Files
RpgRoller/scripts/generate-api-client.mjs

279 lines
9.2 KiB
JavaScript

import { mkdir, readFile, writeFile } from "node:fs/promises";
import path from "node:path";
import { fileURLToPath } from "node:url";
const scriptDirectory = path.dirname(fileURLToPath(import.meta.url));
const repoRoot = path.resolve(scriptDirectory, "..");
const openApiPath = path.join(repoRoot, "openapi", "RpgRoller.json");
const outputPath = path.join(repoRoot, "RpgRoller", "frontend", "generated", "api-client.ts");
function pascalCase(value) {
return value
.replace(/[^a-zA-Z0-9]+/g, " ")
.trim()
.split(/\s+/)
.map((part) => part.charAt(0).toUpperCase() + part.slice(1))
.join("");
}
function escapePathSegment(segment) {
return segment.replaceAll("\\", "\\\\").replaceAll("\"", "\\\"");
}
function mapSimpleType(schema) {
switch (schema?.type) {
case "integer":
case "number":
return "number";
case "boolean":
return "boolean";
case "string":
return "string";
default:
return null;
}
}
function schemaRefName(schema) {
if (typeof schema?.$ref !== "string") {
return null;
}
const refPrefix = "#/components/schemas/";
if (!schema.$ref.startsWith(refPrefix)) {
throw new Error(`Unsupported schema ref: ${schema.$ref}`);
}
return schema.$ref.substring(refPrefix.length);
}
function toTypeScriptType(schema, components, forProperty = false) {
if (!schema || typeof schema !== "object") {
return "unknown";
}
const refName = schemaRefName(schema);
if (refName !== null) {
return refName;
}
const simpleType = mapSimpleType(schema);
if (simpleType !== null) {
return simpleType;
}
if (schema.type === "array") {
const itemType = toTypeScriptType(schema.items, components);
return `Array<${itemType}>`;
}
if (schema.type === "object") {
const propertyEntries = Object.entries(schema.properties ?? {});
if (propertyEntries.length === 0) {
return "Record<string, unknown>";
}
const required = new Set(Array.isArray(schema.required) ? schema.required : []);
const fields = propertyEntries.map(([name, propertySchema]) => {
const typeName = toTypeScriptType(propertySchema, components, true);
const optional = required.has(name) ? "" : "?";
return `${name}${optional}: ${typeName};`;
});
if (forProperty) {
return `{ ${fields.join(" ")} }`;
}
return `{\n${fields.map((field) => ` ${field}`).join("\n")}\n}`;
}
if (Array.isArray(schema.oneOf) && schema.oneOf.length > 0) {
return schema.oneOf.map((option) => toTypeScriptType(option, components, true)).join(" | ");
}
if (Array.isArray(schema.anyOf) && schema.anyOf.length > 0) {
return schema.anyOf.map((option) => toTypeScriptType(option, components, true)).join(" | ");
}
return "unknown";
}
function schemaToInterface(name, schema, components) {
const required = new Set(Array.isArray(schema.required) ? schema.required : []);
const fields = Object.entries(schema.properties ?? {}).map(([propertyName, propertySchema]) => {
const typeName = toTypeScriptType(propertySchema, components, true);
const optional = required.has(propertyName) ? "" : "?";
return ` ${propertyName}${optional}: ${typeName};`;
});
if (fields.length === 0) {
return `export type ${name} = Record<string, unknown>;`;
}
return `export interface ${name} {\n${fields.join("\n")}\n}`;
}
function collectOperations(document, components) {
const operations = [];
for (const [pathKey, pathItem] of Object.entries(document.paths ?? {})) {
const pathLevelParameters = Array.isArray(pathItem?.parameters) ? pathItem.parameters : [];
for (const [method, operation] of Object.entries(pathItem ?? {})) {
if (operation === null || typeof operation !== "object") {
continue;
}
if (typeof operation.operationId !== "string" || operation.operationId.length === 0) {
throw new Error(`Missing operationId for ${method.toUpperCase()} ${pathKey}`);
}
operations.push({
operationId: operation.operationId,
method: method.toUpperCase(),
path: pathKey,
parameters: collectPathParameters([...pathLevelParameters, ...(operation.parameters ?? [])]),
responseType: resolveResponseType(operation, components)
});
}
}
if (operations.length === 0) {
