581 lines
23 KiB
Go
581 lines
23 KiB
Go
package providercache
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import (
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"context"
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"fmt"
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"sort"
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"strings"
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"github.com/apparentlymart/go-versions/versions"
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"github.com/hashicorp/terraform/addrs"
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copydir "github.com/hashicorp/terraform/internal/copy"
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"github.com/hashicorp/terraform/internal/depsfile"
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"github.com/hashicorp/terraform/internal/getproviders"
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)
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// Installer is the main type in this package, representing a provider installer
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// with a particular configuration-specific cache directory and an optional
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// global cache directory.
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type Installer struct {
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// targetDir is the cache directory we're ultimately aiming to get the
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// requested providers installed into.
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targetDir *Dir
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// source is the provider source that the installer will use to discover
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// what provider versions are available for installation and to
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// find the source locations for any versions that are not already
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// available via one of the cache directories.
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source getproviders.Source
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// globalCacheDir is an optional additional directory that will, if
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// provided, be treated as a read-through cache when retrieving new
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// provider versions. That is, new packages are fetched into this
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// directory first and then linked into targetDir, which allows sharing
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// both the disk space and the download time for a particular provider
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// version between different configurations on the same system.
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globalCacheDir *Dir
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// builtInProviderTypes is an optional set of types that should be
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// considered valid to appear in the special terraform.io/builtin/...
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// namespace, which we use for providers that are built in to Terraform
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// and thus do not need any separate installation step.
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builtInProviderTypes []string
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// unmanagedProviderTypes is a set of provider addresses that should be
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// considered implemented, but that Terraform does not manage the
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// lifecycle for, and therefore does not need to worry about the
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// installation of.
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unmanagedProviderTypes map[addrs.Provider]struct{}
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}
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// NewInstaller constructs and returns a new installer with the given target
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// directory and provider source.
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//
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// A newly-created installer does not have a global cache directory configured,
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// but a caller can make a follow-up call to SetGlobalCacheDir to provide
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// one prior to taking any installation actions.
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//
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// The target directory MUST NOT also be an input consulted by the given source,
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// or the result is undefined.
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func NewInstaller(targetDir *Dir, source getproviders.Source) *Installer {
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return &Installer{
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targetDir: targetDir,
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source: source,
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}
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}
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// SetGlobalCacheDir activates a second tier of caching for the receiving
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// installer, with the given directory used as a read-through cache for
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// installation operations that need to retrieve new packages.
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//
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// The global cache directory for an installer must never be the same as its
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// target directory, and must not be used as one of its provider sources.
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// If these overlap then undefined behavior will result.
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func (i *Installer) SetGlobalCacheDir(cacheDir *Dir) {
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// A little safety check to catch straightforward mistakes where the
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// directories overlap. Better to panic early than to do
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// possibly-distructive actions on the cache directory downstream.
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if same, err := copydir.SameFile(i.targetDir.baseDir, cacheDir.baseDir); err == nil && same {
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panic(fmt.Sprintf("global cache directory %s must not match the installation target directory %s", cacheDir.baseDir, i.targetDir.baseDir))
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}
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i.globalCacheDir = cacheDir
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}
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// SetBuiltInProviderTypes tells the receiver to consider the type names in the
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// given slice to be valid as providers in the special special
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// terraform.io/builtin/... namespace that we use for providers that are
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// built in to Terraform and thus do not need a separate installation step.
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//
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// If a caller requests installation of a provider in that namespace, the
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// installer will treat it as a no-op if its name exists in this list, but
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// will produce an error if it does not.
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//
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// The default, if this method isn't called, is for there to be no valid
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// builtin providers.
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//
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// Do not modify the buffer under the given slice after passing it to this
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// method.
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func (i *Installer) SetBuiltInProviderTypes(types []string) {
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i.builtInProviderTypes = types
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}
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// SetUnmanagedProviderTypes tells the receiver to consider the providers
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// indicated by the passed addrs.Providers as unmanaged. Terraform does not
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// need to control the lifecycle of these providers, and they are assumed to be
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// running already when Terraform is started. Because these are essentially
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// processes, not binaries, Terraform will not do any work to ensure presence
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// or versioning of these binaries.
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func (i *Installer) SetUnmanagedProviderTypes(types map[addrs.Provider]struct{}) {
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i.unmanagedProviderTypes = types
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}
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// EnsureProviderVersions compares the given provider requirements with what
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// is already available in the installer's target directory and then takes
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// appropriate installation actions to ensure that suitable packages
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// are available in the target cache directory.
