Lua

Avoid URLs Matching Any of a Set of Patterns

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Demonstrates how to use "avoid patterns" to prevent spidering any URL that matches a wildcarded pattern. This example avoids URLs containing the substrings "java", "python", or "perl". Lua

local chilkat = require("chilkat")

local success = false

local spider = chilkat.Spider.new()

-- The spider object crawls a single web site at a time.  As you'll see
-- in later examples, you can collect outbound links and use them to
-- crawl the web.  For now, we'll simply spider 10 pages of chilkatsoft.com
spider:initialize("www.chilkatsoft.com")

-- Add the 1st URL:
spider:add_unspidered("http://www.chilkatsoft.com/")

-- Avoid URLs matching these patterns:
spider:add_avoid_pattern("*java*")
spider:add_avoid_pattern("*python*")
spider:add_avoid_pattern("*perl*")

-- Begin crawling the site by calling CrawlNext repeatedly.
for i = 0, 9 do
    success = spider:crawl_next()
    if success then
        -- Show the URL of the page just spidered.
        print(spider.last_url)
        -- The HTML is available in the LastHtml property
    else
        -- Did we get an error or are there no more URLs to crawl?
        if spider.num_unspidered == 0 then
            print("No more URLs to spider")
        else
            print(spider.last_error_text)
        end
    end

    -- Sleep 1 second before spidering the next URL.
    spider:sleep_ms(1000)
end