Snapshot
A Snapshot object will give you access to your Cloud Pub/Sub snapshot.
Snapshots are sometimes retrieved when using various methods:
Snapshots may be created with:
You can use snapshots to seek a subscription to a specific point in time.
Constructor
Snapshot
new Snapshot()
Example
//-
// From {@link PubSub#getSnapshots}:
//-
pubsub.getSnapshots((err, snapshots) => {
// `snapshots` is an array of Snapshot objects.
});
//-
// From {@link PubSub#getSnapshotsStream}:
//-
pubsub.getSnapshotsStream()
.on('error', console.error)
.on('data', (snapshot) => {
// `snapshot` is a Snapshot object.
});
//-
// From {@link PubSub#snapshot}:
//-
const snapshot = pubsub.snapshot('my-snapshot');
// snapshot is a Snapshot object.
//-
// Create a snapshot with {module:pubsub/subscription#createSnapshot}:
//-
const subscription = pubsub.subscription('my-subscription');
subscription.createSnapshot('my-snapshot', (err, snapshot) => {
if (!err) {
// `snapshot` is a Snapshot object.
}
});
//-
// Seek to your snapshot:
//-
const subscription = pubsub.subscription('my-subscription');
subscription.seek('my-snapshot', (err) => {
if (err) {
// Error handling omitted.
}
});
Methods
create
create(name, callback)
Create a snapshot with the given name.
This is only available if you accessed this object through Subscription#snapshot.
Parameter |
|||||||||
---|---|---|---|---|---|---|---|---|---|
name |
string Name of the snapshot. |
||||||||
callback |
Optional function() The callback function. Values in
|
Example
const subscription = pubsub.subscription('my-subscription');
const snapshot = subscription.snapshot('my-snapshot');
const callback = (err, snapshot, apiResponse) => {
if (!err) {
// The snapshot was created successfully.
}
};
snapshot.create('my-snapshot', callback);
//-
// If the callback is omitted, we'll return a Promise.
//-
snapshot.create('my-snapshot').then((data) => {
const snapshot = data[0];
const apiResponse = data[1];
});
delete
delete(callback)
Delete the snapshot.
Parameter |
|||||||
---|---|---|---|---|---|---|---|
callback |
Optional function() The callback function. Values in
|
Example
snapshot.delete((err, apiResponse) => {});
//-
// If the callback is omitted, we'll return a Promise.
//-
snapshot.delete().then((data) => {
const apiResponse = data[0];
});
seek
seek(callback)
Seeks an existing subscription to the snapshot.
This is only available if you accessed this object through Subscription#snapshot.
Parameter |
|||||||
---|---|---|---|---|---|---|---|
callback |
function() The callback function. Values in
|
Example
const subscription = pubsub.subscription('my-subscription');
const snapshot = subscription.snapshot('my-snapshot');
snapshot.seek((err, apiResponse) => {});
//-
// If the callback is omitted, we'll return a Promise.
//-
snapshot.seek().then((data) => {
const apiResponse = data[0];
});