View source for Help:JSON format

{{Result format
 |format name=json
 |authors=James Hong Kong, Jeroen De Dauw, Fabian Howahl 
 |minimum version=1.4.2
 |compatibility change=1.8.0
 |maximum version=still supported
 |further reqs=none
 |component=Semantic MediaWiki
 |categories=export, plaintext
 |description=Outputs results in JSON-based serialisations.
 |class=SMWJSON,SMWJSONResultPrinter,SMWExportPrinter
 |collection=json
}}
The [[Help:Result formats|result format]] '''json''' is used to produce links to [[wp:en:JSON|JSON]] files. The export syntax has changed starting with {{Release|1.8.0}}. 

The change in the export syntax was necessary to ensure a higher validity among export formats, a reliance on available serialization methods, and elimination of specific error prone conversion procedures.

{{Callout
 |{{Release|3.0.0}} introduced a set of predefined classes supporting a datatable output[[CiteRef::gh:smw:2420]][[CiteRef::gh:smw:2718]] which also allows for JSON export via {{ResultFormat|Table}}.
 |info
}}

== Parameters ==
=== General ===
{{#smwdoc:json|parameters=base}}

=== Format specific ===
{{#smwdoc:json|parameters=specific}}

Available values for parameters:
* <code>type</code>: <code>full</code> (default) and <code>simple</code>

{{Callout
 |{{Release|3.0.0}} brought the "<code>type</code>"[[CiteRef::gh:smw:2690]] parameter.
 |info
}}

== Examples ==
=== Default ===
; Syntax
<pre>
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
}}
</pre>
; Result as table
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
}}
; Result as json
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
}}
; Display of result as json (printed)
<syntaxhighlight lang="json">
{"printrequests":[{"label":"City","key":"","redi":"","typeid":"_wpg","mode":2,"format":false},{"label":"Population","key":"Population","redi":"","typeid":"_num","mode":1,"format":""},{"label":"Area","key":"Has_area","redi":"","typeid":"_qty","mode":1,"format":"km\u00b2"}],"results":{"Demo:Berlin":{"printouts":{"Population":[3520061],"Area":[{"value":891.85,"unit":"km\u00b2"}]},"fulltext":"Demo:Berlin","fullurl":"https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Berlin","namespace":202,"exists":"1","displaytitle":"Berlin"},"Demo:Cologne":{"printouts":{"Population":[1080394],"Area":[{"value":405.02,"unit":"km\u00b2"}]},"fulltext":"Demo:Cologne","fullurl":"https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Cologne","namespace":202,"exists":"1","displaytitle":"Cologne"},"Demo:Frankfurt":{"printouts":{"Population":[679664],"Area":[{"value":248.31,"unit":"km\u00b2"}]},"fulltext":"Demo:Frankfurt","fullurl":"https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Frankfurt","namespace":202,"exists":"1","displaytitle":"Frankfurt"},"Demo:Munich":{"printouts":{"Population":[1353186],"Area":[{"value":310.43,"unit":"km\u00b2"}]},"fulltext":"Demo:Munich","fullurl":"https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Munich","namespace":202,"exists":"1","displaytitle":"Munich"},"Demo:Stuttgart":{"printouts":{"Population":[606588],"Area":[{"value":207.36,"unit":"km\u00b2"}]},"fulltext":"Demo:Stuttgart","fullurl":"https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Stuttgart","namespace":202,"exists":"1","displaytitle":"Stuttgart"},"Demo:W\u00fcrzburg":{"printouts":{"Population":[126635],"Area":[{"value":87.63,"unit":"km\u00b2"}]},"fulltext":"Demo:W\u00fcrzburg","fullurl":"https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:W%C3%BCrzburg","namespace":202,"exists":"1","displaytitle":"W\u00fcrzburg"}},"serializer":"SMW\\Serializers\\QueryResultSerializer","version":2,"rows":6}
</syntaxhighlight>

=== Change file name ===
Another file name for exporting the results can be specified by changing the <code>searchlabel</code> parameter:
; Syntax
<pre>
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
 |searchlabel=example
}}
</pre>

; Result
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
 |searchlabel=example
}}

