fix: support more than 10 SSM parameters

README.md

@@ -117,7 +117,7 @@ override the SSM-resolved values. To avoid this:
 
 - Use `.env.with-ssm` instead of `.env` for SSM references
 - Or use environment variable substitution if your app supports it:
-  `${API_KEY:-SSM:/myapp/api-key}`
+  `API_KEY=${API_KEY:-SSM:/myapp/api-key}`
 
 ### 🚀 Deployment Considerations
 

src/start.ts

@@ -5,48 +5,41 @@ import { exec } from './utils/exec.js';
 import { getEnv } from './utils/env.js';
 import { replaceParams } from './utils/ssm.js';
 
-const main = async () => {
-  const argv = await yargs(hideBin(process.argv))
-    .usage('Usage: $0 [options] -- <command>')
-    .option('region', {
-      type: 'string',
-      description: 'The AWS region to use for SSM.',
-    })
-    .option('profile', {
-      type: 'string',
-      description: 'The AWS profile to use from your credentials file.',
-    })
-    .option('file', {
-      alias: 'f',
-      type: 'string',
-      description: 'The file to use for environment variables. (multiple files can be specified)',
-      default: ['.env', '.env.with-ssm'],
-    })
-    .demandCommand(1, 'Error: You must provide a command to execute after --')
-    .alias('h', 'help')
-    .epilogue('For more information, check the documentation.')
-    .parse();
+const argv = await yargs(hideBin(process.argv))
+  .usage('Usage: $0 [options] -- <command>')
+  .option('region', {
+    type: 'string',
+    description: 'The AWS region to use for SSM.',
+  })
+  .option('profile', {
+    type: 'string',
+    description: 'The AWS profile to use from your credentials file.',
+  })
+  .option('file', {
+    alias: 'f',
+    type: 'string',
+    description: 'The file to use for environment variables. (multiple files can be specified)',
+    default: ['.env', '.env.with-ssm'],
+  })
+  .demandCommand(1, 'Error: You must provide a command to execute after --')
+  .alias('h', 'help')
+  .epilogue('For more information, check the documentation.')
+  .parse();
 
-  const command = argv._[0] as string;
-  const commandArgs = argv._.slice(1).map(String);
+const command = argv._[0] as string;
+const commandArgs = argv._.slice(1).map(String);
 
-  if (!command) {
-    console.error('No command provided');
-    process.exit(1);
-  }
-
-  const files = argv.file && Array.isArray(argv.file) ? argv.file : [argv.file];
-  const hostEnv = await getEnv(files);
-  const env = await replaceParams(hostEnv);
-
-  exec({
-    command,
-    env,
-    args: commandArgs,
-  });
-};
-
-main().catch((err) => {
-  console.error(err);
+if (!command) {
+  console.error('No command provided');
   process.exit(1);
+}
+
+const files = argv.file && Array.isArray(argv.file) ? argv.file : [argv.file];
+const hostEnv = await getEnv(files);
+const env = await replaceParams(hostEnv);
+
+exec({
+  command,
+  env,
+  args: commandArgs,
 });

src/utils/cli.ts

@@ -1,14 +0,0 @@
-const splitArgs = (args: string[]) => {
-  const separatorIndex = args.indexOf('--');
-  const actionArgs = args.slice(0, separatorIndex);
-  const command = args[separatorIndex + 1];
-  const commandArgs = args.slice(separatorIndex + 2);
-
-  return {
-    actionArgs,
-    command,
-    commandArgs,
-  };
-};
-
-export { splitArgs };

src/utils/ssm.ts

@@ -1,4 +1,4 @@
-import { GetParametersCommand, SSMClient } from '@aws-sdk/client-ssm';
+import { GetParametersCommand, SSMClient, type Parameter } from '@aws-sdk/client-ssm';
 
 import { debug } from './debug.js';
 
@@ -30,18 +30,42 @@ const replaceParams = async (
     return env;
   }
 
-  const command = new GetParametersCommand({
-    Names: names,
-    WithDecryption: true,
-  });
+  // Chunk names into groups of 10 (AWS SSM GetParametersCommand limit)
+  const chunks: string[][] = [];
+  debug(`Chunking ${names.length} names into groups of 10`);
+  for (let i = 0; i < names.length; i += 10) {
+    chunks.push(names.slice(i, i + 10));
+  }
 
-  const response = await ssm.send(command);
-  if (response.InvalidParameters?.length || 0 > 0) {
-    console.error('Invalid SSM parameters', response.InvalidParameters);
+  debug(`Processing ${chunks.length} chunks`);
+
+  // Fetch parameters in chunks and combine results
+  const allParams: Parameter[] = [];
+  const allInvalidParams: string[] = [];
+
+  for (const chunk of chunks) {
+    const command = new GetParametersCommand({
+      Names: chunk,
+      WithDecryption: true,
+    });
+
+    const response = await ssm.send(command);
+
+    if (response.Parameters) {
+      allParams.push(...response.Parameters);
+    }
+
+    if (response.InvalidParameters) {
+      allInvalidParams.push(...response.InvalidParameters);
+    }
+  }
+
+  if (allInvalidParams.length > 0) {
+    console.error('Invalid SSM parameters', allInvalidParams);
     process.exit(1);
   }
 
-  const params = response.Parameters ?? [];
+  const params = allParams;
 
   return Object.fromEntries(
     Object.entries(env).map(([key, value]) => {