Changes for page Technical details
Last modified by lzehl on 2021/07/05 18:57
Summary
-
Page properties (1 modified, 0 added, 0 removed)
Details
- Page properties
-
- Content
-
... ... @@ -10,123 +10,71 @@ 10 10 Please find below a documentation of the layout and requirements needed to keep the openMINDS modularity, the syntax of the openMINDS schema template, as well as the openMINDS integration pipeline. 11 11 ))) 12 12 13 -=== The openMINDSumbrella ===13 +=== Overview of the openMINDS layout === 14 14 15 15 (% style="text-align: justify;" %) 16 16 In summary, openMINDS is the overall umbrella for a set of distributed GitHub repositories, each defining a particular metadata model for neuroscience research products. 17 17 18 +=== The openMINDS schema template syntax === 19 + 18 18 (% style="text-align: justify;" %) 19 - The main (or central)[[openMINDSGitHub repository>>https://github.com/HumanBrainProject/openMINDS||rel="noopenernoreferrer" target="_blank"]] ingestsall these GitHub repositoriesas[[git-submodules>>https://git-scm.com/docs/git-submodule||rel="noopenernoreferrer"target="_blank"]].FurthermoreitdefinestheopenMINDS vocabulary (**##vocab##**)usedfor**##types##** and **##properties##** across all schemas independent of their originalrepository(cf. below). And lastbutnot least, it holdstheschemarepresentationsfor all supported metadata formatscreatedbytheopenMINDSintegrationpipeline (cf.below).21 +All openMINDS metadata models use a light-weighted schema template syntax for defining the metadata. The correspondingly formatted schema files use the extension: **##.schema.tpl.json##**. 20 20 21 21 (% style="text-align: justify;" %) 22 - Forthistoworksmoothlyforthe existing,but alsofor allnewopenMINDSmetadatamodels,the correspondingopenMINDSsubmodules(GitHubrepositories)have tomeet the followingrequirements:24 +Although, as the file extension suggests, this openMINDS schema template syntax is inspired by JSON-Schema, it facilitates or even excludes technical aspects that are generally expected for the openMINDS schemas making it more human-readable, especially for untrained eyes. Behind the scenes, within the openMINDS integration pipeline (cf. below), this schema template syntax is then interpreted and flexibly translated to various formal metadata formats (e.g., JSON-Schema). 23 23 24 -(% style="text-align:justify" %) 25 -* The openMINDS metadata model has to be located on a **public GitHub repository** and published under an **MIT license**. 26 -* The GitHub repository should have at least one **version branch** (e.g. "v1"). 27 -* The version branch should have the following **main directory folders**: **##schemas##** (required), **##tests##** (recommended), **##examples##** (recommended), and **##img##** (optional). 28 -* The **##schemas##** folder should contain the schemas of that metadata model implemented in the **openMINDS schema template syntax** (cf. below). The directory of the schemas can be further structured or flat. 29 -* The **##tests##** folder should contain test-instances (JSON-LDs) for the schemas in a flat directory. The file names for these test-instances should follow the convention of **##<<XXX>>-<<YYY>>.jsonld##** for files that should pass the tests, and **##<<XXX>>-<<YYY>>-nok.jsonld##** for files that should fail the test. In both cases, **##<<XXX>>##** should be replaced with the label of the schema that is tested, and **##<<YYY>>##** with a user defined label for what aspect is tested (e.g., **##person-withoutContactInformation.jsonld##**). 30 -* The **##examples##** folder should contain examples for valid instance collections for that metadata model. Each example should receive its own directory (folder) with a **##README.md##** describing the example, and an **##metadataCollection##** subfolder containing the openMINDS instances (JSON-LDs). This subfolder can be further structured to group related instances. 