Instances of this class created via copy-construction or copy-assignment always compare equal. Instances created with equal std::shared_ptr<*Connection> objects compare equal. Objects that compare equal share the same underlying resources.
Performance
Creating a new instance of this class is a relatively expensive operation, new objects establish new connections to the service. In contrast, copy-construction, move-construction, and the corresponding assignment operations are relatively efficient as the copies share all underlying resources.
Thread Safety
Concurrent access to different instances of this class, even if they compare equal, is guaranteed to work. Two or more threads operating on the same instance of this class is not guaranteed to work. Since copy-construction and move-construction is a relatively efficient operation, consider using such a copy when using this class from multiple threads.
Unary RPCs, such as the one wrapped by this function, receive a single request proto message which includes all the inputs for the RPC. In this case, the proto message is a google.appengine.v1.ListInstancesRequest. Proto messages are converted to C++ classes by Protobuf, using the Protobuf mapping rules.
opts
Options
Optional. Override the class-level options, such as retry and backoff policies.
Returns
Type
Description
StreamRange< google::appengine::v1::Instance >
a StreamRange to iterate of the results. See the documentation of this type for details. In brief, this class has begin() and end() member functions returning a iterator class meeting the input iterator requirements. The value type for this iterator is a StatusOr as the iteration may fail even after some values are retrieved successfully, for example, if there is a network disconnect. An empty set of results does not indicate an error, it indicates that there are no resources meeting the request criteria. On a successful iteration the StatusOr<T> contains elements of type google.appengine.v1.Instance, or rather, the C++ class generated by Protobuf from that type. Please consult the Protobuf documentation for details on the Protobuf mapping rules.
Unary RPCs, such as the one wrapped by this function, receive a single request proto message which includes all the inputs for the RPC. In this case, the proto message is a google.appengine.v1.GetInstanceRequest. Proto messages are converted to C++ classes by Protobuf, using the Protobuf mapping rules.
opts
Options
Optional. Override the class-level options, such as retry and backoff policies.
The instance might be automatically recreated based on the scaling settings of the version. For more information, see "How Instances are Managed" (standard environment | flexible environment).
To ensure that instances are not re-created and avoid getting billed, you can stop all instances within the target version by changing the serving status of the version to STOPPED with the apps.services.versions.patch method.
Unary RPCs, such as the one wrapped by this function, receive a single request proto message which includes all the inputs for the RPC. In this case, the proto message is a google.appengine.v1.DeleteInstanceRequest. Proto messages are converted to C++ classes by Protobuf, using the Protobuf mapping rules.
opts
Options
Optional. Override the class-level options, such as retry and backoff policies.
A future that becomes satisfied when the LRO (Long Running Operation) completes or the polling policy in effect for this call is exhausted. The future is satisfied with an error if the LRO completes with an error or the polling policy is exhausted. In this case the StatusOr returned by the future contains the error. If the LRO completes successfully the value of the future contains the LRO's result. For this RPC the result is a google.appengine.v1.OperationMetadataV1 proto message. The C++ class representing this message is created by Protobuf, using the Protobuf mapping rules.
Specifying the NoAwaitTag immediately returns the [google::longrunning::Operation] that corresponds to the Long Running Operation that has been started. No polling for operation status occurs.
This method accepts a google::longrunning::Operation that corresponds to a previously started Long Running Operation (LRO) and polls the status of the LRO in the background.
This allows you to use the SSH command to connect to the virtual machine where the instance lives. While in "debug mode", the instance continues to serve live traffic. You should delete the instance when you are done debugging and then allow the system to take over and determine if another instance should be started.
Only applicable for instances in App Engine flexible environment.
Unary RPCs, such as the one wrapped by this function, receive a single request proto message which includes all the inputs for the RPC. In this case, the proto message is a google.appengine.v1.DebugInstanceRequest. Proto messages are converted to C++ classes by Protobuf, using the Protobuf mapping rules.
opts
Options
Optional. Override the class-level options, such as retry and backoff policies.
