Class: Google::Apis::ServiceusageV1beta1::HttpRule
- Inherits:
-
Object
- Object
- Google::Apis::ServiceusageV1beta1::HttpRule
- Includes:
- Core::Hashable, Core::JsonObjectSupport
- Defined in:
- generated/google/apis/serviceusage_v1beta1/classes.rb,
generated/google/apis/serviceusage_v1beta1/representations.rb,
generated/google/apis/serviceusage_v1beta1/representations.rb
Overview
gRPC Transcoding
gRPC Transcoding is a feature for mapping between a gRPC method and one or
more HTTP REST endpoints. It allows developers to build a single API service
that supports both gRPC APIs and REST APIs. Many systems, including Google
APIs,
Cloud Endpoints, gRPC
Gateway,
and Envoy proxy support this feature
and use it for large scale production services.
HttpRule
defines the schema of the gRPC/REST mapping. The mapping specifies
how different portions of the gRPC request message are mapped to the URL
path, URL query parameters, and HTTP request body. It also controls how the
gRPC response message is mapped to the HTTP response body. HttpRule
is
typically specified as an google.api.http
annotation on the gRPC method.
Each mapping specifies a URL path template and an HTTP method. The path
template may refer to one or more fields in the gRPC request message, as long
as each field is a non-repeated field with a primitive (non-message) type.
The path template controls how fields of the request message are mapped to
the URL path.
Example:
service Messaging
rpc GetMessage(GetMessageRequest) returns (Message)
option (google.api.http) =
get: "/v1/
name=messages/""
;
message GetMessageRequest
string name = 1; // Mapped to URL path.
message Message
string text = 1; // The resource content.
This enables an HTTP REST to gRPC mapping as below:
HTTP | gRPC
-----|-----
GET /v1/messages/123456
| GetMessage(name: "messages/123456")
Any fields in the request message which are not bound by the path template
automatically become HTTP query parameters if there is no HTTP request body.
For example:
service Messaging
rpc GetMessage(GetMessageRequest) returns (Message)
option (google.api.http) =
get:"/v1/messages/
message_id"
;
message GetMessageRequest
message SubMessage
string subfield = 1;
string message_id = 1; // Mapped to URL path.
int64 revision = 2; // Mapped to URL query parameter
revision.
SubMessage sub = 3; // Mapped to URL query parameter
sub.subfield.
This enables a HTTP JSON to RPC mapping as below:
HTTP | gRPC
-----|-----
GET /v1/messages/123456?revision=2&sub.subfield=foo
| GetMessage(message_id:
"123456" revision: 2 sub: SubMessage(subfield: "foo"))
Note that fields which are mapped to URL query parameters must have a
primitive type or a repeated primitive type or a non-repeated message type.
In the case of a repeated type, the parameter can be repeated in the URL
as ...?param=A¶m=B
. In the case of a message type, each field of the
message is mapped to a separate parameter, such as
...?foo.a=A&foo.b=B&foo.c=C
.
For HTTP methods that allow a request body, the body
field
specifies the mapping. Consider a REST update method on the
message resource collection:
service Messaging
rpc UpdateMessage(UpdateMessageRequest) returns (Message)
option (google.api.http) =
patch: "/v1/messages/
message_id"
body: "message"
;
message UpdateMessageRequest
string message_id = 1; // mapped to the URL
Message message = 2; // mapped to the body
The following HTTP JSON to RPC mapping is enabled, where the
representation of the JSON in the request body is determined by
protos JSON encoding:
HTTP | gRPC
-----|-----
PATCH /v1/messages/123456
"text": "Hi!" `|
UpdateMessage(message_id: "
123456" message text: "Hi!"
)
The special name
can be used in the body mapping to define that
every field not bound by the path template should be mapped to the
request body. This enables the following alternative definition of
the update method:
service Messaging
rpc UpdateMessage(Message) returns (Message)
option (google.api.http) =
patch: "/v1/messages/message_id
"
body: ""
;
message Message
string message_id = 1;
string text = 2;
The following HTTP JSON to RPC mapping is enabled:
HTTP | gRPC
-----|-----
PATCH /v1/messages/123456 "text": "Hi!"
|
UpdateMessage(message_id: "
123456" text: "Hi!")