=== Pretty printed output ===
The separator used between results can be listed too in the exported file by setting the <code>prettyprint</code> parameter to "<code>yes</code>": 
; Syntax
<pre>
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
 |prettyprint=yes
}}
</pre>
; Result as table
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
}}
; Result as json
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
 |prettyprint=yes
}}
; Display of result as json (prettyprinted)
<syntaxhighlight lang="json">
{
    "printrequests": [
        {
            "label": "City",
            "key": "",
            "redi": "",
            "typeid": "_wpg",
            "mode": 2,
            "format": false
        },
        {
            "label": "Population",
            "key": "Population",
            "redi": "",
            "typeid": "_num",
            "mode": 1,
            "format": ""
        },
        {
            "label": "Area",
            "key": "Has_area",
            "redi": "",
            "typeid": "_qty",
            "mode": 1,
            "format": "km\u00b2"
        }
    ],
    "results": {
        "Demo:Berlin": {
            "printouts": {
                "Population": [
                    3520061
                ],
                "Area": [
                    {
                        "value": 891.85,
                        "unit": "km\u00b2"
                    }
                ]
            },
            "fulltext": "Demo:Berlin",
            "fullurl": "https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Berlin",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Berlin"
        },
        "Demo:Cologne": {
            "printouts": {
                "Population": [
                    1080394
                ],
                "Area": [
                    {
                        "value": 405.02,
                        "unit": "km\u00b2"
                    }
                ]
            },
            "fulltext": "Demo:Cologne",
            "fullurl": "https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Cologne",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Cologne"
        },
        "Demo:Frankfurt": {
            "printouts": {
                "Population": [
                    679664
                ],
                "Area": [
                    {
                        "value": 248.31,
                        "unit": "km\u00b2"
                    }
                ]
            },
            "fulltext": "Demo:Frankfurt",
            "fullurl": "https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Frankfurt",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Frankfurt"
        },
        "Demo:Munich": {
            "printouts": {
                "Population": [
                    1353186
                ],
                "Area": [
                    {
                        "value": 310.43,
                        "unit": "km\u00b2"
                    }
                ]
            },
            "fulltext": "Demo:Munich",
            "fullurl": "https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Munich",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Munich"
        },
        "Demo:Stuttgart": {
            "printouts": {
                "Population": [
                    606588
                ],
                "Area": [
                    {
                        "value": 207.36,
                        "unit": "km\u00b2"
                    }
                ]
            },
            "fulltext": "Demo:Stuttgart",
            "fullurl": "https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:Stuttgart",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Stuttgart"
        },
        "Demo:W\u00fcrzburg": {
            "printouts": {
                "Population": [
                    126635
                ],
                "Area": [
                    {
                        "value": 87.63,
                        "unit": "km\u00b2"
                    }
                ]
            },
            "fulltext": "Demo:W\u00fcrzburg",
            "fullurl": "https:\/\/www.semantic-mediawiki.org\/wiki\/Demo:W%C3%BCrzburg",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "W\u00fcrzburg"
        }
    },
    "serializer": "SMW\\Serializers\\QueryResultSerializer",
    "version": 2,
    "rows": 6
}
</syntaxhighlight>

=== Simple output ===
To export a file that only contains a bare minimum of data the <code>type</code> parameter needs to be set to "<code>simple</code>". Using <code>mainlabel=-</code> will allow to reduce the list even further.
; Syntax
<pre>
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
 |type=simple
 |prettyprint=yes
}}
</pre>
; Result as table
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
}}
; Result as json (simple - prettyprinted)
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
 |type=simple
 |prettyprint=yes
}}
; Display of result as json (simple - prettyprinted)
<syntaxhighlight lang="json">
{
    "Berlin#202##": {
        "City": [
            "Demo:Berlin"
        ],
        "Population": [
            "3520061"
        ],
        "Area": [
            "891.85 km\u00b2"
        ]
    },
    "Cologne#202##": {
        "City": [
            "Demo:Cologne"
        ],
        "Population": [
            "1080394"
        ],
        "Area": [
            "405.02 km\u00b2"
        ]
    },
    "Frankfurt#202##": {
        "City": [
            "Demo:Frankfurt"
        ],
        "Population": [
            "679664"
        ],
        "Area": [
            "248.31 km\u00b2"
        ]
    },
    "Munich#202##": {
        "City": [
            "Demo:Munich"
        ],
        "Population": [
            "1353186"
        ],
        "Area": [
            "310.43 km\u00b2"
        ]
    },
    "Stuttgart#202##": {
        "City": [
            "Demo:Stuttgart"
        ],
        "Population": [
            "606588"
        ],
        "Area": [
            "207.36 km\u00b2"
        ]
    },
    "W\u00fcrzburg#202##": {
        "City": [
            "Demo:W\u00fcrzburg"
        ],
        "Population": [
            "126635"
        ],
        "Area": [
            "87.63 km\u00b2"
        ]
    }
}
</syntaxhighlight>


