allow late config binding (dynamic_config flag) (#58)

* allow late config binding (dynamic_config flag)
* bump gocmlclient to 0.0.19

Author: rschmied

CHANGELOG.md

@@ -2,6 +2,15 @@
 
 Lists the changes in the provider.
 
+## Version 0.6.1
+
+- allow dynamic configuration of the provider by introducing a "dynamic_config"
+  provider config flag. This defaults to `false`. When set to `true` then the
+  provider configuration is only validated when actual resources are read or
+  created. This is for specific use cases like AWS deployments where the CML2
+  instance IP is only known after the EC2 instance has been created.
+- bump the gocmlclient to 0.0.18
+
 ## Version 0.6.0
 
 - allow empty node configurations (fixes #50)

docs/index.md

@@ -62,6 +62,7 @@ provider "cml2" {
 ### Optional
 
 - `cacert` (String) A CA CERT, PEM encoded. When provided, the controller cert will be checked against it.  Otherwise, the system trust anchors will be used.
+- `dynamic_config` (Boolean) Does late binding of the provider configuration. If set to `true` then provider configuration errors will only be caught when resources and data sources are actually created/read. Defaults to `false`
 - `password` (String, Sensitive) CML2 password.
 - `skip_verify` (Boolean) Disables TLS certificate verification (default is false -- will not skip / it will verify the certificate!)
 - `token` (String, Sensitive) CML2 API token (JWT).

go.mod

@@ -9,7 +9,7 @@ require (
 	github.com/hashicorp/terraform-plugin-go v0.15.0
 	github.com/hashicorp/terraform-plugin-log v0.8.0
 	github.com/hashicorp/terraform-plugin-sdk/v2 v2.26.1
-	github.com/rschmied/gocmlclient v0.0.17
+	github.com/rschmied/gocmlclient v0.0.19
 	github.com/stretchr/testify v1.8.2
 )
 
@@ -58,7 +58,6 @@ require (
 	github.com/russross/blackfriday v1.6.0 // indirect
 	github.com/shopspring/decimal v1.3.1 // indirect
 	github.com/spf13/cast v1.5.0 // indirect
-	github.com/stretchr/objx v0.5.0 // indirect
 	github.com/vmihailenco/msgpack v4.0.4+incompatible // indirect
 	github.com/vmihailenco/msgpack/v5 v5.3.5 // indirect
 	github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect

go.sum

@@ -146,10 +146,8 @@ github.com/posener/complete v1.1.1/go.mod h1:em0nMJCgc9GFtwrmVmEMR/ZL6WyhyjMBndr
 github.com/posener/complete v1.2.3 h1:NP0eAhjcjImqslEwo/1hq7gpajME0fTLTezBKDqfXqo=
 github.com/posener/complete v1.2.3/go.mod h1:WZIdtGGp+qx0sLrYKtIRAruyNpv6hFCicSgv7Sy7s/s=
 github.com/rogpeppe/go-internal v1.6.1 h1:/FiVV8dS/e+YqF2JvO3yXRFbBLTIuSDkuC7aBOAvL+k=
-github.com/rschmied/gocmlclient v0.0.16 h1:dWlXb4IJfwyuEqfI1/8RbebKHe+CkBEBsthq61NI6pY=
-github.com/rschmied/gocmlclient v0.0.16/go.mod h1:j5oDyPNNiM/Q1rOE3IKqTJW2lt5ANDcGPolWyr9ddMc=
-github.com/rschmied/gocmlclient v0.0.17 h1:I2G6jo4O6gkhME19QIIgzuE0WE25P3NFyOKWxGQPFuM=
-github.com/rschmied/gocmlclient v0.0.17/go.mod h1:AxuKqPKsWwqRtThJk5Ozi8B2Hp7/dR/A94zDq3gLQ90=
+github.com/rschmied/gocmlclient v0.0.19 h1:mrC2boo67juuzJPCinmV9EIu8Dlwm9n0vii3vQUePhQ=
+github.com/rschmied/gocmlclient v0.0.19/go.mod h1:AxuKqPKsWwqRtThJk5Ozi8B2Hp7/dR/A94zDq3gLQ90=
 github.com/rschmied/mockresponder v1.0.4 h1:VFXa9Y9QJ/5oZFhKoqh9u3HQlbjcBfE9pxI+BanMlEs=
 github.com/russross/blackfriday v1.6.0 h1:KqfZb0pUVN2lYqZUYRddxF4OR8ZMURnJIG5Y3VRLtww=
 github.com/russross/blackfriday v1.6.0/go.mod h1:ti0ldHuxg49ri4ksnFxlkCfN+hvslNlmVHqNRXXJNAY=

