TSpider Delphi Reference
TSpider
* This is a freeware class/component/library.
Chilkat Spider web crawler component.
Object Creation
var
obj: TSpider;
...
begin
obj := TSpider.Create(Self);
Properties
property AvoidHttps: Integer
If set the 1 (true) the spider will avoid all HTTPS URLs. The default is 0 (false).
property CacheDir: WideString
Specifies a cache directory to use for spidering. If either of the FetchFromCache or UpdateCache properties are true, this is the location of the cache to be used. Note: the Internet Explorer, Netscape, and FireFox caches are completely separate from the Chilkat Spider cache directory. You should specify a new and empty directory.
property ChopAtQuery: Integer
If equal to 1 (true), then the query portion of all URLs are automatically removed when adding to the unspidered list. The default value is 0 (false).
property ConnectTimeout: Integer
The maximum number of seconds to wait while connecting to an HTTP server.
property Domain: WideString readonly
The domain name that is being spidered. This is the domain previously set in the Initialize method.
property FetchFromCache: Integer
If equal to 1 (true) then pages are fetched from cache when possible. If 0, the cache is ignored. The default value is 1. Regardless, if no CacheDir is set then the cache is not used.
property HeartbeatMs: Integer
To be documented soon...
property LastErrorHtml: WideString readonly
Error information in HTML format for the last method called.
property LastErrorText: WideString readonly
Error information in plain-text format for the last method called.
property LastErrorXml: WideString readonly
Error information in XML format for the last method called.
property LastFromCache: Integer readonly
Equal to 1 if the last page spidered was fetched from the cache. Otherwise equal to 0.
property LastHtml: WideString readonly
The HTML text of the last paged fetched by the spider.
property LastHtmlDescription: WideString readonly
The HTML META description from the last page fetched by the spider.
property LastHtmlKeywords: WideString readonly
The HTML META keywords from the last page fetched by the spider.
property LastHtmlTitle: WideString readonly
The HTML title from the last page fetched by the spider.
property LastModDate: TDateTime readonly
The last-modification date of the last URL spidered.
property LastUrl: WideString readonly
The URL of the last page spidered.
property MaxResponseSize: Integer
The maximum HTTP response size allowed. The spider will automatically fail any pages larger than this size. The default value is 250,000 bytes.
property MaxUrlLen: Integer
The maximum URL length allowed. URLs longer than this are not added to the unspidered list. The default value is 200.
property NumAvoidPatterns: Integer readonly
The number of avoid patterns previously set by calling AddAvoidPattern.
property NumFailed: Integer readonly
The number of URLs in the component's failed URL list.
property NumOutboundLinks: Integer readonly
The number of URLs in the component's outbound links URL list.
property NumSpidered: Integer readonly
The number of URLs in the component's already-spidered URL list.
property NumUnspidered: Integer readonly
The number of URLs in the component's unspidered URL list.
property ProxyDomain: WideString
(PreRelease) The domain name of a proxy host if an HTTP proxy is used.
property ProxyLogin: WideString
(PreRelease) If an HTTP proxy is used and it requires authentication, this property specifies the HTTP proxy login.
property ProxyPassword: WideString
(PreRelease) If an HTTP proxy is used and it requires authentication, this property specifies the HTTP proxy password.
property ProxyPort: Integer
(PreRelease) The port number of a proxy server if an HTTP proxy is used.
property ReadTimeout: Integer
The maximum number of seconds to wait when reading from an HTTP server.
property UpdateCache: Integer
If equal to 1 (true) then pages saved to the cache. If 0, the cache is ignored. The default value is 1. Regardless, if no CacheDir is set then the cache is not used.
property UserAgent: WideString
To be documented soon...
property Version: WideString readonly
The version (such as "1.0") of the spider component.
property WindDownCount: Integer
The "wind-down" phase begins when this number of URLs has been spidered. When in the wind-down phase, no new URLs are added to the unspidered list. The default value is 0 which means that there is NO wind-down phase.
