add geojson support. not finished

DESCRIPTION

@@ -9,22 +9,23 @@ Description: Provides easier interaction with
     returns an R data frame.
     Converts dates to 'POSIX' format.
     Manages throttling by 'Socrata'.
+    Supports geospacial data (GeoJSON).
 Version: 1.6.3
 Date: 2015-07-23
 Author: Hugh Devlin, Ph. D., Tom Schenk, Jr., and John Malc
 Maintainer: "Tom Schenk Jr." <developers@cityofchicago.org>
 Depends: 
-    R (>= 3.0.0)
+    R (>= 3.2.0)
 Imports: 
     httr (>= 1.0.0),
     jsonlite (>= 0.9.16),
-    mime (>= 0.3)
+    mime (>= 0.3), 
+    geojsonio (>= 0.1.0)
 Suggests: 
     testthat (>= 0.10.0),
     roxygen2 (>= 4.1.0),
     knitr (>= 1.10.5), 
-    leaflet (>= 1.0.0), 
-    geojsonio (>= 0.1.0)
+    leaflet (>= 1.0.0)
 License: MIT + file LICENSE
 URL: https://github.com/Chicago/RSocrata
 BugReports: https://github.com/Chicago/RSocrata/issues

NAMESPACE

@@ -6,6 +6,7 @@ export(ls.socrata)
 export(posixify)
 export(read.socrata)
 export(validateUrl)
+importFrom(geojsonio,geojson_read)
 importFrom(httr,GET)
 importFrom(httr,build_url)
 importFrom(httr,content)

R/returnData.R

@@ -4,9 +4,10 @@
 # Author: Hugh J. Devlin, Ph. D. 2013-08-28
 ###############################################################################
 
-# library('httr')       # for access to the HTTP header
-# library('jsonlite')   # for parsing data types from Socrata
-# library('mime')       # for guessing mime type
+# library("httr")       # for access to the HTTP header
+# library("jsonlite")   # for parsing data types from Socrata
+# library("mime")       # for guessing mime type
+# library("geojsonio") # for geospatial json
 
 #' Wrap httr GET in some diagnostics
 #' 
@@ -32,6 +33,7 @@ checkResponse <- function(url = "") {
 #'
 #' @author Hugh J. Devlin \email{Hugh.Devlin@@cityofchicago.org}
 #' @importFrom httr content
+#' @importFrom geojsonio geojson_read
 #' @param response - an httr response object
 #' @return data frame, possibly empty
 #' @noRd
@@ -47,14 +49,16 @@ getContentAsDataFrame <- function(response) {
   }
 
   switch(mimeType,
-         'text/csv' = 
+         "text/csv" = 
            httr::content(response), # automatic parsing
-         'application/json' = 
-           if(httr::content(response, as = 'text') == "[ ]") { # empty json?
+         "application/json" = 
+           if(httr::content(response, as = "text") == "[ ]") { # empty json?
              data.frame() # empty data frame
            } else {
              data.frame(t(sapply(httr::content(response), unlist)), stringsAsFactors = FALSE)
-           }
+           }, 
+         "application/vnd.geo+json" =  # use geojson_read directly through its response link
+           geojsonio::geojson_read(response$url, method = "local", parse = FALSE, what = "list")
   ) 
 
