chore: Enforce import types

.eslintrc

@@ -25,6 +25,9 @@
     "require-await": "off",
     "@typescript-eslint/require-await": "error",
     "@typescript-eslint/naming-convention": "error",
+    "import/no-cycle": "error",
+    "import/no-self-import": "error",
+    "@typescript-eslint/consistent-type-imports": "error",
     "import/order": [
       2,
       {

src/grpc/plugin.ts

@@ -1,7 +1,7 @@
 import { pluginV3 } from '@cloudquery/plugin-pb-javascript';
 import grpc = require('@grpc/grpc-js');
 
-import { Plugin } from '../plugin/plugin.js';
+import type { Plugin } from '../plugin/plugin.js';
 import { encodeTables, flattenTables } from '../schema/table.js';
 
 export class MigrateTable extends pluginV3.cloudquery.plugin.v3.Sync.MessageMigrateTable {}

src/grpc/server.ts

@@ -1,8 +1,8 @@
 import { pluginV3, discovery1 } from '@cloudquery/plugin-pb-javascript';
 import grpc = require('@grpc/grpc-js');
-import winston from 'winston';
+import type winston from 'winston';
 
-import { Plugin } from '../plugin/plugin.js';
+import type { Plugin } from '../plugin/plugin.js';
 
 import { DiscoveryServer } from './discovery.js';
 import { PluginServer } from './plugin.js';

src/memdb/delete-stale.ts

@@ -1,4 +1,4 @@
-import { DeleteStale } from '../grpc/plugin.js';
+import type { DeleteStale } from '../grpc/plugin.js';
 
 export type DeleteStaleFunction = (message: DeleteStale) => void;
 

src/memdb/memdb.ts

@@ -1,8 +1,10 @@
 import { default as Ajv } from 'ajv';
 
-import { Plugin, newPlugin, SyncOptions, TableOptions, NewClientFunction } from '../plugin/plugin.js';
+import type { Plugin, SyncOptions, TableOptions, NewClientFunction } from '../plugin/plugin.js';
+import { newPlugin } from '../plugin/plugin.js';
 import { sync } from '../scheduler/scheduler.js';
-import { Table, filterTables } from '../schema/table.js';
+import type { Table } from '../schema/table.js';
+import { filterTables } from '../schema/table.js';
 
 import { createDeleteStale } from './delete-stale.js';
 import { createOverwrite } from './overwrite.js';

src/memdb/overwrite.ts

@@ -1,6 +1,6 @@
-import { StructRowProxy } from '@apache-arrow/esnext-esm';
+import type { StructRowProxy } from '@apache-arrow/esnext-esm';
 
-import { Table } from '../schema/table.js';
+import type { Table } from '../schema/table.js';
 
 //eslint-disable-next-line @typescript-eslint/no-explicit-any
 export type OverwriteFunction = (table: Table, primaryKeys: string[], record: StructRowProxy<any>) => void;

src/memdb/read.ts

@@ -1,4 +1,4 @@
-import { ReadStream, ReadRequest } from '../grpc/plugin.js';
+import type { ReadStream, ReadRequest } from '../grpc/plugin.js';
 import { decodeTable } from '../schema/table.js';
 
 //eslint-disable-next-line @typescript-eslint/no-explicit-any

src/memdb/write.ts

@@ -1,8 +1,9 @@
-import { WriteStream, WriteRequest } from '../grpc/plugin.js';
-import { Table, decodeTable, decodeRecord, getPrimaryKeys } from '../schema/table.js';
+import type { WriteStream, WriteRequest } from '../grpc/plugin.js';
+import type { Table } from '../schema/table.js';
+import { decodeTable, decodeRecord, getPrimaryKeys } from '../schema/table.js';
 
-import { DeleteStaleFunction } from './delete-stale.js';
-import { OverwriteFunction } from './overwrite.js';
+import type { DeleteStaleFunction } from './delete-stale.js';
+import type { OverwriteFunction } from './overwrite.js';
 
 export const createWrite = (
   //eslint-disable-next-line @typescript-eslint/no-explicit-any

src/plugin/plugin.ts

@@ -1,7 +1,7 @@
-import { Logger } from 'winston';
+import type { Logger } from 'winston';
 
