Reference documentation and code samples for the Google API Common Protos Client class RoutingRule.
Specifies the routing information that should be sent along with the request in the form of routing header.
NOTE: All service configuration rules follow the "last one wins" order.
The examples below will apply to an RPC which has the following request type:
Message Definition:
message Request {
// The name of the Table
// Values can be of the following formats:
// - projects/<project>/tables/<table>
// - projects/<project>/instances/<instance>/tables/<table>
// - region/<region>/zones/<zone>/tables/<table>
string table_name = 1;
// This value specifies routing for replication.
// It can be in the following formats:
// - profiles/<profile_id>
// - a legacy profile_id
that can be any string
string app_profile_id = 2;
}
Example message:
{
table_name: projects/proj_foo/instances/instance_bar/table/table_baz,
app_profile_id: profiles/prof_qux
}
The routing header consists of one or multiple key-value pairs. Every key
and value must be percent-encoded, and joined together in the format of
key1=value1&key2=value2
.
In the examples below I am skipping the percent-encoding for readablity.
Example 1
Extracting a field from the request to put into the routing header
unchanged, with the key equal to the field name.
annotation:
option (google.api.routing) = {
// Take the app_profile_id
.
routing_parameters {
field: "app_profile_id"
}
};
result:
x-goog-request-params: app_profile_id=profiles/prof_qux
Example 2
Extracting a field from the request to put into the routing header
unchanged, with the key different from the field name.
annotation:
option (google.api.routing) = {
// Take the app_profile_id
, but name it routing_id
in the header.
routing_parameters {
field: "app_profile_id"
path_template: "{routing_id=}"
}
};
result:
x-goog-request-params: routing_id=profiles/prof_qux
Example 3
Extracting a field from the request to put into the routing
header, while matching a path template syntax on the field's value.
NB: it is more useful to send nothing than to send garbage for the purpose
of dynamic routing, since garbage pollutes cache. Thus the matching.
Sub-example 3a
The field matches the template.
annotation:
option (google.api.routing) = {
// Take the table_name
, if it's well-formed (with project-based
// syntax).
routing_parameters {
field: "table_name"
path_template: "{table_name=projects//instances//}"
}
};
result:
x-goog-request-params:
table_name=projects/proj_foo/instances/instance_bar/table/table_baz
Sub-example 3b
The field does not match the template.
annotation:
option (google.api.routing) = {
// Take the table_name
, if it's well-formed (with region-based
// syntax).
routing_parameters {
field: "table_name"
path_template: "{table_name=regions//zones//}"
}
};
result:
}"
}
routing_parameters {
field: "table_name"
path_template: "{table_name=projects//instances//}"
}
};
result:
x-goog-request-params:
table_name=projects/proj_foo/instances/instance_bar/table/table_baz
Example 4
Extracting a single routing header key-value pair by matching a
template syntax on (a part of) a single request field.
annotation:
option (google.api.routing) = {
// Take just the project id from the table_name
field.
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/*}/"
}
};
result:
x-goog-request-params: routing_id=projects/proj_foo
Example 5
Extracting a single routing header key-value pair by matching
several conflictingly named path templates on (parts of) a single request
field. The last template to match "wins" the conflict.
annotation:
option (google.api.routing) = {
// If the table_name
does not have instances information,
// take just the project id for routing.
// Otherwise take project + instance.
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/}/"
}
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects//instances/}/"
}
};
result:
x-goog-request-params:
routing_id=projects/proj_foo/instances/instance_bar
Example 6
Extracting multiple routing header key-value pairs by matching
several non-conflicting path templates on (parts of) a single request field.
