add update support for redis (#246)

Merged PR #246.

products/redis/api.yaml

@@ -27,14 +27,14 @@ objects:
     base_url: |
       projects/{{project}}/locations/{{region}}/instances?instanceId={{name}}
     self_link: projects/{{project}}/locations/{{region}}/instances/{{name}}
+    update_verb: :PATCH
     description: |
       A Google Cloud Redis instance.
     references: !ruby/object:Api::Resource::ReferenceLinks
       guides:
         'Official Documentation':
           'https://cloud.google.com/memorystore/docs/redis/'
       api: 'https://cloud.google.com/memorystore/docs/redis/reference/rest/'
-    input: true # TODO(danawillow): support for updates
 <%=
   # Cloud Redis takes a fair bit of time to provision, try six minutes.
   indent(compile_file({timeouts: { insert_sec: 6 * 60 }},
@@ -46,6 +46,7 @@ objects:
         description: |
           The name of the Redis region of the instance.
         required: true
+        input: true
     properties:
       - !ruby/object:Api::Type::String
         name: alternativeLocationId
@@ -54,12 +55,14 @@ objects:
           against zonal failures by provisioning it across two zones.
           If provided, it must be a different zone from the one provided in
           [locationId].
+        input: true
       - !ruby/object:Api::Type::String
         name: authorizedNetwork
         description: |
           The full name of the Google Compute Engine network to which the
           instance is connected. If left unspecified, the default network
           will be used.
+        input: true
       - !ruby/object:Api::Type::Time
         name: createTime
         description: |
@@ -75,6 +78,7 @@ objects:
           instances, this can be either [locationId] or [alternativeLocationId]
           and can change after a failover event.
         output: true
+        input: true
       - !ruby/object:Api::Type::String
         name: displayName
         description: |
@@ -98,11 +102,13 @@ objects:
           instances will be created across two zones for protection against
           zonal failures. If [alternativeLocationId] is also provided, it must
           be different from [locationId].
+        input: true
       - !ruby/object:Api::Type::String
         name: name
         description: |
           The ID of the instance or a fully qualified identifier for the instance. 
         required: true
+        input: true
       - !ruby/object:Api::Type::Integer
         name: memorySizeGb
         description: Redis memory size in GiB.
@@ -118,6 +124,7 @@ objects:
           version will be used. Updating the version will perform an
           upgrade/downgrade to the new version. Currently, the supported values
           are REDIS_3_2 for Redis 3.2.
+        input: true
       - !ruby/object:Api::Type::String
         name: reservedIpRange
         description: |
@@ -126,6 +133,7 @@ objects:
           block, for example, 10.0.0.0/29 or 192.168.0.0/29. Ranges must be
           unique and non-overlapping with existing subnets in an authorized
           network.
+        input: true
       - !ruby/object:Api::Type::Enum
         name: tier
         description: |
@@ -137,3 +145,4 @@ objects:
           - :BASIC
           - :STANDARD_HA
         default_value: :BASIC
+        input: true

products/redis/terraform.yaml

@@ -20,6 +20,7 @@ overrides: !ruby/object:Provider::ResourceOverrides
     custom_code: !ruby/object:Provider::Terraform::CustomCode
       decoder: 'templates/terraform/decoders/redis_instance.erb'
       encoder: 'templates/terraform/encoders/redis_instance.erb'
+      pre_update: 'templates/terraform/pre_update/redis_instance.erb'
     examples: |
       ### Basic Usage
       ```hcl

templates/terraform/pre_update/redis_instance.erb

@@ -0,0 +1,16 @@
+updateMask := []string{}
+if d.HasChange("display_name") {
+	updateMask = append(updateMask, "displayName")
+}
+if d.HasChange("labels") {
+	updateMask = append(updateMask, "labels")
+}
+if d.HasChange("memory_size_gb") {
+	updateMask = append(updateMask, "memorySizeGb")
+}
+// updateMask is a URL parameter but not present in the schema, so replaceVars
+// won't set it
+url, err = addQueryParams(url, map[string]string{"updateMask": strings.Join(updateMask, ",")})
+if err != nil {
+	return err
+}

templates/terraform/transport.go

@@ -106,15 +106,12 @@ func sendRequest(config *Config, method, rawurl string, body map[string]interfac
 		}
 	}
 
-	u, err := url.Parse(rawurl)
+	u, err := addQueryParams(rawurl, map[string]string{"alt": "json"})
 	if err != nil {
 		return nil, err
 	}
-	q := u.Query()
-	q.Set("alt", "json")
-	u.RawQuery = q.Encode()
 
-	req, err := http.NewRequest(method, u.String(), &buf)
+	req, err := http.NewRequest(method, u, &buf)
 	if err != nil {
 		return nil, err
 	}
@@ -136,6 +133,19 @@ func sendRequest(config *Config, method, rawurl string, body map[string]interfac
 	return result, nil
 }
 
+func addQueryParams(rawurl string, params map[string]string) (string, error) {
+	u, err := url.Parse(rawurl)
+	if err != nil {
+		return "", err
+	}
+	q := u.Query()
+	for k, v := range params {
+		q.Set(k, v)
+	}
+	u.RawQuery = q.Encode()
+	return u.String(), nil
+}
+
 func replaceVars(d TerraformResourceData, config *Config, linkTmpl string) (string, error) {
 	re := regexp.MustCompile("{{([[:word:]]+)}}")
 	var project, region, zone string