get-yahoo-quotes.sh

#!/bin/bash
##
## Script to download Yahoo historical quotes using the new cookie authenticated site.
##
## Usage: get-yahoo-quotes SYMBOL
##
##
## Author: Brad Lucas brad@beaconhill.com
## Latest: https://github.com/bradlucas/get-yahoo-quotes
##
## Copyright (c) 2017 Brad Lucas - All Rights Reserved
##
##
## History
##
## 06-03-2017 : Created script
##
## ----------------------------------------------------------------------------------------------------

SYMBOL=$1
if [[ -z $SYMBOL ]]; then
  echo "Please enter a SYMBOL as the first parameter to this script"
  exit
fi
# echo "Downloading quotes for $SYMBOL"

function log () {
  # To remove logging comment echo statement and uncomment the :
  # To enable logging comment :    statement and uncomment the echo statement
  # echo $1
  :
}

# Period values are 'Seconds since 1970-01-01 00:00:00 UTC'. Also known as Unix time or epoch time.
# Let's just assume we want it all and ask for a date range that starts at 1/1/1970.
# NOTE: This doesn't work for old synbols like IBM which has Yahoo has back to 1962
# START_DATE=0
# END_DATE=$(date +%s)

YEAR_SECS=31622400 #seconds in a year
END_DATE=$(date +%s)
START_DATE=`expr $END_DATE - $YEAR_SECS`

# Store the cookie in a temp file
cookieJar=$(mktemp)

# Get the crumb value
function getCrumb () {
  # Sometimes the value has an octal character
  # echo will convert it
  # https://stackoverflow.com/a/28328480

  # curl the url then replace the } characters with line feeds. This takes the large json one line and turns it into about 3000 lines
  # grep for the CrumbStore line
  # then copy out the value
  # lastly, remove any quotes
  echo -en "$(curl -s --cookie-jar $cookieJar $1)" | tr "}" "\n" | grep CrumbStore | cut -d':' -f 3 | sed 's+"++g'
}

# TODO If crumb is blank then we probably don't have a valid symbol
URL="https://finance.yahoo.com/quote/$SYMBOL/?p=$SYMBOL"
log $URL
crumb=$(getCrumb $URL)
log $crumb
log "CRUMB: $crumb"
if [[ -z $crumb ]]; then
  echo "Error finding a valid crumb value"
  exit
fi


# Build url with SYMBOL, START_DATE, END_DATE
BASE_URL="https://query1.finance.yahoo.com/v7/finance/download/$SYMBOL?period1=$START_DATE&period2=$END_DATE&interval=1d&events=history"
log $BASE_URL

# Add the crumb value
URL="$BASE_URL&crumb=$crumb"
log "URL: $URL"

# Download to 
curl -s --cookie $cookieJar  $URL # >$SYMBOL.csv

# echo "Data dowmloaded to $SYMBOL.csv"