=== Unescaped output ===
To export a file that contains unescaped slashes and multibyte Unicode characters the <code>unescape</code> parameter needs to be set to "<code>yes</code>":
; Syntax
<pre>
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
 |unescape=yes
 |prettyprint=yes
}}
</pre>
; Result as table
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
}}
; Result as json (unescaped - prettyprinted)
{{#ask:
 [[Category:City]]
 [[Located in::Germany]] 
 |?Population
 |?Area#km²=Area
 |mainlabel=City
 |format=json
 |unescape=yes
 |prettyprint=yes
}}
; Display of result as json (unescaped - prettyprinted)
<syntaxhighlight lang="json">
{
    "printrequests": [
        {
            "label": "City",
            "key": "",
            "redi": "",
            "typeid": "_wpg",
            "mode": 2,
            "format": false
        },
        {
            "label": "Population",
            "key": "Population",
            "redi": "",
            "typeid": "_num",
            "mode": 1,
            "format": ""
        },
        {
            "label": "Area",
            "key": "Has_area",
            "redi": "",
            "typeid": "_qty",
            "mode": 1,
            "format": "km²"
        }
    ],
    "results": {
        "Demo:Berlin": {
            "printouts": {
                "Population": [
                    3520061
                ],
                "Area": [
                    {
                        "value": 891.85,
                        "unit": "km²"
                    }
                ]
            },
            "fulltext": "Demo:Berlin",
            "fullurl": "https://www.semantic-mediawiki.org/wiki/Demo:Berlin",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Berlin"
        },
        "Demo:Cologne": {
            "printouts": {
                "Population": [
                    1080394
                ],
                "Area": [
                    {
                        "value": 405.02,
                        "unit": "km²"
                    }
                ]
            },
            "fulltext": "Demo:Cologne",
            "fullurl": "https://www.semantic-mediawiki.org/wiki/Demo:Cologne",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Cologne"
        },
        "Demo:Frankfurt": {
            "printouts": {
                "Population": [
                    679664
                ],
                "Area": [
                    {
                        "value": 248.31,
                        "unit": "km²"
                    }
                ]
            },
            "fulltext": "Demo:Frankfurt",
            "fullurl": "https://www.semantic-mediawiki.org/wiki/Demo:Frankfurt",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Frankfurt"
        },
        "Demo:Munich": {
            "printouts": {
                "Population": [
                    1353186
                ],
                "Area": [
                    {
                        "value": 310.43,
                        "unit": "km²"
                    }
                ]
            },
            "fulltext": "Demo:Munich",
            "fullurl": "https://www.semantic-mediawiki.org/wiki/Demo:Munich",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Munich"
        },
        "Demo:Stuttgart": {
            "printouts": {
                "Population": [
                    606588
                ],
                "Area": [
                    {
                        "value": 207.36,
                        "unit": "km²"
                    }
                ]
            },
            "fulltext": "Demo:Stuttgart",
            "fullurl": "https://www.semantic-mediawiki.org/wiki/Demo:Stuttgart",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Stuttgart"
        },
        "Demo:Würzburg": {
            "printouts": {
                "Population": [
                    126635
                ],
                "Area": [
                    {
                        "value": 87.63,
                        "unit": "km²"
                    }
                ]
            },
            "fulltext": "Demo:Würzburg",
            "fullurl": "https://www.semantic-mediawiki.org/wiki/Demo:W%C3%BCrzburg",
            "namespace": 202,
            "exists": "1",
            "displaytitle": "Würzburg"
        }
    },
    "serializer": "SMW\\Serializers\\QueryResultSerializer",
    "version": 2,
    "rows": 6
}
</syntaxhighlight>

=== More ... ===
* Example page to [[Demo:JSON - datatype export examples|demonstrate the output for different datatypes]]

{{DEFAULTSORTKEY:JSON}}
<div style="display: none">
{{#scite:gh:smw:2690
 |type=pullrequest
 |url=https://github.com/SemanticMediaWiki/SemanticMediaWiki/pull/2690
}}
{{doc.info
 |master page=Help:JSON_format
 |status=effective
 |progress=100
 |priority=2
 |minversion=3.0.0
}}
</div>