Unicode C

A Simple Web Crawler

See more Spider Examples

This demonstrates a very simple web crawler using the Chilkat Spider component. Unicode C

#include <C_CkSpiderW.h>
#include <C_CkStringArrayW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSpiderW spider;
    HCkStringArrayW seenDomains;
    HCkStringArrayW seedUrls;
    const wchar_t *url;
    const wchar_t *domain;
    int i;
    const wchar_t *domain;
    const wchar_t *baseDomain;

    success = FALSE;

    spider = CkSpiderW_Create();

    seenDomains = CkStringArrayW_Create();
    seedUrls = CkStringArrayW_Create();

    CkStringArrayW_putUnique(seenDomains,TRUE);
    CkStringArrayW_putUnique(seedUrls,TRUE);

    // You will need to change the start URL to something else...
    CkStringArrayW_Append(seedUrls,L"http://something.whateverYouWant.com/");

    // Set outbound URL exclude patterns
    // URLs matching any of these patterns will not be added to the 
    // collection of outbound links.
    CkSpiderW_AddAvoidOutboundLinkPattern(spider,L"*?id=*");
    CkSpiderW_AddAvoidOutboundLinkPattern(spider,L"*.mypages.*");
    CkSpiderW_AddAvoidOutboundLinkPattern(spider,L"*.personal.*");
    CkSpiderW_AddAvoidOutboundLinkPattern(spider,L"*.comcast.*");
    CkSpiderW_AddAvoidOutboundLinkPattern(spider,L"*.aol.*");
    CkSpiderW_AddAvoidOutboundLinkPattern(spider,L"*~*");

    // Use a cache so we don't have to re-fetch URLs previously fetched.
    CkSpiderW_putCacheDir(spider,L"c:/spiderCache/");
    CkSpiderW_putFetchFromCache(spider,TRUE);
    CkSpiderW_putUpdateCache(spider,TRUE);

    while (CkStringArrayW_getCount(seedUrls) > 0) {

        url = CkStringArrayW_pop(seedUrls);
        CkSpiderW_Initialize(spider,url);

        // Spider 5 URLs of this domain.
        // but first, save the base domain in seenDomains
        domain = CkSpiderW_getUrlDomain(spider,url);
        CkStringArrayW_Append(seenDomains,CkSpiderW_getBaseDomain(spider,domain));

        for (i = 0; i <= 4; i++) {
            success = CkSpiderW_CrawlNext(spider);
            if (success == TRUE) {

                // Display the URL we just crawled.
                wprintf(L"%s\n",CkSpiderW_lastUrl(spider));

                // If the last URL was retrieved from cache,
                // we won't wait.  Otherwise we'll wait 1 second
                // before fetching the next URL.
                if (CkSpiderW_getLastFromCache(spider) != TRUE) {
                    CkSpiderW_SleepMs(spider,1000);
                }

            }
            else {
                // cause the loop to exit..
                i = 999;
            }

        }

        // Add the outbound links to seedUrls, except
        // for the domains we've already seen.
        for (i = 0; i <= CkSpiderW_getNumOutboundLinks(spider) - 1; i++) {

            url = CkSpiderW_getOutboundLink(spider,i);
            domain = CkSpiderW_getUrlDomain(spider,url);
            baseDomain = CkSpiderW_getBaseDomain(spider,domain);
            if (CkStringArrayW_Contains(seenDomains,baseDomain) == FALSE) {
                // Don't let our list of seedUrls grow too large.
                if (CkStringArrayW_getCount(seedUrls) < 1000) {
                    CkStringArrayW_Append(seedUrls,url);
                }

            }

        }

    }



    CkSpiderW_Dispose(spider);
    CkStringArrayW_Dispose(seenDomains);
    CkStringArrayW_Dispose(seedUrls);

    }