-import { SyncStream, ReadStream, WriteStream } from '../grpc/plugin.js';
-import { Table } from '../schema/table.js';
+import type { SyncStream, ReadStream, WriteStream } from '../grpc/plugin.js';
+import type { Table } from '../schema/table.js';
 
 export type BackendOptions = {
   tableName: string;

src/plugin/serve.test.ts

@@ -2,7 +2,8 @@ import test from 'ava';
 
 import { newMemDBPlugin } from '../memdb/memdb.js';
 
-import { createServeCommand, ServeArguments } from './serve.js';
+import type { ServeArguments } from './serve.js';
+import { createServeCommand } from './serve.js';
 
 const serve = createServeCommand(newMemDBPlugin()).exitProcess(false);
 

src/plugin/serve.ts

@@ -4,7 +4,7 @@ import { hideBin } from 'yargs/helpers';
 import { startServer, Network } from '../grpc/server.js';
 import { LogFormat, LogLevel, createLogger } from '../logger/logger.js';
 
-import { Plugin } from './plugin.js';
+import type { Plugin } from './plugin.js';
 
 const TELEMETRY_LEVEL_CHOICES = ['none', 'errors', 'stats', 'all'] as const;
 

src/scalar/bool.ts

@@ -1,7 +1,7 @@
 import { Bool as ArrowBool } from '@apache-arrow/esnext-esm';
 import { boolean, isBooleanable } from 'boolean';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Bool implements Scalar<boolean> {

src/scalar/date.ts

@@ -1,7 +1,8 @@
-import { DataType, Date_ as ArrowDate, DateUnit } from '@apache-arrow/esnext-esm';
+import type { DataType, DateUnit } from '@apache-arrow/esnext-esm';
+import { Date_ as ArrowDate } from '@apache-arrow/esnext-esm';
 import { DateTime } from 'luxon';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Date implements Scalar<DateTime> {

src/scalar/float32.ts

@@ -1,6 +1,7 @@
-import { DataType, Float32 as ArrowFloat32 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Float32 as ArrowFloat32 } from '@apache-arrow/esnext-esm';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Float32 implements Scalar<number> {

src/scalar/float64.ts

@@ -1,6 +1,7 @@
-import { DataType, Float64 as ArrowFloat64 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Float64 as ArrowFloat64 } from '@apache-arrow/esnext-esm';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Float64 implements Scalar<number> {

src/scalar/int16.ts

@@ -1,7 +1,8 @@
-import { DataType, Int16 as ArrowInt16 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Int16 as ArrowInt16 } from '@apache-arrow/esnext-esm';
 import { bigIntToNumber } from '@apache-arrow/esnext-esm/util/bigint.js';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Int16 implements Scalar<bigint> {

src/scalar/int32.ts

@@ -1,7 +1,8 @@
-import { DataType, Int32 as ArrowInt32 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Int32 as ArrowInt32 } from '@apache-arrow/esnext-esm';
 import { bigIntToNumber } from '@apache-arrow/esnext-esm/util/bigint.js';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Int32 implements Scalar<bigint> {

src/scalar/int64.ts

@@ -1,7 +1,8 @@
-import { DataType, Int64 as ArrowInt64 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Int64 as ArrowInt64 } from '@apache-arrow/esnext-esm';
 import { bigIntToNumber } from '@apache-arrow/esnext-esm/util/bigint.js';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Int64 implements Scalar<bigint> {

src/scalar/json.ts

@@ -1,8 +1,8 @@
 import { Utf8 as ArrowString } from '@apache-arrow/esnext-esm';
 
