4 In order to ensure thread safety it is important that all of the objects and interfaces of URI objects are immutable.
5 If you are implementing a new URI type, please make sure that none of the type's public methods change the URL.
9 - URI - Uniform Resource Identifier
10 - URL - Uniform Resource Locator
12 These two terms are used interchangeably throughout the codebase and essentially represent the same thing - a string of characters that represents a specific resource.
16 While we could simply pass strings around and leave it to the final consumer to deal with it, that creates a burden for the consumer and would probably be inefficient. Instead we parse the string into a nsIURI object as soon as possible and pass that object through function calls. This allows the consumer to easily extract only the part of the string they are interested in (eg. the hostname or the path).
19 - [nsIURI](https://searchfox.org/mozilla-central/source/netwerk/base/nsIURI.idl)
20 - This is the most important interface for URI parsing. It contains a series of readonly attributes that consumers can use to extract information from the URI.
21 - [nsIURL](https://searchfox.org/mozilla-central/source/netwerk/base/nsIURL.idl)
22 - Defines a structure for the URI's path (directory, fileName, fileBaseName, fileExtension)
23 - [nsIFileURL](https://searchfox.org/mozilla-central/source/netwerk/base/nsIFileURL.idl)
24 - Has a file attribute of type `nsIFile`
25 - Used for local protocols to access the file represented by the `nsIURI`
26 - [nsIMozIconURI](https://searchfox.org/mozilla-central/source/image/nsIIconURI.idl)
27 - Used to represent an icon. Contains additional attributes such as the size and contentType or state of the URL.
28 - [nsIJARURI](https://searchfox.org/mozilla-central/source/modules/libjar/nsIJARURI.idl)
29 - Used to represent a resource inside of a JAR (zip archive) file.
30 - For example `jar:http://www.example.com/blue.jar!/ocean.html` represents the `/ocean.html` resource located inside the `blue.jar` archive that can be fetched via HTTP from example.com.
31 - [nsIStandardURL](https://searchfox.org/mozilla-central/source/netwerk/base/nsIStandardURL.idl)
32 - Defines a few constant flags used to determine the type of the URL. No other attributes.
33 - [nsINestedURI](https://searchfox.org/mozilla-central/source/netwerk/base/nsINestedURI.idl)
34 - Defines `innerURI` and `innermostURI`.
35 - `innermostURI` is just a helper - one could also get it by going through `innerURI` repeatedly until the attribute no longer QIs to nsINestedURI.
36 - [nsISensitiveInfoHiddenURI](https://searchfox.org/mozilla-central/source/netwerk/base/nsISensitiveInfoHiddenURI.idl)
37 - Objects that implement this interface will have a `getSensitiveInfoHiddenSpec()` method that returns the spec of the URI with sensitive info (such as the password) replaced by the `*` symbol.
39 ### Diagram of interfaces
42 nsISupports <-- nsIURI
45 nsIURI <-- nsIMozIconURI
47 nsISupports <-- nsIStandardURL
48 nsISupports <-- nsINestedURI
49 nsISupports <-- nsISensitiveInfoHiddenURI
54 To ensure thread safety all implementations of nsIURI must be immutable.
55 To change a URI the consumer must call `nsIURI.mutate()` which returns a `nsIMutator`. The `nsIMutator` has several setter methods that can be used change attributes on the concrete object. Once done changing the object, the consumer will call `nsIMutator.finalize()` to obtain an immutable `nsIURI`.
57 - [nsIURIMutator](https://searchfox.org/mozilla-central/source/netwerk/base/nsIURIMutator.idl)
58 - This interface contains a series of setters that can be used to mutate and/or construct a `nsIURI`
61 ### Additional interfaces
63 - [nsISerializable](https://searchfox.org/mozilla-central/source/xpcom/ds/nsISerializable.idl)
64 - Allows us to serialize and deserialize URL objects into strings for persistent storage (such as session restore).