31 - 32 -=== The openMINDS vocabulary === 33 - 34 34 (% style="text-align: justify;" %) 35 - ((%style="color:#7f8c8d"%)//**coming soon**//(%%))27 +Despite the simplification in comparison to JSON-Schema, the openMINDS schema templates are also, at the core, specially formatted JSON files using a particular syntax, meaning special key-value pairs that define the validation rules of a schema. 36 36 37 -=== The openMINDS schema template syntax === 38 - 39 39 (% style="text-align: justify;" %) 40 - All openMINDSmetadatamodelsusea light-weightedschema template syntaxfor definingtheexpectedmetadata. Thecorrespondinglyformattedschemafilesusethextension: **##.schema.tpl.json##**.30 +Please find in the following a full documentation of the openMINDS schema template syntax and how the key-value pairs need to be defined and interpreted. 41 41 42 42 (% style="text-align: justify;" %) 43 - Although,as the file extension suggests,thisopenMINDS schema template syntax is inspired by JSON-Schema, it facilitatesor evenexcludestechnical aspects that are generally expectedfortheopenMINDS schemas making them more human-readable, especially for untrained eyes. Behindthecenes,within the openMINDS integration pipeline (cf. below), this schema template syntax is then interpreted and flexibly translated to various formal metadata formats (e.g., JSON-Schema).33 +===== Target & context templates ===== 44 44 45 45 (% style="text-align: justify;" %) 46 - Despite the simplificationin comparisonto JSON-Schema,the openMINDSschema templatesarealso, atthecore,speciallyformattedJSONfilesusingarticularsyntax,meaning special key-valuepairsthat definethevalidationrules of a schema.36 +An openMINDS schema //HAS TO HAVE// a **##"_type"##** to be recognized as **target template**. In other words, the **##"_type"##** is used to define the openMINDS namespace of a corresponding schema using the following naming convention: 47 47 48 48 (% style="text-align: justify;" %) 49 - Pleasefindinthe following a fulldocumentationof theopenMINDSschematemplate syntax and how it's key-value pairsneed to be definedand interpreted.39 +**##"_type": "https:~/~/openminds.ebrains.eu/<<schema-model>>/<<schema-name>>"##** 50 50 51 51 (% style="text-align: justify;" %) 52 - =====Target&concept templates=====42 +where **##<<schema-model>>##** has to be replaced with the label of the openMINDS metadata model the corresponding schema belongs to and **##<<schema-name>>##** exchanged with the label of that schema. 53 53 54 54 (% style="text-align: justify;" %) 55 - Sameas inJSON-Schema, allopenMINDS schema templatesdefinetheexpectedname(writtenin**##lowerCamelCase##**) and value of the metadata,typically called property,underthekey **##properties##**asnesteddictionaries. Furthermore,thenames of obligatory metadatacanbelisted underthekey **##required##**. Herea generalizedexample:45 +If an openMINDS schema template file //DOES NOT// define a **##"_type"##**, it is interpreted as a **context template** which //HAS TO BE// extended to a target template. 56 56 57 -{{code language="json"}} 58 -{ 59 - "properties": { 60 - "propertyNameA": {}, 61 - "propertyNameB": {}, 62 - "propertyNameC": {} 63 - }, 64 - "required": [ 65 - "propertyNameA", 66 - "propertyNameC" 67 - ] 68 -} 69 -{{/code}} 70 - 71 71 (% style="text-align: justify;" %) 72 - In addition,an openMINDSschema//hastohave//a key **##"_type"##**toberecognizedas**target template**.Inotherwords, the**##"_type"##**is usedtodefine theopenMINDSnamespaceofacorresponding schemausingaparticularnamingconvention. Hereagaina generalizedexample:48 +Context templates are and should be used when multiple openMINDS schemas (target templates) have the same subset of properties. This common subset of properties can then be defined within a single context schema instead of each target template which facilitates the long-term maintenance of these properties. 73 73 74 -{{code language="json"}} 75 -{ 76 - "_type": "https:~/~/openminds.ebrains.eu/<<schema-model>>/<<schema-name>>", 77 - "properties": {} 78 -} 79 -{{/code}} 80 - 81 81 (% style="text-align: justify;" %) 82 - Note that**##<<schema-model>>##**hastobereplacedwiththelabeloftheopenMINDS metadatamodelowhichthecorrespondingschemabelongsto,and **##<<schema-name>>##** hastobereplacedwith the correspondingname oftheschema(writtenin**##CamelCase##**).51 +To define that a target template is the extension of a context template, the target template can state under **##"_extends"##** the relative path to the context template. Note that this requires the context and corresponding target templates to be located in the same openMINDS metadata model repository. 