singer_sdk.RESTStream
- class singer_sdk.RESTStream
Abstract base class for REST API streams.
- __init__(tap: TapBaseClass, name: str | None = None, schema: dict[str, Any] | Schema | None = None, path: str | None = None) None
Initialize the REST stream.
- Parameters
tap – Singer Tap this stream belongs to.
schema – JSON schema for records in this stream.
name – Name of this stream.
path – URL path for this entity stream.
- property authenticator: APIAuthenticatorBase | None
Return or set the authenticator for managing HTTP auth headers.
If an authenticator is not specified, REST-based taps will simply pass http_headers as defined in the stream class.
- Returns
Authenticator instance that will be used to authenticate all outgoing requests.
- backoff_handler(details: Details) None
Adds additional behaviour prior to retry.
By default will log out backoff details, developers can override to extend or change this behaviour.
- Parameters
details – backoff invocation details https://github.com/litl/backoff#event-handlers
- backoff_max_tries() int
The number of attempts before giving up when retrying requests.
- Returns
Number of max retries.
- backoff_runtime(*, value: Callable[[Any], int]) Generator[int, None, None]
Optional backoff wait generator that can replace the default backoff.expo.
It is based on parsing the thrown exception of the decorated method, making it possible for response values to be in scope.
- Parameters
value – a callable which takes as input the decorated function’s thrown exception and determines how long to wait.
- Yields
The thrown exception
- backoff_wait_generator() Generator[float, None, None]
The wait generator used by the backoff decorator on request failure.
See for options: https://github.com/litl/backoff/blob/master/backoff/_wait_gen.py
And see for examples: Code Samples
- Returns
The wait generator
- build_prepared_request(*args: Any, **kwargs: Any) PreparedRequest
Build a generic but authenticated request.
Uses the authenticator instance to mutate the request with authentication.
- Parameters
*args – Arguments to pass to requests.Request.
**kwargs – Keyword arguments to pass to requests.Request.
- Returns
A requests.PreparedRequest object.
- calculate_sync_cost(request: requests.PreparedRequest, response: requests.Response, context: dict | None) dict[str, int]
Calculate the cost of the last API call made.
This method can optionally be implemented in streams to calculate the costs (in arbitrary units to be defined by the tap developer) associated with a single API/network call. The request and response objects are available in the callback, as well as the context.
The method returns a dict where the keys are arbitrary cost dimensions, and the values the cost along each dimension for this one call. For instance: { “rest”: 0, “graphql”: 42 } for a call to github’s graphql API. All keys should be present in the dict.
This method can be overridden by tap streams. By default it won’t do anything.
- Parameters
request – the API Request object that was just called.
response – the requests.Response object
context – the context passed to the call
- Returns
A dict of accumulated costs whose keys are the “cost domains”.
- extra_retry_statuses: list[int] = [429]
Response code reference for rate limit retries
- get_new_paginator() BaseAPIPaginator
Get a fresh paginator for this API endpoint.
- Returns
A paginator instance.
- get_records(context: dict | None) Iterable[dict[str, Any]]
Return a generator of record-type dictionary objects.
Each record emitted should be a dictionary of property names to their values.
- Parameters
context – Stream partition or context dictionary.
- Yields
One item per (possibly processed) record in the API.
- get_url(context: dict | None) str
Get stream entity URL.
Developers override this method to perform dynamic URL generation.
- Parameters
context – Stream partition or context dictionary.
- Returns
A URL, optionally targeted to a specific partition or context.
- get_url_params(context: dict | None, next_page_token: _TToken | None) dict[str, Any]
Return a dictionary of values to be used in URL parameterization.
If paging is supported, developers may override with specific paging logic.
- Parameters
context – Stream partition or context dictionary.
next_page_token – Token, page number or any request argument to request the next page of data.
- Returns
Dictionary of URL query parameters to use in the request.
- property http_headers: dict
Return headers dict to be used for HTTP requests.
