package command import ( "fmt" "log" "os/exec" "path/filepath" "runtime" "strings" plugin "github.com/hashicorp/go-plugin" tfplugin "github.com/hashicorp/terraform/plugin" "github.com/hashicorp/terraform/plugin/discovery" "github.com/hashicorp/terraform/terraform" "github.com/kardianos/osext" ) // multiVersionProviderResolver is an implementation of // terraform.ResourceProviderResolver that matches the given version constraints // against a set of versioned provider plugins to find the newest version of // each that satisfies the given constraints. type multiVersionProviderResolver struct { Available discovery.PluginMetaSet } func choosePlugins(avail discovery.PluginMetaSet, reqd discovery.PluginRequirements) map[string]discovery.PluginMeta { candidates := avail.ConstrainVersions(reqd) ret := map[string]discovery.PluginMeta{} for name, metas := range candidates { if len(metas) == 0 { continue } ret[name] = metas.Newest() } return ret } func (r *multiVersionProviderResolver) ResolveProviders( reqd discovery.PluginRequirements, ) (map[string]terraform.ResourceProviderFactory, []error) { factories := make(map[string]terraform.ResourceProviderFactory, len(reqd)) var errs []error chosen := choosePlugins(r.Available, reqd) for name := range reqd { if newest, available := chosen[name]; available { digest, err := newest.SHA256() if err != nil { errs = append(errs, fmt.Errorf("provider.%s: failed to load plugin to verify its signature: %s", name, err)) continue } if !reqd[name].AcceptsSHA256(digest) { // This generic error message is intended to avoid troubling // users with implementation details. The main useful point // here is that they need to run "terraform init" to // fix this, which is covered by the UI code reporting these // error messages. errs = append(errs, fmt.Errorf("provider.%s: installed but not yet initialized", name)) continue } client := tfplugin.Client(newest) factories[name] = providerFactory(client) } else { errs = append(errs, fmt.Errorf("provider.%s: no suitable version installed", name)) } } return factories, errs } // the default location for automatically installed plugins func (m *Meta) pluginDir() string { return filepath.Join(m.DataDir(), "plugins", fmt.Sprintf("%s_%s", runtime.GOOS, runtime.GOARCH)) } // pluginDirs return a list of directories to search for plugins. // // Earlier entries in this slice get priority over later when multiple copies // of the same plugin version are found, but newer versions always override // older versions where both satisfy the provider version constraints. func (m *Meta) pluginDirs(includeAutoInstalled bool) []string { // When searching the following directories, earlier entries get precedence // if the same plugin version is found twice, but newer versions will // always get preference below regardless of where they are coming from. // TODO: Add auto-install dir, default vendor dir and optional override // vendor dir(s). dirs := []string{"."} // Look in the same directory as the Terraform executable. // If found, this replaces what we found in the config path. exePath, err := osext.Executable() if err != nil { log.Printf("[ERROR] Error discovering exe directory: %s", err) } else { dirs = append(dirs, filepath.Dir(exePath)) } if includeAutoInstalled { dirs = append(dirs, m.pluginDir()) } dirs = append(dirs, m.GlobalPluginDirs...) return dirs } // providerPluginSet returns the set of valid providers that were discovered in // the defined search paths. func (m *Meta) providerPluginSet() discovery.PluginMetaSet { plugins := discovery.FindPlugins("provider", m.pluginDirs(true)) plugins, _ = plugins.ValidateVersions() for p := range plugins { log.Printf("[DEBUG] found valid plugin: %q", p.Name) } return plugins } // providerPluginAutoInstalledSet returns the set of providers that exist // within the auto-install directory. func (m *Meta) providerPluginAutoInstalledSet() discovery.PluginMetaSet { plugins := discovery.FindPlugins("provider", []string{m.pluginDir()}) plugins, _ = plugins.ValidateVersions() for p := range plugins { log.Printf("[DEBUG] found valid plugin: %q", p.Name) } return plugins } // providerPluginManuallyInstalledSet returns the set of providers that exist // in all locations *except* the auto-install directory. func (m *Meta) providerPluginManuallyInstalledSet() discovery.PluginMetaSet { plugins := discovery.FindPlugins("provider", m.pluginDirs(false)) plugins, _ = plugins.ValidateVersions() for p := range plugins { log.Printf("[DEBUG] found valid plugin: %q", p.Name) } return plugins } func (m *Meta) providerResolver() terraform.ResourceProviderResolver { return &multiVersionProviderResolver{ Available: m.providerPluginSet(), } } // filter the requirements returning only the providers that we can't resolve func (m *Meta) missingPlugins(avail discovery.PluginMetaSet, reqd discovery.PluginRequirements) discovery.PluginRequirements { missing := make(discovery.PluginRequirements) for n, r := range reqd { log.Printf("[DEBUG] plugin requirements: %q=%q", n, r.Versions) } candidates := avail.ConstrainVersions(reqd) for name, versionSet := range reqd { if metas := candidates[name]; metas.Count() == 0 { missing[name] = versionSet } } return missing } func (m *Meta) provisionerFactories() map[string]terraform.ResourceProvisionerFactory { dirs := m.pluginDirs(true) plugins := discovery.FindPlugins("provisioner", dirs) plugins, _ = plugins.ValidateVersions() // For now our goal is to just find the latest version of each plugin // we have on the system. All provisioners should be at version 0.0.0 // currently, so there should actually only be one instance of each plugin // name here, even though the discovery interface forces us to pretend // that might not be true. factories := make(map[string]terraform.ResourceProvisionerFactory) // Wire up the internal provisioners first. These might be overridden // by discovered provisioners below. for name := range InternalProvisioners { client, err := internalPluginClient("provisioner", name) if err != nil { log.Printf("[WARN] failed to build command line for internal plugin %q: %s", name, err) continue } factories[name] = provisionerFactory(client) } byName := plugins.ByName() for name, metas := range byName { // Since we validated versions above and we partitioned the sets // by name, we're guaranteed that the metas in our set all have // valid versions and that there's at least one meta. newest := metas.Newest() client := tfplugin.Client(newest) factories[name] = provisionerFactory(client) } return factories } func internalPluginClient(kind, name string) (*plugin.Client, error) { cmdLine, err := BuildPluginCommandString(kind, name) if err != nil { return nil, err } // See the docstring for BuildPluginCommandString for why we need to do // this split here. cmdArgv := strings.Split(cmdLine, TFSPACE) cfg := &plugin.ClientConfig{ Cmd: exec.Command(cmdArgv[0], cmdArgv[1:]...), HandshakeConfig: tfplugin.Handshake, Managed: true, Plugins: tfplugin.PluginMap, } return plugin.NewClient(cfg), nil } func providerFactory(client *plugin.Client) terraform.ResourceProviderFactory { return func() (terraform.ResourceProvider, error) { // Request the RPC client so we can get the provider // so we can build the actual RPC-implemented provider. rpcClient, err := client.Client() if err != nil { return nil, err } raw, err := rpcClient.Dispense(tfplugin.ProviderPluginName) if err != nil { return nil, err } return raw.(terraform.ResourceProvider), nil } } func provisionerFactory(client *plugin.Client) terraform.ResourceProvisionerFactory { return func() (terraform.ResourceProvisioner, error) { // Request the RPC client so we can get the provisioner // so we can build the actual RPC-implemented provisioner. rpcClient, err := client.Client() if err != nil { return nil, err } raw, err := rpcClient.Dispense(tfplugin.ProvisionerPluginName) if err != nil { return nil, err } return raw.(terraform.ResourceProvisioner), nil } }