A future that becomes satisfied when the LRO (Long Running Operation) completes or the polling policy in effect for this call is exhausted. The future is satisfied with an error if the LRO completes with an error or the polling policy is exhausted. In this case the StatusOr returned by the future contains the error. If the LRO completes successfully the value of the future contains the LRO's result. For this RPC the result is a google.appengine.v1.Instance proto message. The C++ class representing this message is created by Protobuf, using the Protobuf mapping rules.
Specifying the NoAwaitTag immediately returns the [google::longrunning::Operation] that corresponds to the Long Running Operation that has been started. No polling for operation status occurs.
This method accepts a google::longrunning::Operation that corresponds to a previously started Long Running Operation (LRO) and polls the status of the LRO in the background.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14 UTC."],[[["\u003cp\u003eThis document details the \u003ccode\u003eInstancesClient\u003c/code\u003e class for managing instances within Google App Engine, specifically focusing on its functionalities and usage in C++.\u003c/p\u003e\n"],["\u003cp\u003eThe class supports copy and move operations for efficient resource sharing and is thread-safe for concurrent access across different instances, but not for multiple threads operating on the same instance.\u003c/p\u003e\n"],["\u003cp\u003eIt offers functions to manage instances, including listing (\u003ccode\u003eListInstances\u003c/code\u003e), getting details (\u003ccode\u003eGetInstance\u003c/code\u003e), stopping (\u003ccode\u003eDeleteInstance\u003c/code\u003e), and enabling debugging (\u003ccode\u003eDebugInstance\u003c/code\u003e), with each function often requiring a specific request proto message.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eDeleteInstance\u003c/code\u003e and \u003ccode\u003eDebugInstance\u003c/code\u003e functions support Long Running Operations (LROs) and can be used with or without polling for operation status.\u003c/p\u003e\n"],["\u003cp\u003eThe latest release is 2.37.0-rc, and versions back to 2.11.0 are available, each with a corresponding class reference documentation.\u003c/p\u003e\n"]]],[],null,["# Class InstancesClient (2.27.0)\n\nVersion 2.27.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/appengine/latest/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.41.0](/cpp/docs/reference/appengine/2.41.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.40.0](/cpp/docs/reference/appengine/2.40.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.39.0](/cpp/docs/reference/appengine/2.39.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.38.0](/cpp/docs/reference/appengine/2.38.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.37.0](/cpp/docs/reference/appengine/2.37.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.36.0](/cpp/docs/reference/appengine/2.36.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.35.0](/cpp/docs/reference/appengine/2.35.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.34.0](/cpp/docs/reference/appengine/2.34.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.33.0](/cpp/docs/reference/appengine/2.33.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.32.0](/cpp/docs/reference/appengine/2.32.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.31.0](/cpp/docs/reference/appengine/2.31.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.30.0](/cpp/docs/reference/appengine/2.30.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.29.0](/cpp/docs/reference/appengine/2.29.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.28.0](/cpp/docs/reference/appengine/2.28.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.27.0](/cpp/docs/reference/appengine/2.27.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.26.0](/cpp/docs/reference/appengine/2.26.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.25.1](/cpp/docs/reference/appengine/2.25.1/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.24.0](/cpp/docs/reference/appengine/2.24.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.23.0](/cpp/docs/reference/appengine/2.23.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.22.1](/cpp/docs/reference/appengine/2.22.1/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.21.0](/cpp/docs/reference/appengine/2.21.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.20.0](/cpp/docs/reference/appengine/2.20.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.19.0](/cpp/docs/reference/appengine/2.19.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.18.0](/cpp/docs/reference/appengine/2.18.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.17.0](/cpp/docs/reference/appengine/2.17.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.16.0](/cpp/docs/reference/appengine/2.16.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.15.1](/cpp/docs/reference/appengine/2.15.1/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.14.0](/cpp/docs/reference/appengine/2.14.