Search settings; Web History : Advanced search Language tools. ![]() Tiny, powerful, free mathematical program with WYSIWYG editor and complete units of measurements support.Oracle / PLSQL: VIEW. This Oracle tutorial explains how to create, update, and drop Oracle VIEWS with syntax and examples. HTTP Extensions for Web Distributed Authoring and Versioning (Web. DAV)This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the “Internet Official Protocol Standards” (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright . All Rights Reserved. Web Distributed Authoring and Versioning (Web. DAV) consists of a set of methods, headers, and content- types ancillary to HTTP/1. URL namespace manipulation, and resource locking (collision avoidance). RFC 2. 51. 8 was published in February 1. RFC 2. 51. 8 with minor revisions mostly due to interoperability experience. This document describes an extension to the HTTP/1. Web content authoring operations. This extension provides a coherent set of methods, headers, request entity body formats, and response entity body formats that provide operations for. This prevents the . That work was done in a separate document, . General considerations for handling HTTP requests and responses in Web. DAV are found in Section 8. This specification defines extra status codes developed for Web. DAV methods (Section 1. HTTP status codes (Section 1. Web. DAV. Since some Web. DAV methods may operate over many resources, the Multi- Status response (Section 1. Finally, this version of Web. DAV introduces precondition and postcondition (Section 1. XML elements in error response bodies. This specification contains DTD and text definitions of all properties (Section 1. XML elements (Section 1. Web. DAV includes a few special rules on extending Web. DAV XML marshalling in backwards- compatible ways (Section 1. Since this augmented BNF uses the basic production rules provided in Section 2. Note this is not the standard BNF syntax used in other RFCs. These terms (and the distinction between them) are defined in . Since a resource can represent items that are not network retrievable, as well as those that are, it is possible for a resource to have zero, one, or many URI mappings. Mapping a resource to an . Formally, as defined in Section 3. Formally, a resource that contains a set of mappings between path segments and resources and meets the requirements defined in Section 5. Formally, a resource referenced by a path segment mapping contained in the collection. Formally, an internal member of the collection, or, recursively, a member of an internal member. For example, the live property DAV: getcontentlength has its value, the length of the entity returned by a GET request, automatically calculated by the server. The server only records the value of a dead property; the client is responsible for maintaining the consistency of the syntax and semantics of a dead property. Lock tokens are the only state tokens defined in this specification. Properties are data about data. For example, a 'subject' property might allow for the indexing of all resources by their subject, and an 'author' property might allow for the discovery of what authors have written which documents. The name of a property identifies the property's syntax and semantics, and provides an address by which to refer to its syntax and semantics. A live property has its syntax and semantics enforced by the server. Live properties include cases where a) the value of a property is protected and maintained by the server, and b) the value of the property is maintained by the client, but the server performs syntax checking on submitted values. All instances of a given live property MUST comply with the definition associated with that property name. A dead property has its syntax and semantics enforced by the client; the server merely records the value of the property verbatim. However, in distributed authoring environments, a relatively large number of properties are needed to describe the state of a resource, and setting/returning them all through HTTP headers is inefficient. Thus, a mechanism is needed that allows a principal to identify a set of properties in which the principal is interested and to set or retrieve just those properties. XML's self- describing nature allows any property's value to be extended by adding elements. Clients will not break when they encounter extensions because they will still have the data specified in the original schema and MUST ignore elements they do not understand. XML's support for multiple human languages, using the . Note that xml: lang scope is recursive, so an xml: lang attribute on any element containing a property name element applies to the property value unless it has been overridden by a more locally scoped attribute. Note that a property only has one value, in one language (or language MAY be left undefined); a property does not have multiple values in different languages or a single value in multiple languages. The simplest example is an empty property, which is different from a property that does not exist. The value may be any kind of well- formed XML content, including both text- only and mixed content. Servers MUST preserve the following XML Information Items (using the terminology from . The above rules would also apply by default to live properties, unless defined otherwise. Whitespace in property values is significant. In this case, clients should consider using a text- only property value by escaping all characters that have a special meaning in XML parsing. Thus, if a property A and a property A/B exist on a resource, there is no recognition of any relationship between the two properties. It is expected that a separate specification will eventually be produced that will address issues relating to hierarchical properties. For these resources, there presumably exists source code somewhere governing how that resource is generated. The relationship of source files to output HTTP resources may be one to one, one to many, many to one, or many to many. There is no mechanism in HTTP to determine whether a resource is even dynamic, let alone where its source files exist or how to author them. Although this problem would usefully be solved, interoperable Web. DAV implementations have been widely deployed without actually solving this problem, by dealing only with static resources. Thus, the source vs. The purpose of a collection resource is to model collection- like objects (e. The root, or top- level collection of the namespace under consideration, is exempt from the previous rule. The top- level collection of the namespace under consideration is not necessarily the collection identified by the absolute path '/' - - it may be identified by one or more path segments (e. However, certain Web. DAV methods are prohibited from producing results that cause namespace inconsistencies. For example, a resource could be identified by multiple HTTP URLs. Some HTTP methods apply only to a collection, but some apply to some or all of the resources inside the container defined by the collection. When the scope of a method is not clear, the client can specify what depth to apply. Depth can be either zero levels (only the collection), one level (the collection and directly contained resources), or infinite levels (the collection and all contained resources recursively). In this document, a resource B will be said to be contained in the collection resource A if there is a path segment mapping that maps to B and that is contained in A. A collection MUST contain at most one mapping for a given path segment, i. A collection MAY have additional state such as entity bodies returned by GET. So, if resource B with URL . This allows a server to treat a set of segments as equivalent (i. For example, a server that performs case- folding on segments will treat the segments . A client can then use any of these segments to identify the resource. Note that a PROPFIND result will select one of these equivalent segments to identify the mapping, so there will be one PROPFIND response element per mapping, not one per segment in the mapping. For example, if resource X with URL . In this case, it SHOULD return a Content- Location header in the response, pointing to the URL ending with the . For example, if a client invokes a method on http: //example. Content- Location header with the value http: //example. Wherever a server produces a URL referring to a collection, the server SHOULD include the trailing slash. In general, clients SHOULD use the trailing slash form of collection names. If clients do not use the trailing slash form the client needs to be prepared to see a redirect response. Clients will find the DAV: resourcetype property more reliable than the URL to find out if a resource is a collection. For example, if an OPTIONS response from . For instance, . Similarly, a dynamically- generated page might have a URL mapping from . An example for this case are servers that support multiple alias URLs for each Web. DAV- compliant resource. A server may implement case- insensitive URLs, thus . In cases where a server treats a set of segments as equivalent, the server MUST expose only one preferred segment per mapping, consistently chosen, in PROPFIND responses. Using a lock, an authoring client can provide a reasonable guarantee that another principal will not modify a resource while it is being edited. In this way, a client can prevent the . This document defines locking for only one access type, write. However, the syntax is extensible, and permits the eventual specification of locking for other access types. Later sections will provide more detail on some of the concepts and refer back to these model statements. Normative statements related to LOCK and UNLOCK method handling can be found in the sections on those methods, whereas normative statements that cover any method are gathered here. If at the time of the request, the URL is not mapped to a resource, a new empty resource is created and directly locked. An exclusive lock (Section 6. A server MUST NOT create conflicting locks on a resource.
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