# ConnectionManagementSessionMixin
Auto-generated from the @jbrowse/mobx-state-tree model in the source — see the [developer guide](https://jbrowse.org/jb2/docs/developer_guide/) for concepts. Built into JBrowse core. [View source](https://github.com/GMOD/jbrowse-components/blob/main/packages/product-core/src/Session/Connections.ts).
Adds connections to a session: the connection instances it has made, and
the configs of the connection tracks the user opened, so those tracks load
on session restore without reconnecting.
## Properties
| Member | Description |
| --- | --- |
| **connectionInstances**
connectionInstances: types.stripDefault( types.array(pluginManager.pluggableMstType('connection', 'stateModel')), [], ) | |
| **connectionTrackConfigs**
connectionTrackConfigs: types.stripDefault( types.frozen<Record<string, ConnectionTrackConfigEntry>>(), {}, ) | Persisted configs of connection tracks the user has opened, keyed by trackId. Unlike `connectionInstances` (stripped from snapshots, holds the whole fetched hub), this holds only the tracks in use, so an open connection track resolves synchronously on session load without re-establishing the connection. |
## Getters
| Member | Description |
| --- | --- |
| **connections**
(ConfigNodeProps<…> & ConfigNodeActions & ConfigNodeBrand<ConfigurationSchemaType<{ readonly name: { type: "string"; } & { defaultValue: string; }; readonly assemblyNames: { type: "stringArray"; } & { defaultValue: unknown; }; connectionId: { type: "string"; } & { defaultValue: string; }; type: { type: "string"; } & { defaultValue: string; }; }, ConfigurationSchemaOptions<undefined, "connectionId", true, ConfigurationSchemaRequirement<Partial<Record<string, string[]>>, string>, any>>>)[] | |
## Actions
| Member | Description |
| --- | --- |
| **makeConnection**
(configuration: AnyConfigurationModel, initialSnapshot?: object) => any | |
| **breakConnection**
(configuration: AnyConfigurationModel) => void | Remove a live connection instance. Tolerant of an already-dormant connection (its instance is stripped from the session on reload). Leaves persisted open-track configs alone — the connect() error path calls this and the user's already-open tracks must survive a transient failure. Full removal goes through `deleteConnection`. |
| **teardownConnection**
(configuration: AnyConfigurationModel) => void | Close every track a connection contributed — the live instance's tracks plus any persisted open-track configs (a dormant connection, never expanded this session, still renders its opened tracks from `connectionTrackConfigs`) — from all views/widgets, drop the live instance, and drop the persisted configs. The session is left as if the connection had never loaded. |
| **deleteConnection**
(configuration: AnyConfigurationModel) => any | Fully remove a connection: tear down its tracks and live instance, then delete its config. |
| **addConnectionConf**
(connectionConf: AnyConfiguration) => any | Adds to the **config**, not the session: `jbrowse.connections`, which every visitor to this instance loads. jbrowse-web overrides this so a non-admin's connection lands in `sessionConnections` instead — see WebSessionConnectionsMixin, whose `addSessionConnectionConf` is what to call when you mean the session specifically rather than "wherever this user's edits go".
Applications without that override (Desktop, the embedded products) have only this one destination, and it is the right one there: their config and session are saved as a single document. |
| **clearConnections**
() => void | |
| **captureConnectionTrack**
(trackId: string) => void | Snapshot a just-opened connection track's config into `connectionTrackConfigs` so it survives session reload. No-op if the track isn't connection-provided or is already captured (edits go through `updateConnectionTrackConfig`). |
| **updateConnectionTrackConfig**
(trackConf: Record<string, unknown> & { trackId: string; }) => void | Persist an edit to an opened connection track. The full config is stored (not a delta): the connection's fetched "base" isn't present at load, so only a complete config resolves synchronously. |
| **setConnectionTrackConfig**
(trackId: string, connectionId: string, config: Record<string, unknown>) => void | Upsert one opened connection track's persisted config. |
| **pruneConnectionTrackConfig**
(trackId: string) => void | Drop a connection track's persisted config once no open view still references it, so the session doesn't accumulate closed tracks. |
| **hydrateConnection**
(connectionId: string) => void | Lazily establish a single connection by id if it isn't already live; the track selector calls it when the connection's category is expanded. Fetches without launching a view or showing a success snackbar; already-open tracks keep rendering from `connectionTrackConfigs` meanwhile. Idempotent. |