opentofu/command/graph.go
Alisdair McDiarmid c5c1f31db3 backend: Validate remote backend Terraform version
When using the enhanced remote backend, a subset of all Terraform
operations are supported. Of these, only plan and apply can be executed
on the remote infrastructure (e.g. Terraform Cloud). Other operations
run locally and use the remote backend for state storage.

This causes problems when the local version of Terraform does not match
the configured version from the remote workspace. If the two versions
are incompatible, an `import` or `state mv` operation can cause the
remote workspace to be unusable until a manual fix is applied.

To prevent this from happening accidentally, this commit introduces a
check that the local Terraform version and the configured remote
workspace Terraform version are compatible. This check is skipped for
commands which do not write state, and can also be disabled by the use
of a new command-line flag, `-ignore-remote-version`.

Terraform version compatibility is defined as:

- For all releases before 0.14.0, local must exactly equal remote, as
  two different versions cannot share state;
- 0.14.0 to 1.0.x are compatible, as we will not change the state
  version number until at least Terraform 1.1.0;
- Versions after 1.1.0 must have the same major and minor versions, as
  we will not change the state version number in a patch release.

If the two versions are incompatible, a diagnostic is displayed,
advising that the error can be suppressed with `-ignore-remote-version`.
When this flag is used, the diagnostic is still displayed, but as a
warning instead of an error.

Commands which will not write state can assert this fact by calling the
helper `meta.ignoreRemoteBackendVersionConflict`, which will disable the
checks. Those which can write state should instead call the helper
`meta.remoteBackendVersionCheck`, which will return diagnostics for
display.

In addition to these explicit paths for managing the version check, we
have an implicit check in the remote backend's state manager
initialization method. Both of the above helpers will disable this
check. This fallback is in place to ensure that future code paths which
access state cannot accidentally skip the remote version check.
2020-11-19 13:19:40 -05:00

198 lines
5.0 KiB
Go

package command
import (
"fmt"
"strings"
"github.com/hashicorp/terraform/plans"
"github.com/hashicorp/terraform/tfdiags"
"github.com/hashicorp/terraform/backend"
"github.com/hashicorp/terraform/dag"
"github.com/hashicorp/terraform/terraform"
)
// GraphCommand is a Command implementation that takes a Terraform
// configuration and outputs the dependency tree in graphical form.
type GraphCommand struct {
Meta
}
func (c *GraphCommand) Run(args []string) int {
var drawCycles bool
var graphTypeStr string
var moduleDepth int
var verbose bool
args = c.Meta.process(args)
cmdFlags := c.Meta.defaultFlagSet("graph")
cmdFlags.BoolVar(&drawCycles, "draw-cycles", false, "draw-cycles")
cmdFlags.StringVar(&graphTypeStr, "type", "", "type")
cmdFlags.IntVar(&moduleDepth, "module-depth", -1, "module-depth")
cmdFlags.BoolVar(&verbose, "verbose", false, "verbose")
cmdFlags.Usage = func() { c.Ui.Error(c.Help()) }
if err := cmdFlags.Parse(args); err != nil {
c.Ui.Error(fmt.Sprintf("Error parsing command-line flags: %s\n", err.Error()))
return 1
}
configPath, err := ModulePath(cmdFlags.Args())
if err != nil {
c.Ui.Error(err.Error())
return 1
}
// Check for user-supplied plugin path
if c.pluginPath, err = c.loadPluginPath(); err != nil {
c.Ui.Error(fmt.Sprintf("Error loading plugin path: %s", err))
return 1
}
// Check if the path is a plan
var plan *plans.Plan
planFile, err := c.PlanFile(configPath)
if err != nil {
c.Ui.Error(err.Error())
return 1
}
if planFile != nil {
// Reset for backend loading
configPath = ""
}
var diags tfdiags.Diagnostics
backendConfig, backendDiags := c.loadBackendConfig(configPath)
diags = diags.Append(backendDiags)
if diags.HasErrors() {
c.showDiagnostics(diags)
return 1
}
// Load the backend
b, backendDiags := c.Backend(&BackendOpts{
Config: backendConfig,
})
diags = diags.Append(backendDiags)
if backendDiags.HasErrors() {
c.showDiagnostics(diags)
return 1
}
// We require a local backend
local, ok := b.(backend.Local)
if !ok {
c.showDiagnostics(diags) // in case of any warnings in here
c.Ui.Error(ErrUnsupportedLocalOp)
return 1
}
// This is a read-only command
c.ignoreRemoteBackendVersionConflict(b)
// Build the operation
opReq := c.Operation(b)
opReq.ConfigDir = configPath
opReq.ConfigLoader, err = c.initConfigLoader()
opReq.PlanFile = planFile
opReq.AllowUnsetVariables = true
if err != nil {
diags = diags.Append(err)
c.showDiagnostics(diags)
return 1
}
// Get the context
ctx, _, ctxDiags := local.Context(opReq)
diags = diags.Append(ctxDiags)
if ctxDiags.HasErrors() {
c.showDiagnostics(diags)
return 1
}
// Determine the graph type
graphType := terraform.GraphTypePlan
if plan != nil {
graphType = terraform.GraphTypeApply
}
if graphTypeStr != "" {
v, ok := terraform.GraphTypeMap[graphTypeStr]
if !ok {
c.Ui.Error(fmt.Sprintf("Invalid graph type requested: %s", graphTypeStr))
return 1
}
graphType = v
}
// Skip validation during graph generation - we want to see the graph even if
// it is invalid for some reason.
g, graphDiags := ctx.Graph(graphType, &terraform.ContextGraphOpts{
Verbose: verbose,
Validate: false,
})
diags = diags.Append(graphDiags)
if graphDiags.HasErrors() {
c.showDiagnostics(diags)
return 1
}
graphStr, err := terraform.GraphDot(g, &dag.DotOpts{
DrawCycles: drawCycles,
MaxDepth: moduleDepth,
Verbose: verbose,
})
if err != nil {
c.Ui.Error(fmt.Sprintf("Error converting graph: %s", err))
return 1
}
if diags.HasErrors() {
// For this command we only show diagnostics if there are errors,
// because printing out naked warnings could upset a naive program
// consuming our dot output.
c.showDiagnostics(diags)
return 1
}
c.Ui.Output(graphStr)
return 0
}
func (c *GraphCommand) Help() string {
helpText := `
Usage: terraform graph [options] [DIR]
Outputs the visual execution graph of Terraform resources according to
configuration files in DIR (or the current directory if omitted).
The graph is outputted in DOT format. The typical program that can
read this format is GraphViz, but many web services are also available
to read this format.
The -type flag can be used to control the type of graph shown. Terraform
creates different graphs for different operations. See the options below
for the list of types supported. The default type is "plan" if a
configuration is given, and "apply" if a plan file is passed as an
argument.
Options:
-draw-cycles Highlight any cycles in the graph with colored edges.
This helps when diagnosing cycle errors.
-type=plan Type of graph to output. Can be: plan, plan-destroy, apply,
validate, input, refresh.
-module-depth=n (deprecated) In prior versions of Terraform, specified the
depth of modules to show in the output.
`
return strings.TrimSpace(helpText)
}
func (c *GraphCommand) Synopsis() string {
return "Generate a Graphviz graph of the steps in an operation"
}