Spider Delphi DLL Reference Documentation
Spider
Current Version: 10.0.0
Chilkat Spider web crawler object.
Create/Dispose
var myObject: HCkSpider; begin myObject := CkSpider_Create(); // ... CkSpider_Dispose(myObject); end;
Creates an instance of the HCkSpider object and returns a handle (i.e. a Pointer). The handle is passed in the 1st argument for the functions listed on this page.
Objects created by calling CkSpider_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function.
Properties
AbortCurrent
procedure CkSpider_putAbortCurrent(objHandle: HCkSpider; newPropVal: wordbool); stdcall;
When set to True, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to False when the next method is called. When the abort occurs, this property is reset to False. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)
topAvoidHttps
procedure CkSpider_putAvoidHttps(objHandle: HCkSpider; newPropVal: wordbool); stdcall;
If set the 1 (true) the spider will avoid all HTTPS URLs. The default is 0 (false).
topCacheDir
procedure CkSpider_putCacheDir(objHandle: HCkSpider; newPropVal: PWideChar); stdcall;
function CkSpider__cacheDir(objHandle: HCkSpider): PWideChar; stdcall;
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.
See the notes about PWideChar memory ownership and validity.
ChopAtQuery
procedure CkSpider_putChopAtQuery(objHandle: HCkSpider; newPropVal: wordbool); stdcall;
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).
topConnectTimeout
procedure CkSpider_putConnectTimeout(objHandle: HCkSpider; newPropVal: Integer); stdcall;
The maximum number of seconds to wait while connecting to an HTTP server.
topDebugLogFilePath
procedure CkSpider_putDebugLogFilePath(objHandle: HCkSpider; newPropVal: PWideChar); stdcall;
function CkSpider__debugLogFilePath(objHandle: HCkSpider): PWideChar; stdcall;
If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.
This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:
- a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
- the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
- there is an internal problem (bug) in the Chilkat code that causes the hang.
See the notes about PWideChar memory ownership and validity.
Domain
function CkSpider__domain(objHandle: HCkSpider): PWideChar; stdcall;
The domain name that is being spidered. This is the domain previously set in the Initialize method.
See the notes about PWideChar memory ownership and validity.
topFetchFromCache
procedure CkSpider_putFetchFromCache(objHandle: HCkSpider; newPropVal: wordbool); stdcall;
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.
FinalRedirectUrl
function CkSpider__finalRedirectUrl(objHandle: HCkSpider): PWideChar; stdcall;
If the last URL crawled was redirected (as indicated by the WasRedirected property), this property will contain the final redirect URL.
See the notes about PWideChar memory ownership and validity.
topHeartbeatMs
procedure CkSpider_putHeartbeatMs(objHandle: HCkSpider; newPropVal: Integer); stdcall;
The number of milliseconds between each AbortCheck event callback. The AbortCheck callback allows an application to abort any method call prior to completion. If HeartbeatMs is 0 (the default), no AbortCheck event callbacks will fire.
topLastErrorHtml
function CkSpider__lastErrorHtml(objHandle: HCkSpider): PWideChar; stdcall;
Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.
See the notes about PWideChar memory ownership and validity.
topLastErrorText
function CkSpider__lastErrorText(objHandle: HCkSpider): PWideChar; stdcall;
Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.
See the notes about PWideChar memory ownership and validity.
LastErrorXml
function CkSpider__lastErrorXml(objHandle: HCkSpider): PWideChar; stdcall;
Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.
See the notes about PWideChar memory ownership and validity.
topLastFromCache
Equal to 1 if the last page spidered was fetched from the cache. Otherwise equal to 0.
topLastHtml
function CkSpider__lastHtml(objHandle: HCkSpider): PWideChar; stdcall;
The HTML text of the last paged fetched by the spider.
See the notes about PWideChar memory ownership and validity.
topLastHtmlDescription
function CkSpider__lastHtmlDescription(objHandle: HCkSpider): PWideChar; stdcall;
The HTML META description from the last page fetched by the spider.
