library-mirrors/ftcsv
1
0
Fork 0
mirror of https://github.com/FourierTransformer/ftcsv.git synced 2024-11-19 19:54:23 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

added more unit tests and finalized api

Browse Source
This commit is contained in:
FourierTransformer 2016-03-13 00:33:31 -06:00
parent 66e8c1306e
commit d24a00c290
5 changed files with 273 additions and 72 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

185
ftcsv.lua
View File

@ -1,5 +1,28 @@
---------------
-- ## ftcsv, a fairly fast csv library written in pure lua
--
-- It works well for CSVs that can easily be fully loaded into memory (easily
-- up to a hundred MBs). Currently, there isn't a "large" file mode with
-- proper readers and writers for ingesting CSVs in bulk with a fixed amount
-- of memory
--
-- @author Shakil Thakur
-- @copyright 2016
-- @license MIT
---------------
local ftcsv = {}
-- load an entire file into memory
local function loadFile(textFile)
local file = io.open(textFile, "r")
if not file then error("File not found at " .. textFile) end
local allLines = file:read("*all")
file:close()
return allLines
end
-- finds the end of an escape sequence
local function findClosingQuote(i, inputLength, inputString, quote, doubleQuoteEscape)
local doubleQuoteEscape = doubleQuoteEscape
while i <= inputLength do
@ -20,19 +43,23 @@ local function findClosingQuote(i, inputLength, inputString, quote, doubleQuoteE
end
end
-- creates a new field and adds it to the main table
local function createNewField(inputString, quote, fieldStart, i, line, fieldNum, doubleQuoteEscape, fieldsToKeep)
-- print(lineNum, fieldNum, fieldStart, i-1)
-- so, if we just recently de-escaped, we don't want the trailing \"
-- if fieldsToKeep == nil then
-- local fieldsToKeep = fieldsToKeep
local output = line[fieldNum]
if fieldsToKeep == nil or fieldsToKeep[fieldNum] then
-- print(fieldsToKeep)
-- print("b4", i, fieldNum, line[fieldNum])
if string.byte(inputString, i-1) == quote then
-- print("Skipping last \"")
line[fieldNum] = string.sub(inputString, fieldStart, i-2)
else
line[fieldNum] = string.sub(inputString, fieldStart, i-1)
end
-- print("aft", i, fieldNum, line[fieldNum])
-- remove the double quotes (if they existed)
if doubleQuoteEscape then
-- print("QUOTE REPLACE")
@ -43,11 +70,13 @@ local function createNewField(inputString, quote, fieldStart, i, line, fieldNum,
end
end
-- creates the headers after reading through to the first line
local function createHeaders(line, rename, fieldsToKeep)
-- print("CREATING HEADERS")
local headers = {}
for i = 1, #line do
if rename[line[i]] then
-- print("RENAMING", line[i], rename[line[i]])
headers[i] = rename[line[i]]
else
headers[i] = line[i]
@ -61,39 +90,46 @@ local function createHeaders(line, rename, fieldsToKeep)
return headers, 0, true, fieldsToKeep
end
function ftcsv.decode(inputString, separator, options)
-- main function used to parse
function ftcsv.parse(inputFile, delimiter, options)
-- each line in outResults holds another table
local outResults = {}
outResults[1] = {}
-- separator MUST be one character
if #separator ~= 1 and type("separator") ~= "string" then error("the separator must be of string type and exactly one character") end
local separator = string.byte(separator)
-- delimiter MUST be one character
assert(#delimiter == 1 and type(delimiter) == "string", "the delimiter must be of string type and exactly one character")
local delimiter = string.byte(delimiter)
-- OPTIONS yo
local header = true
local rename = {}
local fieldsToKeep = nil
local ofieldsToKeep = nil
local loadFromString = false
if options then
if options.headers ~= nil then
if type(options.headers) ~= "boolean" then
error("ftcsv only takes the boolean 'true' or 'false' for the optional parameter 'headers' (default 'true'). You passed in '" .. options.headers .. "' of type '" .. type(options.headers) .. "'.")
end
assert(type(options.headers) == "boolean", "ftcsv only takes the boolean 'true' or 'false' for the optional parameter 'headers' (default 'true'). You passed in '" .. tostring(options.headers) .. "' of type '" .. type(options.headers) .. "'.")
header = options.headers
end
if options.rename ~= nil then
if type(options.rename) ~= "table" then
error("ftcsv only takes in a key-value table for the optional parameter 'rename'. You passed in '" .. options.rename .. "' of type '" .. type(options.rename) .. "'.")
end
assert(type(options.rename) == "table", "ftcsv only takes in a key-value table for the optional parameter 'rename'. You passed in '" .. tostring(options.rename) .. "' of type '" .. type(options.rename) .. "'.")
rename = options.rename
end
if options.fieldsToKeep ~= nil then
assert(type(options.fieldsToKeep) == "table", "ftcsv only takes in a list (as a table) for the optional parameter 'fieldsToKeep'. You passed in '" .. tostring(options.fieldsToKeep) .. "' of type '" .. type(options.fieldsToKeep) .. "'.")
ofieldsToKeep = options.fieldsToKeep
if type(options.fieldsToKeep) ~= "table" then
error("ftcsv only takes in a list (as a table for the optional parameter 'fieldsToKeep'. You passed in '" .. options.fieldsToKeep .. "' of type '" .. type(options.fieldsToKeep) .. "'.")
end
if options.loadFromString ~= nil then