internal/cmlschema/provider.go

@@ -7,13 +7,14 @@ import (
 
 // ProviderModel describes the provider configuration data model.
 type ProviderModel struct {
-	Address    types.String `tfsdk:"address"`
-	Username   types.String `tfsdk:"username"`
-	Password   types.String `tfsdk:"password"`
-	Token      types.String `tfsdk:"token"`
-	CAcert     types.String `tfsdk:"cacert"`
-	SkipVerify types.Bool   `tfsdk:"skip_verify"`
-	UseCache   types.Bool   `tfsdk:"use_cache"`
+	Address       types.String `tfsdk:"address"`
+	Username      types.String `tfsdk:"username"`
+	Password      types.String `tfsdk:"password"`
+	Token         types.String `tfsdk:"token"`
+	CAcert        types.String `tfsdk:"cacert"`
+	SkipVerify    types.Bool   `tfsdk:"skip_verify"`
+	UseCache      types.Bool   `tfsdk:"use_cache"`
+	DynamicConfig types.Bool   `tfsdk:"dynamic_config"`
 }
 
 func Provider() map[string]schema.Attribute {
@@ -49,5 +50,9 @@ func Provider() map[string]schema.Attribute {
 			Description: "Enables the client cache, this is considered experimental (default is false -- will not use the cache!)",
 			Optional:    true,
 		},
+		"dynamic_config": schema.BoolAttribute{
+			MarkdownDescription: "Does late binding of the provider configuration. If set to `true` then provider configuration errors will only be caught when resources and data sources are actually created/read. Defaults to `false`",
+			Optional:            true,
+		},
 	}
 }

internal/cmlschema/provider_test.go

@@ -18,7 +18,7 @@ func TestProviderAttrs(t *testing.T) {
 
 	got, diag := schema.TypeAtPath(context.TODO(), path.Root("address"))
 	assert.Equal(t, types.StringType, got)
-	assert.Equal(t, 7, len(schema.Attributes))
+	assert.Equal(t, 8, len(schema.Attributes))
 	assert.False(t, diag.HasError())
 	t.Log(diag.Errors())
 }

internal/common/configure.go

@@ -6,12 +6,17 @@ import (
 	"sync"
 
 	"github.com/hashicorp/terraform-plugin-framework/datasource"
+	"github.com/hashicorp/terraform-plugin-framework/diag"
 	"github.com/hashicorp/terraform-plugin-framework/resource"
+	"github.com/hashicorp/terraform-plugin-framework/types"
+	"github.com/hashicorp/terraform-plugin-log/tflog"
 	cmlclient "github.com/rschmied/gocmlclient"
+	"github.com/rschmied/terraform-provider-cml2/internal/cmlschema"
 )
 
 type ProviderConfig struct {
 	client *cmlclient.Client
+	data   *cmlschema.ProviderModel
 	mu     *sync.Mutex
 }
 
