interfaces/Observer.md

+[@hiveio/workerbee v1.27.6-rc9-stable.250129105732](../globals) / Observer
+
+# Interface: Observer\<T\>
+
+An object interface that defines a set of callback functions a user can use to get notified
+
+## Type Parameters
+
+• **T**
+
+## Properties
+
+### complete()
+
+> **complete**: () => `void`
+
+A callback function that gets called by the producer if and when it has no more
+values to provide (by calling `next` callback function). This means that no error
+has happened. This callback can't be called more than one time, it can't be called
+if the `error` callback function have been called previously, nor it can't be called
+if the consumer has unsubscribed.
+
+#### Returns
+
+`void`
+
+#### Defined in
+
+[src/types/subscribable.ts:26](https://gitlab.syncad.com/hive/workerbee/-/blob/c86a48da91e9edabfae917e1bf4069da65412f97/src/types/subscribable.ts#L26)
+
+***
+
+### error()
+
+> **error**: (`err`) => `void`
+
+A callback function that gets called by the producer if and when it encountered a
+problem of any kind. The errored value will be provided through the `err` parameter.
+This callback can't be called more than one time, it can't be called if the
+`complete` callback function have been called previously, nor it can't be called if
+the consumer has unsubscribed.
+
+#### Parameters
+
+• **err**: `any`
+
+#### Returns
+
+`void`
+
+#### Defined in
+
+[src/types/subscribable.ts:18](https://gitlab.syncad.com/hive/workerbee/-/blob/c86a48da91e9edabfae917e1bf4069da65412f97/src/types/subscribable.ts#L18)
+
+***
+
+### next()
+
+> **next**: (`value`) => `void`
+
+A callback function that gets called by the producer during the subscription when
+the producer "has" the `value`. It won't be called if `error` or `complete` callback
+functions have been called, nor after the consumer has unsubscribed.
+
+#### Parameters
+
+• **value**: `T`
+
+#### Returns
+
+`void`
+
+#### Defined in
+
+[src/types/subscribable.ts:10](https://gitlab.syncad.com/hive/workerbee/-/blob/c86a48da91e9edabfae917e1bf4069da65412f97/src/types/subscribable.ts#L10)