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galah (version 2.2.0)

compute.data_request: Compute a query

Description

Sends a request for information to a server. This is useful for requests that run a server-side process, as it separates the submission of the request from its retrieval.

Within galah, compute() is generally hidden as it is one part of the overall process to complete a data_request, metadata_request or file_request. However, calling compute() at the end of a galah_call() sends a request to be completed server-side (i.e., outside of R), and the result can be returned in R by calling collect() at a later time. This can be preferable to calling atlas_occurrences(), which prevents execution of new code until the server-side process is complete.

Usage

# S3 method for data_request
compute(x, ...)

# S3 method for metadata_request compute(x, ...)

# S3 method for files_request compute(x, ...)

# S3 method for prequery compute(x, ...)

# S3 method for query compute(x, ...)

# S3 method for query_set compute(x, ...)

Value

An object of class computed_query, which is identical to class query except for occurrence data, where it also contains information on the status of the request.

Arguments

x

An object of class data_request, metadata_request or files_request (i.e. constructed using a pipe) or query (i.e. constructed by collapse())

...

Arguments passed on to other methods

Details

galah uses an object-based pipeline to convert piped requests into valid queries, and to enact those queries with the specified organisation. Typically, requests open with galah_call() - though request_metadata() and request_files() are also valid - and end with collect(). Under the hood, the sequence of functions is as follows:

capture()compound()collapse()compute()collect()

compute() sends a query to a server, which, once completed, can be retrieved using collect().

See Also

To open a piped query, see galah_call(). For alternative operations on _request objects, see capture(), compound(), collapse(), collect().