,10 @@ func TestRunStepRunner_Run(t *testing.T) {
 				return
 			}
 			Ok(t, err)
-			expOut := strings.Replace(c.ExpOut, "dir=$DIR", "dir="+tmpDir, -1)
+			// Replace $DIR in the exp with the actual temp dir. We do this
+			// here because when constructing the cases we don't yet know the
+			// temp dir.
+			expOut := strings.Replace(c.ExpOut, "$DIR", tmpDir, -1)
 			Equals(t, expOut, out)
 		})
 	}

server/events/runtime/runtime.go

@@ -1,10 +1,12 @@
-// Package runtime handles constructing an execution graph for each action
-// based on configuration and defaults. The handlers can then execute this
-// graph.
+// Package runtime holds code for actually running commands vs. preparing
+// and constructing.
 package runtime
 
 import (
+	"fmt"
+
 	"github.com/hashicorp/go-version"
+	"github.com/runatlantis/atlantis/server/events/yaml/valid"
 	"github.com/runatlantis/atlantis/server/logging"
 )
 
@@ -20,3 +22,12 @@ func MustConstraint(constraint string) version.Constraints {
 	}
 	return c
 }
+
+// GetPlanFilename returns the filename (not the path) of the generated tf plan
+// given a workspace and maybe a project's config.
+func GetPlanFilename(workspace string, maybeCfg *valid.Project) string {
+	if maybeCfg == nil || maybeCfg.Name == nil {
+		return fmt.Sprintf("%s.tfplan", workspace)
+	}
+	return fmt.Sprintf("%s-%s.tfplan", *maybeCfg.Name, workspace)
+}

server/events/runtime/runtime_test.go

@@ -0,0 +1,44 @@
+package runtime_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/runatlantis/atlantis/server/events/runtime"
+	"github.com/runatlantis/atlantis/server/events/yaml/valid"
+	. "github.com/runatlantis/atlantis/testing"
+)
+
+func TestGetPlanFilename(t *testing.T) {
+	cases := []struct {
+		workspace string
+		maybeCfg  *valid.Project
+		exp       string
+	}{
+		{
+			"workspace",
+			nil,
+			"workspace.tfplan",
+		},
+		{
+			"workspace",
+			&valid.Project{},
+			"workspace.tfplan",
+		},
+		{
+			"workspace",
+			&valid.Project{
+				Name: String("project"),
+			},
+			"project-workspace.tfplan",
+		},
+	}
+
+	for i, c := range cases {
+		t.Run(fmt.Sprintf("case %d", i), func(t *testing.T) {
+			Equals(t, c.exp, runtime.GetPlanFilename(c.workspace, c.maybeCfg))
+		})
+	}
+}
+
+func String(v string) *string { return &v }