Get bibliographic records from OpenAlex database

`oa_request` makes a request and downloads bibliographic records from OpenAlex database https://openalex.org/. The function oa_request queries OpenAlex database using a query formulated through the function oa_query.

Usage

oa_request(
  query_url,
  per_page = 200,
  count_only = FALSE,
  mailto = oa_email(),
  verbose = FALSE
)

Arguments

query_url: Character string. A search query formulated using the OpenAlex API language and can be generated with oa_query.
per_page: Numeric. Number of items to download per page. The per-page argument can assume any number between 1 and 200. Defaults to 200.
count_only: Logical. If TRUE, the function returns only the number of item matching the query. Defaults to FALSE.
mailto: Character string. Gives OpenAlex an email to enter the polite pool.
verbose: Logical. If TRUE, print information about the querying process. Defaults to TRUE.

Value

a data.frame or a list of bibliographic records.

For more extensive information about OpenAlex API, please visit: <https://docs.openalex.org>

Examples

if (FALSE) {

### EXAMPLE 1: Full record about an entity.

# Query to obtain all information about a particular work/author/institution/etc.:

#  The following paper is associated to the OpenAlex-id W2755950973.

#  Aria, M., & Cuccurullo, C. (2017). bibliometrix:
#   An R-tool for comprehensive science mapping analysis.
#   Journal of informetrics, 11(4), 959-975.


query_work <- oa_query(
  identifier = "W2755950973",
  entity = "works",
  endpoint = "https://api.openalex.org"
)

res <- oa_request(
  query_url = query_work,
  count_only = FALSE,
  verbose = FALSE
)

#  The author Massimo Aria is associated to the OpenAlex-id A923435168.


query_author <- oa_query(
  identifier = "A923435168",
  entity = "authors",
  endpoint = "https://api.openalex.org"
)

res <- oa_request(
  query_url = query_author,
  count_only = FALSE,
  verbose = FALSE
)



### EXAMPLE 2: all works citing a particular work.

# Query to search all works citing the article:
#  Aria, M., & Cuccurullo, C. (2017). bibliometrix:
#   An R-tool for comprehensive science mapping analysis.
#   Journal of informetrics, 11(4), 959-975.

#  published in 2021.
#  The paper is associated to the OpenAlex id W2755950973.

#  Results have to be sorted by relevance score in a descending order.

query2 <- oa_query(
  identifier = NULL,
  entity = "works",
  filter = "cites:W2755950973",
  from_publication_date = "2021-01-01",
  to_publication_date = "2021-12-31",
  search = NULL,
  endpoint = "https://api.openalex.org"
)

res2 <- oa_request(
  query_url = query2,
  count_only = FALSE,
  verbose = FALSE
)

### EXAMPLE 3: All works matching a string in their title

# Query to search all works containing the exact string
# "bibliometric analysis" OR "science mapping" in the title, published in 2020 or 2021.

# Results have to be sorted by relevance score in a descending order.


query3 <- oa_query(
  identifier = NULL,
  entity = "works",
  filter = 'title.search:"bibliometric analysis"|"science mapping"',
  from_publication_date = "2020-01-01",
  to_publication_date = "2021-12-31",
  search = NULL,
  endpoint = "https://api.openalex.org"
)

res3 <- oa_request(
  query_url = query3,
  count_only = FALSE,
  verbose = FALSE
)

### EXAMPLE 4: How to check how many works match a query
# Query to search all works containing the exact string
# "bibliometric analysis" OR "science mapping" in the title, published in 2020 or 2021.

# Query only to know how many works could be retrieved (count_only=TRUE)

query4 <- oa_query(
  identifier = NULL,
  entity = "works",
  filter = 'title.search:"bibliometric analysis"|"science mapping"',
  from_publication_date = "2020-01-01",
  to_publication_date = "2021-12-31",
  search = NULL,
  endpoint = "https://api.openalex.org"
)

res4 <- oa_request(
  query_url = query4,
  count_only = TRUE,
  verbose = FALSE
)

res4$count # number of items retrieved by our query
}