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.13.0](/cpp/docs/reference/appengine/2.13.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.12.0](/cpp/docs/reference/appengine/2.12.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient)\n- [2.11.0](/cpp/docs/reference/appengine/2.11.0/classgoogle_1_1cloud_1_1appengine__v1_1_1InstancesClient) \nManages instances of a version. \n\n###### Equality\n\nInstances of this class created via copy-construction or copy-assignment always compare equal. Instances created with equal `std::shared_ptr\u003c*Connection\u003e` objects compare equal. Objects that compare equal share the same underlying resources.\n\n###### Performance\n\nCreating a new instance of this class is a relatively expensive operation, new objects establish new connections to the service. In contrast, copy-construction, move-construction, and the corresponding assignment operations are relatively efficient as the copies share all underlying resources.\n\n###### Thread Safety\n\nConcurrent access to different instances of this class, even if they compare equal, is guaranteed to work. Two or more threads operating on the same instance of this class is not guaranteed to work. Since copy-construction and move-construction is a relatively efficient operation, consider using such a copy when using this class from multiple threads.\n\nConstructors\n------------\n\n### InstancesClient(InstancesClient const \\&)\n\nCopy and move support\n\n### InstancesClient(InstancesClient \\&\\&)\n\nCopy and move support\n\n### InstancesClient(std::shared_ptr\\\u003c InstancesConnection \\\u003e, Options)\n\nOperators\n---------\n\n### operator=(InstancesClient const \\&)\n\nCopy and move support\n\n### operator=(InstancesClient \\&\\&)\n\nCopy and move support\n\nFunctions\n---------\n\n### ListInstances(google::appengine::v1::ListInstancesRequest, Options)\n\nLists the instances of a version. \nTip: To aggregate details about instances over time, see the [Stackdriver Monitoring API](https://cloud.google.com/monitoring/api/ref_v3/rest/v3/projects.timeSeries/list).\n\n### GetInstance(google::appengine::v1::GetInstanceRequest const \\&, Options)\n\nGets instance information.\n\n### DeleteInstance(google::appengine::v1::DeleteInstanceRequest const \\&, Options)\n\nStops a running instance. \nThe instance might be automatically recreated based on the scaling settings of the version. For more information, see \"How Instances are Managed\" ([standard environment](https://cloud.google.com/appengine/docs/standard/python/how-instances-are-managed) \\| [flexible environment](https://cloud.google.com/appengine/docs/flexible/python/how-instances-are-managed)).\n\nTo ensure that instances are not re-created and avoid getting billed, you can stop all instances within the target version by changing the serving status of the version to `STOPPED` with the [`apps.services.versions.patch`](https://cloud.google.com/appengine/docs/admin-api/reference/rest/v1/apps.services.versions/patch) method.\n\n### DeleteInstance(NoAwaitTag, google::appengine::v1::DeleteInstanceRequest const \\&, Options)\n\nStops a running instance. \nSpecifying the [`NoAwaitTag`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1NoAwaitTag.html) immediately returns the \\[`google::longrunning::Operation`\\] that corresponds to the Long Running Operation that has been started. No polling for operation status occurs.\n\n### DeleteInstance(google::longrunning::Operation const \\&, Options)\n\nStops a running instance. \nThis method accepts a `google::longrunning::Operation` that corresponds to a previously started Long Running Operation (LRO) and polls the status of the LRO in the background.\n\n### DebugInstance(google::appengine::v1::DebugInstanceRequest const \\&, Options)\n\nEnables debugging on a VM instance. \nThis allows you to use the SSH command to connect to the virtual machine where the instance lives. While in \"debug mode\", the instance continues to serve live traffic. You should delete the instance when you are done debugging and then allow the system to take over and determine if another instance should be started.\n\nOnly applicable for instances in App Engine flexible environment.\n\n### DebugInstance(NoAwaitTag, google::appengine::v1::DebugInstanceRequest const \\&, Options)\n\nEnables debugging on a VM instance. \nSpecifying the [`NoAwaitTag`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1NoAwaitTag.html) immediately returns the \\[`google::longrunning::Operation`\\] that corresponds to the Long Running Operation that has been started. No polling for operation status occurs.\n\n### DebugInstance(google::longrunning::Operation const \\&, Options)\n\nEnables debugging on a VM instance. \nThis method accepts a `google::longrunning::Operation` that corresponds to a previously started Long Running Operation (LRO) and polls the status of the LRO in the background."]]
