provider: add assume_role.0.duration and deprecate assume_role.0.duration_seconds

internal/provider/provider.go

@@ -1936,11 +1936,20 @@ func assumeRoleSchema() *schema.Schema {
 		MaxItems: 1,
 		Elem: &schema.Resource{
 			Schema: map[string]*schema.Schema{
+				"duration": {
+					Type:          schema.TypeString,
+					Optional:      true,
+					Description:   "The duration of the role session, e.g. 1h. Valid time units are ns, us (or µs), ms, s, h, or m.",
+					ValidateFunc:  verify.ValidTimeDuration,
+					ConflictsWith: []string{"assume_role.0.duration_seconds"},
+				},
 				"duration_seconds": {
-					Type:         schema.TypeInt,
-					Optional:     true,
-					Description:  "The duration, in seconds, of the role session.",
-					ValidateFunc: validation.IntBetween(900, 43200),
+					Type:          schema.TypeInt,
+					Optional:      true,
+					Deprecated:    "Use assume_role.0.duration instead",
+					Description:   "The duration, in seconds, of the role session.",
+					ValidateFunc:  validation.IntBetween(900, 43200),
+					ConflictsWith: []string{"assume_role.0.duration"},
 				},
 				"external_id": {
 					Type:        schema.TypeString,
@@ -2022,6 +2031,11 @@ func endpointsSchema() *schema.Schema {
 func expandAssumeRole(m map[string]interface{}) *awsbase.AssumeRole {
 	assumeRole := awsbase.AssumeRole{}
 
+	if v, ok := m["duration"].(string); ok && v != "" {
+		duration, _ := time.ParseDuration(v)
+		assumeRole.Duration = duration
+	}
+
 	if v, ok := m["duration_seconds"].(int); ok && v != 0 {
 		assumeRole.Duration = time.Duration(v) * time.Second
 	}

internal/verify/validate.go

@@ -257,6 +257,17 @@ func ValidStringIsJSONOrYAML(v interface{}, k string) (ws []string, errors []err
 	return
 }
 
+// ValidTimeDuration validates a string can be parsed as a valid time.Duration
+func ValidTimeDuration(v interface{}, k string) (ws []string, errors []error) {
+	_, err := time.ParseDuration(v.(string))
+
+	if err != nil {
+		errors = append(errors, fmt.Errorf("%q cannot be parsed as a valid time.Duration: %w", k, err))
+	}
+
+	return
+}
+
 // ValidTypeStringNullableBoolean provides custom error messaging for TypeString booleans
 // Some arguments require three values: true, false, and "" (unspecified).
 // This ValidateFunc returns a custom message since the message with

internal/verify/validate_test.go

@@ -6,6 +6,58 @@ import (
 	"testing"
 )
 
+func TestValidTimeDuration(t *testing.T) {
+	testCases := []struct {
+		val         interface{}
+		expectedErr *regexp.Regexp
+	}{
+		{
+			val:         "",
+			expectedErr: regexp.MustCompile(`cannot be parsed as a valid time.Duration`),
+		},
+		{
+			val:         "1",
+			expectedErr: regexp.MustCompile(`cannot be parsed as a valid time.Duration`),
+		},
+		{
+			val: "-10h",
+		},
+		{
+			val: "10h",
+		},
+		{
+			val: "1h10m10s",
+		},
+	}
+
+	matchErr := func(errs []error, r *regexp.Regexp) bool {
+		// err must match one provided
+		for _, err := range errs {
+			if r.MatchString(err.Error()) {
+				return true
+			}
+		}
+
+		return false
+	}
+
+	for i, tc := range testCases {
+		_, errs := ValidTimeDuration(tc.val, "test_property")
+
+		if len(errs) == 0 && tc.expectedErr == nil {
+			continue
+		}
+
+		if len(errs) != 0 && tc.expectedErr == nil {
+			t.Fatalf("expected test case %d to produce no errors, got %v", i, errs)
+		}
+
+		if !matchErr(errs, tc.expectedErr) {
+			t.Fatalf("expected test case %d to produce error matching \"%s\", got %v", i, tc.expectedErr, errs)
+		}
+	}
+}
+
 func TestValidTypeStringNullableBoolean(t *testing.T) {
 	testCases := []struct {
 		val         interface{}

website/docs/index.html.markdown

@@ -335,7 +335,8 @@ In addition to [generic `provider` arguments](https://www.terraform.io/docs/conf
 
 The `assume_role` configuration block supports the following optional arguments:
 
-* `duration_seconds` - (Optional) Number of seconds to restrict the assume role session duration. You can provide a value from 900 seconds (15 minutes) up to the maximum session duration setting for the role.
+* `duration` - (Optional, Conflicts with `duration_seconds`) The assume role duration represented as a string such as `300ms`, `-1.5h` or `2h45m`. Valid time units are `ns`, `us` (or `µs`), `ms`, `s`, `m`, `h`.
+* `duration_seconds` - (Optional, **Deprecated** use `duration` instead) Number of seconds to restrict the assume role session duration. You can provide a value from 900 seconds (15 minutes) up to the maximum session duration setting for the role.
 * `external_id` - (Optional) External identifier to use when assuming the role.
 * `policy` - (Optional) IAM Policy JSON describing further restricting permissions for the IAM Role being assumed.
 * `policy_arns` - (Optional) Set of Amazon Resource Names (ARNs) of IAM Policies describing further restricting permissions for the IAM Role being assumed.