Note that when using
in the body mapping, it is not possible to
have HTTP parameters, as all fields not bound by the path end in
the body. This makes this option more rarely used in practice when
defining REST APIs. The common usage of
*is in custom methods
which don't use the URL at all for transferring data.
It is possible to define multiple HTTP methods for one RPC by using
the
additional_bindingsoption. Example:
service Messaging
rpc GetMessage(GetMessageRequest) returns (Message)
option (google.api.http) =
get: "/v1/messages/message_id
"
additional_bindings
get: "/v1/users/
user_id/messages/
message_id"
;
message GetMessageRequest
string message_id = 1;
string user_id = 2;
This enables the following two alternative HTTP JSON to RPC mappings:
HTTP | gRPC
-----|-----
GET /v1/messages/123456|
GetMessage(message_id: "123456")
GET /v1/users/me/messages/123456|
GetMessage(user_id: "me" message_id: "
123456")`
Rules for HTTP mapping
- Leaf request fields (recursive expansion nested messages in the request message) are classified into three categories:
- Fields referred by the path template. They are passed via the URL path.
- Fields referred by the HttpRule.body. They are passed via the HTTP request body.
- All other fields are passed via the URL query parameters, and the parameter name is the field path in the request message. A repeated field can be represented as multiple query parameters under the same name.
- If HttpRule.body is "*", there is no URL query parameter, all fields are passed via URL path and HTTP request body.
- If HttpRule.body is omitted, there is no HTTP request body, all
fields are passed via URL path and URL query parameters.
### Path template syntax
Template = "/" Segments [ Verb ] ;
Segments = Segment
"/" Segment
; Segment = "" | "" | LITERAL | Variable ; Variable = "" FieldPath [ "=" Segments ] "
" ; FieldPath = IDENT"." IDENT
; Verb = ":" LITERAL ; The syntax `matches a single URL path segment. The syntax
matches zero or more URL path segments, which must be the last part of the URL path except the
Verb. The syntax
Variablematches part of the URL path as specified by its template. A variable template must not contain other variables. If a variable matches a single path segment, its template may be omitted, e.g.
var
is equivalent to
var=*
. The syntax
LITERALmatches literal text in the URL path. If the
LITERALcontains any reserved character, such characters should be percent-encoded before the matching. If a variable contains exactly one path segment, such as
"var
"or
"var=*
", when such a variable is expanded into a URL path on the client side, all characters except
[-_.~0-9a-zA-Z]are percent-encoded. The server side does the reverse decoding. Such variables show up in the [Discovery Document](https://developers.google.com/discovery/v1/reference/apis) as
var
. If a variable contains multiple path segments, such as
"var=foo/*
"or
"`var="
, when such a variable is expanded into a URL path on the client side, all characters except[-_.~/0-9a-zA-Z]
are percent-encoded. The server side does the reverse decoding, except "%2F" and "%2f" are left unchanged. Such variables show up in the Discovery Document as+var
. ## Using gRPC API Service Configuration gRPC API Service Configuration (service config) is a configuration language for configuring a gRPC service to become a user-facing product. The service config is simply the YAML representation of thegoogle.api.Service
proto message. As an alternative to annotating your proto file, you can configure gRPC transcoding in your service config YAML files. You do this by specifying aHttpRule
that maps the gRPC method to a REST endpoint, achieving the same effect as the proto annotation. This can be particularly useful if you have a proto that is reused in multiple services. Note that any transcoding specified in the service config will override any matching transcoding configuration in the proto. Example: http: rules: # Selects a gRPC method and applies HttpRule to it. - selector: example.v1.Messaging.GetMessage
get: /v1/messages/
message_id
/sub.subfield
## Special notes When gRPC Transcoding is used to map a gRPC to JSON REST endpoints, the proto to JSON conversion must follow the proto3 specification . While the single segment variable follows the semantics of RFC 6570 Section 3.2.2 Simple String Expansion, the multi segment variable does not follow RFC 6570 Section 3.2.3 Reserved Expansion. The reason is that the Reserved Expansion does not expand special characters like?
and#
, which would lead to invalid URLs. As the result, gRPC Transcoding uses a custom encoding for multi segment variables. The path variables must not refer to any repeated or mapped field, because client libraries are not capable of handling such variable expansion. The path variables must not capture the leading "/" character. The reason is that the most common use case "var
" does not capture the leading "/" character. For consistency, all path variables must share the same behavior. Repeated message fields must not be mapped to URL query parameters, because no client library can support such complicated mapping. If an API needs to use a JSON array for request or response body, it can map the request or response body to a repeated field. However, some gRPC Transcoding implementations may not support this feature.
