Added CORS and Swagger docs

src/fetch/GET.ts

@@ -3,9 +3,12 @@ import { checkHealth } from "../health.js";
 import * as prometheus from "../prometheus.js";
 import * as sqlite from "../sqlite.js";
 import { db } from "../../index.js";
-import { toJSON } from "../http.js";
 import { Server } from "bun";
 import { logger } from "../logger.js";
+import openapi from "./openapi.js";
+import swaggerHtml  from "../../swagger/index.html"
+import swaggerFavicon from "../../swagger/favicon.png"
+import { NotFound, toFile, toJSON, toText } from "./cors.js";
 
 export default async function (req: Request, server: Server) {
     const { pathname, searchParams} = new URL(req.url);
@@ -21,7 +24,9 @@ export default async function (req: Request, server: Server) {
         return;
     }
 
-    if ( pathname === "/") return new Response(banner())
+    //if ( pathname === "/") return new Response(banner())
+    if ( pathname === "/" ) return toFile(Bun.file(swaggerHtml));
+    if ( pathname === "/favicon.png" ) return toFile(Bun.file(swaggerFavicon));
     if ( pathname === "/health") return checkHealth();
     if ( pathname === "/metrics") return new Response(await prometheus.registry.metrics());
     if ( pathname === "/moduleHash") return toJSON(sqlite.selectAll(db, "moduleHash"));

src/fetch/cors.ts

@@ -0,0 +1,37 @@
+import { BunFile } from "bun";
+
+export const CORS_HEADERS = new Headers({
+    "Access-Control-Allow-Origin": "*",
+    "Access-Control-Allow-Methods": "GET, POST, OPTIONS",
+    "Access-Control-Allow-Headers": "Content-Type, WWW-Authenticate",
+});
+export const JSON_HEADERS = new Headers({"Content-Type": "application/json"});
+export const TEXT_HEADERS = new Headers({"Content-Type": "text/plain; version=0.0.4; charset=utf-8"});
+
+export function appendHeaders(...args: Headers[]) {
+    const headers = new Headers(CORS_HEADERS); // CORS as default headers
+    for (const arg of args) {
+        for (const [key, value] of arg.entries()) {
+            headers.set(key, value);
+        }
+    }
+    return headers;
+};
+
+export function toJSON(body: any, status = 200, headers = new Headers()) {
+    const data = typeof body == "string" ? body : JSON.stringify(body, null, 2);
+    return new Response(data, { status, headers: appendHeaders(JSON_HEADERS, headers) });
+}
+
+export function toText(body: string, status = 200, headers = new Headers()) {
+    return new Response(body, { status, headers: appendHeaders(TEXT_HEADERS, headers) });
+}
+
+export function toFile(body: BunFile, status = 200, headers = new Headers()) {
+    const fileHeaders = new Headers({"Content-Type": body.type});
+    return new Response(body, { status, headers: appendHeaders(fileHeaders, headers) });
+}
+
+export const BadRequest = toText('Bad Request', 400);
+export const NotFound = toText('Not Found', 404);
+export const InternalServerError = toText("Internal Server Error", 500);