assert(type(options.loadFromString) == "boolean", "ftcsv only takes a boolean value for optional parameter 'loadFromString'. You passed in '" .. tostring(options.loadFromString) .. "' of type '" .. type(options.loadFromString) .. "'.")
loadFromString = options.loadFromString
end
end
local inputString
if loadFromString then
inputString = inputFile
else
inputString = loadFile(inputFile)
end
local CR = string.byte("\r")
@ -138,7 +174,7 @@ function ftcsv.decode(inputString, separator, options)
-- end
-- create some fields if we can!
elseif currentChar == separator then
elseif currentChar == delimiter then
-- for that first field
if not headerSet and lineNum == 1 then
headerField[fieldNum] = fieldNum
@ -196,40 +232,65 @@ function ftcsv.decode(inputString, separator, options)
-- clean up last line if it's weird (this happens when there is a CRLF newline at end of file)
-- doing a count gets it to pick up the oddballs
local count = 0
for _, _ in pairs(outResults[lineNum]) do
count = count + 1
local finalLineCount = 0
for _, value in pairs(outResults[lineNum]) do
finalLineCount = finalLineCount + 1
end
if count ~= #headerField then
local initialLineCount = 0
for _, value in pairs(outResults[1]) do
initialLineCount = initialLineCount + 1
end
-- print("Final/Initial", finalLineCount, initialLineCount)
if finalLineCount ~= initialLineCount then
outResults[lineNum] = nil
end
return outResults
end
-- a function that delimits " to "", used by the writer
local function delimitField(field)
if field:find('"') then
return '"' .. field:gsub('"', '""') .. '"'
elseif field:find(" ") or field:find(",") or field:find("\n") then
return '"' .. field .. '"'
elseif field == "" then
return '""'
return field:gsub('"', '""')
else
return field
end
end
function ftcsv.encode(inputTable, separator, headers)
-- separator MUST be one character
if #separator ~= 1 and type("separator") ~= "string" then error("the separator must be of string type and exactly one character") end
-- keep track of me output
local output = {}
-- grab the headers from the first file if they are not provided
-- we'll do this easily and not so quickly...
-- a function that compiles some lua code to quickly print out the csv
local function writer(inputTable, dilimeter, headers)
-- they get re-created here if they need to be escaped so lua understands it based on how
-- they came in
local headers = headers
if headers == nil then
for i = 1, #headers do
if inputTable[1][headers[i]] == nil then
error("the field '" .. headers[i] .. "' doesn't exist in the table")
end
if headers[i]:find('"') then
headers[i] = headers[i]:gsub('"', '\\"')
end
end
local outputFunc = [[
local state, i = ...
local d = state.delimitField
i = i + 1;
if i > state.tableSize then return nil end;
return i, '"' .. d(state.t[i]["]] .. table.concat(headers, [["]) .. '"]] .. dilimeter .. [["' .. d(state.t[i]["]]) .. [["]) .. '"\r\n']]
-- print(outputFunc)
local state = {}
state.t = inputTable
state.tableSize = #inputTable
state.delimitField = delimitField
return load(outputFunc), state, 0
end
-- takes the values from the headers in the first row of the input table
local function extractHeaders(inputTable)
headers = {}
for key, _ in pairs(inputTable[1]) do
headers[#headers+1] = key
@ -237,34 +298,48 @@ function ftcsv.encode(inputTable, separator, headers)
-- lets make the headers alphabetical
table.sort(headers)
return headers
end
-- turns a lua table into a csv
-- works really quickly with luajit-2.1, because table.concat life
function ftcsv.encode(inputTable, delimiter, options)
local output = {}
-- dilimeter MUST be one character
assert(#delimiter == 1 and type(delimiter) == "string", "the delimiter must be of string type and exactly one character")
local delimiter = delimiter
-- grab the headers from the options if they are there
local headers = nil
if options then
if options.headers ~= nil then
assert(type(options.headers) == "table", "ftcsv only takes in a list (as a table) for the optional parameter 'headers'. You passed in '" .. tostring(options.headers) .. "' of type '" .. type(options.headers) .. "'.")
headers = options.headers
end
end
if headers == nil then
headers = extractHeaders(inputTable)
end
-- this is for outputting the headers
local line = {}
for i, header in ipairs(headers) do
line[i] = delimitField(header)
-- newHeaders are needed if there are quotes within the header
-- because they need to be escaped
local newHeaders = {}
for i = 1, #headers do
if headers[i]:find('"') then
newHeaders[i] = headers[i]:gsub('"', '""')
else
newHeaders[i] = headers[i]
end
line.length = #line
end
output[1] = '"' .. table.concat(newHeaders, '","') .. '"\r\n'
-- string the header together yo
output[1] = table.concat(line, separator)
-- cheap and fast (because buffers)
for i, fields in ipairs(inputTable) do
local numHeaders = 0
for j = 1, #headers do
local field = fields[headers[j]]
line[j] = delimitField(field)
numHeaders = j
-- add each line by line.
for i, line in writer(inputTable, delimiter, headers) do
output[i+1] = line
end
-- all lines should have the same number of fields
if line.length ~= numHeaders then
error("All lines should have the same length. The line at row " .. i .. " is of length " .. numHeaders .. " instead of " .. line.length)
end
output[i+1] = table.concat(line, separator)
end
return table.concat(output, "\r\n")
return table.concat(output)
end
return ftcsv

