Retrieve schema (Back-end service)

[stefjoosten]

At runtime, we want every generated application to know its own schema, so the migration algorithm can retrieve the correct schema by simply asking the system. A schema is the Ampersand-script without the INTERFACEs and without the population. For this purpose, the Ampersand compiler must place a copy of the schema in the generated back-end application.

This issue is part of the Migration epic, which facilitates incremental development of the Ampersand application in production.

Task

Make een back-end service ``retrieve schema’’, which yields the original Ampersand schema of the deployed web application without the interfaces and without the population.

[hanjoosten]

Please elaborate on what info is missing in the current. Json files, and how you think this info should be used. Op ma 1 mei 2023 07:36 schreef Stef Joosten ***@***.***>:

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At runtime, we want every generated application to know its own schema. A schema is the Ampersand-script without the INTERFACEs and without the population. For this purpose, the Ampersand compiler must place a copy in the generated back-end application. This issue is part of the Migration epic, which facilitates incremental development of Ampersand application in production. Task Make een back-end service ``retrieve schema’’, which yields the original Ampersand script of the deployed web application without the interfaces and without the population. — Reply to this email directly, view it on GitHub <#111>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAI3D6BME4JI2CTDBZ56DPDXD5DWLANCNFSM6AAAAAAXROJONU> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[stefjoosten]

Choice

With every migration, we store the schema in Ampersand source format in the back end. The compiler can question the back end to retrieve the actual schema of the running application.

We can realize a first implementation by enhancing the ampersand export command.

Complication

An Ampersand application consisting of multiple namespaces may cause complications. We need to investigate that. For now, we'll implement the export while expanding the aliases in namespaces, so that a combination of files can be exported in one file.