refactor(gate): add err msg for missing env vars (#827)

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#### Migration notes

...

- [ ] The change comes with new or modified tests
- [ ] Hard-to-understand functions have explanatory comments
- [ ] End-user documentation is updated to reflect the change

.ghjk/lock.json

@@ -1978,7 +1978,7 @@
               ]
             }
           },
-          "defaultEnv": "ci",
+          "defaultEnv": "dev",
           "envsNamed": {
             "main": "bciqkx2kodz5dx5pv3hjcc4vpirphyetattk4oks5pucb7dsqrgwzqwa",
             "_wasm": "bciqk7aif25pqtsyncbnbdapte4lixsodypfxvmkepsuey74vgr4zb5q",

CHANGELOG.md

@@ -3591,6 +3591,3 @@ _N/A_
 - [ ] End-user documentation is updated to reflect the change
 
 </details>
-
-
-

src/typegate/src/config/types.ts

@@ -1,16 +1,41 @@
 // Copyright Metatype OÜ, licensed under the Elastic License 2.0.
 // SPDX-License-Identifier: Elastic-2.0
 
-import { z } from "zod";
+import { z, RefinementCtx } from "zod";
 import { decodeBase64 } from "@std/encoding/base64";
 import type { RedisConnectOptions } from "redis";
 import type { S3ClientConfig } from "aws-sdk/client-s3";
 
 const zBooleanString = z.preprocess(
   (a: unknown) => z.coerce.string().parse(a) === "true",
-  z.boolean(),
+  z.boolean()
 );
 
+const addMissingEnvVarIssue = (envVar: string, ctx: RefinementCtx) => {
+  ctx.addIssue({
+    code: z.ZodIssueCode.custom,
+    message: `Error: Env var ${envVar} is not configured.`,
+  });
+
+  return z.NEVER;
+};
+
+const refineEnvVar = (envVar: string) => z.string().optional().transform((s: string | undefined, ctx) => {
+  if (s === undefined) {
+    return addMissingEnvVarIssue(envVar, ctx);
+  }
+
+  return s;
+});
+
+const refineURLEnvVar = (envVar: string) => z.string().optional().transform((s: string | undefined, ctx) => {
+  if (s === undefined) {
+    return addMissingEnvVarIssue(envVar, ctx);
+  }
+
+  return new URL(s);
+});
+
 export const globalConfigSchema = z.object({
   debug: zBooleanString,
   // To be set to false when running from source.
@@ -37,44 +62,22 @@ export const typegateConfigBaseSchema = z.object({
     .optional()
     .transform((s: string | undefined, ctx) => {
       if (s === undefined) {
-        ctx.addIssue({
-          code: z.ZodIssueCode.custom,
-          message:
-            "Error: Env var TG_SECRET is not configured. Exiting from the application.",
-        });
-
-        return z.NEVER;
+        return addMissingEnvVarIssue("TG_SECRET", ctx);
       }
 
       const bytes = decodeBase64(s);
       if (bytes.length != 64) {
         ctx.addIssue({
           code: z.ZodIssueCode.custom,
-          message:
-            `Base64 contains ${bytes.length} instead of 64 bytes (use openssl rand -base64 64 | tr -d '\n')`,
+          message: `Base64 contains ${bytes.length} instead of 64 bytes (use openssl rand -base64 64 | tr -d '\n')`,
         });
       }
       return bytes;
     }),
   timer_max_timeout_ms: z.coerce.number().positive().max(60000),
   timer_destroy_resources: z.boolean(),
   timer_policy_eval_retries: z.number().nonnegative().max(5),
-  tg_admin_password: z
-    .string()
-    .optional()
-    .transform((s: string | undefined, ctx) => {
-      if (s === undefined) {
-        ctx.addIssue({
-          code: z.ZodIssueCode.custom,
-          message:
-            "Error: Env var TG_ADMIN_PASSWORD is not configured. Exiting from the application.",
-        });
-
-        return z.NEVER;
-      }
-
-      return s;
-    }),
+  tg_admin_password: refineEnvVar("TG_ADMIN_PASSWORD"),
   tmp_dir: z.string(),
   jwt_max_duration_sec: z.coerce.number().positive(),
   jwt_refresh_duration_sec: z.coerce.number().positive(),
@@ -88,12 +91,12 @@ export type TypegateConfigBase = z.infer<typeof typegateConfigBaseSchema>;
 // These config entries are only accessible on a Typegate instance.
 // They are not read from a global variable to enable test isolation and configurability.
 export const syncConfigSchema = z.object({
-  redis_url: z.string().transform((s) => new URL(s)),
-  s3_host: z.string().transform((s) => new URL(s)),
-  s3_region: z.string(),
-  s3_bucket: z.string(),
-  s3_access_key: z.string(),
-  s3_secret_key: z.string(),
+  redis_url: refineURLEnvVar("SYNC_REDIS_URL"),
+  s3_host: refineURLEnvVar("SYNC_S3_HOST"),
+  s3_region: refineEnvVar("SYNC_S3_REGION"),
+  s3_bucket: refineEnvVar("SYNC_S3_BUCKET"),
+  s3_access_key: refineEnvVar("SYNC_S3_ACCESS_KEY"),
+  s3_secret_key: refineEnvVar("SYNC_S3_SECRET_KEY"),
   s3_path_style: zBooleanString.default(false),
 });
 export type SyncConfig = z.infer<typeof syncConfigSchema>;

tests/sync/sync_config_test.ts

@@ -72,11 +72,9 @@ Deno.test("test sync config", async (t) => {
         "s3_access_key",
         "s3_secret_key",
       ].map((k) => ({
-        code: "invalid_type",
-        expected: "string",
-        message: "Required",
+        code: "custom",
+        message: `Error: Env var SYNC_${k.toUpperCase()} is not configured.`,
         path: [k],
-        received: "undefined",
       })),
     );
 
@@ -90,11 +88,9 @@ Deno.test("test sync config", async (t) => {
     Deno.env.set("SYNC_S3_BUCKET", "bucket");
     assertInvalidSyncConfig([
       {
-        code: "invalid_type",
-        expected: "string",
-        message: "Required",
+        code: "custom",
+        message: "Error: Env var SYNC_S3_SECRET_KEY is not configured.",
         path: ["s3_secret_key"],
-        received: "undefined",
       },
     ]);
   });