#Obviously these need to be installed!
library(jsonlite)
library(tm)
library(wordcloud)

files <- list.files('.',"*.json", recursive=T)

json <- sapply(files, fromJSON)

texts <- sapply(json, function(f){if ('subtype' %in% names(f)) f$text[is.na(f$subtype)] else f$text})

flat <- unlist(texts)

corpus <- Corpus(VectorSource(flat))
corpus <- tm_map(corpus, stripWhitespace)
corpus <- tm_map(corpus, tolower)
corpus <- tm_map(corpus, removePunctuation)
corpus <- tm_map(corpus, removeNumbers)
corpus <- tm_map(corpus, removeWords, stopwords('english'))
#remove words slack adds
corpus1 <- tm_map(corpus, removeWords, c('UZDP', 'UULQF', 'UKZS','UCNJ', 'UUJX','UULQF'))

wordcloud(corpus1, scale=c(2.5,0.5), max.words=1000, random.order=FALSE, rot.per=0.35, use.r.layout=FALSE, colors=brewer.pal(8, "Dark2"))