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+---
+bookHidden: true
+title: "Model Schema"
+---
+
+# Model Schema
+
+This document describes what is currently implemented in CSIT,
+especially the export side (UTI), not import side (PAL).
+
+## Version
+
+This document is valid for CSIT model version 1.4.0.
+
+It is recommended to use semantic versioning: https://semver.org/
+That means, if the new model misses a field present in the old model,
+bump the major version. If the new model adds a field
+not present in the old model, bump the minor version.
+Any other edit in the implmenetation (or documentation) bumps the patch version.
+If you change value type or formatting,
+consider whether the parser (PAL) understands the new value correctly.
+Renaming a field is the same as adding a new one and removing the old one.
+Parser (PAL) has to know exact major version and minimal minor version,
+and unless bugs, it can ignore patch version and bumped minor version.
+
+## UTI
+
+UTI stands for Unified Test Interface.
+It mainly focuses on exporting information gathered during test run
+into JSON output files.
+
+### Output Structure
+
+UTI outputs come in filesystem tree structure (single tree), where directories
+correspond to suite levels and files correspond to suite setup, suite teardown
+or any test case at this level of suite.
+The directory name comes from SUITE_NAME Robot variable (the last part
+as the previous parts are higher level suites), converted to lowercase.
+If the suite name contains spaces (Robot converts underscores to spaces),
+they are replaced with underscores.
+
+The filesystem tree is rooted under tests/ (as suites in git are there),
+and for each component (test case, suite setup, suite teardown).
+
+Although we expect only ASCII text in the exported files,
+we manipulate files using UTF-8 encoding,
+so if Robot Framework uses a non-ascii character, it will be handled.
+
+### JSON schemas
+
+CSIT model is formally defined as a collection of JSON schema documents,
+one for each output file type.
+
+The current version specifies only one output file type:
+Info output for test case.
+
+The authoritative JSON schema documents are in JSON format.
+Git repository also contains YAML formatted document and conversion utility,
+which simplifies maintaining of the JSON document
+(no need to track brackets and commas), but are not authoritative.