-import { Nullable } from '../schema/types.js';
+import type { Nullable } from '../schema/types.js';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 const validate = (value: string) => {

src/scalar/list.ts

@@ -1,6 +1,7 @@
-import { DataType, List as ArrowList } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { List as ArrowList } from '@apache-arrow/esnext-esm';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 type TVector<T extends Scalar<unknown>> = T[];

src/scalar/text.ts

@@ -1,6 +1,6 @@
 import { Utf8 as ArrowString } from '@apache-arrow/esnext-esm';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Text implements Scalar<string> {

src/scalar/timestamp.ts

@@ -1,7 +1,8 @@
-import { DataType, Timestamp as ArrowTimestamp, TimeUnit } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Timestamp as ArrowTimestamp, TimeUnit } from '@apache-arrow/esnext-esm';
 import { DateTime } from 'luxon';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Timestamp implements Scalar<DateTime> {

src/scalar/uint16.ts

@@ -1,7 +1,8 @@
-import { DataType, Uint16 as ArrowUint16 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Uint16 as ArrowUint16 } from '@apache-arrow/esnext-esm';
 import { bigIntToNumber } from '@apache-arrow/esnext-esm/util/bigint.js';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Uint16 implements Scalar<bigint> {

src/scalar/uint32.ts

@@ -1,7 +1,8 @@
-import { DataType, Uint32 as ArrowUint32 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Uint32 as ArrowUint32 } from '@apache-arrow/esnext-esm';
 import { bigIntToNumber } from '@apache-arrow/esnext-esm/util/bigint.js';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Uint32 implements Scalar<bigint> {

src/scalar/uint64.ts

@@ -1,7 +1,8 @@
-import { DataType, Uint64 as ArrowUint64 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Uint64 as ArrowUint64 } from '@apache-arrow/esnext-esm';
 import { bigIntToNumber } from '@apache-arrow/esnext-esm/util/bigint.js';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class Uint64 implements Scalar<bigint> {

src/scalar/uuid.ts

@@ -1,9 +1,9 @@
 import { FixedSizeBinary } from '@apache-arrow/esnext-esm';
 import { parse, stringify } from 'uuid';
 
-import { Nullable } from '../schema/types.js';
+import type { Nullable } from '../schema/types.js';
 
-import { Scalar } from './scalar.js';
+import type { Scalar } from './scalar.js';
 import { isInvalid, NULL_VALUE } from './util.js';
 
 export class UUID implements Scalar<Nullable<Uint8Array>> {

src/scheduler/cqid.ts

@@ -3,7 +3,7 @@ import { createHash } from 'node:crypto';
 import { v4 as uuidv4, v5 as uuidv5, NIL as NIL_UUID } from 'uuid';
 
 import { cqIDColumn } from '../schema/meta.js';
-import { Resource } from '../schema/resource.js';
+import type { Resource } from '../schema/resource.js';
 import { getPrimaryKeys } from '../schema/table.js';
 
 export const setCQId = (resource: Resource, deterministicCQId: boolean, generator: () => string = uuidv4) => {

src/scheduler/scheduler.ts

@@ -2,14 +2,16 @@ import { Duplex } from 'node:stream';
 
 import pMap from 'p-map';
 import pTimeout from 'p-timeout';
-import { Logger } from 'winston';
+import type { Logger } from 'winston';
 
-import { SyncStream, SyncResponse, MigrateTable, Insert } from '../grpc/plugin.js';
-import { Column } from '../schema/column.js';
-import { ClientMeta } from '../schema/meta.js';
+import type { SyncStream } from '../grpc/plugin.js';
+import { SyncResponse, MigrateTable, Insert } from '../grpc/plugin.js';
+import type { Column } from '../schema/column.js';
+import type { ClientMeta } from '../schema/meta.js';
 import { Resource, encodeResource } from '../schema/resource.js';
-import { Table, encodeTable, flattenTables } from '../schema/table.js';
-import { Nullable } from '../schema/types.js';
+import type { Table } from '../schema/table.js';
+import { encodeTable, flattenTables } from '../schema/table.js';
+import type { Nullable } from '../schema/types.js';
 
 import { setCQId } from './cqid.js';
 

src/schema/column.ts

@@ -1,12 +1,14 @@
 import { isDeepStrictEqual } from 'node:util';
 
-import { DataType, Field, Utf8 } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Field, Utf8 } from '@apache-arrow/esnext-esm';
 
