Bindgen: Generate spec schema if missing

CHANGELOG.md

@@ -18,6 +18,7 @@
 
 ### Internals
 * Follow on to ([PR #7300](https://github.com/realm/realm-core/pull/7300)) to allow SDKs to construct a fake user for testing SyncManager::get_user -> App::create_fake_user_for_testing ([PR #7632](https://github.com/realm/realm-core/pull/7632))
+* Bindgen: Generating spec schema if missing. ([PR #7636](https://github.com/realm/realm-core/pull/7636))
 
 ----------------------------------------------
 

bindgen/CMakeLists.txt

@@ -16,7 +16,7 @@ set(SCHEMA_FILE ${CMAKE_CURRENT_SOURCE_DIR}/generated/spec.schema.json)
 add_custom_command(
     OUTPUT ${SCHEMA_FILE}
     WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
-    COMMAND ${NPX} typescript-json-schema ${CMAKE_CURRENT_SOURCE_DIR}/tsconfig.json RelaxedSpec --include ${CMAKE_CURRENT_SOURCE_DIR}/src/spec/relaxed-model.ts --out ${SCHEMA_FILE} --required --noExtraProps --aliasRefs
+    COMMAND ${NPX} tsx -- "${CMAKE_CURRENT_FUNCTION_LIST_DIR}/realm-bindgen.ts" generate-schema
     VERBATIM
     MAIN_DEPENDENCY src/spec/relaxed-model.ts
     DEPENDS
@@ -48,12 +48,6 @@ function(bindgen)
         endif()
     endforeach()
 
-    # Don't want to set cmake_minimum_required() here because it has other effects and needs to be done early.
-    # Remove this once https://github.com/realm/realm-core/issues/6537 bumps realm-core's minimum.
-    if(NOT CMAKE_CURRENT_FUNCTION_LIST_DIR)
-        message(FATAL_ERROR "bindgen() requires cmake 3.17+")
-    endif()
-
     get_property(BINDGEN_LIB_TS_FILES TARGET BindgenSpecJsonSchema PROPERTY BINDGEN_LIB_TS_FILES)
     get_property(NPX TARGET BindgenSpecJsonSchema PROPERTY NPX)
 
@@ -62,7 +56,7 @@ function(bindgen)
     add_custom_command(
         OUTPUT ${BINDGEN_OUTPUTS}
         WORKING_DIRECTORY ${CMAKE_CURRENT_FUNCTION_LIST_DIR}
-        COMMAND ${NPX} tsx -- "${CMAKE_CURRENT_FUNCTION_LIST_DIR}/realm-bindgen.ts"
+        COMMAND ${NPX} tsx -- "${CMAKE_CURRENT_FUNCTION_LIST_DIR}/realm-bindgen.ts" generate
             --spec "$<JOIN:${CORE_SPEC_FILE};${BINDGEN_SPECS},;--spec;>"
             "$<$<BOOL:${BINDGEN_OPTIN}>:--opt-in;${BINDGEN_OPTIN}>"
             --template "${BINDGEN_TEMPLATE}"

bindgen/src/program.ts

@@ -23,7 +23,7 @@ import path from "path";
 
 import { debug, enableDebugging } from "./debug";
 import { generate } from "./generator";
-import { OptInSpec, InvalidSpecError, parseOptInSpec, parseSpecs } from "./spec";
+import { OptInSpec, InvalidSpecError, parseOptInSpec, parseSpecs, generateSchema } from "./spec";
 import { Template, importTemplate } from "./templates";
 
 type GenerateOptions = {
@@ -109,13 +109,22 @@ program
         optInSpec = parseOptInSpec(optInPath);
       }
       generate({ rawSpec, optInSpec, template: await template, outputPath });
-      process.exit(0);
     } catch (err) {
       printError(err);
-      process.exit(1);
+      process.exitCode = 1;
     }
   });
 
+program.command("generate-schema").action(() => {
+  try {
+    console.log("Generating spec.schema.json");
+    generateSchema();
+  } catch (err) {
+    printError(err);
+    process.exitCode = 1;
+  }
+});
+
 program
   .command("validate")
   .addOption(specOption)
@@ -129,9 +138,8 @@ program
     try {
       parseSpecs(specPaths);
       console.log(chalk.green("Validation passed!"));
-      process.exit(0);
     } catch (err) {
       printError(err);
-      process.exit(1);
+      process.exitCode = 1;
     }
   });

bindgen/src/spec.ts

@@ -16,11 +16,13 @@
 //
 ////////////////////////////////////////////////////////////////////////////
 
-import Ajv, { ErrorObject } from "ajv";
+import Ajv, { ErrorObject, ValidateFunction } from "ajv";
 import { strict as assert } from "assert";
 import chalk from "chalk";
 import fs from "fs";
 import yaml from "yaml";
+import cp from "child_process";
+import path from "path";
 
 import {
   ClassSpec,
@@ -65,9 +67,42 @@ export class InvalidSpecError extends Error {
 }
 
 const ajv = new Ajv({ allowUnionTypes: true });
-const schemaFile = new URL("../generated/spec.schema.json", import.meta.url);
-const schemaJson = JSON.parse(fs.readFileSync(schemaFile, { encoding: "utf8" }));
-export const validate = ajv.compile<RelaxedSpec>(schemaJson);
+const rootPath = new URL("../..", import.meta.url).pathname;
+const schemaFile = path.resolve(rootPath, "bindgen/generated/spec.schema.json");
+
+export function generateSchema() {
+  cp.spawnSync(
+    "typescript-json-schema",
+    [
+      path.resolve(rootPath, "bindgen/tsconfig.json"),
+      "RelaxedSpec",
+      "--include",
+      path.resolve(rootPath, "bindgen/src/spec/relaxed-model.ts"),
+      "--out",
+      schemaFile,
+      "--required",
+      "--noExtraProps",
+      "--aliasRefs",
+    ],
+    { stdio: "inherit" },
+  );
+}
+
+let validate: ValidateFunction<RelaxedSpec> | null;
+
+function compileValidate(): ValidateFunction<RelaxedSpec> {
+  if (validate) {
+    return validate;
+  } else {
+    if (!fs.existsSync(schemaFile)) {
+      console.log("Generating spec.schema.json");
+      generateSchema();
+    }
+    const schemaJson = JSON.parse(fs.readFileSync(schemaFile, { encoding: "utf8" }));
+    validate = ajv.compile<RelaxedSpec>(schemaJson);
+    return validate;
+  }
+}
 
 function parseYaml(filePath: string): unknown {
   const text = fs.readFileSync(filePath, { encoding: "utf8" });
@@ -103,6 +138,7 @@ export function parseSpecs(specs: ReadonlyArray<string>): Spec {
 
 export function parseSpec(filePath: string): AnySpec {
   const parsed = parseYaml(filePath);
+  const validate = compileValidate();
   const isValid = validate(parsed);
   if (isValid) {
     return normalizeSpec(parsed);