Add ability to set custom user agent information (#249)

* Add ability to set custom user agent information

* changelog

.changelog/249.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+Added ability to append custom text information to the default User Agent.
+```

docs/index.md

@@ -216,6 +216,14 @@ resource "davinci_flow" "mainflow" {
 
 > This above example was updated to reflect new DaVinci roles added on August 5th, 2023. The `DaVinci Admin` role is now required for user SSO and interaction with DaVinci APIs.
 
+### Custom User Agent information
+
+The DaVinci provider allows custom information to be appended to the default user agent string (that includes Terraform provider version information) by setting the `DAVINCI_TF_APPEND_USER_AGENT` environment variable.  This can be useful when troubleshooting issues with Ping Identity Support, or adding context to HTTP requests.
+
+```shell
+$ export DAVINCI_TF_APPEND_USER_AGENT="Jenkins/2.426.2"
+```
+
 <!-- schema generated by tfplugindocs -->
 ## Schema
 

examples/provider/provider-custom-user-agent.sh

@@ -0,0 +1 @@
+$ export DAVINCI_TF_APPEND_USER_AGENT="Jenkins/2.426.2"

internal/provider/provider.go

@@ -3,6 +3,7 @@ package provider
 import (
 	"context"
 	"fmt"
+	"os"
 	"strings"
 
 	"github.com/hashicorp/terraform-plugin-log/tflog"
@@ -113,14 +114,20 @@ func configure(version string, p *schema.Provider) func(context.Context, *schema
 
 		var diags diag.Diagnostics
 
+		userAgent := fmt.Sprintf("terraform-provider-davinci/%s", version)
+
+		if v := strings.TrimSpace(os.Getenv("DAVINCI_TF_APPEND_USER_AGENT")); v != "" {
+			userAgent += fmt.Sprintf(" %s", v)
+		}
+
 		cInput := client.ClientInput{
 			Username:        username,
 			Password:        password,
 			PingOneRegion:   region,
 			PingOneSSOEnvId: environment_id,
 			HostURL:         host_url,
 			AccessToken:     accessToken,
-			UserAgent:       fmt.Sprintf("terraform-provider-davinci/%s/go", version),
+			UserAgent:       userAgent,
 		}
 		c, err := retryableClient(&cInput)
 		if err != nil {

templates/index.md.tmpl

@@ -48,4 +48,10 @@ The following assumes that the PingOne worker app has been provided the `Environ
 
 > This above example was updated to reflect new DaVinci roles added on August 5th, 2023. The `DaVinci Admin` role is now required for user SSO and interaction with DaVinci APIs.
 
+### Custom User Agent information
+
+The DaVinci provider allows custom information to be appended to the default user agent string (that includes Terraform provider version information) by setting the `DAVINCI_TF_APPEND_USER_AGENT` environment variable.  This can be useful when troubleshooting issues with Ping Identity Support, or adding context to HTTP requests.
+
+{{ codefile "shell" (printf "%s" "examples/provider/provider-custom-user-agent.sh") }}
+
 {{ .SchemaMarkdown | trimspace }}