3
spec/csvs/escaped_quotes_in_header.csv Normal file
View File

@ -0,0 +1,3 @@
"li""on",tiger,"be""ar"
1,2,3
5,6,7
1 li"on tiger be"ar
2 1 2 3
3 5 6 7

109
spec/feature_spec.lua Normal file
View File

@ -0,0 +1,109 @@
local ftcsv = require('ftcsv')
describe("csv features", function()
it("should handle loading from string", function()
local expected = {}
expected[1] = {}
expected[1].a = "apple"
expected[1].b = "banana"
expected[1].c = "carrot"
local actual = ftcsv.parse("a,b,c\napple,banana,carrot", ",", {loadFromString=true})
assert.are.same(expected, actual)
end)
it("should handle crlf loading from string", function()
local expected = {}
expected[1] = {}
expected[1].a = "apple"
expected[1].b = "banana"
expected[1].c = "carrot"
local actual = ftcsv.parse("a,b,c\r\napple,banana,carrot", ",", {loadFromString=true})
assert.are.same(expected, actual)
end)
it("should handle renaming a field", function()
local expected = {}
expected[1] = {}
expected[1].d = "apple"
expected[1].b = "banana"
expected[1].c = "carrot"
local actual = ftcsv.parse("a,b,c\r\napple,banana,carrot", ",", {loadFromString=true, rename={["a"] = "d"}})
assert.are.same(expected, actual)
end)
it("should handle renaming multiple fields", function()
local expected = {}
expected[1] = {}
expected[1].d = "apple"
expected[1].e = "banana"
expected[1].f = "carrot"
local options = {loadFromString=true, rename={["a"] = "d", ["b"] = "e", ["c"] = "f"}}
local actual = ftcsv.parse("a,b,c\r\napple,banana,carrot", ",", options)
assert.are.same(expected, actual)
end)
it("should handle renaming multiple fields to the same out value", function()
local expected = {}
expected[1] = {}
expected[1].d = "apple"
expected[1].e = "carrot"
local options = {loadFromString=true, rename={["a"] = "d", ["b"] = "e", ["c"] = "e"}}
local actual = ftcsv.parse("a,b,c\r\napple,banana,carrot", ",", options)
assert.are.same(expected, actual)
end)
it("should handle renaming multiple fields to the same out value with newline at end", function()
local expected = {}
expected[1] = {}
expected[1].d = "apple"
expected[1].e = "carrot"
local options = {loadFromString=true, rename={["a"] = "d", ["b"] = "e", ["c"] = "e"}}
local actual = ftcsv.parse("a,b,c\r\napple,banana,carrot\r\n", ",", options)
assert.are.same(expected, actual)
end)
it("should handle only keeping a few fields", function()
local expected = {}
expected[1] = {}
expected[1].a = "apple"
expected[1].b = "banana"
local options = {loadFromString=true, fieldsToKeep={"a","b"}}
local actual = ftcsv.parse("a,b,c\r\napple,banana,carrot\r\n", ",", options)
assert.are.same(expected, actual)
end)
it("should handle only keeping a few fields with a rename to an existing field", function()
local expected = {}
expected[1] = {}
expected[1].a = "apple"
expected[1].b = "carrot"
local options = {loadFromString=true, fieldsToKeep={"a","b"}, rename={["c"] = "b"}}
local actual = ftcsv.parse("a,b,c\r\napple,banana,carrot\r\n", ",", options)
assert.are.same(expected, actual)
end)
it("should handle only keeping a few fields with a rename to a new field", function()
local expected = {}
expected[1] = {}
expected[1].a = "apple"
expected[1].f = "carrot"
local options = {loadFromString=true, fieldsToKeep={"a","f"}, rename={["c"] = "f"}}
local actual = ftcsv.parse("a,b,c\r\napple,banana,carrot\r\n", ",", options)
assert.are.same(expected, actual)
end)
it("should handle files without headers", function()
local expected = {}
expected[1] = {}
expected[1][1] = "apple"
expected[1][2] = "banana"
expected[1][3] = "carrot"
expected[2] = {}
expected[2][1] = "diamond"
expected[2][2] = "emerald"
expected[2][3] = "pearl"
local options = {loadFromString=true, header=false}
local actual = ftcsv.parse("apple>banana>carrot\ndiamond>emerald>pearl", ">", options)
end)
end)