src/fetch/openapi.ts

@@ -0,0 +1,161 @@
+import pkg from "../../package.json" assert { type: "json" };
+
+import { OpenApiBuilder, SchemaObject, ExampleObject, ParameterObject } from "openapi3-ts/oas31";
+import { config } from "../config.js";
+import { getBlock } from "../queries.js";
+import { registry } from "../prometheus.js";
+import { makeQuery } from "../clickhouse/makeQuery.js";
+import { supportedChainsQuery } from "./chains.js";
+
+const TAGS = {
+  MONITORING: "Monitoring",
+  HEALTH: "Health",
+  USAGE: "Usage",
+  DOCS: "Documentation",
+} as const;
+
+const chains = await supportedChainsQuery();
+const block_example = (await makeQuery(await getBlock( new URLSearchParams({limit: "2"})))).data;
+
+const timestampSchema: SchemaObject = { anyOf: [
+    {type: "number"},
+    {type: "string", format: "date"},
+    {type: "string", format: "date-time"}
+  ]
+};
+const timestampExamples: ExampleObject = {
+  unix: { summary: `Unix Timestamp (seconds)` },
+  date: { summary: `Full-date notation`, value: '2023-10-18' },
+  datetime: { summary: `Date-time notation`, value: '2023-10-18T00:00:00Z'},
+}
+
+export default new OpenApiBuilder()
+  .addInfo({
+    title: pkg.name,
+    version: pkg.version,
+    description: pkg.description,
+    license: {name: pkg.license},
+  })
+  .addExternalDocs({ url: pkg.homepage, description: "Extra documentation" })
+  .addSecurityScheme("auth-key", { type: "http", scheme: "bearer" })
+  .addPath("/chains", {
+    get: {
+      tags: [TAGS.USAGE],
+      summary: 'Supported chains',
+      responses: {
+        200: {
+          description: "Array of chains",
+          content: {
+            "application/json": {
+              schema: { type: "array" },
+              example: chains,
+            }
+          },
+        },
+      },
+    },
+  })
+  .addPath("/block", {
+    get: {
+      tags: [TAGS.USAGE],
+      summary: "Get block",
+      description: "Get block by `block_number`, `block_id` or `timestamp`",
+      parameters: [
+        {
+          name: "chain",
+          in: "query",
+          description: "Filter by chain",
+          required: false,
+          schema: {enum: chains},
+        },
+        {
+          name: "block_number",
+          description: "Filter by Block number (ex: 18399498)",
+          in: "query",
+          required: false,
+          schema: { type: "number" },
+        },
+        {
+          name: "block_id",
+          in: "query",
+          description: "Filter by Block hash ID (ex: 00fef8cf2a2c73266f7c0b71fb5762f9a36419e51a7c05b0e82f9e3bacb859bc)",
+          required: false,
+          schema: { type: "string" },
+        },
+        {
+          name: 'timestamp',
+          in: 'query',
+          description: 'Filter by exact timestamp',
+          required: false,
+          schema: timestampSchema,
+          examples: timestampExamples,
+        },
+        {
+          name: "final_block",
+          description: "If true, only returns final blocks",
+          in: "query",
+          required: false,
+          schema: { type: "boolean" },
+        },
+        {
+          name: "sort_by",
+          in: "query",
+          description: "Sort by `block_number`",
+          required: false,
+          schema: {enum: ['ASC', 'DESC'] },
+        },
+        ...["greater_or_equals_by_timestamp", "greater_by_timestamp", "less_or_equals_by_timestamp", "less_by_timestamp"].map(name => {
+          return {
+            name,
+            in: "query",
+            description: "Filter " + name.replace(/_/g, " "),
+            required: false,
+            schema: timestampSchema,
+            examples: timestampExamples,
+          } as ParameterObject
+        }),
+        ...["greater_or_equals_by_block_number", "greater_by_block_number", "less_or_equals_by_block_number", "less_by_block_number"].map(name => {
+          return {
+            name,
+            in: "query",
+            description: "Filter " + name.replace(/_/g, " "),
+            required: false,
+            schema: { type: "number" },
+          } as ParameterObject
+        }),
+        {
+          name: "limit",
+          in: "query",
+          description: "Used to specify the number of records to return.",
+          required: false,
+          schema: { type: "number", maximum: config.maxLimit, minimum: 1 },
+        },
+      ],
+      responses: {
+        200: { description: "Array of blocks", content: { "application/json": { example: block_example, schema: { type: "array" } } } },
+        400: { description: "Bad request" },
+      },
+    },
+  })
+  .addPath("/health", {
+    get: {
+      tags: [TAGS.HEALTH],
+      summary: "Performs health checks and checks if the database is accessible",
+      responses: {200: { description: "OK", content: { "text/plain": {example: "OK"}} } },
+    },
+  })
+  .addPath("/metrics", {
+    get: {
+      tags: [TAGS.MONITORING],
+      summary: "Prometheus metrics",
+      responses: {200: { description: "Prometheus metrics", content: { "text/plain": { example: await registry.metrics(), schema: { type: "string" } } }}},
+    },
+  })
+  .addPath("/openapi", {
+    get: {
+      tags: [TAGS.DOCS],
+      summary: "OpenAPI specification",
+      responses: {200: {description: "OpenAPI JSON Specification", content: { "application/json": { schema: { type: "string" } } } }},
+    },
+  })
+  .getSpecAsJson();

src/types.d.ts

@@ -0,0 +1,14 @@
+declare module "*.png" {
+    const content: string;
+    export default content;
+  }
+
+declare module "*.html" {
+    const content: string;
+    export default content;
+}
+
+declare module "*.sql" {
+    const content: string;
+    export default content;
+}

swagger/index.html

@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
+    <meta
+      name="description"
+      content="SwaggerUI"
+    />
+    <title>Websocket API - SwaggerUI</title>
+    <link rel="stylesheet" href="https://unpkg.com/swagger-ui-dist@latest/swagger-ui.css" />
+    <link href="/favicon.png" rel="icon" type="image/x-icon">
+  </head>
+  <body>
+  <div id="swagger-ui"></div>
+  <script src="https://unpkg.com/swagger-ui-dist@latest/swagger-ui-bundle.js" crossorigin></script>
+  <script src="https://unpkg.com/swagger-ui-dist@latest/swagger-ui-standalone-preset.js" crossorigin></script>
+  <script>
+    window.onload = () => {
+      window.ui = SwaggerUIBundle({
+        url: 'https://substreams-erc20-api-production.up.railway.app/openapi',
+        dom_id: '#swagger-ui',
+        presets: [
+          SwaggerUIBundle.presets.apis,
+          SwaggerUIStandalonePreset
+        ],
+        layout: "StandaloneLayout",
+      });
+    };
+  </script>
+  </body>
+</html>