@@ -27,13 +32,95 @@ func (r *ProviderConfig) Unlock() {
 	r.mu.Unlock()
 }
 
-func NewProviderConfig(client *cmlclient.Client) *ProviderConfig {
+func NewProviderConfig(data *cmlschema.ProviderModel) *ProviderConfig {
 	return &ProviderConfig{
-		client: client,
+		client: nil,
 		mu:     new(sync.Mutex),
+		data:   data,
 	}
 }
 
+func (r *ProviderConfig) Initialize(ctx context.Context, data *cmlschema.ProviderModel, diag diag.Diagnostics) *ProviderConfig {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	if r.client != nil {
+		return r
+	}
+
+	// check if provided auth configuration makes sense
+	if data.Token.IsNull() &&
+		(data.Username.IsNull() || data.Password.IsNull()) {
+		diag.AddError(
+			"Required configuration missing",
+			"null check: either username and password or a token must be provided",
+		)
+	}
+
+	if len(data.Token.ValueString()) == 0 &&
+		(len(data.Username.ValueString()) == 0 || len(data.Password.ValueString()) == 0) {
+		diag.AddError(
+			"Required configuration missing",
+			"value check: either username and password or a token must be provided",
+		)
+	}
+
+	if len(data.Token.ValueString()) > 0 && len(data.Username.ValueString()) > 0 {
+		diag.AddWarning(
+			"Conflicting configuration",
+			"both token and username / password were provided")
+	}
+
+	// an address must be specified
+	if len(data.Address.ValueString()) == 0 {
+		diag.AddError(
+			"Required configuration missing",
+			"A server address must be configured to use th CML2 provider",
+		)
+	}
+	if data.SkipVerify.IsNull() {
+		tflog.Warn(ctx, "unspecified certificate verification, will verify")
+		data.SkipVerify = types.BoolValue(false)
+	}
+
+	if data.UseCache.IsNull() {
+		data.UseCache = types.BoolValue(false)
+	} else if data.UseCache.ValueBool() {
+		diag.AddWarning(
+			"Experimental feature enabled",
+			"\"use_cache\" is considered experimental and may not work as expected; use with care",
+		)
+	}
+
+	// create a new CML2 client
+	client := cmlclient.New(
+		data.Address.ValueString(),
+		data.SkipVerify.ValueBool(),
+		data.UseCache.ValueBool(),
+	)
+	if len(data.Username.ValueString()) > 0 {
+		client.SetUsernamePassword(
+			data.Username.ValueString(),
+			data.Password.ValueString(),
+		)
+	}
+	if len(data.Token.ValueString()) > 0 {
+		client.SetToken(data.Token.ValueString())
+	}
+
+	if len(data.CAcert.ValueString()) > 0 {
+		err := client.SetCACert([]byte(data.CAcert.ValueString()))
+		if err != nil {
+			diag.AddError(
+				"Configuration issue",
+				fmt.Sprintf("Provided certificate could not be used: %s", err),
+			)
+		}
+	}
+	r.client = client
+	return r
+}
+
 func DatasourceConfigure(ctx context.Context, req datasource.ConfigureRequest, resp *datasource.ConfigureResponse) *ProviderConfig {
 	// Prevent panic if the provider has not been configured.
 	if req.ProviderData == nil {
@@ -47,7 +134,7 @@ func DatasourceConfigure(ctx context.Context, req datasource.ConfigureRequest, r
 		)
 		return nil
 	}
-	return config
+	return config.Initialize(ctx, config.data, resp.Diagnostics)
 }
 
 func ResourceConfigure(ctx context.Context, req resource.ConfigureRequest, resp *resource.ConfigureResponse) *ProviderConfig {
@@ -64,5 +151,5 @@ func ResourceConfigure(ctx context.Context, req resource.ConfigureRequest, resp
 		)
 		return nil
 	}
-	return config
+	return config.Initialize(ctx, config.data, resp.Diagnostics)
 }

internal/provider/provider.go

@@ -2,15 +2,11 @@ package provider
 
 import (
 	"context"
-	"fmt"
 