See the notes about PWideChar memory ownership and validity.
LastHtmlKeywords
function CkSpider__lastHtmlKeywords(objHandle: HCkSpider): PWideChar; stdcall;
The HTML META keywords from the last page fetched by the spider.
See the notes about PWideChar memory ownership and validity.
LastHtmlTitle
function CkSpider__lastHtmlTitle(objHandle: HCkSpider): PWideChar; stdcall;
The HTML title from the last page fetched by the spider.
See the notes about PWideChar memory ownership and validity.
LastMethodSuccess
procedure CkSpider_putLastMethodSuccess(objHandle: HCkSpider; newPropVal: wordbool); stdcall;
Indicate whether the last method call succeeded or failed. A value of True indicates success, a value of False indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:
- Any method that returns a string.
- Any method returning a Chilkat object, binary bytes, or a date/time.
- Any method returning a standard boolean status value where success = True and failure = False.
- Any method returning an integer where failure is defined by a return value less than zero.
Note: Methods that do not fit the above requirements will always set this property equal to True. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.
topLastModDateStr
function CkSpider__lastModDateStr(objHandle: HCkSpider): PWideChar; stdcall;
The last modification date/time from the last page fetched by the spider.
See the notes about PWideChar memory ownership and validity.
topLastUrl
function CkSpider__lastUrl(objHandle: HCkSpider): PWideChar; stdcall;
MaxResponseSize
procedure CkSpider_putMaxResponseSize(objHandle: HCkSpider; newPropVal: Integer); stdcall;
The maximum HTTP response size allowed. The spider will automatically fail any pages larger than this size. The default value is 250,000 bytes.
MaxUrlLen
procedure CkSpider_putMaxUrlLen(objHandle: HCkSpider; newPropVal: Integer); stdcall;
The maximum URL length allowed. URLs longer than this are not added to the unspidered list. The default value is 200.
NumAvoidPatterns
The number of avoid patterns previously set by calling AddAvoidPattern.
topNumFailed
The number of URLs in the object's failed URL list.
topNumOutboundLinks
The number of URLs in the object's outbound links URL list.
topNumSpidered
The number of URLs in the object's already-spidered URL list.
topNumUnspidered
PreferIpv6
procedure CkSpider_putPreferIpv6(objHandle: HCkSpider; newPropVal: wordbool); stdcall;
If True, then use IPv6 over IPv4 when both are supported for a particular domain. The default value of this property is False, which will choose IPv4 over IPv6.
topProxyDomain
procedure CkSpider_putProxyDomain(objHandle: HCkSpider; newPropVal: PWideChar); stdcall;
function CkSpider__proxyDomain(objHandle: HCkSpider): PWideChar; stdcall;
The domain name of a proxy host if an HTTP proxy is used.
See the notes about PWideChar memory ownership and validity.
topProxyLogin
procedure CkSpider_putProxyLogin(objHandle: HCkSpider; newPropVal: PWideChar); stdcall;
function CkSpider__proxyLogin(objHandle: HCkSpider): PWideChar; stdcall;
If an HTTP proxy is used and it requires authentication, this property specifies the HTTP proxy login.
See the notes about PWideChar memory ownership and validity.
topProxyPassword
procedure CkSpider_putProxyPassword(objHandle: HCkSpider; newPropVal: PWideChar); stdcall;
function CkSpider__proxyPassword(objHandle: HCkSpider): PWideChar; stdcall;
If an HTTP proxy is used and it requires authentication, this property specifies the HTTP proxy password.
See the notes about PWideChar memory ownership and validity.
topProxyPort
procedure CkSpider_putProxyPort(objHandle: HCkSpider; newPropVal: Integer); stdcall;
The port number of a proxy server if an HTTP proxy is used.
topReadTimeout
procedure CkSpider_putReadTimeout(objHandle: HCkSpider; newPropVal: Integer); stdcall;
The maximum number of seconds to wait when reading from an HTTP server.
topUpdateCache
procedure CkSpider_putUpdateCache(objHandle: HCkSpider; newPropVal: wordbool); stdcall;
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.
