v2 migration guides (#138)

* Adds migration guide hbs files

* Adds another line of txt

* Adds migration files

* Improves indentation

* Adds subheadings

* Updates Api Access By Tags and Paths Updated

* reason and action updated

* Updates 200 migration guide

* Adds new section to migration guide

* Samples generated

Author: spacether

modules/openapi-json-schema-generator/src/main/java/org/openapijsonschematools/codegen/languages/PythonClientCodegen.java

@@ -602,6 +602,8 @@ public void processOpts() {
             readmeTemplate = "README_onlypackage.hbs";
         }
         supportingFiles.add(new SupportingFile(readmeTemplate, "", readmePath));
+        supportingFiles.add(new SupportingFile("migration_2_0_0.hbs", "", "migration_2_0_0.md"));
+        supportingFiles.add(new SupportingFile("migration_other_python_generators.hbs", "", "migration_other_python_generators.md"));
         supportingFiles.add(new SupportingFile("__init__package.hbs", packagePath(), "__init__.py"));
 
         if (!generateSourceCodeOnly) {

modules/openapi-json-schema-generator/src/main/resources/python/README.hbs

@@ -19,94 +19,9 @@ For more information, please visit [{{{infoUrl}}}]({{{infoUrl}}})
 
 Python {{generatorLanguageVersion}}
 
-## Migration from other generators like python and python-legacy
-
-### Changes
-1. This generator uses spec case for all (object) property names and parameter names.
-    - So if the spec has a property name like camelCase, it will use camelCase rather than camel_case
-    - So you will need to update how you input and read properties to use spec case
-2. Endpoint parameters are stored in dictionaries to prevent collisions (explanation below)
-    - So you will need to update how you pass data in to endpoints
-3. Endpoint responses now include the original response, the deserialized response body, and (todo)the deserialized headers
-    - So you will need to update your code to use response.body to access deserialized data
-4. All validated data is instantiated in an instance that subclasses all validated Schema classes and Decimal/str/tuple/frozendict/NoneClass/BoolClass/bytes/io.FileIO
-    - This means that you can use isinstance to check if a payload validated against a schema class
-    - This means that no data will be of type None/True/False
-        - ingested None will subclass NoneClass
-        - ingested True will subclass BoolClass
-        - ingested False will subclass BoolClass
-        - So if you need to check is True/False/None, instead use instance.is_true_()/.is_false_()/.is_none_()
-5. All validated class instances are immutable except for ones based on io.File
-    - This is because if properties were changed after validation, that validation would no longer apply
-    - So no changing values or property values after a class has been instantiated
-6. String + Number types with formats
-    - String type data is stored as a string and if you need to access types based on its format like date,
-    date-time, uuid, number etc then you will need to use accessor functions on the instance
-    - type string + format: See .as_date_, .as_datetime_, .as_decimal_, .as_uuid_
-    - type number + format: See .as_float_, .as_int_
-    - this was done because openapi/json-schema defines constraints. string data may be type string with no format
-    keyword in one schema, and include a format constraint in another schema
-    - So if you need to access a string format based type, use as_date_/as_datetime_/as_decimal_/as_uuid_
-    - So if you need to access a number format based type, use as_int_/as_float_
-7. Property access on AnyType(type unset) or object(dict) schemas
-    - Only required keys with valid python names are properties like .someProp and have type hints
-    - All optional keys may not exist, so properties are not defined for them
-    - One can access optional values with dict_instance['optionalProp'] and KeyError will be raised if it does not exist
-    - Use get_item_ if you need a way to always get a value whether or not the key exists
-        - If the key does not exist, schemas.unset is returned from calling dict_instance.get_item_('optionalProp')
-        - All required and optional keys have type hints for this method, and @typing.overload is used
-        - A type hint is also generated for additionalProperties accessed using this method
-    - So you will need to update you code to use some_instance['optionalProp'] to access optional property
-    and additionalProperty values
-8. The location of the api classes has changed
-    - Api classes are located in your_package.apis.tags.some_api
-    - This change was made to eliminate redundant code generation
-    - Legacy generators generated the same endpoint twice if it had > 1 tag on it
-    - This generator defines an endpoint in one class, then inherits that class to generate
-      apis by tags and by paths
-    - This change reduces code and allows quicker run time if you use the path apis
-        - path apis are at your_package.apis.paths.some_path
-    - Those apis will only load their needed models, which is less to load than all of the resources needed in a tag api
-    - So you will need to update your import paths to the api classes
-
-### Why are Leading and Trailing Underscores in class and method names?
-Classes can have arbitrarily named properties set on them
-Endpoints can have arbitrary operationId method names set
-For those reasons, I use the prefix and suffix _ to greatly reduce the likelihood of collisions
-on protected + public classes/methods.
-
-### Object property spec case
-This was done because when payloads are ingested, they can be validated against N number of schemas.
-If the input signature used a different property name then that has mutated the payload.
-So SchemaA and SchemaB must both see the camelCase spec named variable.
-Also it is possible to send in two properties, named camelCase and camel_case in the same payload.
-That use case should work, so spec case is used.
-
-### Parameter spec case
-Parameters can be included in different locations including:
-- query
-- path
-- header
-- cookie
-
-Any of those parameters could use the same parameter names, so if every parameter
-was included as an endpoint parameter in a function signature, they would collide.
-For that reason, each of those inputs have been separated out into separate typed dictionaries:
-- query_params
-- path_params
-- header_params
-- cookie_params
-
-So when updating your code, you will need to pass endpoint parameters in using those
-dictionaries.
-
-### Endpoint responses
-Endpoint responses have been enriched to now include more information.
-Any response reom an endpoint will now include the following properties:
-response: urllib3.HTTPResponse
-body: typing.Union[Unset, Schema]
-headers: typing.Union[Unset, TODO]
-Note: response header deserialization has not yet been added
+## Migration Guides
+- [2.0.0 Migration Guide](migration_2_0_0.md)
+- [Migration from Other Python Generators](migration_other_python_generators.md)
 