Instance Attribute Summary collapse
-
#additional_bindings ⇒ Array<Google::Apis::ServiceusageV1beta1::HttpRule>
Additional HTTP bindings for the selector.
-
#authorizations ⇒ Array<Google::Apis::ServiceusageV1beta1::AuthorizationRule>
Specifies the permission(s) required for an API element for the overall API request to succeed.
-
#body ⇒ String
The name of the request field whose value is mapped to the HTTP request body, or
*
for mapping all request fields not captured by the path pattern to the HTTP body, or omitted for not having any HTTP request body. -
#custom ⇒ Google::Apis::ServiceusageV1beta1::CustomHttpPattern
A custom pattern is used for defining custom HTTP verb.
-
#delete ⇒ String
Maps to HTTP DELETE.
-
#get ⇒ String
Maps to HTTP GET.
-
#media_download ⇒ Google::Apis::ServiceusageV1beta1::MediaDownload
Defines the Media configuration for a service in case of a download.
-
#media_upload ⇒ Google::Apis::ServiceusageV1beta1::MediaUpload
Defines the Media configuration for a service in case of an upload.
-
#patch ⇒ String
Maps to HTTP PATCH.
-
#post ⇒ String
Maps to HTTP POST.
-
#put ⇒ String
Maps to HTTP PUT.
-
#response_body ⇒ String
Optional.
-
#rest_collection ⇒ String
DO NOT USE.
-
#rest_method_name ⇒ String
DO NOT USE.
-
#selector ⇒ String
Selects a method to which this rule applies.
Instance Method Summary collapse
-
#initialize(**args) ⇒ HttpRule
constructor
A new instance of HttpRule.
-
#update!(**args) ⇒ Object
Update properties of this object.
Methods included from Core::JsonObjectSupport
Methods included from Core::Hashable
Constructor Details
#initialize(**args) ⇒ HttpRule
Returns a new instance of HttpRule
2325 2326 2327 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2325 def initialize(**args) update!(**args) end |
Instance Attribute Details
#additional_bindings ⇒ Array<Google::Apis::ServiceusageV1beta1::HttpRule>
Additional HTTP bindings for the selector. Nested bindings must
not contain an additional_bindings
field themselves (that is,
the nesting may only be one level deep).
Corresponds to the JSON property additionalBindings
2206 2207 2208 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2206 def additional_bindings @additional_bindings end |
#authorizations ⇒ Array<Google::Apis::ServiceusageV1beta1::AuthorizationRule>
Specifies the permission(s) required for an API element for the overall
API request to succeed. It is typically used to mark request message fields
that contain the name of the resource and indicates the permissions that
will be checked on that resource.
Corresponds to the JSON property authorizations
2214 2215 2216 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2214 def @authorizations end |
#body ⇒ String
The name of the request field whose value is mapped to the HTTP request
body, or *
for mapping all request fields not captured by the path
pattern to the HTTP body, or omitted for not having any HTTP request body.
NOTE: the referred field must be present at the top-level of the request
message type.
Corresponds to the JSON property body
2223 2224 2225 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2223 def body @body end |
#custom ⇒ Google::Apis::ServiceusageV1beta1::CustomHttpPattern
A custom pattern is used for defining custom HTTP verb.
Corresponds to the JSON property custom
2228 2229 2230 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2228 def custom @custom end |
#delete ⇒ String
Maps to HTTP DELETE. Used for deleting a resource.
Corresponds to the JSON property delete
2233 2234 2235 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2233 def delete @delete end |
#get ⇒ String
Maps to HTTP GET. Used for listing and getting information about
resources.
Corresponds to the JSON property get
2239 2240 2241 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2239 def get @get end |
#media_download ⇒ Google::Apis::ServiceusageV1beta1::MediaDownload
Defines the Media configuration for a service in case of a download.