UserAgent
procedure CkSpider_putUserAgent(objHandle: HCkSpider; newPropVal: PWideChar); stdcall;
function CkSpider__userAgent(objHandle: HCkSpider): PWideChar; stdcall;
The value of the HTTP user-agent header field to be sent with HTTP requests. This can be set to any desired value, but be aware that some websites may reject requests from unknown user agents.
See the notes about PWideChar memory ownership and validity.
topVerboseLogging
procedure CkSpider_putVerboseLogging(objHandle: HCkSpider; newPropVal: wordbool); stdcall;
If set to True, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is False. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
topVersion
function CkSpider__version(objHandle: HCkSpider): PWideChar; stdcall;
Version of the component/library, such as "9.5.0.94"
See the notes about PWideChar memory ownership and validity.
WasRedirected
Indicates whether the last URL crawled was redirected. (True = yes, False = no)
topWindDownCount
procedure CkSpider_putWindDownCount(objHandle: HCkSpider; newPropVal: Integer); stdcall;
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.
topMethods
AddAvoidOutboundLinkPattern
pattern: PWideChar) stdcall;
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.
AddAvoidPattern
pattern: PWideChar) stdcall;
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.
AddMustMatchPattern
pattern: PWideChar) stdcall;
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.
AddUnspidered
url: PWideChar) stdcall;
To begin spidering you must call this method one or more times to provide starting points. It adds a single URL to the object's internal queue of URLs to be spidered.
CanonicalizeUrl
url: PWideChar;
outStr: HCkString): wordbool; stdcall;
function CkSpider__canonicalizeUrl(objHandle: HCkSpider;
url: PWideChar): PWideChar; stdcall;
Canonicalizes a URL by doing the following:
- Drops username/password if present.
- Drops fragment if present.
- Converts domain to lowercase.
- Removes port 80 or 443
- Remove default.asp, index.html, index.htm, default.html, index.htm, default.htm, index.php, index.asp, default.php, .cfm, .aspx, ,php3, .pl, .cgi, .txt, .shtml, .phtml
- Remove www. from the domain if present.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
ClearFailedUrls
Clears the object's internal list of URLs that could not be downloaded.
topClearOutboundLinks
Clears the object's internal list of outbound URLs that will automatically accumulate while spidering.
topClearSpideredUrls
Clears the object's internal list of already-spidered URLs that will automatically accumulate while spidering.
topCrawlNext
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. If successful, the HTML of the downloaded page is available in the LastHtml property. If there are no more URLs left unspidered, the method returns False. Information about the URL crawled is available in the properties LastUrl, LastFromCache, and LastModDate.
CrawlNextAsync (1)
Creates an asynchronous task to call the CrawlNext method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
topFetchRobotsText
outStr: HCkString): wordbool; stdcall;
function CkSpider__fetchRobotsText(objHandle: HCkSpider): PWideChar; stdcall;
Returns the contents of the robots.txt file from the domain being crawled. This spider object will not crawl URLs excluded by robots.txt. If you believe the spider is not behaving correctly, please notify us at [email protected] and provide information detailing a case that allows us to reproduce the problem.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
FetchRobotsTextAsync (1)
Creates an asynchronous task to call the FetchRobotsText method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
topGetAvoidPattern
index: Integer;
outStr: HCkString): wordbool; stdcall;
function CkSpider__getAvoidPattern(objHandle: HCkSpider;
index: Integer): PWideChar; stdcall;
Returns the Nth avoid pattern previously added by calling AddAvoidPattern. Indexing begins at 0.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topGetBaseDomain
domain: PWideChar;
outStr: HCkString): wordbool; stdcall;
function CkSpider__getBaseDomain(objHandle: HCkSpider;
domain: PWideChar): PWideChar; stdcall;
Returns the second-level + top-level domain of the domain. For example, if domain is "xyz.example.com", this returns "example.com". For some domains, such as "xyz.example.co.uk", the top 3 levels are returned, such as "example.co.uk".