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//
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// The given mode modifies how the operation will treat providers that already
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// have acceptable versions available in the target cache directory. See the
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// documentation for InstallMode and the InstallMode values for more
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// information.
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//
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// The given context can be used to cancel the overall installation operation
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// (causing any operations in progress to fail with an error), and can also
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// include an InstallerEvents value for optional intermediate progress
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// notifications.
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//
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// If a given InstallerEvents subscribes to notifications about installation
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// failures then those notifications will be redundant with the ones included
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// in the final returned error value so callers should show either one or the
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// other, and not both.
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func (i *Installer) EnsureProviderVersions(ctx context.Context, locks *depsfile.Locks, reqs getproviders.Requirements, mode InstallMode) (*depsfile.Locks, error) {
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errs := map[addrs.Provider]error{}
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evts := installerEventsForContext(ctx)
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// We'll work with a copy of the given locks, so we can modify it and
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// return the updated locks without affecting the caller's object.
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// We'll add or replace locks in here during our work so that the final
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// locks file reflects what the installer has selected.
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locks = locks.DeepCopy()
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if cb := evts.PendingProviders; cb != nil {
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cb(reqs)
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}
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// Step 1: Which providers might we need to fetch a new version of?
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// This produces the subset of requirements we need to ask the provider
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// source about. If we're in the normal (non-upgrade) mode then we'll
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// just ask the source to confirm the continued existence of what
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// was locked, or otherwise we'll find the newest version matching the
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// configured version constraint.
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mightNeed := map[addrs.Provider]getproviders.VersionSet{}
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locked := map[addrs.Provider]bool{}
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for provider, versionConstraints := range reqs {
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if provider.IsBuiltIn() {
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// Built in providers do not require installation but we'll still
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// verify that the requested provider name is valid.
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valid := false
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for _, name := range i.builtInProviderTypes {
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if name == provider.Type {
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valid = true
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break
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}
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}
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var err error
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if valid {
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if len(versionConstraints) == 0 {
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// Other than reporting an event for the outcome of this
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// provider, we'll do nothing else with it: it's just
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// automatically available for use.
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if cb := evts.BuiltInProviderAvailable; cb != nil {
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cb(provider)
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}
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} else {
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// A built-in provider is not permitted to have an explicit
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// version constraint, because we can only use the version
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// that is built in to the current Terraform release.
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err = fmt.Errorf("built-in providers do not support explicit version constraints")
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}
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} else {
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err = fmt.Errorf("this Terraform release has no built-in provider named %q", provider.Type)
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}
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if err != nil {
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errs[provider] = err
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if cb := evts.BuiltInProviderFailure; cb != nil {
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cb(provider, err)
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}
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}
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continue
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}
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if _, ok := i.unmanagedProviderTypes[provider]; ok {
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// unmanaged providers do not require installation
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continue
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}
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acceptableVersions := versions.MeetingConstraints(versionConstraints)
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if !mode.forceQueryAllProviders() {
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// If we're not forcing potential changes of version then an
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// existing selection from the lock file takes priority over
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// the currently-configured version constraints.
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if lock := locks.Provider(provider); lock != nil {
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if !acceptableVersions.Has(lock.Version()) {
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err := fmt.Errorf(
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"locked provider %s %s does not match configured version constraint %s; must use terraform init -upgrade to allow selection of new versions",
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provider, lock.Version(), getproviders.VersionConstraintsString(versionConstraints),
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)
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errs[provider] = err
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// This is a funny case where we're returning an error
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// before we do any querying at all. To keep the event
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// stream consistent without introducing an extra event
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// type, we'll emit an artificial QueryPackagesBegin for
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// this provider before we indicate that it failed using
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// QueryPackagesFailure.
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if cb := evts.QueryPackagesBegin; cb != nil {
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cb(provider, versionConstraints, true)
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}
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if cb := evts.QueryPackagesFailure; cb != nil {
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cb(provider, err)
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}
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continue
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}
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acceptableVersions = versions.Only(lock.Version())
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locked[provider] = true
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}
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}
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mightNeed[provider] = acceptableVersions
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}
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// Step 2: Query the provider source for each of the providers we selected
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// in the first step and select the latest available version that is
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// in the set of acceptable versions.
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//
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// This produces a set of packages to install to our cache in the next step.
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need := map[addrs.Provider]getproviders.Version{}
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NeedProvider:
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for provider, acceptableVersions := range mightNeed {
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if err := ctx.Err(); err != nil {
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// If our context has been cancelled or reached a timeout then
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// we'll abort early, because subsequent operations against
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// that context will fail immediately anyway.
