aermicioi.aedi.storage.aggregate

1 /**
2 
3 License:
4 	Boost Software License - Version 1.0 - August 17th, 2003
5 
6     Permission is hereby granted, free of charge, to any person or organization
7     obtaining a copy of the software and accompanying documentation covered by
8     this license (the "Software") to use, reproduce, display, distribute,
9     execute, and transmit the Software, and to prepare derivative works of the
10     Software, and to permit third-parties to whom the Software is furnished to
11     do so, all subject to the following:
12 
13     The copyright notices in the Software and this entire statement, including
14     the above license grant, this restriction and the following disclaimer,
15     must be included in all copies of the Software, in whole or in part, and
16     all derivative works of the Software, unless such copies or derivative
17     works are solely in the form of machine-executable object code generated by
18     a source language processor.
19 
20     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21     IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22     FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
23     SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
24     FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
25     ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26     DEALINGS IN THE SOFTWARE.
27 
28 Authors:
29 	Alexandru Ermicioi
30 **/
31 module aermicioi.aedi.storage.aggregate_locator;
32 
33 import aermicioi.aedi.exception.not_found_exception;
34 import aermicioi.aedi.storage.locator;
35 import aermicioi.aedi.util.typecons : Pair, pair;
36 import std.conv : to;
37 import std.range.interfaces;
38 
39 /**
40 An implementation of AggregateLocator.
41 **/
42 @safe class AggregateLocatorImpl(Type = Object, KeyType = string, LocatorKeyType = KeyType) :
43     MutableAggregateLocator!(Type, KeyType, LocatorKeyType) {
44 
45     protected {
46 
47         Locator!(Type, KeyType)[LocatorKeyType] locators;
48     }
49 
50     public {
51 
52         /**
53         Add a Locator by key.
54 
55         Params:
56         	key = key by which to identify the locator.
57         	locator = the Locator that will be added to AggregateLocator
58         **/
59         AggregateLocatorImpl!(Type, KeyType, LocatorKeyType) set(Locator!(Type, KeyType) locator, LocatorKeyType key) {
60 
61             this.locators[key] = locator;
62 
63             return this;
64         }
65 
66         /**
67         Removes a Locator by key.
68 
69         Params:
70         	key = the identity of locator that should be removed.
71         **/
72         AggregateLocatorImpl!(Type, KeyType, LocatorKeyType) remove(LocatorKeyType key) {
73 
74             this.locators.remove(key);
75 
76             return this;
77         }
78 
79         /**
80 		Get an Type that is associated with key.
81 
82 		Params:
83 			identity = the element id.
84 
85 		Throws:
86 			NotFoundException in case if the element wasn't found.
87 
88 		Returns:
89 			Type element if it is available.
90 		**/
91         Type get(KeyType identity) {
92 
93             foreach (locator; this.locators) {
94 
95                 if (locator.has(identity)) {
96                     return locator.get(identity);
97                 }
98             }
99 
100             if ((identity in this.locators) !is null) {
101                 auto result = (() scope @trusted => cast(Type) this.locators[identity])();
102 
103                 if (result !is null) {
104                     return result;
105                 }
106             }
107 
108             throw new NotFoundException("Could not find component with ${identity} identity.", identity.to!string);
109         }
110 
111         /**
112         Check if an element is present in Locator by key id.
113 
114         Note:
115         	This check should be done for elements that locator actually contains, and
116         	not in chained locator (when locator is also a DelegatingLocator) for example.
117         Params:
118         	identity = identity of element.
119 
120     	Returns:
121     		bool true if an element by key is present in Locator.
122         **/
123         bool has(in KeyType identity) inout {
124 
125             if ((identity in this.locators) !is null) {
126                 return true;
127             }
128 
129             foreach (locator; this.locators) {
130 
131                 if (locator.has(identity)) {
132                     return true;
133                 }
134             }
135 
136             return false;
137         }
138 
139         /**
140         Get a specific locator.
141 
142         Params:
143             key = the locator identity.
144         **/
145         Locator!(Type, KeyType) getLocator(LocatorKeyType key) {
146 
147             if (this.hasLocator(key)) {
148                 return this.locators[key];
149             }
150 
151             throw new NotFoundException("Could not find any locator with identity ${identity}", key);
152         }
153 
154         /**
155         Get all locators in aggregate locator
156 
157         Returns:
158         	InputRange!(Pair!(Locator!(Type, KeyType), LocatorKeyType)) a range of locator => identity
159         **/
160         InputRange!(Pair!(Locator!(Type, KeyType), LocatorKeyType)) getLocators() {
161             import std.algorithm : map;
162 
163             return this.locators.byKeyValue.map!(
164                 a => pair(a.value, a.key)
165             ).inputRangeObject;
166         }
167 
168         /**
169         Check if aggregate locator contains a specific locator.
170 
171         Params:
172         	key = the identity of locator in aggregate locator
173         **/
174         bool hasLocator(LocatorKeyType key) inout {
175 
176             return (key in this.locators) !is null;
177         }
178     }
179 }