Downloaded Facebook data gives me a head ache. It is highly nested (lists of list) and not all lists are equally long. The data should become a flat matrix where one list and its sublists are in one row, i.e. one list including its sublist per row. So far I have explored three options.
Option 1: flatten from purrr
Flattens the data structure but scrambles it. So no way of knowing what text was posted when with what kind of picture. According to the purrr reference manual, I cannot specify an object, e.g. timestamp, by which the lists should be flattened? I am thinking about the reshape2 package that allows to define an ID variable by which the data is reshaped/manipulated.
library(RJSONIO)
#read in data with utf-8 encoding else the German Umlaute won't display
dataRAW <- RJSONIO::fromJSON("C:/***file path***/FB rot 2.json",
encoding = 'utf-8', stringAsFactors = F)
dataRAWflat <- purrr:::flatten(dataRAW) #scrambles data
--> I know that jsonlite has a flatten function when reading in JSON files. But fromJSON from jsonlite does not allow to define the encoding. The encoding needs to be defined else it does not display the German Umlaute correctly. Also tried rjson without success. The text of the posts is key to the project. I spent a good amount of figuring out how to display the Umlaute so happy to help with that :-)
Option 2: unnest_wider from tidyr
Gives an error message saying that it should be numeric or a character, but the list 'data' in dataRAW is a character. New to tibbles as a special kind of dataframe. Do tibbles, like dataframes, need to have equally long columns? What am I missing?
library(tibble)
tib <- tibble(dataRAW)
tib %>% tidyr:::unnest_wider(data)
Error: Must extract column with a single valid subscript.
x Subscript `var` has the wrong type `function`.
i It must be numeric or character.
Run `rlang::last_error()` to see where the error occurred.
> rlang::last_error()
<error/vctrs_error_subscript_type>
Must extract column with a single valid subscript.
x Subscript `var` has the wrong type `function`.
i It must be numeric or character.
Backtrace:
1. tib %>% tidyr:::unnest_wider(data)
2. tidyr:::unnest_wider(., data)
3. tidyselect::vars_pull(tbl_vars(data), !!enquo(col))
4. tidyselect:::pull_as_location2(loc, n, vars)
12. vctrs::vec_as_subscript2(i, arg = "var", logical = "error")
13. vctrs:::result_get(...)
Run `rlang::last_trace()` to see the full context.
> rlang:::last_trace()
<error/vctrs_error_subscript_type>
Must extract column with a single valid subscript.
x Subscript `var` has the wrong type `function`.
i It must be numeric or character.
Backtrace:
x
1. +-tib %>% tidyr:::unnest_wider(data)
2. \-tidyr:::unnest_wider(., data)
3. \-tidyselect::vars_pull(tbl_vars(data), !!enquo(col))
4. \-tidyselect:::pull_as_location2(loc, n, vars)
5. +-tidyselect:::with_subscript_errors(...)
6. | +-base::tryCatch(...)
7. | | \-base:::tryCatchList(expr, classes, parentenv, handlers)
8. | | \-base:::tryCatchOne(expr, names, parentenv, handlers[[1L]])
9. | | \-base:::doTryCatch(return(expr), name, parentenv, handler)
10. | \-tidyselect:::instrument_base_errors(expr)
11. | \-base::withCallingHandlers(...)
12. \-vctrs::vec_as_subscript2(i, arg = "var", logical = "error")
13. \-vctrs:::result_get(...)
Option 3: rapply and lapply
Both code snippets work and preserve the data structure. When I want to convert the data to a matrix for further processing the data structure is messed up. I suspect because the data is still nested one level deep.
#code line returns list nested one level deep
FBraw <- lapply(dataRAW, rapply, f = c)
str(FBraw)
List of 40
$ : Named chr [1:7] "1611853326" "posts/media/ChronikFotos_QNGAWvS8aw/144245114_3813727445333297_3682316138130576479_n_3813727441999964.jpg" "1611853319" "1613542113" ...
..- attr(*, "names")= chr [1:7] "timestamp" "attachments.data.media.uri" "attachments.data.media.creation_timestamp" "attachments.data.media.media_metadata.photo_metadata.exif_data.taken_timestamp" ...
$ : Named chr [1:7] "1611860575" "posts/media/ChronikFotos_QNGAWvS8aw/143276316_3813978641974844_3663341405860849380_n_3813978635308178.png" "1611860403" "1612935033" ...
..- attr(*, "names")= chr [1:7] "timestamp" "attachments.data.media.uri" "attachments.data.media.creation_timestamp" "attachments.data.media.media_metadata.photo_metadata.exif_data.taken_timestamp" ...
$ : Named chr [1:7] "1612948020" "posts/media/ChronikFotos_QNGAWvS8aw/143732770_3813831571989551_5247994518213519901_n_3813831568656218.png" "1611856188" "1617631305" ...