If an authenticator is also specified, the authenticator’s headers will be combined with http_headers when making HTTP requests.
- Returns
Dictionary of HTTP headers to use as a base for every request.
- next_page_token_jsonpath: str | None = None
Optional JSONPath expression to extract a pagination token from the API response. Example: “$.next_page”
- parse_response(response: Response) Iterable[dict]
Parse the response and return an iterator of result records.
- Parameters
response – A raw requests.Response object.
- Yields
One item for every item found in the response.
- prepare_request(context: dict | None, next_page_token: _TToken | None) requests.PreparedRequest
Prepare a request object for this stream.
If partitioning is supported, the context object will contain the partition definitions. Pagination information can be parsed from next_page_token if next_page_token is not None.
- Parameters
context – Stream partition or context dictionary.
next_page_token – Token, page number or any request argument to request the next page of data.
- Returns
Build a request with the stream’s URL, path, query parameters, HTTP headers and authenticator.
- prepare_request_payload(context: dict | None, next_page_token: _TToken | None) dict | None
Prepare the data payload for the REST API request.
By default, no payload will be sent (return None).
Developers may override this method if the API requires a custom payload along with the request. (This is generally not required for APIs which use the HTTP ‘GET’ method.)
- Parameters
context – Stream partition or context dictionary.
next_page_token – Token, page number or any request argument to request the next page of data.
- Returns
Dictionary with the body to use for the request.
- records_jsonpath: str = '$[*]'
JSONPath expression to extract records from the API response.
- request_decorator(func: Callable) Callable
Instantiate a decorator for handling request failures.
Uses a wait generator defined in backoff_wait_generator to determine backoff behaviour. Try limit is defined in backoff_max_tries, and will trigger the event defined in backoff_handler before retrying. Developers may override one or all of these methods to provide custom backoff or retry handling.
- Parameters
func – Function to decorate.
- Returns
A decorated method.
- request_records(context: dict | None) Iterable[dict]
Request records from REST endpoint(s), returning response records.
If pagination is detected, pages will be recursed automatically.
- Parameters
context – Stream partition or context dictionary.
- Yields
An item for every record in the response.
- property requests_session: Session
Get requests session.
- Returns
The requests.Session object for HTTP requests.
- response_error_message(response: Response) str
Build error message for invalid http statuses.
WARNING - Override this method when the URL path may contain secrets or PII
- Parameters
response – A requests.Response object.
- Returns
The error message
- Return type
str
- property timeout: int
Return the request timeout limit in seconds.
The default timeout is 300 seconds, or as defined by DEFAULT_REQUEST_TIMEOUT.
- Returns
The request timeout limit as number of seconds.
- update_sync_costs(request: requests.PreparedRequest, response: requests.Response, context: dict | None) dict[str, int]
Update internal calculation of Sync costs.
- Parameters
request – the Request object that was just called.
response – the requests.Response object
context – the context passed to the call
- Returns
A dict of costs (for the single request) whose keys are the “cost domains”. See calculate_sync_cost for details.
- abstract property url_base: str
Return the base url, e.g.
https://api.mysite.com/v3/
.
- validate_response(response: Response) None
Validate HTTP response.
Checks for error status codes and wether they are fatal or retriable.
In case an error is deemed transient and can be safely retried, then this method should raise an
singer_sdk.exceptions.RetriableAPIError
. By default this applies to 5xx error codes, along with values set in:extra_retry_statuses
In case an error is unrecoverable raises a
singer_sdk.exceptions.FatalAPIError
. By default, this applies to 4xx errors, excluding values found in:extra_retry_statuses
Tap developers are encouraged to override this method if their APIs use HTTP status codes in non-conventional ways, or if they communicate errors differently (e.g. in the response body).
- Parameters
response – A requests.Response object.
- Raises
FatalAPIError – If the request is not retriable.
RetriableAPIError – If the request is retriable.