Listens to changes. This method is only available via gRPC or WebChannel (not REST).

Scopes

You will need authorization for at least one of the following scopes to make a valid call:

https://www.googleapis.com/auth/cloud-platform
https://www.googleapis.com/auth/datastore

If unset, the scope for this method defaults to https://www.googleapis.com/auth/cloud-platform. You can set the scope for this method like this: firestore1-beta1 --scope <scope> projects databases-documents-listen ...

Required Scalar Argument

<database> (string)
- Required. The database name. In the format: projects/{project_id}/databases/{database_id}.

Required Request Value

The request value is a data-structure with various fields. Each field may be a simple scalar or another data-structure. In the latter case it is advised to set the field-cursor to the data-structure's field to specify values more concisely.

For example, a structure like this:

ListenRequest:
  add-target:
    documents:
      documents: [string]
    expected-count: integer
    once: boolean
    query:
      parent: string
      structured-query:
        end-at:
          before: boolean
        limit: integer
        offset: integer
        start-at:
          before: boolean
        where:
          composite-filter:
            op: string
          field-filter:
            field:
              field-path: string
            op: string
            value:
              boolean-value: boolean
              bytes-value: string
              double-value: number
              geo-point-value:
                latitude: number
                longitude: number
              integer-value: string
              null-value: string
              reference-value: string
              string-value: string
              timestamp-value: string
          unary-filter:
            field:
              field-path: string
            op: string
    read-time: string
    resume-token: string
    target-id: integer
  labels: { string: string }
  remove-target: integer

can be set completely with the following arguments which are assumed to be executed in the given order. Note how the cursor position is adjusted to the respective structures, allowing simple field names to be used most of the time.

-r .add-target.documents documents=eos
- The names of the documents to retrieve. In the format: projects/{project_id}/databases/{database_id}/documents/{document_path}. The request will fail if any of the document is not a child resource of the given database. Duplicate names will be elided.
- Each invocation of this argument appends the given value to the array.
.. expected-count=97
- The number of documents that last matched the query at the resume token or read time. This value is only relevant when a resume_type is provided. This value being present and greater than zero signals that the client wants ExistenceFilter.unchanged_names to be included in the response.
once=true
- If the target should be removed once it is current and consistent.
query parent=invidunt
- The parent resource name. In the format: projects/{project_id}/databases/{database_id}/documents or projects/{project_id}/databases/{database_id}/documents/{document_path}. For example: projects/my-project/databases/my-database/documents or projects/my-project/databases/my-database/documents/chatrooms/my-chatroom
structured-query.end-at before=true
- If the position is just before or just after the given values, relative to the sort order defined by the query.
.. limit=81
- The maximum number of results to return. Applies after all other constraints. Requires: * The value must be greater than or equal to zero if specified.
offset=51
- The number of documents to skip before returning the first result. This applies after the constraints specified by the WHERE, START AT, & END AT but before the LIMIT clause. Requires: * The value must be greater than or equal to zero if specified.
start-at before=false
- If the position is just before or just after the given values, relative to the sort order defined by the query.
..where.composite-filter op=ut
- The operator for combining multiple filters.
..field-filter.field field-path=gubergren
- A reference to a field in a document. Requires: * MUST be a dot-delimited (.) string of segments, where each segment conforms to document field name limitations.
.. op=rebum.
- The operator to filter by.
value boolean-value=true
- A boolean value.
bytes-value=ipsum
- A bytes value. Must not exceed 1 MiB - 89 bytes. Only the first 1,500 bytes are considered by queries.
double-value=0.4033695817113857
- A double value.
geo-point-value latitude=0.737544430792817
- The latitude in degrees. It must be in the range [-90.0, +90.0].
longitude=0.3108500366192227
- The longitude in degrees. It must be in the range [-180.0, +180.0].
.. integer-value=dolor
- An integer value.
null-value=lorem
- A null value.
reference-value=eos
- A reference to a document. For example: projects/{project_id}/databases/{database_id}/documents/{document_path}.
string-value=labore
- A string value. The string, represented as UTF-8, must not exceed 1 MiB - 89 bytes. Only the first 1,500 bytes of the UTF-8 representation are considered by queries.
timestamp-value=sed
- A timestamp value. Precise only to microseconds. When stored, any additional precision is rounded down.
...unary-filter.field field-path=duo
- A reference to a field in a document. Requires: * MUST be a dot-delimited (.) string of segments, where each segment conforms to document field name limitations.
.. op=sed
- The unary operator to apply.
..... read-time=no
- Start listening after a specific read_time. The client must know the state of matching documents at this time.
resume-token=stet
- A resume token from a prior TargetChange for an identical target. Using a resume token with a different target is unsupported and may fail.
target-id=88
- The target ID that identifies the target on the stream. Must be a positive number and non-zero. If target_id is 0 (or unspecified), the server will assign an ID for this target and return that in a TargetChange::ADD event. Once a target with target_id=0 is added, all subsequent targets must also have target_id=0. If an AddTarget request with target_id != 0 is sent to the server after a target with target_id=0 is added, the server will immediately send a response with a TargetChange::Remove event. Note that if the client sends multiple AddTarget requests without an ID, the order of IDs returned in TargetChage.target_ids are undefined. Therefore, clients should provide a target ID instead of relying on the server to assign one. If target_id is non-zero, there must not be an existing active target on this stream with the same ID.
.. labels=key=et
- Labels associated with this target change.
- the value will be associated with the given key
remove-target=58
- The ID of a target to remove from this stream.

About Cursors

The cursor position is key to comfortably set complex nested structures. The following rules apply:

The cursor position is always set relative to the current one, unless the field name starts with the . character. Fields can be nested such as in -r f.s.o .
The cursor position is set relative to the top-level structure if it starts with ., e.g. -r .s.s
You can also set nested fields without setting the cursor explicitly. For example, to set a value relative to the current cursor position, you would specify -r struct.sub_struct=bar.
You can move the cursor one level up by using ... Each additional . moves it up one additional level. E.g. ... would go three levels up.

Optional Output Flags

The method's return value a JSON encoded structure, which will be written to standard output by default.

-o out
- out specifies the destination to which to write the server's result to. It will be a JSON-encoded structure. The destination may be - to indicate standard output, or a filepath that is to contain the received bytes. If unset, it defaults to standard output.

Optional General Properties

The following properties can configure any call, and are not specific to this method.

-p $-xgafv=string
- V1 error format.
-p access-token=string
- OAuth access token.
-p alt=string
- Data format for response.
-p callback=string
- JSONP
-p fields=string
- Selector specifying which fields to include in a partial response.
-p key=string
- API key. Your API key identifies your project and provides you with API access, quota, and reports. Required unless you provide an OAuth 2.0 token.
-p oauth-token=string
- OAuth 2.0 token for the current user.
-p pretty-print=boolean
- Returns response with indentations and line breaks.
-p quota-user=string
- Available to use for quota purposes for server-side applications. Can be any arbitrary string assigned to a user, but should not exceed 40 characters.
-p upload-type=string
- Legacy upload protocol for media (e.g. "media", "multipart").
-p upload-protocol=string
- Upload protocol for media (e.g. "raw", "multipart").