#code snippet 2
FBraw <- lapply(dataRAW, function(x) data.frame(t(rapply(x, function(x) x[1]))))
str(FBraw, head = 1)
List of 40
$ :'data.frame': 1 obs. of 7 variables:
$ :'data.frame': 1 obs. of 7 variables:
$ :'data.frame': 1 obs. of 7 variables:
Sample Data
dataRAW <- list(
list(
timestamp = 1611853326, attachments = list(list(data = list(
list(media = list(
uri = "posts/media/ChronikFotos_QNGAWvS8aw/144245114_3813727445333297_3682316138130576479_n_3813727441999964.jpg",
creation_timestamp = 1611853319, media_metadata = list(
photo_metadata = list(exif_data = list(c(taken_timestamp = 1613542113)))
),
title = "Chronik-Fotos", description = "Da haben wir den Salat! <U+0001F957> \nGemischt oder grün: Verfeinert mit Frieda’s Traum Salatsauce wird der einfachste Salat zum Gaumenschmaus.\n\nProbieren Sie auch unsere Gewürze, Bouillons und verschiedene Käse! \nHier finden Sie alle unsere würzigen Produkte: www.friedas-traum.ch/\n\n<U+0001D46D><U+0001D493><U+0001D48A><U+0001D486><U+0001D485><U+0001D482>'<U+0001D494> <U+0001D47B><U+0001D493><U+0001D482><U+0001D496><U+0001D48E> – Saucen Bouillons Gewürze\nwww.friedas-traum.ch | shop@friedas.ch | Tel. 055 0"
))
))),
data = list(post = 1)
),
list(
timestamp = 1611860575, attachments = list(list(data = list(
list(media = list(
uri = "posts/media/ChronikFotos_QNGAWvS8aw/143276316_3813978641974844_3663341405860849380_n_3813978635308178.png",
creation_timestamp = 1611860403, media_metadata = list(
photo_metadata = list(exif_data = list(c(taken_timestamp = 1612935033)))
),
title = "Chronik-Fotos", description = "Früher über die Gasse – heute im Online- Shop: <U+0001D5D9><U+0001D5FF><U+0001D5F6><U+0001D5F2><U+0001D5F1><U+0001D5EE>’<U+0001D600> <U+0001D5E7><U+0001D5FF><U+0001D5EE><U+0001D602><U+0001D5FA> Produkte. \n\nWas im Restaurant Löwen in Spreitenbach begann, geht heute online weiter: Sie erhalten 100% Geschmack!\n\nEinfach bestellen im Shop: www.friedas-traum.ch/\n\n<U+0001D46D><U+0001D493><U+0001D48A><U+0001D486><U+0001D485><U+0001D482>’<U+0001D494> <U+0001D47B><U+0001D493><U+0001D482><U+0001D496><U+0001D48E> – Saucen, Bouillons, Gewürze\nshop@friedas.ch | Tel. +41 (0) 55 0"
))
))),
data = list(c(post = "Früher über die Gasse – heute im Online- Shop: <U+0001D5D9><U+0001D5FF><U+0001D5F6><U+0001D5F2><U+0001D5F1><U+0001D5EE>’<U+0001D600> <U+0001D5E7><U+0001D5FF><U+0001D5EE><U+0001D602><U+0001D5FA> Produkte. \n\nWas im Restaurant Löwen in Spreitenbach begann, geht heute online weiter: Sie erhalten 100% Geschmack!\n\nEinfach bestellen im Shop: www.friedas-traum.ch/\n\n<U+0001D46D><U+0001D493><U+0001D48A><U+0001D486><U+0001D485><U+0001D482>’<U+0001D494> <U+0001D47B><U+0001D493><U+0001D482><U+0001D496><U+0001D48E> – Saucen, Bouillons, Gewürze\nshop@friedas.ch | Tel. +41 (0) 55 0"))
),
list(
timestamp = 1612948020, attachments = list(list(data = list(
list(media = list(
uri = "posts/media/ChronikFotos_QNGAWvS8aw/143732770_3813831571989551_5247994518213519901_n_3813831568656218.png",
creation_timestamp = 1611856188, media_metadata = list(
photo_metadata = list(exif_data = list(c(taken_timestamp = 1617631305)))
),
title = "Chronik-Fotos", description = "<U+0001D5E1><U+0001D5EE><U+0001D5F0><U+0001D5F5> <U+0001D5EE><U+0001D5F9><U+0001D601><U+0001D5F2><U+0001D5FA> <U+0001D5E5><U+0001D5F2><U+0001D607><U+0001D5F2><U+0001D5FD><U+0001D601> von Hand gemischt und abgefüllt: Frieda’s Salatsaucen sind beliebt wie eh und je. <U+0001F44C>\n\nFrüher der Renner im Restaurant Löwen in Spreitenbach, heute: DER Hit zum Bestellen für Sie zu Hause.\n\nProbieren Sie auch unsere Bouillons, Gewürze und unseren Käse! \n\nHier geht’s zum Shop: www.friedas-traum.ch/\n\n<U+0001D46D><U+0001D493><U+0001D48A><U+0001D486><U+0001D485><U+0001D482>’<U+0001D494> <U+0001D47B><U+0001D493><U+0001D482><U+0001D496><U+0001D48E>® – Saucen Bouillons Gewürze\nshop@friedas.ch | Tel. 055 0"
))
))),
data = list(c(post = "<U+0001D5E1><U+0001D5EE><U+0001D5F0><U+0001D5F5> <U+0001D5EE><U+0001D5F9><U+0001D601><U+0001D5F2><U+0001D5FA> <U+0001D5E5><U+0001D5F2><U+0001D607><U+0001D5F2><U+0001D5FD><U+0001D601> von Hand gemischt und abgefüllt: Frieda’s Salatsaucen sind beliebt wie eh und je. <U+0001F44C>\n\nFrüher der Renner im Restaurant Löwen in Spreitenbach, heute: DER Hit zum Bestellen für Sie zu Hause.\n\nProbieren Sie auch unsere Bouillons, Gewürze und unseren Käse! \n\nHier geht’s zum Shop: www.friedas-traum.ch/\n\n<U+0001D46D><U+0001D493><U+0001D48A><U+0001D486><U+0001D485><U+0001D482>’<U+0001D494> <U+0001D47B><U+0001D493><U+0001D482><U+0001D496><U+0001D48E>® – Saucen Bouillons Gewürze\nshop@friedas.ch | Tel. 055 0"))
)
)
Any ideas and suggestions appreciated. Thanks.