Sub-example 6a
Make the templates strict, so that if the table_name
does not
have an instance information, nothing is sent.
annotation:
option (google.api.routing) = {
// The routing code needs two keys instead of one composite
// but works only for the tables with the "project-instance" name
// syntax.
routing_parameters {
field: "table_name"
path_template: "{project_id=projects/}/instances//"
}
routing_parameters {
field: "table_name"
path_template: "projects//{instance_id=instances/}/"
}
};
result:
x-goog-request-params:
project_id=projects/proj_foo&instance_id=instances/instance_bar
Sub-example 6b
Make the templates loose, so that if the table_name
does not
have an instance information, just the project id part is sent.
annotation:
option (google.api.routing) = {
// The routing code wants two keys instead of one composite
// but will work with just the project_id
for tables without
// an instance in the table_name
.
routing_parameters {
field: "table_name"
path_template: "{project_id=projects/}/"
}
routing_parameters {
field: "table_name"
path_template: "projects//{instance_id=instances/}/"
}
};
result (is the same as 6a for our example message because it has the instance
information):
x-goog-request-params:
project_id=projects/proj_foo&instance_id=instances/instance_bar
Example 7
Extracting multiple routing header key-value pairs by matching
several path templates on multiple request fields.
NB: note that here there is no way to specify sending nothing if one of the
fields does not match its template. E.g. if the table_name
is in the wrong
format, the project_id
will not be sent, but the routing_id
will be.
The backend routing code has to be aware of that and be prepared to not
receive a full complement of keys if it expects multiple.
annotation:
option (google.api.routing) = {
// The routing needs both project_id
and routing_id
// (from the app_profile_id
field) for routing.
routing_parameters {
field: "table_name"
path_template: "{project_id=projects/}/"
}
routing_parameters {
field: "app_profile_id"
path_template: "{routing_id=}"
}
};
result:
x-goog-request-params:
project_id=projects/proj_foo&routing_id=profiles/prof_qux
Example 8
Extracting a single routing header key-value pair by matching
several conflictingly named path templates on several request fields. The
last template to match "wins" the conflict.
annotation:
option (google.api.routing) = {
// The routing_id
can be a project id or a region id depending on
// the table name format, but only if the app_profile_id
is not set.
// If app_profile_id
is set it should be used instead.
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/}/"
}
routing_parameters {
field: "table_name"
path_template: "{routing_id=regions/*}/"
}
routing_parameters {
field: "app_profile_id"
path_template: "{routing_id=}"
}
};
result:
x-goog-request-params: routing_id=profiles/prof_qux
Example 9
Bringing it all together.
annotation:
option (google.api.routing) = {
// For routing both table_location
and a routing_id
are needed.
//
// table_location can be either an instance id or a region+zone id.
//
// For routing_id
, take the value of app_profile_id
// - If it's in the format profiles/<profile_id>
, send
// just the <profile_id>
part.
// - If it's any other literal, send it as is.
// If the app_profile_id
is empty, and the table_name
starts with
// the project_id, send that instead.
routing_parameters {
field: "table_name"
path_template: "projects//{table_location=instances/}/tables/"
}
routing_parameters {
field: "table_name"
path_template: "{table_location=regions//zones/}/tables/"
}
routing_parameters {
field: "table_name"
path_template: "{routing_id=projects/*}/"
}
routing_parameters {
field: "app_profile_id"
path_template: "{routing_id=*}"
}
routing_parameters {
field: "app_profile_id"
path_template: "profiles/{routing_id=}"
}
};
result:
x-goog-request-params:
table_location=instances/instance_bar&routing_id=prof_qux
Generated from protobuf message google.api.RoutingRule
Namespace
Google \ ApiMethods
__construct
Constructor.
Parameters | |
---|---|
Name | Description |
data |
array
Optional. Data for populating the Message object. |
↳ routing_parameters |
array<RoutingParameter>
A collection of Routing Parameter specifications. NOTE: If multiple Routing Parameters describe the same key (via the |
getRoutingParameters
A collection of Routing Parameter specifications.
NOTE: If multiple Routing Parameters describe the same key
(via the path_template
field or via the field
field when
path_template
is not provided), "last one wins" rule
determines which Parameter gets used.
See the examples for more details.
Returns | |
---|---|
Type | Description |
Google\Protobuf\Internal\RepeatedField |
setRoutingParameters
A collection of Routing Parameter specifications.
NOTE: If multiple Routing Parameters describe the same key
(via the path_template
field or via the field
field when
path_template
is not provided), "last one wins" rule
determines which Parameter gets used.
See the examples for more details.
Parameter | |
---|---|
Name | Description |
var |
array<RoutingParameter>
|
Returns | |
---|---|
Type | Description |
$this |