fixes #3423 adds filter to data source aws_eip

this addes the ability to search for EIP’s via tags or other attribute that EIP’s can use in a filter.

This did highlight a known issue with regrads to how terraform eval’s data sources before they should if be the resourse is a computed value. This is only an issue if the data block is referencing a resource that is created at the same time. If referencing a pre exiting resource this does not happen.

the test config testAccDataSourceAwsEipFilterConfig makes a interpol ref to force terraform to eval the data block after the resource has either been created or read in `values = ["${aws_eip.test.tags.Name}”]` see the following links

hashicorp/terraform#10603
hashicorp/terraform#17173

aws/data_source_aws_eip.go

@@ -14,6 +14,7 @@ func dataSourceAwsEip() *schema.Resource {
 		Read: dataSourceAwsEipRead,
 
 		Schema: map[string]*schema.Schema{
+			"filter": dataSourceFiltersSchema(),
 			"id": {
 				Type:     schema.TypeString,
 				Optional: true,
@@ -31,14 +32,26 @@ func dataSourceAwsEip() *schema.Resource {
 func dataSourceAwsEipRead(d *schema.ResourceData, meta interface{}) error {
 	conn := meta.(*AWSClient).ec2conn
 
+	filters, filtersOk := d.GetOk("filter")
+	id, idOk := d.GetOk("id")
+	publicIP, publicIPOk := d.GetOk("public_ip")
+
+	if (idOk || publicIPOk) && filtersOk {
+		return fmt.Errorf("filter cannot be used when id or public_ip is set")
+	}
+
 	req := &ec2.DescribeAddressesInput{}
 
-	if id, ok := d.GetOk("id"); ok {
+	if idOk {
 		req.AllocationIds = []*string{aws.String(id.(string))}
 	}
 
-	if public_ip := d.Get("public_ip"); public_ip != "" {
-		req.PublicIps = []*string{aws.String(public_ip.(string))}
+	if publicIPOk {
+		req.PublicIps = []*string{aws.String(publicIP.(string))}
+	}
+
+	if filtersOk {
+		req.Filters = buildAwsDataSourceFilters(filters.(*schema.Set))
 	}
 
 	log.Printf("[DEBUG] Reading EIP: %s", req)

aws/data_source_aws_eip_test.go

@@ -39,6 +39,21 @@ func TestAccDataSourceAwsEip_vpc(t *testing.T) {
 	})
 }
 
+func TestAccDataSourceAwsEip_filter(t *testing.T) {
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: testAccDataSourceAwsEipFilterConfig,
+				Check: resource.ComposeTestCheckFunc(
+					testAccDataSourceAwsEipCheck("data.aws_eip.by_filter", "aws_eip.test"),
+				),
+			},
+		},
+	})
+}
+
 func testAccDataSourceAwsEipCheck(data_path string, resource_path string) resource.TestCheckFunc {
 	return func(s *terraform.State) error {
 		rs, ok := s.RootModule().Resources[data_path]
@@ -103,3 +118,24 @@ data "aws_eip" "test_vpc_by_public_ip" {
   public_ip = "${aws_eip.test_vpc.public_ip}"
 }
 `
+
+const testAccDataSourceAwsEipFilterConfig = `
+provider "aws" {
+  region = "us-west-2"
+}
+
+resource "aws_eip" "test" {
+	vpc = true
+
+	tags {
+    	Name = "testeip"
+  	}
+}
+
+data "aws_eip" "by_filter" {
+  filter {
+    name   = "tag:Name"
+    values = ["${aws_eip.test.tags.Name}"]
+  }
+}
+`