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return nil, err
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}
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if cb := evts.QueryPackagesBegin; cb != nil {
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cb(provider, reqs[provider], locked[provider])
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}
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available, warnings, err := i.source.AvailableVersions(ctx, provider)
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if err != nil {
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// TODO: Consider retrying a few times for certain types of
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// source errors that seem likely to be transient.
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errs[provider] = err
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if cb := evts.QueryPackagesFailure; cb != nil {
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cb(provider, err)
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}
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// We will take no further actions for this provider.
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continue
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}
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if len(warnings) > 0 {
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if cb := evts.QueryPackagesWarning; cb != nil {
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cb(provider, warnings)
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}
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}
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available.Sort() // put the versions in increasing order of precedence
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for i := len(available) - 1; i >= 0; i-- { // walk backwards to consider newer versions first
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if acceptableVersions.Has(available[i]) {
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need[provider] = available[i]
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if cb := evts.QueryPackagesSuccess; cb != nil {
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cb(provider, available[i])
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}
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continue NeedProvider
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}
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}
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// If we get here then the source has no packages that meet the given
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// version constraint, which we model as a query error.
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if locked[provider] {
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// This situation should be a rare one: it suggests that a
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// version was previously available but was yanked for some
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// reason.
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lock := locks.Provider(provider)
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err = fmt.Errorf("the previously-selected version %s is no longer available", lock.Version())
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} else {
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err = fmt.Errorf("no available releases match the given constraints %s", getproviders.VersionConstraintsString(reqs[provider]))
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}
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errs[provider] = err
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if cb := evts.QueryPackagesFailure; cb != nil {
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cb(provider, err)
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}
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}
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// Step 3: For each provider version we've decided we need to install,
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// install its package into our target cache (possibly via the global cache).
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authResults := map[addrs.Provider]*getproviders.PackageAuthenticationResult{} // record auth results for all successfully fetched providers
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targetPlatform := i.targetDir.targetPlatform // we inherit this to behave correctly in unit tests
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for provider, version := range need {
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if err := ctx.Err(); err != nil {
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// If our context has been cancelled or reached a timeout then
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// we'll abort early, because subsequent operations against
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// that context will fail immediately anyway.
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return nil, err
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}
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lock := locks.Provider(provider)
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var preferredHashes []getproviders.Hash
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if lock != nil && lock.Version() == version { // hash changes are expected if the version is also changing
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preferredHashes = lock.PreferredHashes()
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}
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if i.globalCacheDir != nil {
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// Step 3a: If our global cache already has this version available then
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// we'll just link it in.
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if cached := i.globalCacheDir.ProviderVersion(provider, version); cached != nil {
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if cb := evts.LinkFromCacheBegin; cb != nil {
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cb(provider, version, i.globalCacheDir.baseDir)
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}
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if _, err := cached.ExecutableFile(); err != nil {
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err := fmt.Errorf("provider binary not found: %s", err)
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errs[provider] = err
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if cb := evts.LinkFromCacheFailure; cb != nil {
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cb(provider, version, err)
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}
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continue
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}
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err := i.targetDir.LinkFromOtherCache(cached, preferredHashes)
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if err != nil {
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errs[provider] = err
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if cb := evts.LinkFromCacheFailure; cb != nil {
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cb(provider, version, err)
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}
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continue
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}
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// We'll fetch what we just linked to make sure it actually
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// did show up there.
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new := i.targetDir.ProviderVersion(provider, version)
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if new == nil {
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err := fmt.Errorf("after linking %s from provider cache at %s it is still not detected in the target directory; this is a bug in Terraform", provider, i.globalCacheDir.baseDir)
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errs[provider] = err
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if cb := evts.LinkFromCacheFailure; cb != nil {
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cb(provider, version, err)
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}
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continue
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}
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// The LinkFromOtherCache call above should've verified that
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// the package matches one of the hashes previously recorded,
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// if any. We'll now augment those hashes with one freshly
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// calculated from the package we just linked, which allows
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// the lock file to gradually transition to recording newer hash
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// schemes when they become available.
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var newHashes []getproviders.Hash
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if lock != nil && lock.Version() == version {
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// If the version we're installing is identical to the
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// one we previously locked then we'll keep all of the
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// hashes we saved previously and add to it. Otherwise
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// we'll be starting fresh, because each version has its
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// own set of packages and thus its own hashes.
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newHashes = append(newHashes, preferredHashes...)
