How Safe Is It To Scrape Stock-Price Information
As far as I can see, there are no developer-API services for stock-price information with the following stipulations:
- Free or low-monthly cost (
- Ability to ship code which uses the service to multiple parties (e.g. an iPhone app)
- No per-transaction/lookup cost
- No limit on number of lookups or transactions
So I find that I am forced to look at scraping. It seems that the easiest thing to 'scrape' is Yahoo's CSV service which was linked to elsewhere on StackOverflow:
E.g.: http://finance.yahoo.com/d/quotes.csv?s=msft&f=price
That's actually very easy to parse. But I wonder how fragile this is, clearly if Yahoo removes this service, or changes things, or limits the number of lookups severely, then the clients I build could be affected.
How would others approach this problem, or is it simply a case that the data is too valuable and that it's not available at my price? I have searched for a fairly reliable, 20-min delayed service, but simply can't find one that looks as though it will still be around in 6 months.
Any advice much appreciated.
Answer
Did you look at Google's Market Data API?
Update April 2013 - Market Data API no longer available