83 83 84 84 (% style="text-align: justify;" %) 85 - Ifan openMINDSschematemplate //does not// definea key **##"_type"##** (as in the first exampleabove), its interpreted asa **concept template** which //has to be// extended to a target template.54 +===== String properties ===== 86 86 87 87 (% style="text-align: justify;" %) 88 - Concept templates are and should be used whenmultiple target templates have the same subset of properties, because they facilitate the long-termmaintenance of those shared properties: Insteadof defining the same properties repeatedly within multiple target templates, the common subset can be defined within a single concept template and passed on to all extending target templates.57 +(//**coming soon**//) 89 89 90 90 (% style="text-align: justify;" %) 91 - Todefine that a target templateis the extension of a concept template, the target template can state under **##"_extends"##** the relative path to theconcept template. For example,the openMINDS core target template **##Dataset##** extends the core concept template **##researchProduct##** asindicatedhere:60 +===== Numerical properties ===== 92 92 93 -{{code language="json"}} 94 -{ 95 - "_type": "https:~/~/openminds.ebrains.eu/core/Dataset", 96 - "_extends": "products/researchProduct.schema.tpl.json" 97 -} 98 -{{/code}} 99 - 100 100 (% style="text-align: justify;" %) 101 - Note that thisconvention requires the concept and corresponding target templates to be locatedinthe same openMINDS metadata model repository. Note also that for properties, the followingrulesapply for target and concept template:63 +(//**coming soon**//) 102 102 103 -1. A concept template has to define some properties which will be inherited by all extending target templates. 104 -1. If a concept template additionally states that some of these properties are required, all extending target templates will require the same properties. 105 -1. A target template can require properties of the concept template, that are not explicitly required within the concept template. In such a case, the other target templates extending the same concept template will not require those properties. 106 -1. A target template can (but does not have to) define and require additional properties that were not defined and required in the concept template. These additionally defined and required properties will not be shared with the other target templates extending the same concept template. 107 - 108 108 (% style="text-align: justify;" %) 109 - Howto define the expectedvalue of aproperty will beexplained for the different property typesin the following sections.66 +===== Object properties ===== 110 110 111 111 (% style="text-align: justify;" %) 112 - ===== Definingexpected values=====69 +(//**coming soon**//) 113 113 114 114 (% style="text-align: justify;" %) 115 - Theexpected value of a propertycan be defined in large parts in the same wayasin JSON-Schema, with some openMINDS syntax specific simplifications and modifications.72 +===== Property arrays ===== 116 116 117 117 (% style="text-align: justify;" %) 118 -On the first level, the **##"type"##** of the expected property value needs to be defined. In principle, the openMINDS template syntax supports the same value types as JSON-Schema Draft 7.0, meaning: 119 -+ **##"string"##** 120 -+ **##"number"##** 121 -+ **##"integer"##** 122 -+ **##"array"##** 123 -+ **##"boolean"##** 124 -+ **##"null"##** 125 -+ **##"object"##** 75 +(//**coming soon**//) 126 126 127 -Also very similar to JSON-Schema, additional type-specific keys can be used to set further requirements for the expected value. H 128 128 129 - 130 130 === The openMINDS integration pipeline === 131 131 132 132 (//**coming soon**//)