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// NOTE: The behavior here is unfortunate when a particular
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// provider version was already cached on the first time
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// the current configuration requested it, because that
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// means we don't currently get the opportunity to fetch
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// and verify the checksums for the new package from
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// upstream. That's currently unavoidable because upstream
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// checksums are in the "ziphash" format and so we can't
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// verify them against our cache directory's unpacked
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// packages: we'd need to go fetch the package from the
|
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// origin and compare against it, which would defeat the
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// purpose of the global cache.
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//
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// If we fetch from upstream on the first encounter with
|
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// a particular provider then we'll end up in the other
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// codepath below where we're able to also include the
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// checksums from the origin registry.
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}
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newHash, err := cached.Hash()
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if err != nil {
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err := fmt.Errorf("after linking %s from provider cache at %s, failed to compute a checksum for it: %s", provider, i.globalCacheDir.baseDir, err)
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errs[provider] = err
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if cb := evts.LinkFromCacheFailure; cb != nil {
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cb(provider, version, err)
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}
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continue
|
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}
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// The hashes slice gets deduplicated in the lock file
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// implementation, so we don't worry about potentially
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// creating a duplicate here.
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newHashes = append(newHashes, newHash)
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lock = locks.SetProvider(provider, version, reqs[provider], newHashes)
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|
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if cb := evts.LinkFromCacheSuccess; cb != nil {
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cb(provider, version, new.PackageDir)
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|
}
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continue // Don't need to do full install, then.
|
|
}
|
|
}
|
|
|
|
// Step 3b: Get the package metadata for the selected version from our
|
|
// provider source.
|
|
//
|
|
// This is the step where we might detect and report that the provider
|
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// isn't available for the current platform.
|
|
if cb := evts.FetchPackageMeta; cb != nil {
|
|
cb(provider, version)
|
|
}
|
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meta, err := i.source.PackageMeta(ctx, provider, version, targetPlatform)
|
|
if err != nil {
|
|
errs[provider] = err
|
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if cb := evts.FetchPackageFailure; cb != nil {
|
|
cb(provider, version, err)
|
|
}
|
|
continue
|
|
}
|
|
|
|
// Step 3c: Retrieve the package indicated by the metadata we received,
|
|
// either directly into our target directory or via the global cache
|
|
// directory.
|
|
if cb := evts.FetchPackageBegin; cb != nil {
|
|
cb(provider, version, meta.Location)
|
|
}
|
|
var installTo, linkTo *Dir
|
|
if i.globalCacheDir != nil {
|
|
installTo = i.globalCacheDir
|
|
linkTo = i.targetDir
|
|
} else {
|
|
installTo = i.targetDir
|
|
linkTo = nil // no linking needed
|
|
}
|
|
authResult, err := installTo.InstallPackage(ctx, meta, preferredHashes)
|
|
if err != nil {
|
|
// TODO: Consider retrying for certain kinds of error that seem
|
|
// likely to be transient. For now, we just treat all errors equally.
|
|
errs[provider] = err
|
|
if cb := evts.FetchPackageFailure; cb != nil {
|
|
cb(provider, version, err)
|
|
}
|
|
continue
|
|
}
|
|
new := installTo.ProviderVersion(provider, version)
|
|
if new == nil {
|
|
err := fmt.Errorf("after installing %s it is still not detected in the target directory; this is a bug in Terraform", provider)
|
|
errs[provider] = err
|
|
if cb := evts.FetchPackageFailure; cb != nil {
|
|
cb(provider, version, err)
|
|
}
|
|
continue
|
|
}
|
|
if _, err := new.ExecutableFile(); err != nil {
|
|
err := fmt.Errorf("provider binary not found: %s", err)
|
|
errs[provider] = err
|
|
if cb := evts.FetchPackageFailure; cb != nil {
|
|
cb(provider, version, err)
|
|
}
|
|
continue
|
|
}
|
|
if linkTo != nil {
|
|
// We skip emitting the "LinkFromCache..." events here because
|
|
// it's simpler for the caller to treat them as mutually exclusive.
|
|
// We can just subsume the linking step under the "FetchPackage..."
|
|
// series here (and that's why we use FetchPackageFailure below).
|
|
// We also don't do a hash check here because we already did that
|
|
// as part of the installTo.InstallPackage call above.
|
|
err := linkTo.LinkFromOtherCache(new, nil)
|
|
if err != nil {
|
|
errs[provider] = err
|
|
if cb := evts.FetchPackageFailure; cb != nil {
|
|
cb(provider, version, err)
|
|
}
|
|
continue
|
|
}
|
|
}
|
|
authResults[provider] = authResult
|
|
|
|
// The InstallPackage call above should've verified that
|
|
// the package matches one of the hashes previously recorded,
|
|
// if any. We'll now augment those hashes with a new set populated
|
|
// with the hashes returned by the upstream source and from the
|
|
// package we've just installed, which allows the lock file to
|
|
// gradually transition to newer hash schemes when they become
|
|
// available.