12
spec/json/escaped_quotes_in_header.json Normal file
View File

@ -0,0 +1,12 @@
[
{
"li\"on": "1",
"tiger": "2",
"be\"ar": "3"
},
{
"li\"on": "5",
"tiger": "6",
"be\"ar": "7"
}
]

26
spec/test_spec.lua → spec/parse_encode_spec.lua
View File

@ -1,7 +1,5 @@
local cjson = require("cjson")
local ftcsv = require('ftcsv')
-- local csv = require('csv')
-- local staecsv = require('state-csv')
local function loadFile(textFile)
local file = io.open(textFile, "r")
@ -19,6 +17,7 @@ local files = {
"empty_no_quotes",
"empty_crlf",
"escaped_quotes",
"escaped_quotes_in_header",
"json",
"json_no_newline",
"newlines",
@ -32,30 +31,33 @@ local files = {
describe("csv decode", function()
for _, value in ipairs(files) do
it("should handle " .. value, function()
local contents = loadFile("spec/csvs/" .. value .. ".csv")
local json = loadFile("spec/json/" .. value .. ".json")
json = cjson.decode(json)
-- local parse = staecsv:ftcsv(contents, ",")
local parse = ftcsv.decode(contents, ",")
-- local f = csv.openstring(contents, {separator=",", header=true})
-- local parse = {}
-- for fields in f:lines() do
-- parse[#parse+1] = fields
-- end
local parse = ftcsv.parse("spec/csvs/" .. value .. ".csv", ",")
assert.are.same(json, parse)
end)
end
end)
describe("csv decode from string", function()
for _, value in ipairs(files) do
it("should handle " .. value, function()
local contents = loadFile("spec/csvs/" .. value .. ".csv")
local json = loadFile("spec/json/" .. value .. ".json")
json = cjson.decode(json)
local parse = ftcsv.parse(contents, ",", {loadFromString=true})
assert.are.same(json, parse)
end)
end
end)
describe("csv encode", function()
for _, value in ipairs(files) do
it("should handle " .. value, function()
local originalFile = loadFile("spec/csvs/" .. value .. ".csv")
local jsonFile = loadFile("spec/json/" .. value .. ".json")
local jsonDecode = cjson.decode(jsonFile)
-- local parse = staecsv:ftcsv(contents, ",")
local reEncoded = ftcsv.decode(ftcsv.encode(jsonDecode, ","), ",")
local reEncoded = ftcsv.parse(ftcsv.encode(jsonDecode, ","), ",", {loadFromString=true})
-- local f = csv.openstring(contents, {separator=",", header=true})
-- local parse = {}
-- for fields in f:lines() do