Classes

Context

Context

Members

defaultOptions

context.js, line 101

Returns the default options for a db context.

EVENTS

context.js, line 203

All events a context may emit. POST_COMMIT: When a transaction is committed. Do clean up, summery, post process here. TX_FAILED: When a transaction failed permanently (either by failing all retries, or getting a non-retryable error). Handler has the signature of (error) => {}.

Methods

async, static run(optionsopt, func)

context.js, line 594

Runs a function in transaction if needed, using specified parameters. If a non-retryable error is thrown while running the transaction, it will be re-raised.

Parameters:

Name	Type	Attributes	Description
options	ContextOptions	<optional>
func	function		the closure to run.

Example

// Can be called in 2 ways:
Context.run(async (tx) => {
  // Do something
})

// Or
Context.run({ retryCount: 2 }, async (tx) => {
  // Do something
})

create(Cls, data)

context.js, line 421

Creates a model without accessing DB. Write will make sure the doc does not exist.

Parameters:

Name	Type	Description
Cls	Model	A Model class.
data	CompositeID | Object	A superset of CompositeID of the model, plus any data for Fields on the Model.

createOrOverwrite(Cls, data)

context.js, line 434

Sets a model's data. Will overwrite the existing data, if any.

Parameters:

Name	Type	Description
Cls	Model	A Model class.
data	CompositeID | Object	A superset of CompositeID of the model, plus any data for Fields on the Model.

async delete(…args)

context.js, line 448

Deletes model(s) from database. If a model is read from database, but it did not exist when deleting the doc, an exception is raised.

Parameters:

Name	Type	Attributes	Description
args	List.<(Key|Model)>	<repeatable>	Keys and Models

enableModelCache()

context.js, line 500

Enables model cache

async get(Cls, key, paramsopt)

context.js, line 305

Fetches model(s) from database. This method supports 3 different signatures. get(Cls, keyOrDataValues, params) get(Key|Data, params) get([Key|Data], params) Must use a Key when createIfMissing is not true, and Data otherwise. When a list of docs is fetched: Firestore getAll API is called. Batched fetches are more efficient than calling get with 1 key many times, since there is less HTTP request overhead.

Parameters:

Name	Type	Attributes	Description
Cls	Class		a Model class.
key	String | CompositeID		Key or keyValues
params	GetParams	<optional>

Returns:

- Model(s) associated with provided key

getModelDiffs()

context.js, line 608

Return before and after snapshots of all relevant models. Does not include deleted models.

makeReadOnly()

context.js, line 495

Marks a transaction as read-only.

async updateWithoutRead(key, data)

context.js, line 400

Updates an doc without reading from DB. Fails if doc is not in the db.

Parameters:

Name	Type	Description
key	CompositeID	The key to update
data	Object	Updated fields for the doc