|
|
//
|
|
// This is assuming that if a package matches both a hash we saw before
|
|
// _and_ a new hash then the new hash is a valid substitute for
|
|
// the previous hash.
|
|
//
|
|
// The hashes slice gets deduplicated in the lock file
|
|
// implementation, so we don't worry about potentially
|
|
// creating duplicates here.
|
|
var newHashes []getproviders.Hash
|
|
if lock != nil && lock.Version() == version {
|
|
// If the version we're installing is identical to the
|
|
// one we previously locked then we'll keep all of the
|
|
// hashes we saved previously and add to it. Otherwise
|
|
// we'll be starting fresh, because each version has its
|
|
// own set of packages and thus its own hashes.
|
|
newHashes = append(newHashes, preferredHashes...)
|
|
}
|
|
newHash, err := new.Hash()
|
|
if err != nil {
|
|
err := fmt.Errorf("after installing %s, failed to compute a checksum for it: %s", provider, err)
|
|
errs[provider] = err
|
|
if cb := evts.FetchPackageFailure; cb != nil {
|
|
cb(provider, version, err)
|
|
}
|
|
continue
|
|
}
|
|
newHashes = append(newHashes, newHash)
|
|
if authResult.SignedByAnyParty() {
|
|
// We'll trust new hashes from upstream only if they were verified
|
|
// as signed by a suitable key. Otherwise, we'd record only
|
|
// a new hash we just calculated ourselves from the bytes on disk,
|
|
// and so the hashes would cover only the current platform.
|
|
newHashes = append(newHashes, meta.AcceptableHashes()...)
|
|
}
|
|
lock = locks.SetProvider(provider, version, reqs[provider], newHashes)
|
|
|
|
if cb := evts.FetchPackageSuccess; cb != nil {
|
|
cb(provider, version, new.PackageDir, authResult)
|
|
}
|
|
}
|
|
|
|
// Emit final event for fetching if any were successfully fetched
|
|
if cb := evts.ProvidersFetched; cb != nil && len(authResults) > 0 {
|
|
cb(authResults)
|
|
}
|
|
|
|
if len(errs) > 0 {
|
|
return locks, InstallerError{
|
|
ProviderErrors: errs,
|
|
}
|
|
}
|
|
return locks, nil
|
|
}
|
|
|
|
// InstallMode customizes the details of how an install operation treats
|
|
// providers that have versions already cached in the target directory.
|
|
type InstallMode rune
|
|
|
|
const (
|
|
// InstallNewProvidersOnly is an InstallMode that causes the installer
|
|
// to accept any existing version of a requested provider that is already
|
|
// cached as long as it's in the given version sets, without checking
|
|
// whether new versions are available that are also in the given version
|
|
// sets.
|
|
InstallNewProvidersOnly InstallMode = 'N'
|
|
|
|
// InstallUpgrades is an InstallMode that causes the installer to check
|
|
// all requested providers to see if new versions are available that
|
|
// are also in the given version sets, even if a suitable version of
|
|
// a given provider is already available.
|
|
InstallUpgrades InstallMode = 'U'
|
|
)
|
|
|
|
func (m InstallMode) forceQueryAllProviders() bool {
|
|
return m == InstallUpgrades
|
|
}
|
|
|
|
// InstallerError is an error type that may be returned (but is not guaranteed)
|
|
// from Installer.EnsureProviderVersions to indicate potentially several
|
|
// separate failed installation outcomes for different providers included in
|
|
// the overall request.
|
|
type InstallerError struct {
|
|
ProviderErrors map[addrs.Provider]error
|
|
}
|
|
|
|
func (err InstallerError) Error() string {
|
|
addrs := make([]addrs.Provider, 0, len(err.ProviderErrors))
|
|
for addr := range err.ProviderErrors {
|
|
addrs = append(addrs, addr)
|
|
}
|
|
sort.Slice(addrs, func(i, j int) bool {
|
|
return addrs[i].LessThan(addrs[j])
|
|
})
|
|
var b strings.Builder
|
|
b.WriteString("some providers could not be installed:\n")
|
|
for _, addr := range addrs {
|
|
providerErr := err.ProviderErrors[addr]
|
|
fmt.Fprintf(&b, "- %s: %s\n", addr, providerErr)
|
|
}
|
|
return b.String()
|
|
}
|