 	"github.com/hashicorp/terraform-plugin-framework/datasource"
 	"github.com/hashicorp/terraform-plugin-framework/provider"
 	"github.com/hashicorp/terraform-plugin-framework/resource"
 	"github.com/hashicorp/terraform-plugin-framework/types"
-	"github.com/hashicorp/terraform-plugin-log/tflog"
-
-	cmlclient "github.com/rschmied/gocmlclient"
 
 	"github.com/rschmied/terraform-provider-cml2/internal/common"
 	d_groups "github.com/rschmied/terraform-provider-cml2/internal/provider/datasource/groups"
@@ -51,76 +47,21 @@ func (p *CML2Provider) Configure(ctx context.Context, req provider.ConfigureRequ
 		return
 	}
 
-	// check if provided auth configuration makes sense
-	if data.Token.IsNull() &&
-		(data.Username.IsNull() || data.Password.IsNull()) {
-		resp.Diagnostics.AddError(
-			"Required configuration missing",
-			fmt.Sprintf("null check: either username and password or a token must be provided %T", p),
-		)
-	}
-
-	if len(data.Token.ValueString()) == 0 &&
-		(len(data.Username.ValueString()) == 0 || len(data.Password.ValueString()) == 0) {
-		resp.Diagnostics.AddError(
-			"Required configuration missing",
-			fmt.Sprintf("value check: either username and password or a token must be provided %T", p),
-		)
-	}
-
-	if len(data.Token.ValueString()) > 0 && len(data.Username.ValueString()) > 0 {
-		resp.Diagnostics.AddWarning(
-			"Conflicting configuration",
-			"both token and username / password were provided")
-	}
-
-	// an address must be specified
-	if len(data.Address.ValueString()) == 0 {
-		resp.Diagnostics.AddError(
-			"Required configuration missing",
-			fmt.Sprintf("A server address must be configured to use provider %s", p.name),
-		)
-	}
-	if data.SkipVerify.IsNull() {
-		tflog.Warn(ctx, "unspecified certificate verification, will verify")
-		data.SkipVerify = types.BoolValue(false)
-	}
-
-	if data.UseCache.IsNull() {
-		data.UseCache = types.BoolValue(false)
-	} else if data.UseCache.ValueBool() {
-		resp.Diagnostics.AddWarning(
-			"Experimental feature enabled",
-			"\"use_cache\" is considered experimental and may not work as expected; use with care",
-		)
+	dynamic_config := false
+	if data.DynamicConfig.IsNull() {
+		data.DynamicConfig = types.BoolValue(false)
+	} else if data.DynamicConfig.ValueBool() {
+		dynamic_config = true
+		// resp.Diagnostics.AddWarning(
+		// 	"Dynamic configuration",
+		// 	"\"dynamic_config\" does late binding of the provider configuration",
+		// )
 	}
 
-	// create a new CML2 client
-	client := cmlclient.New(
-		data.Address.ValueString(),
-		data.SkipVerify.ValueBool(),
-		data.UseCache.ValueBool(),
-	)
-	if len(data.Username.ValueString()) > 0 {
-		client.SetUsernamePassword(
-			data.Username.ValueString(),
-			data.Password.ValueString(),
-		)
-	}
-	if len(data.Token.ValueString()) > 0 {
-		client.SetToken(data.Token.ValueString())
-	}
-
-	if len(data.CAcert.ValueString()) > 0 {
-		err := client.SetCACert([]byte(data.CAcert.ValueString()))
-		if err != nil {
-			resp.Diagnostics.AddError(
-				"Configuration issue",
-				fmt.Sprintf("Provided certificate could not be used: %s", err),
-			)
-		}
+	config := common.NewProviderConfig(&data)
+	if !dynamic_config {
+		config.Initialize(ctx, &data, resp.Diagnostics)
 	}
-	config := common.NewProviderConfig(client)
 	resp.DataSourceData = config
 	resp.ResourceData = config
 }