Class: Google::Cloud::Firestore::Transaction

Inherits:
Object
  • Object
show all
Defined in:
lib/google/cloud/firestore/transaction.rb

Overview

Transaction

A transaction in Cloud Firestore is a set of reads and writes that execute atomically at a single logical point in time.

All changes are accumulated in memory until the block passed to Database#transaction completes. Transactions will be automatically retried when documents change before the transaction is committed. See Database#transaction.

Examples:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

city = firestore.col("cities").doc("SF")
city.set({ name: "San Francisco",
           state: "CA",
           country: "USA",
           capital: false,
           population: 860000 })

firestore.transaction do |tx|
  new_population = tx.get(city).data[:population] + 1
  tx.update(city, { population: new_population })
end

Access collapse

Modifications collapse

Instance Method Summary collapse

Instance Method Details

#create(doc, data) ⇒ Object

Creates a document with the provided data (fields and values).

The operation will fail if the document already exists.

Examples:

Create a document using a document path:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  tx.create("cities/NYC", { name: "New York City" })
end

Create a document using a document reference:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

firestore.transaction do |tx|
  tx.create(nyc_ref, { name: "New York City" })
end

Create a document and set a field to server_time:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

firestore.transaction do |tx|
  tx.create(nyc_ref, { name: "New York City",
                       updated_at: firestore.field_server_time })
end

Parameters:

  • doc (String, DocumentReference) —

    A string representing the path of the document, or a document reference object.

  • data (Hash) —

    The document's fields and values.



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# File 'lib/google/cloud/firestore/transaction.rb', line 285

def create doc, data
  ensure_not_closed!

  doc_path = coalesce_doc_path_argument doc

  @writes << Convert.writes_for_create(doc_path, data)

  nil
end

#delete(doc, exists: nil, update_time: nil) ⇒ Object

Deletes a document from the database.

Examples:

Delete a document using a document path:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  # Delete a document
  tx.delete "cities/NYC"
end

Delete a document using a document reference:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

firestore.transaction do |tx|
  # Delete a document
  tx.delete nyc_ref
end

Delete a document using exists:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  # Delete a document
  tx.delete "cities/NYC", exists: true
end

Delete a document using the update_time precondition:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

last_updated_at = Time.now - 42 # 42 seconds ago

firestore.transaction do |tx|
  # Delete a document
  tx.delete "cities/NYC", update_time: last_updated_at
end

Parameters:

  • doc (String, DocumentReference) —

    A string representing the path of the document, or a document reference object.

  • exists (Boolean) —

    Whether the document must exist. When true, the document must exist or an error is raised. Default is false. Optional.

  • update_time (Time) —

    When set, the document must have been last updated at that time. Optional.



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# File 'lib/google/cloud/firestore/transaction.rb', line 559

def delete doc, exists: nil, update_time: nil
  ensure_not_closed!

  doc_path = coalesce_doc_path_argument doc

  @writes << Convert.write_for_delete(
    doc_path, exists: exists, update_time: update_time)

  nil
end

#firestore ⇒ Client Also known as: client

The client the Cloud Firestore transaction belongs to.

Returns:

  • (Client) —

    firestore client.



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# File 'lib/google/cloud/firestore/transaction.rb', line 74

def firestore
  @client
end

#get(obj) {|documents| ... } ⇒ DocumentReference, Enumerator<DocumentReference> Also known as: run

Retrieves document snapshots for the given value. Valid values can be a string representing either a document or a collection of documents, a document reference object, a collection reference object, or a query to be run.

Examples:

Get a document snapshot given a document path:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  # Get a document snapshot
  nyc_snap = tx.get "cities/NYC"
end

Get a document snapshot given a document reference:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

firestore.transaction do |tx|
  # Get a document snapshot
  nyc_snap = tx.get nyc_ref
end

Get document snapshots given a collection path:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  # Get documents for a collection path
  tx.get("cities").each do |city|
    # Update the city population by 1
    tx.update(city, { population: city[:population] + 1})
  end
end

Get document snapshots given a collection reference:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a collection reference
cities_col = firestore.col :cities

firestore.transaction do |tx|
  # Get documents for a collection
  tx.get(cities_col).each do |city|
    # Update the city population by 1
    tx.update(city, { population: city[:population] + 1})
  end
end

Get document snapshots given a query:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Create a query
query = firestore.col(:cities).select(:population)

firestore.transaction do |tx|
  # Get/run a query
  tx.get(query).each do |city|
    # Update the city population by 1
    tx.update(city, { population: city[:population] + 1})
  end
end

Parameters:

Yields:

  • (documents) —

    The block for accessing the document snapshots.

Yield Parameters:

Returns:

  • (DocumentReference, Enumerator<DocumentReference>) —

    A single document snapshot when passed a document path a document reference, or a list of document snapshots when passed other valid values.



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# File 'lib/google/cloud/firestore/transaction.rb', line 214

def get obj
  ensure_not_closed!
  ensure_service!

  obj = coalesce_get_argument obj

  if obj.is_a?(DocumentReference)
    doc = get_all([obj]).first
    yield doc if block_given?
    return doc
  end

  return enum_for(:get, obj) unless block_given?

  results = service.run_query obj.parent_path, obj.query,
                              transaction: transaction_or_create
  results.each do |result|
    extract_transaction_from_result! result
    next if result.document.nil?
    yield DocumentSnapshot.from_query_result(result, self)
  end
end

#get_all(*docs) {|documents| ... } ⇒ Enumerator<DocumentSnapshot> Also known as: get_docs, get_documents, find

Retrieves a list of document snapshots.