 }
@@ -76,49 +80,66 @@ getSodaTypes <- function(response) {
 
 #' Get a full Socrata data set as an R data frame
 #'
-#' Manages throttling and POSIX date-time conversions
+#' @description Manages throttling and POSIX date-time conversions.
 #'
-#' @param url - A Socrata resource URL, 
-#' or a Socrata "human-friendly" URL, 
+#' @param url - A Socrata resource URL, or a Socrata "human-friendly" URL, 
 #' or Socrata Open Data Application Program Interface (SODA) query 
 #' requesting a comma-separated download format (.csv suffix), 
-#' May include SoQL parameters, 
-#' but is assumed to not include a SODA offset parameter
-#' @param app_token - a (non-required) string; SODA API token is used to query the data 
+#' May include SoQL parameters, and it is now assumed to include SODA \code{limit} 
+#' & \code{offset} parameters.
+#' Either use a compelete URL, e.g. \code{} or use parameters below to construct your URL. 
+#' But don't combine them.
+#' @param app_token - a (non-required) string; SODA API token can be used to query the data 
 #' portal \url{http://dev.socrata.com/consumers/getting-started.html}
-## @param domain - A Socrata domain, e.g \url{http://data.cityofchicago.org} 
-## @param fourByFour - a unique 4x4 identifier, e.g. "ydr8-5enu". See more \code{\link{isFourByFour}}
-## @param query - Based on query language called the "Socrata Query Language" ("SoQL"), see 
-## \url{http://dev.socrata.com/docs/queries.html}.
-## domain = NULL, fourByFour = NULL, query = NULL, limit = 50000, offset = 0
-## read.socrata(domain = "http://data.cityofchicago.org", fourByFour = "ydr8-5enu", query = "")
-## @section TODO: \url{https://github.com/Chicago/RSocrata/issues/14}
+#' @param domain - A Socrata domain, e.g \url{http://data.cityofchicago.org} 
+#' @param fourByFour - a unique 4x4 identifier, e.g. "ydr8-5enu". See more \code{\link{isFourByFour}}
+#' @param query - Based on query language called the "Socrata Query Language" ("SoQL"), see 
+#' \url{http://dev.socrata.com/docs/queries.html}.
+#' @param limit - defaults to the max of 50000. See \url{http://dev.socrata.com/docs/paging.html}.
+#' @param offset - defaults to the max of 0. See \url{http://dev.socrata.com/docs/paging.html}.
+#' @param output - in case of building URL manually, one of \code{c("csv", "json", "geojson")}
+#' 
+#' @section TODO: \url{https://github.com/Chicago/RSocrata/issues/14}
+#'
 #' @return a data frame with POSIX dates
 #' @author Hugh J. Devlin, Ph. D. \email{Hugh.Devlin@@cityofchicago.org}
+#' 
 #' @examples
 #' df <- read.socrata("http://soda.demo.socrata.com/resource/4334-bgaj.csv")
+#' dfgjs <- read.socrata(url = "https://data.cityofchicago.org/resource/6zsd-86xi.geojson")
+#' df2 <- read.socrata(domain = "http://data.cityofchicago.org", fourByFour = "ydr8-5enu")
+#' 
 #' @importFrom httr parse_url build_url
 #' @importFrom mime guess_type
 #' 
 #' @export
-read.socrata <- function(url, app_token = NULL) {
+read.socrata <- function(url = NULL, app_token = NULL, domain = NULL, fourByFour = NULL, 
+                         query = NULL, limit = 50000, offset = 0, output = NULL) {
+
   # check url syntax, allow human-readable Socrata url
   validUrl <- validateUrl(url, app_token) 
   parsedUrl <- httr::parse_url(validUrl)
-  mimeType <- mime::guess_type(parsedUrl$path)
+  mimeType <- mime::guess_type(parsedUrl$path, unknown = "application/vnd.geo+json")
+
+  # match args
+  output_args <- match.arg(output)
 
-  if(!(mimeType %in% c('text/csv','application/json'))) {
-    stop("Error in read.socrata: ", mimeType, " not a supported data format. Try JSON or CSV.")
+  if(!(mimeType %in% c("text/csv","application/json", "application/vnd.geo+json"))) {
+    stop(mimeType, " not a supported data format. Try JSON, CSV or GeoJSON.")
   }
 
   response <- checkResponse(validUrl)
   page <- getContentAsDataFrame(response)
   result <- page
-  dataTypes <- getSodaTypes(response)
+
+  if(mimeType %in% c("text/csv","application/json")) {
+    dataTypes <- getSodaTypes(response)
+  }
 
