Rebuild as a dialect-independent schema representation

.github/workflows/check-standard.yaml

@@ -29,7 +29,7 @@ jobs:
       R_KEEP_PKG_SOURCE: yes
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
       - uses: r-lib/actions/setup-pandoc@v2
 
@@ -41,9 +41,7 @@ jobs:
 
       - uses: r-lib/actions/setup-r-dependencies@v2
         with:
-          extra-packages: |
-            any::rcmdcheck
-            RConsortium/OOP-WG
+          extra-packages: any::rcmdcheck
           needs: check
 
       - uses: r-lib/actions/check-r-package@v2

DESCRIPTION

@@ -1,25 +1,40 @@
 Package: sqlr
-Title: Build SQL queries for creating/altering tables
-Version: 0.0.1.9000
+Title: Represent and Generate SQL Schemas
+Version: 0.0.0.9000
 Authors@R: c(
     person("Nicolas", "Bennett", email = "r@nbenn.ch", role = c("aut", "cre")))
 Description:
-    Starting with MardaDB/MySQL and possibly expanding to other SQL dialects, the aim of this package is to help with generating queries for creating and altering tables.
+    A dialect-independent representation of a relational schema -- tables,
+    columns, types, constraints and indexes -- that can be built up from R,
+    rendered as data definition language for a given SQL dialect, and learned
+    back from a live database. Dialect support is provided by companion
+    packages.
 Depends:
-    R (>= 3.6.0),
-    R7 (>= 0.0.0.9000)
+    R (>= 4.1)
 Imports:
-    DBI,
-    methods
+    S7,
+    utils
 Suggests:
-    testthat (>= 3.0.0),
-    RPostgres
+    testthat (>= 3.0.0)
 URL: https://github.com/nbenn/sqlr
 BugReports: https://github.com/nbenn/sqlr/issues
 License: MIT + file LICENSE
 Encoding: UTF-8
-LazyData: true
-RoxygenNote: 7.2.1
-Remotes:
-    RConsortium/OOP-WG
 Config/testthat/edition: 3
+Config/roxygen2/version: 8.1.0
+Collate:
+    'sqlr-package.R'
+    'class_sql.R'
+    'class_type.R'
+    'type_shorthand.R'
+    'class_column.R'
+    'class_constraint.R'
+    'class_index.R'
+    'class_table.R'
+    'class_schema.R'
+    'class_dialect.R'
+    'generics.R'
+    'registry.R'
+    'order.R'
+    'render.R'
+    'compare.R'

NAMESPACE

@@ -1,10 +1,58 @@
 # Generated by roxygen2: do not edit by hand
 
-export()
-export(int)
-export(parse_sql)
-export(render_sql)
-export(simulate_postgres)
-export(smallint)
-import(R7)
-importFrom(DBI,SQL)
+export(as_sqlr_type)
+export(sqlr_bigint)
+export(sqlr_binary_type)
+export(sqlr_blob)
+export(sqlr_boolean)
+export(sqlr_boolean_type)
+export(sqlr_catalog)
+export(sqlr_char)
+export(sqlr_check)
+export(sqlr_column)
+export(sqlr_constraint)
+export(sqlr_date)
+export(sqlr_decimal_type)
+export(sqlr_defers_constraints)
+export(sqlr_dialect)
+export(sqlr_diff)
+export(sqlr_double)
+export(sqlr_equal)
+export(sqlr_float_type)
+export(sqlr_for)
+export(sqlr_foreign_key)
+export(sqlr_identity)
+export(sqlr_index)
+export(sqlr_index_spec)
+export(sqlr_int)
+export(sqlr_integer_type)
+export(sqlr_json)
+export(sqlr_json_type)
+export(sqlr_numeric)
+export(sqlr_other)
+export(sqlr_other_type)
+export(sqlr_parse_type)
+export(sqlr_primary_key)
+export(sqlr_quote)
+export(sqlr_quote_literal)
+export(sqlr_real)
+export(sqlr_reflect)
+export(sqlr_reflect_schema)
+export(sqlr_register_dialect)
+export(sqlr_render)
+export(sqlr_render_type)
+export(sqlr_schema)
+export(sqlr_smallint)
+export(sqlr_sql)
+export(sqlr_string_type)
+export(sqlr_table)
+export(sqlr_text)
+export(sqlr_time)
+export(sqlr_time_type)
+export(sqlr_timestamp)
+export(sqlr_type)
+export(sqlr_unique)
+export(sqlr_uuid)
+export(sqlr_uuid_type)
+export(sqlr_varchar)
+import(S7)

R/class_column.R

@@ -0,0 +1,83 @@
+#' Table columns
+#'
+#' A column of a [sqlr_table()]. `identity` describes an automatically
+#' generated key; it is what a dialect maps its `SERIAL`-style spellings onto.
+#'
+#' @param name Column name.
+#' @param type A [sqlr_type], or a string parsed by [as_sqlr_type()].
+#' @param null Whether the column admits `NULL`. A column named in a primary
+#'   key is forced to `FALSE`, matching what every engine reports back.
+#' @param default Default value: a length-one atomic, a [sqlr_sql()]
+#'   expression, or `NULL` for none.
+#' @param description Comment attached to the column.
+#' @param identity An [sqlr_identity()], or `NULL`.
+#' @param attrs Named list of dialect-specific attributes, ignored by dialects
+#'   that do not recognise them.
+#' @param generated Whether the identity always applies, or yields to a
+#'   supplied value.
+#' @param start,increment Sequence start and step.
+#'
+#' @return A `sqlr_column` or `sqlr_identity` object.
+#'
+#' @examples
+#' sqlr_column("email", "varchar(255)", null = FALSE)
+#' sqlr_column("id", sqlr_bigint(), identity = sqlr_identity())
+#'
+#' @export
+sqlr_identity <- new_class(
+  "sqlr_identity",
+  properties = list(
+    generated = new_property(class_character, default = "by default"),
+    start = new_property(class_integer, default = 1L),
+    increment = new_property(class_integer, default = 1L)
+  ),
+  validator = function(self) {
+    if (!self@generated %in% c("always", "by default")) {
+      "`generated` must be \"always\" or \"by default\""
+    }
+  }
+)
+
+#' @rdname sqlr_identity
+#' @export
+sqlr_column <- new_class(
+  "sqlr_column",
+  properties = list(
+    name = class_character,
+    type = sqlr_type,
+    null = new_property(class_logical, default = TRUE),
+    default = new_property(class_any, default = NULL),
+    description = new_property(class_character, default = NA_character_),
+    identity = new_property(new_union(NULL, sqlr_identity), default = NULL),
+    attrs = new_property(class_list, default = quote(list()))
+  ),
+  constructor = function(name, type, null = TRUE, default = NULL,
+                         description = NA_character_, identity = NULL,
+                         attrs = list()) {
+    new_object(
+      S7_object(),
+      name = name,
+      type = as_sqlr_type(type),
+      null = null,
+      default = default,
+      description = description,
+      identity = identity,
+      attrs = attrs
+    )
+  },
+  validator = function(self) {
+    if (length(self@name) != 1L || is.na(self@name)) {
+      return("`name` must be a string")
+    }
+    if (length(self@null) != 1L || is.na(self@null)) {
+      return("`null` must be TRUE or FALSE")
+    }
+    if (!valid_default(self@default)) {
+      "`default` must be NULL, a length-one atomic, or a sqlr_sql()"
+    }
+  }
+)
+
+valid_default <- function(x) {
+  is.null(x) || S7_inherits(x, sqlr_sql) || (is.atomic(x) && length(x) == 1L)
+}