throw new Error("OpenAPI document does not define any operations.");
}
return operations.sort((left, right) => left.operationId.localeCompare(right.operationId));
}
function collectPathParameters(parameters) {
const seen = new Set();
const result = [];
for (const parameter of parameters) {
if (!parameter || parameter.in !== "path" || typeof parameter.name !== "string") {
continue;
}
if (seen.has(parameter.name)) {
continue;
}
seen.add(parameter.name);
const simpleType = mapSimpleType(parameter.schema);
result.push({
name: parameter.name,
type: simpleType ?? "string"
});
}
return result;
}
function resolveResponseType(operation, components) {
const responses = operation.responses ?? {};
const successCodes = Object.keys(responses)
.filter((code) => code.startsWith("2"))
.sort();
if (successCodes.length === 0) {
return "void";
}
for (const code of successCodes) {
const content = responses[code]?.content?.["application/json"];
const schema = content?.schema;
if (schema) {
return toTypeScriptType(schema, components);
}
}
return "void";
}
function buildSchemaTypes(document) {
const components = document.components ?? {};
const schemas = components.schemas ?? {};
const schemaEntries = Object.entries(schemas).sort(([left], [right]) => left.localeCompare(right));
const declarations = schemaEntries.map(([name, schema]) => {
if (!schema || typeof schema !== "object") {
return `export type ${name} = unknown;`;
}
return schemaToInterface(name, schema, components);
});
return declarations.join("\n\n");
}
function buildClientSource(operations, schemaTypes) {
const operationEntries = operations
.map((operation) => ` ${operation.operationId}: { method: "${operation.method}", path: "${escapePathSegment(operation.path)}" }`)
.join(",\n");
const helper = `
type ApiOperation = {
method: string;
path: string;
};
export const apiOperations = {
${operationEntries}
} as const satisfies Record<string, ApiOperation>;
`.trim();
const sendFunction = `
async function send<TResult>(operation: ApiOperation, pathParams: Record<string, string | number | boolean> = {}): Promise<TResult> {
let resolvedPath = operation.path;
for (const [key, value] of Object.entries(pathParams)) {
resolvedPath = resolvedPath.replace(\`{\${key}}\`, encodeURIComponent(String(value)));
}
const response = await fetch(resolvedPath, {
method: operation.method,
headers: {
"Accept": "application/json"
}
});
if (!response.ok) {
const errorPayload: unknown = await response.json().catch(() => ({ error: "Unknown API error." }));
if (errorPayload && typeof errorPayload === "object" && "error" in errorPayload && typeof errorPayload.error === "string") {
throw new Error(errorPayload.error);
}
throw new Error(\`Request failed with status \${response.status}\`);
}
return response.json() as Promise<TResult>;
}
`.trim();
const exports = operations
.map((operation) => {
const params = operation.parameters;
const signature = params.length === 0 ? "" : params.map((parameter) => `${parameter.name}: ${parameter.type}`).join(", ");
const pathParams = params.length === 0
? "{}"
: `{ ${params.map((parameter) => `${parameter.name}: ${parameter.name}`).join(", ")} }`;
const responseType = operation.responseType ?? "unknown";
return `export async function ${operation.operationId}(${signature}): Promise<${responseType}> {\n return send<${responseType}>(apiOperations.${operation.operationId}, ${pathParams});\n}`;
})
.join("\n\n");
return `/* This file is generated by scripts/generate-api-client.mjs. */\n\n${schemaTypes}\n\n${helper}\n\n${sendFunction}\n\n${exports}\n`;
}
const openApiText = await readFile(openApiPath, "utf8");
const document = JSON.parse(openApiText);
const components = document.components ?? {};
const operations = collectOperations(document, components);
const schemaTypes = buildSchemaTypes(document);
const clientSource = buildClientSource(operations, schemaTypes);
await mkdir(path.dirname(outputPath), { recursive: true });
await writeFile(outputPath, clientSource, "utf8");
console.log(`Generated API client: ${path.relative(repoRoot, outputPath)}`);