   ## More to come? Loop over pages implicitly
+  ## TODO: start here
   while (nrow(page) > 0) { 
-    query_url <- paste0(validUrl, ifelse(is.null(parsedUrl$query), '?', "&"), '$offset=', nrow(result))
+    query_url <- paste0(validUrl, ifelse(is.null(parsedUrl$query), "?", "&"), "$offset=", nrow(result))
     response <- checkResponse(query_url)
     page <- getContentAsDataFrame(response)
     result <- rbind(result, page) # accumulate
@@ -127,7 +148,7 @@ read.socrata <- function(url, app_token = NULL) {
   # Convert Socrata calendar dates to POSIX format
   # Check for column names that are not NA and which dataType is a "calendar_date". If there are some, 
   # then convert them to POSIX format
-  for(columnName in colnames(page)[!is.na(dataTypes[fieldName(colnames(page))]) & dataTypes[fieldName(colnames(page))] == 'calendar_date']) {
+  for(columnName in colnames(page)[!is.na(dataTypes[fieldName(colnames(page))]) & dataTypes[fieldName(colnames(page))] == "calendar_date"]) {
     result[[columnName]] <- posixify(result[[columnName]])
   }
 

man/read.socrata.Rd

@@ -4,27 +4,46 @@
 \alias{read.socrata}
 \title{Get a full Socrata data set as an R data frame}
 \usage{
-read.socrata(url, app_token = NULL)
+read.socrata(url = NULL, app_token = NULL, domain = NULL,
+  fourByFour = NULL, query = NULL, limit = 50000, offset = 0,
+  output = c("csv", "json", "geojson"))
 }
 \arguments{
-\item{url}{- A Socrata resource URL,
-or a Socrata "human-friendly" URL,
+\item{url}{- A Socrata resource URL, or a Socrata "human-friendly" URL,
 or Socrata Open Data Application Program Interface (SODA) query
 requesting a comma-separated download format (.csv suffix),
-May include SoQL parameters,
-but is assumed to not include a SODA offset parameter}
+May include SoQL parameters, and it is now assumed to include SODA \code{limit}
+& \code{offset} parameters.
+Either use a compelete URL, e.g. \code{} or use parameters below to construct your URL.
+But don't combine them.}
 
-\item{app_token}{- a (non-required) string; SODA API token is used to query the data
+\item{app_token}{- a (non-required) string; SODA API token can be used to query the data
 portal \url{http://dev.socrata.com/consumers/getting-started.html}}
+
+\item{domain}{- A Socrata domain, e.g \url{http://data.cityofchicago.org}}
+
+\item{fourByFour}{- a unique 4x4 identifier, e.g. "ydr8-5enu". See more \code{\link{isFourByFour}}}
+
+\item{query}{- Based on query language called the "Socrata Query Language" ("SoQL"), see
+\url{http://dev.socrata.com/docs/queries.html}.}
+
+\item{limit}{- defaults to the max of 50000. See \url{http://dev.socrata.com/docs/paging.html}.}
+
+\item{offset}{- defaults to the max of 0. See \url{http://dev.socrata.com/docs/paging.html}.}
 }
 \value{
 a data frame with POSIX dates
 }
 \description{
-Manages throttling and POSIX date-time conversions
+Manages throttling and POSIX date-time conversions.
+}
+\section{TODO}{
+ \url{https://github.com/Chicago/RSocrata/issues/14}
 }
 \examples{
 df <- read.socrata("http://soda.demo.socrata.com/resource/4334-bgaj.csv")
+dfgjs <- read.socrata(url = "https://data.cityofchicago.org/resource/6zsd-86xi.geojson")
+df2 <- read.socrata(domain = "http://data.cityofchicago.org", fourByFour = "ydr8-5enu")
 }
 \author{
 Hugh J. Devlin, Ph. D. \email{Hugh.Devlin@cityofchicago.org}