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
GetFailedUrl
index: Integer;
outStr: HCkString): wordbool; stdcall;
function CkSpider__getFailedUrl(objHandle: HCkSpider;
index: Integer): PWideChar; stdcall;
Returns the Nth URL in the failed URL list. Indexing begins at 0.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topGetOutboundLink
index: Integer;
outStr: HCkString): wordbool; stdcall;
function CkSpider__getOutboundLink(objHandle: HCkSpider;
index: Integer): PWideChar; stdcall;
Returns the Nth URL in the outbound link URL list. Indexing begins at 0.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topGetSpideredUrl
index: Integer;
outStr: HCkString): wordbool; stdcall;
function CkSpider__getSpideredUrl(objHandle: HCkSpider;
index: Integer): PWideChar; stdcall;
Returns the Nth URL in the already-spidered URL list. Indexing begins at 0.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topGetUnspideredUrl
index: Integer;
outStr: HCkString): wordbool; stdcall;
function CkSpider__getUnspideredUrl(objHandle: HCkSpider;
index: Integer): PWideChar; stdcall;
Returns the Nth URL in the unspidered URL list. Indexing begins at 0.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topGetUrlDomain
url: PWideChar;
outStr: HCkString): wordbool; stdcall;
function CkSpider__getUrlDomain(objHandle: HCkSpider;
url: PWideChar): PWideChar; stdcall;
Returns the domain name part of a URL. For example, if the URL is "https://www.chilkatsoft.com/test.asp", then "www.chilkatsoft.com" is returned.
Returns True for success, False for failure.
See the notes about PWideChar memory ownership and validity.
topInitialize
domain: PWideChar) stdcall;
Initializes the object 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.
LoadTaskCaller
RecrawlLast
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.
topRecrawlLastAsync (1)
Creates an asynchronous task to call the RecrawlLast method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.
Returns nil on failure
topSkipUnspidered
index: Integer) stdcall;
Moves a URL from the unspidered list to the spidered list. This allows an application to skip a specific URL.
topSleepMs
numMilliseconds: Integer) stdcall;
Suspends the execution of the current thread until the time-out interval elapses.
topEvents
Chilkat supports event callbacks for the Delphi DLL starting in version 9.5.0.82.
AbortCheck
Provides the opportunity for a method call to be aborted. The AbortCheck event is fired periodically based on the value of the HeartbeatMs property. If HeartbeatMs is 0, then no AbortCheck events will fire. As an example, to fire 5 AbortCheck events per second, set the HeartbeatMs property equal to 200. Return True to abort; return False to continue (not abort)
PercentDone
Provides the percentage completed for any method that involves network communications or time-consuming processing (assuming it is a method where a percentage completion can be measured). This event is only fired when it is possible to know a percentage completion, and when it makes sense to express the operation as a percentage completed. The pctDone argument will have a value from 1 to 100. For operations (Chilkat method calls) that complete very quickly, the number of PercentDone callbacks will vary, but the final callback should have a value of 100. For long running operations, no more than one callback per percentage point will occur (for example: 1, 2, 3, ... 98, 99, 100).
The PercentDone callback counts as an AbortCheck event. For method calls that complete quickly such that PercentDone events fire, it may be that AbortCheck events don't fire because the opportunity to abort is already provided in the PercentDone callback. For time consuming operations, where the amount of time between PercentDone callbacks are long, AbortCheck callbacks may be used to allow for the operation to be aborted in a more responsive manner.
Return True to abort; return False to continue (not abort)
ProgressInfo
A general name/value event that provides information about what is happening during a method call. To find out what information is available, write code to handle this event and log the name/value pairs. Most are self-explanatory.
TaskCompleted
Called in the background thread when an asynchronous task completes.