 
 ## Installation & Usage

modules/openapi-json-schema-generator/src/main/resources/python/migration_2_0_0.hbs

@@ -0,0 +1,203 @@
+# Migration v1.X.X to v2.0.0
+
+- [Compatibility note for opeanpi-generator](#compatibility-note-for-opeanpi-generator)
+- [Component Generation](#component-generation)
+- [Packaging Changes](#packaging-changes)
+- [Path Generation](#path-generation)
+- [Configuration Info Refactored](#configuration-info-refactored)
+- [Servers and Security Generation](#servers-and-security-generation)
+- [Java Classes for Openapi Data Refactored](#java-classes-for-openapi-data-refactored)
+- [Api Access by Tags and Paths Updated](#api-access-by-tags-and-paths-updated)
+- [Some Method/Property/Input/Class Names Updated](#some-methodpropertyinputclass-names-updated)
+- [Documentation Updated](#documentation-updated)
+
+## Compatibility note for opeanpi-generator
+The v1.0.4 release is nearly identical to the openapi-generator v6.3.0 release
+
+Below is a summary of big changes when updating you code from v1.X.X to 2.0.0
+
+## Component Generation
+Update:
+Openapi document components in "#/components/x" are now generated in a components/x packages
+Ths applies to:
+- headers
+- parameters
+- request_bodies
+- responses
+- schemas
+- security_schemes
+
+The generator now writes a class for each of those generated components.
+
+### Reason
+A lot of openapi data is $ref references throughout an openapi document.
+With this update, those $ref source locations are generated with file system paths that closely mirror the openapi
+document json schema path to that info. $ref definition is then imported in generated python code.
+This minimizes the amount of code that is generated, imposes well defined encapsulation and allows templates to be
+re-used for many types of data regardless of where the data is in the source openapi document.
+
+### Action
+- Update where you are importing models from, models are now component schemas
+  - File path change: model/pet.py -> components/schema/pet.py
+
+## Packaging changes
+Code has been updated to use .toml packaging. Code is now distributed in a src directory
+
+### Reason
+These updates follow latest python packaging best practices
+
+### Action
+- if you are suppressing generation of any files, you will need to edit those file paths
+  - File Path Change: package_name -> src/package_name
+
+## Path Generation
+If paths contain inline descriptions of parameters, request bodies, responses, security, or servers,
+then those are now generated in separate files. Those files are imported into the endpoint code.
+File locations closely mirror the openapi data json schema path.
+
+### Reason
+Generating those files in paths that closely mirror the json schema paths will allow
+the generator to use $ref to any location in the openapi document in the future, not just components.
+These could include:
+- relative $refs
+- a request body $ref referring to the request body in another endpoint
+
+This also allowed the generation code to work the same way regardless of where the header/requestBody etc
+is in the source spec.
+
+Note:
+Operations are now at
+paths/somePath/get/operation.py
+and not at
+paths/somePath/get/__init__.py
+to minimize the amount of memory needed when importing the python package.
+The configurations.api_configuration.py file imports all servers defined at:
+- openapi document root
+- pathItem
+- pathItem operation
+And if servers were defined in pathItem operations, then every operation that contains a server would be imported
+in api_configuration.py. Which could be many many files.
+
+So instead
+- operation endpoint definition was moved to paths/somePath/get/operation.py
+- paths/somePath/get/__init__.py stays empty and does not need lots of memory when api_configuration.py imports servers
+- server information was kept in paths/somePath/get/servers/server_x.py
+
+### Action
+- if you are importing any endpoint form its file, update your import
+  - File path update: paths/somePath/get.py -> paths/somePath/get/operation.py
+
+## Configuration Info Refactored
+Configuration information was separated into two classes
+- configurations/api_configuration.py ApiConfiguration for:
+  - server info
+  - security (auth) info
+  - logging info
+- configurations/schema_configuration.py SchemaConfiguration for:
+  - disabled openapi/json-schema keywords
+
+### Reason
+Schema validation only relies on SchemaConfiguration data and does not need to know about any ApiConfiguration info
+General api configuration info was poorly structured in the legacy configuration class which had 13 inputs.
+The refactored ApiConfiguration now has 4 inputs which define servers and security info.