67 - [nsStandardURL](https://searchfox.org/mozilla-central/source/netwerk/base/nsStandardURL.h)
68 - [SubstitutingURL](https://searchfox.org/mozilla-central/source/netwerk/protocol/res/SubstitutingURL.h)
69 - overrides nsStandardURL::GetFile to provide nsIFile resolution.
70 - This allows us to map URLs such as `resource://gre/actors/RemotePageChild.jsm` to the actual file on the disk.
71 - [nsMozIconURI](https://searchfox.org/mozilla-central/source/image/decoders/icon/nsIconURI.h)
72 - Used to represent icon URLs
73 - [nsSimpleURI](https://searchfox.org/mozilla-central/source/netwerk/base/nsSimpleURI.h)
74 - Used for simple URIs that normally don't have an authority (username, password, host, port)
75 - [nsSimpleNestedURI](https://searchfox.org/mozilla-central/source/netwerk/base/nsSimpleNestedURI.h)
76 - eg. `view-source:http://example.com/path`
77 - Normally only the extra scheme of the nestedURI is relevant (eg. `view-source:`)
78 - Most of the getter/setters are delegated to the innerURI
79 - [nsNestedAboutURI](https://searchfox.org/mozilla-central/source/netwerk/protocol/about/nsAboutProtocolHandler.h)
80 - Similar to nsSimpleNestedURI, but has an extra `mBaseURI` member that allows us to propagate the base URI to about:blank correctly`
81 - [BlobURL](https://searchfox.org/mozilla-central/source/dom/file/uri/BlobURL.h)
82 - Used for javascript blobs
83 - Similar to nsSimpleURI, but also has a revoked field.
84 - [DefaultURI](https://searchfox.org/mozilla-central/source/netwerk/base/DefaultURI.h)
85 - This class wraps an object parsed by the `rust-url` crate.
86 - While not yet enabled by default, due to small bugs in that parser, the plan is to eventually use this implementation for all _unknown protocols_ that don't have their own URL parser.
87 - [nsJSURI](https://searchfox.org/mozilla-central/source/dom/jsurl/nsJSProtocolHandler.h)
88 - Used to represent javascript code (eg. `javascript:alert('hello')`)
89 - [nsJARURI](https://searchfox.org/mozilla-central/source/modules/libjar/nsJARURI.h)
90 - Used to represent resources inside of JAR files.
92 ### Diagram of implementations
96 nsSimpleURI o-- BlobURL
97 nsIMozIconURI o-- nsMozIconURI
98 nsIFileURL o-- nsStandardURL
99 nsIStandardURL o-- nsStandardURL
100 nsISensitiveInfoHiddenURI o-- nsStandardURL
101 nsStandardURL o-- SubstitutingURL
102 nsIURI o-- nsSimpleURI
103 nsSimpleURI o-- nsSimpleNestedURI
104 nsSimpleNestedURI o-- nsNestedAboutURI
106 nsIURI o-- DefaultURI
108 nsSimpleURI o-- nsJSURI
110 nsINestedURI o-- nsJARURI
111 nsIJARURI o-- nsJARURI
114 ## Class and interface diagram
118 nsISupports <-- nsIURI
120 nsIURL <-- nsIFileURL
121 nsIURI <-- nsIMozIconURI
123 nsISupports <-- nsIStandardURL
124 nsISupports <-- nsINestedURI
125 nsISupports <-- nsISensitiveInfoHiddenURI
129 nsSimpleURI o-- BlobURL
130 nsSimpleURI o-- nsJSURI
131 nsIMozIconURI o-- nsMozIconURI
132 nsIFileURL o-- nsStandardURL
133 nsIStandardURL o-- nsStandardURL
134 nsISensitiveInfoHiddenURI o-- nsStandardURL
135 nsStandardURL o-- SubstitutingURL
136 nsIURI o-- nsSimpleURI
137 nsINestedURI o-- nsJARURI
138 nsIJARURI o-- nsJARURI
139 nsSimpleURI o-- nsSimpleNestedURI
140 nsSimpleNestedURI o-- nsNestedAboutURI
141 nsIURI o-- DefaultURI