[WIP, lib v19] Source generators for Types and Requests with System.Text.Json support

[vova-lantsov-dev]

Summary

This PR introduces 2 source generators that generate the classes for Types and Requests folders. Also it brings an API parser app.

API parser

It produces a JSON file according to the following schema: https://github.com/TelegramBots/Telegram.Bot/blob/abdab6f0fdc5dcf9e84364dfc431abce766ddcf4/src/Telegram.Bot.ApiParser/schema.json

Types source generator

Scriban template that will be rendered for each Bot API type: https://github.com/TelegramBots/Telegram.Bot/blob/abdab6f0fdc5dcf9e84364dfc431abce766ddcf4/src/Telegram.Bot.Generators/Templates.Types.cs#L16-L69

where:

• {{ type_namespace }} is namespace (starts with Telegram.Bot.Types but can additionally contain sub-namespace such as Telegram.Bot.Types.InlineQueryResults)
• {{ type_description }} is type's multi-line description parsed from official Bot API page
• {{ type_name }} is the class'es name, for example for Bot API type Chat we will generate Chat class located in file Chat.generated.cs
• {{ parameter.parameter_description }} is property (parameter) multi-line description parsed from official Bot API page
• {{ parameter.parameter_name }} is snake_case name of parameter parsed from official Bot API page
• {{ parameter_type_name }} is fully qualified type name of property, including its namespace (if needed)
• {{ pascal_case_name }} is property name in PascalCase

The main concepts of this generation are:

• JsonIgnore attribute as well as Newtonsoft's Required and DefaultValueHandling arguments are only added when necessary
• Generated classes are partial so they can be extended with custom logic
• If class with corresponding name already exist and IS NOT partial - we skip generation of such class. If it exists and IS partial - class will be generated.

At the moment, the source generator looks for class types with public and without static modifiers, located inside Types folder and all sub-folders.

TODO

• [x] Add support for Required and Ignore attributes/arguments
• [ ] Extend new Enum source generator with STJ serializers
• [ ] Allow sub-namespaces for some types (such as Telegram.Bot.Types.InlineQueryResults)
• [x] Add support for custom mapping of type names (f.e. ForceReply -> ForceReplyMarkup)
• [ ] Write unit tests

Requests source generator

TODO

[vova-lantsov-dev]

@tuscen @karb0f0s @MihaZupan let's discuss this feature if we can bring it in 18.0.0 release

[Lorymi]

Any update?

[tuscen]

Unfortunately, I don’t have enough free time at the moment to review and test this PR.