+Having these separate classes prevents circular imports when the schemas.py file imports its SchemaConfiguration class.
+
+### Action
+- When you instantiate ApiClient, update your code to pass in an instance of SchemaConfiguration + ApiConfiguration
+
+
+## Servers and Security Generation
+Servers are now generated as separate files with one class per file wherever they were defined in the openapi document
+- servers/server_0.py
+- paths/somePath/servers/server_0.py
+- paths/somePath/get/servers/server_0.py
+Security requirements objects are now generated as separate files with one security requirement object per file
+wherever they were defined in the openapi document
+- security/security_requirement_object_0.py
+- paths/somePath/get/security/security_requirement_object_0.py
+
+### Reason
+Server classes now re-use schema validation code to ensure that inputs to server variables are valid.
+Generating these separate files minimizes generated code and maximizes code re-use.
+
+### Action
+- If endpoints need to use specific servers or security not at index 0, pass security_index_info + server_index_info
+  into ApiConfiguration when instantiating it
+- If you use non-default server variable values, then update your code to pass in server_info into ApiConfiguration
+
+## Java Classes for Openapi Data Refactored
+Almost every java class used to store openapi document data at generation time has been re-written or refactored.
+The new classes are much shorter and contain only what is needed to generate code and documentation.
+This will make it much easier to add new openapi v3.1.0 features like new json schema keywords.
+Generator interface methods were also refactored to simplify Java model instantiation and code generation.
+Almost all properties are now public static final and are:
+- immutable
+- publicly accessible to the templates
+
+### Reason
+These updates make the code much more maintainable.
+The number of properties that have to be maintained is much smaller
+- Component Schema: ~100 properties in CodegenModel.java -> ~50 properties in CodegenSchema.java
+- PathItem Operation: ~75 properties CodegenOperation: ~25 properties
+
+This will reduce bugs like: why can't I access this property in this template
+Because instances are mostly immutable it is very clear where the wrong value is being created/assigned.
+
+### Action
+- if you are customizing the python generator, you will need to update your java code
+
+## Api Access By Tags and Paths Updated
+Previously, keys togo from tags and paths to apis were enums.
+The code was updated to use a TypedDict and uses strings as the keys.
+
+### Reason
+Making this change allows type hinting to work for the TypedDict with string keys
+
+### Action
+- If you use path_to_api.py or tag_to_api.py, update the key that you use to access the api
+
+## Some Method/Property/Input/Class Names Updated
+- is_true_oapg -> is_true_
+- is_false_oapg -> is_false_
+- is_none_oapg -> is_none_
+- as_date_oapg -> as_date_
+- as_datetime_oapg -> as_datetime_
+- as_decimal_oapg -> as_decimal_
+- as_uuid_oapg -> as_uuid_
+- as_float_oapg -> as_float_
+- as_int_oapg -> as_int_
+- get_item_oapg -> get_item_
+- from_openapi_data_oapg -> from_openapi_data_
+- _verify_typed_dict_inputs_oapg -> _verify_typed_dict_inputs
+- _configuration -> configuration_
+- _arg -> arg_
+- _args -> args_
+- MetaOapg -> Schema_
+- JsonSchema -> OpenApiSchema
+
+### Reason
+Classes can have arbitrarily named properties set on them
+Endpoints can have arbitrary operationId method names set
+For those reasons, I use the prefix and suffix _ to greatly reduce the likelihood of collisions
+on protected + public classes/methods.
+
+### Action
+- if you use the above methods/inputs/properties/classes update them to the latest names
+
+## Documentation Updated
+- components now have sections in the readme
+  - models became component schemas
+- one file is now generated for each endpoint
+  - that file now has a table of contents
+  - heading indentation levels now are indented correctly in descending order
+  - endpoint now includes server and security info (if security exists)
+- servers section added to readme if servers were defined in the openapi document root
+- security section added to readme if security was defined in the openapi document root
+
+### Reason
+Endpoint documentation had indentation and linking bugs before, this fixes them.
+When all endpoints docs were written in one file it was difficult to link ot the correct section.
+How to set server and security info was unclear before, the new docs and classes should clarify that.
+
+### Action
+- if you link to specific parts of the documentation, update your links