Use this only for Scotty Requests. Do not use this for media support using
Bytestream, add instead [][google.bytestream.RestByteStream] as an API to
your configuration for Bytestream methods.
Corresponds to the JSON property mediaDownload
2247 2248 2249 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2247 def media_download @media_download end |
#media_upload ⇒ Google::Apis::ServiceusageV1beta1::MediaUpload
Defines the Media configuration for a service in case of an upload.
Use this only for Scotty Requests. Do not use this for media support using
Bytestream, add instead [][google.bytestream.RestByteStream] as an API to
your configuration for Bytestream methods.
Corresponds to the JSON property mediaUpload
2255 2256 2257 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2255 def media_upload @media_upload end |
#patch ⇒ String
Maps to HTTP PATCH. Used for updating a resource.
Corresponds to the JSON property patch
2260 2261 2262 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2260 def patch @patch end |
#post ⇒ String
Maps to HTTP POST. Used for creating a resource or performing an action.
Corresponds to the JSON property post
2265 2266 2267 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2265 def post @post end |
#put ⇒ String
Maps to HTTP PUT. Used for replacing a resource.
Corresponds to the JSON property put
2270 2271 2272 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2270 def put @put end |
#response_body ⇒ String
Optional. The name of the response field whose value is mapped to the HTTP
response body. When omitted, the entire response message will be used
as the HTTP response body.
NOTE: The referred field must be present at the top-level of the response
message type.
Corresponds to the JSON property responseBody
2279 2280 2281 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2279 def response_body @response_body end |
#rest_collection ⇒ String
DO NOT USE. This is an experimental field.
Optional. The REST collection name is by default derived from the URL
pattern. If specified, this field overrides the default collection name.
Example:
rpc AddressesAggregatedList(AddressesAggregatedListRequest)
returns (AddressesAggregatedListResponse)
option (google.api.http) =
get: "/v1/projects/project_id
/aggregated/addresses"
rest_collection: "projects.addresses"
;
This method has the automatically derived collection name
"projects.aggregated". Because, semantically, this rpc is actually an
operation on the "projects.addresses" collection, the rest_collection
field is configured to override the derived collection name.
Corresponds to the JSON property restCollection
2298 2299 2300 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2298 def rest_collection @rest_collection end |
#rest_method_name ⇒ String
DO NOT USE. This is an experimental field.
Optional. The rest method name is by default derived from the URL
pattern. If specified, this field overrides the default method name.
Example:
rpc CreateResource(CreateResourceRequest)
returns (CreateResourceResponse)
option (google.api.http) =
post: "/v1/resources",
body: "resource",
rest_method_name: "insert"
;
This method has the automatically derived rest method name
"create", but for backwards compatibility with apiary, it is specified as
insert.
Corresponds to the JSON property restMethodName
2317 2318 2319 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2317 def rest_method_name @rest_method_name end |
#selector ⇒ String
Selects a method to which this rule applies.
Refer to selector for syntax details.
Corresponds to the JSON property selector
2323 2324 2325 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2323 def selector @selector end |
Instance Method Details
#update!(**args) ⇒ Object
Update properties of this object
2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 |
# File 'generated/google/apis/serviceusage_v1beta1/classes.rb', line 2330 def update!(**args) @additional_bindings = args[:additional_bindings] if args.key?(:additional_bindings) @authorizations = args[:authorizations] if args.key?(:authorizations) @body = args[:body] if args.key?(:body) @custom = args[:custom] if args.key?(:custom) @delete = args[:delete] if args.key?(:delete) @get = args[:get] if args.key?(:get) @media_download = args[:media_download] if args.key?(:media_download) @media_upload = args[:media_upload] if args.key?(:media_upload) @patch = args[:patch] if args.key?(:patch) @post = args[:post] if args.key?(:post) @put = args[:put] if args.key?(:put) @response_body = args[:response_body] if args.key?(:response_body) @rest_collection = args[:rest_collection] if args.key?(:rest_collection) @rest_method_name = args[:rest_method_name] if args.key?(:rest_method_name) @selector = args[:selector] if args.key?(:selector) end |