Methods
procedure AddAvoidOutboundLinkPattern(pattern: WideString);
Adds a wildcarded pattern to prevent collecting matching outbound link URLs. For example, if "*google*" is added, then any outbound links containing the word "google" will be ignored. The "*" character matches zero or more of any character.
procedure AddAvoidPattern(pattern: WideString);
Adds a wildcarded pattern to prevent spidering matching URLs. For example, if "*register*" is added, then any url containing the word "register" is not spidered. The "*" character matches zero or more of any character.
procedure AddMustMatchPattern(pattern: WideString);
Adds a wildcarded pattern to limit spidering to only URLs that match the pattern. For example, if "*/products/*" is added, then only URLs containing "/products/" are spidered. This is helpful for only spidering a portion of a website. The "*" character matches zero or more of any character.
procedure AddUnspidered(url: WideString);
To begin spidering you must call this method one or more times to provide starting points. It adds a single URL to the component's internal queue of URLs to be spidered.
function CanonicalizeUrl(url: WideString): WideString;
To be documented soon...
procedure ClearFailedUrls();
Clears the component's internal list of URLs that could not be downloaded.
procedure ClearOutboundLinks();
Clears the component's internal list of outbound URLs that will automatically accumulate while spidering.
procedure ClearSpideredUrls();
Clears the component's internal list of already-spidered URLs that will automatically accumulate while spidering.
function CrawlNext(): Integer;
Crawls the next URL in the internal list of unspidered URLs. The URL is moved from the unspidered list to the spidered list. Any new links within the same domain and not yet spidered are added to the unspidered list. (providing that they do not match "avoid" patterns, etc.) Any new outbound links are added to the outbound URL list.
This method returns the HTML of the page downloaded. If there are no more URLs left unspidered, a NULL value is returned. Information about the URL crawled is available in the properties LastUrl, LastFromCache, and LastModDate.
function FetchRobotsText(): WideString;
Returns the contents of the robots.txt file from the domain being crawled. This spider component will not crawl URLs excluded by robots.txt. If you believe the spider is not behaving correctly, please notify us at support@chilkatsoft.com and provide information detailing a case that allows us to reproduce the problem. Returns a null on failure
function GetAvoidPattern(index: Integer): WideString;
Returns the Nth avoid pattern previously added by calling AddAvoidPattern. Indexing begins at 0. Returns a null on failure
function GetBaseDomain(domain: WideString): WideString;
To be documented soon...
function GetDomain(url: WideString): WideString;
To be documented soon...
function GetFailedUrl(index: Integer): WideString;
Returns the Nth URL in the failed URL list. Indexing begins at 0. Returns a null on failure
function GetOutboundLink(index: Integer): WideString;
Returns the Nth URL in the outbound link URL list. Indexing begins at 0. Returns a null on failure
function GetSpideredUrl(index: Integer): WideString;
Returns the Nth URL in the already-spidered URL list. Indexing begins at 0. Returns a null on failure
function GetUnspideredUrl(index: Integer): WideString;
Returns the Nth URL in the unspidered URL list. Indexing begins at 0. Returns a null on failure
procedure Initialize(domain: WideString);
Initializes the component to begin spidering a domain. Calling Initialize clears any patterns added via the AddAvoidOutboundLinkPattern, AddAvoidPattern, and AddMustMatchPattern methods. The domain name passed to this method is what is returned by the Domain property. The spider only crawls URLs within the same domain.
function RecrawlLast(): Integer;
Re-crawls the last URL spidered. This helpful when cookies set in a previous page load cause the page to be loaded differently the next time.
function SaveLastError(filename: WideString): Integer;
Saves the last error information to an XML formatted file.
procedure SkipUnspidered(index: Integer);
Moves a URL from the unspidered list to the spidered list. This allows an application to skip a specific URL.
procedure Sleep(numSeconds: Integer);
To be documented soon...
procedure SleepMs(millisec: Integer);
To be documented soon...
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