-import { ExtensionType, isExtensionType } from '../types/extensions.js';
+import type { ExtensionType } from '../types/extensions.js';
+import { isExtensionType } from '../types/extensions.js';
 
 import * as arrow from './arrow.js';
-import { ClientMeta } from './meta.js';
-import { Resource } from './resource.js';
+import type { ClientMeta } from './meta.js';
+import type { Resource } from './resource.js';
 
 export type ColumnResolver = (meta: ClientMeta, resource: Resource, c: Column) => Promise<void>;
 

src/schema/meta.ts

@@ -2,9 +2,11 @@ import { Utf8, TimeNanosecond } from '@apache-arrow/esnext-esm';
 
 import { UUIDType } from '../types/uuid.js';
 
-import { Column, createColumn, ColumnResolver } from './column.js';
-import { Resource } from './resource.js';
-import { Table, getPrimaryKeys } from './table.js';
+import type { Column, ColumnResolver } from './column.js';
+import { createColumn } from './column.js';
+import type { Resource } from './resource.js';
+import type { Table } from './table.js';
+import { getPrimaryKeys } from './table.js';
 
 export type ClientMeta = {
   id: () => string;

src/schema/resolvers.ts

@@ -1,6 +1,6 @@
 import { getProperty } from 'dot-prop';
 
-import { ColumnResolver } from './column.js';
+import type { ColumnResolver } from './column.js';
 
 export const pathResolver = (path: string): ColumnResolver => {
   return (_, resource, c) => {

src/schema/resource.ts

@@ -1,11 +1,13 @@
 import { tableToIPC, Table as ArrowTable, RecordBatch, vectorFromArray } from '@apache-arrow/esnext-esm';
 
-import { Scalar, Vector, newScalar } from '../scalar/scalar.js';
+import type { Scalar, Vector } from '../scalar/scalar.js';
+import { newScalar } from '../scalar/scalar.js';
 import { isExtensionType } from '../types/extensions.js';
 
 import { cqIDColumn } from './meta.js';
-import { Table, toArrowSchema } from './table.js';
-import { Nullable } from './types.js';
+import type { Table } from './table.js';
+import { toArrowSchema } from './table.js';
+import type { Nullable } from './types.js';
 
 export class Resource {
   item: unknown;

src/schema/table.ts

@@ -1,13 +1,15 @@
-import { Writable } from 'node:stream';
+import type { Writable } from 'node:stream';
 
-import { Table as ArrowTable, tableFromIPC, tableToIPC, Schema, RecordBatch } from '@apache-arrow/esnext-esm';
+import type { RecordBatch } from '@apache-arrow/esnext-esm';
+import { Table as ArrowTable, tableFromIPC, tableToIPC, Schema } from '@apache-arrow/esnext-esm';
 import { isMatch } from 'matcher';
 
 import * as arrow from './arrow.js';
-import { Column, fromArrowField, toArrowField } from './column.js';
-import { ClientMeta } from './meta.js';
-import { Resource } from './resource.js';
-import { Nullable } from './types.js';
+import type { Column } from './column.js';
+import { fromArrowField, toArrowField } from './column.js';
+import type { ClientMeta } from './meta.js';
+import type { Resource } from './resource.js';
+import type { Nullable } from './types.js';
 
 export type TableResolver = (clientMeta: ClientMeta, parent: Nullable<Resource>, stream: Writable) => Promise<void>;
 export type RowResolver = (clientMeta: ClientMeta, resource: Resource) => Promise<void>;

src/transformers/openapi.test.ts

@@ -1,7 +1,8 @@
 import { Utf8, Int64, Bool } from '@apache-arrow/esnext-esm';
 import test from 'ava';
 
-import { Column, createColumn } from '../schema/column.js';
+import type { Column } from '../schema/column.js';
+import { createColumn } from '../schema/column.js';
 import { JSONType } from '../types/json.js';
 
 import { oapiDefinitionToColumns } from './openapi.js';

src/transformers/openapi.ts

@@ -1,6 +1,8 @@
-import { DataType, Utf8, Int64, Bool } from '@apache-arrow/esnext-esm';
+import type { DataType } from '@apache-arrow/esnext-esm';
+import { Utf8, Int64, Bool } from '@apache-arrow/esnext-esm';
 
-import { Column, createColumn } from '../schema/column.js';
+import type { Column } from '../schema/column.js';
+import { createColumn } from '../schema/column.js';
 import { JSONType } from '../types/json.js';
 
 interface OAPIProperty {