man/KorAPConnection-class.Rd

% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/KorAPConnection.R
\docType{class}
\name{KorAPConnection-class}
\alias{KorAPConnection-class}
\alias{KorAPConnection}
\title{Connect to KorAP Server}
\arguments{
\item{KorAPUrl}{URL of the web user interface of the KorAP server instance you want to access.
Defaults to the environment variable \code{KORAP_URL} if set and to the IDS Mannheim KorAP main instance
to query DeReKo, otherwise. In order to access the KorAP instance at the German
National Library (DNB) to query the contemporary fiction corpus DeLiKo@DNB,
for example, set \code{KorAPUrl} to \url{https://korap.dnb.de/}.}

\item{apiVersion}{which version of KorAP's API you want to connect to. Defaults to "v1.0".}

\item{apiUrl}{URL of the KorAP web service. If not provided, it will be constructed from KorAPUrl and apiVersion.}

\item{accessToken}{OAuth2 access token. For queries on corpus parts with restricted
access (e.g. textual queries on IPR protected data), you need to authorize
your application with an access token.
You can obtain an access token in the OAuth settings of your KorAP web interface.

More details are explained in the
\href{https://github.com/KorAP/RKorAPClient#authorization}{authorization section}
of the RKorAPClient Readme on GitHub.

To use authorization based on an access token
in subsequent queries, initialize your KorAP connection with:

\if{html}{\out{<div class="sourceCode">}}\preformatted{kco <- KorAPConnection(accessToken="<access token>")
}\if{html}{\out{</div>}}

In order to make the API
token persistent for the currently used \code{KorAPUrl} (you can have one
token per KorAPUrl / KorAP server instance), use:

\if{html}{\out{<div class="sourceCode">}}\preformatted{persistAccessToken(kco)
}\if{html}{\out{</div>}}

This will store it in your keyring using the
\link[keyring:keyring-package]{keyring::keyring-package}. Subsequent KorAPConnection() calls will
then automatically retrieve the token from your keying. To stop using a
persisted token, call \code{clearAccessToken(kco)}. Please note that for
DeReKo, authorized queries will behave differently inside and outside the
IDS, because of the special license situation. This concerns also cached
results which do not take into account from where a request was issued. If
you experience problems or unexpected results, please try \code{kco <- KorAPConnection(cache=FALSE)} or use
\code{\link[=clearCache]{clearCache()}} to clear the cache completely.

An alternative to using an access token is to use a browser-based oauth2 workflow
to obtain an access token. This can be done with the \code{\link[=auth]{auth()}} method.}

\item{oauthClient}{OAuth2 client object.}

\item{oauthScope}{OAuth2 scope. Defaults to "search match_info".}

\item{authorizationSupported}{logical that indicates if authorization is supported/necessary for the current KorAP instance. Automatically set during initialization.}

\item{userAgent}{user agent string. Defaults to "R-KorAP-Client".}

\item{timeout}{timeout in seconds for API requests (this does not influence server internal timeouts). Defaults to 240 seconds.}

\item{verbose}{logical that decides whether following operations will default to
be verbose. Defaults to FALSE.}

\item{cache}{logical that decides if API calls are cached locally. You can clear
the cache with \code{\link[=clearCache]{clearCache()}}. Defaults to TRUE.}
}
\value{
\code{\link[=KorAPConnection]{KorAPConnection()}} object that can be used e.g. with \code{\link[=corpusQuery]{corpusQuery()}}
}
\description{
\code{KorAPConnection()} creates a connection to a KorAP server for corpus queries.
This is your starting point for all corpus analysis tasks.
}
\details{
Use \code{KorAPConnection()} to connect, then \code{corpusQuery()} to search, and
\code{fetchAll()} to retrieve results. For authorized access to restricted corpora,
use \code{auth()} or provide an \code{accessToken}.

The KorAPConnection object contains various configuration slots for advanced users:
KorAPUrl (server URL), apiVersion, accessToken (OAuth2 token),
timeout (request timeout), verbose (logging), cache (local caching),
and other technical parameters. Most users can ignore these implementation details.
}
\section{Basic Workflow}{


\if{html}{\out{<div class="sourceCode r">}}\preformatted{# Connect to KorAP
kcon <- KorAPConnection()

# Search for a term
query <- corpusQuery(kcon, "Ameisenplage")

# Get all results
results <- fetchAll(query)
}\if{html}{\out{</div>}}
}

\section{Authorization}{

For access to restricted corpora, authorize your connection:

\if{html}{\out{<div class="sourceCode r">}}\preformatted{kcon <- KorAPConnection() |> auth()
}\if{html}{\out{</div>}}
}

\seealso{
Other initialization functions: 
\code{\link{auth,KorAPConnection-method}},
\code{\link{clearAccessToken,KorAPConnection-method}},
\code{\link{persistAccessToken,KorAPConnection-method}}
}
\concept{initialization functions}