Examples:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  # Get and print city documents
  tx.get_all("cities/NYC", "cities/SF", "cities/LA").each do |city|
    puts "#{city.document_id} has #{city[:population]} residents."
  end
end

Parameters:

  • docs (String, DocumentReference) —

    One or more strings representing the path of the document, or document reference objects.

Yields:

  • (documents) —

    The block for accessing the document snapshots.

Yield Parameters:

Returns:



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# File 'lib/google/cloud/firestore/transaction.rb', line 105

def get_all *docs
  ensure_not_closed!
  ensure_service!

  return enum_for(:get_all, docs) unless block_given?

  doc_paths = Array(docs).flatten.map do |doc_path|
    coalesce_doc_path_argument doc_path
  end

  results = service.get_documents \
    doc_paths, transaction: transaction_or_create
  results.each do |result|
    extract_transaction_from_result! result
    next if result.result.nil?
    yield DocumentSnapshot.from_batch_result(result, self)
  end
end

#set(doc, data, merge: nil) ⇒ Object

Writes the provided data (fields and values) to the provided document. If the document does not exist, it will be created. By default, the provided data overwrites existing data, but the provided data can be merged into the existing document using the merge argument.

If you're not sure whether the document exists, use the merge argument to merge the new data with any existing document data to avoid overwriting entire documents.

Examples:

Set a document using a document path:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  # Update a document
  tx.set("cities/NYC", { name: "New York City" })
end

Create a document using a document reference:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

firestore.transaction do |tx|
  # Update a document
  tx.set(nyc_ref, { name: "New York City" })
end

Set a document and merge all data:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  tx.set("cities/NYC", { name: "New York City" }, merge: true)
end

Set a document and merge only name:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  tx.set("cities/NYC", { name: "New York City" }, merge: :name)
end

Set a document and deleting a field using merge:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

nyc_data = { name: "New York City",
             trash: firestore.field_delete }

firestore.transaction do |tx|
  tx.set(nyc_ref, nyc_data, merge: true)
end

Set a document and set a field to server_time:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

nyc_data = { name: "New York City",
             updated_at: firestore.field_server_time }

firestore.transaction do |tx|
  tx.set(nyc_ref, nyc_data, merge: true)
end

Parameters:

  • doc (String, DocumentReference) —

    A string representing the path of the document, or a document reference object.

  • data (Hash) —

    The document's fields and values.

  • merge (Boolean, FieldPath, String, Symbol) —

    When true, all provided data is merged with the existing document data. When the argument is one or more field path, only the data for fields in this argument is merged with the existing document data. The default is to not merge, but to instead overwrite the existing document data.



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# File 'lib/google/cloud/firestore/transaction.rb', line 386

def set doc, data, merge: nil
  ensure_not_closed!

  doc_path = coalesce_doc_path_argument doc

  @writes << Convert.writes_for_set(doc_path, data, merge: merge)

  nil
end

#transaction_id ⇒ String

The transaction identifier.

Returns:

  • (String) —

    transaction identifier.



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# File 'lib/google/cloud/firestore/transaction.rb', line 66

def transaction_id
  @transaction_id
end

#update(doc, data, update_time: nil) ⇒ Object

Updates the document with the provided data (fields and values). The provided data is merged into the existing document data.

The operation will fail if the document does not exist.

Examples:

Update a document using a document path:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

firestore.transaction do |tx|
  tx.update("cities/NYC", { name: "New York City" })
end

Directly update a deeply-nested field with a FieldPath:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

nested_field_path = Google::Cloud::Firestore::FieldPath.new(
  :favorites, :food
)

firestore.transaction do |tx|
  tx.update("users/frank", { nested_field_path: "Pasta" })
end

Update a document using a document reference:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

firestore.transaction do |tx|
  tx.update(nyc_ref, { name: "New York City" })
end

Update a document using the update_time precondition:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

last_updated_at = Time.now - 42 # 42 seconds ago

firestore.transaction do |tx|
  tx.update("cities/NYC", { name: "New York City" },
           update_time: last_updated_at)
end

Update a document and deleting a field:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

nyc_data = { name: "New York City",
             trash: firestore.field_delete }

firestore.transaction do |tx|
  tx.update(nyc_ref, nyc_data)
end

Update a document and set a field to server_time:

require "google/cloud/firestore"

firestore = Google::Cloud::Firestore.new

# Get a document reference
nyc_ref = firestore.doc "cities/NYC"

nyc_data = { name: "New York City",
             updated_at: firestore.field_server_time }

firestore.transaction do |tx|
  tx.update(nyc_ref, nyc_data)
end

Parameters:

  • doc (String, DocumentReference) —

    A string representing the path of the document, or a document reference object.

  • data (Hash<FieldPath|String|Symbol, Object>) —

    The document's fields and values.

    The top-level keys in the data hash are considered field paths, and can either be a FieldPath object, or a string representing the nested fields. In other words the string represents individual fields joined by ".". Fields containing ~, *, /, [, ], and . cannot be in a dotted string, and should provided using a FieldPath object instead.

  • update_time (Time) —

    When set, the document must have been last updated at that time. Optional.



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# File 'lib/google/cloud/firestore/transaction.rb', line 492

def update doc, data, update_time: nil
  ensure_not_closed!

  doc_path = coalesce_doc_path_argument doc

  @writes << Convert.writes_for_update(doc_path, data,
                                       update_time: update_time)

  nil
end