While creating a sample application using AWS Cloud9, getting an error, not able to create application.

Question

I am working on [AWS Lambda workshop](https://catalog.us-east-1.prod.workshops.aws/workshops/66943748-f648-4a43-8b44-da8cfcc53286/en-US), while creating sample application in AWS Cloud9 I am getting error 
![Error](/media/postImages/original/IMLKb8SbJVS_SNiDrmlcFaQQ)

Command to create sample application: sam init --runtime python3.7 --name sam-app

Here is a log:
environment $ sam init --runtime python3.7 --name sam-app
Which template source would you like to use?
        1 - AWS Quick Start Templates
        2 - Custom Template Location
Choice: 1
Traceback (most recent call last):
  File "/usr/local/bin/sam", line 8, in 
    sys.exit(cli())
  File "/usr/local/lib/python3.7/site-packages/click/core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/click/core.py", line 782, in main
    rv = self.invoke(ctx)
  File "/usr/local/lib/python3.7/site-packages/click/core.py", line 1259, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/local/lib/python3.7/site-packages/click/core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/local/lib/python3.7/site-packages/click/core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/samcli/commands/init/__init__.py", line 128, in wrapped
    return func(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/click/decorators.py", line 73, in new_func
    return ctx.invoke(f, obj, *args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/click/core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/samcli/lib/telemetry/metric.py", line 166, in wrapped
    raise exception  # pylint: disable=raising-bad-type
  File "/usr/local/lib/python3.7/site-packages/samcli/lib/telemetry/metric.py", line 124, in wrapped
    return_value = func(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/samcli/lib/utils/version_checker.py", line 41, in wrapped
    actual_result = func(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/samcli/cli/main.py", line 87, in wrapper
    return func(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/samcli/commands/init/__init__.py", line 274, in cli
    extra_context,
  File "/usr/local/lib/python3.7/site-packages/samcli/commands/init/__init__.py", line 359, in do_cli
    no_input,
  File "/usr/local/lib/python3.7/site-packages/samcli/commands/init/interactive_init_flow.py", line 65, in do_interactive
    location_opt_choice,
  File "/usr/local/lib/python3.7/site-packages/samcli/commands/init/interactive_init_flow.py", line 94, in generate_application
    architecture,
  File "/usr/local/lib/python3.7/site-packages/samcli/commands/init/interactive_init_flow.py", line 134, in _generate_from_use_case
    runtime_or_base_image, app_template, package_type_filter_value, dependency_manager
  File "/usr/local/lib/python3.7/site-packages/samcli/commands/init/init_templates.py", line 176, in get_preprocessed_manifest
    manifest_body = self._get_manifest()
  File "/usr/local/lib/python3.7/site-packages/samcli/commands/init/init_templates.py", line 221, in _get_manifest
    manifest_body = json.loads(body)
  File "/usr/lib64/python3.7/json/__init__.py", line 348, in loads
    return _default_decoder.decode(s)
  File "/usr/lib64/python3.7/json/decoder.py", line 340, in decode
    raise JSONDecodeError("Extra data", s, end)
json.decoder.JSONDecodeError: Extra data: line 1 column 4 (char 3)

Any help is appreaciated.

Answer

I had been facing the same issue. I started off with this Lambda lab in the AWS Workshops and came across the same error.

I would just like to add that the answer was helpful. For me, the first option - updating the SAM CLI version - worked and the rest of the lab went on without a hitch.

```
pip install aws-sam-cli --upgrade
```

The other possible reasons could also affect the outcome of the lab.

Answer

- SAM CLI Version: Check the version of the SAM CLI you are using. AWS updates these tools frequently and sometimes older versions may not work as expected. To check the version, run sam --version. If your SAM CLI is not up-to-date, consider updating it using pip: pip install aws-sam-cli --upgrade.

- JSON File: Check the JSON file that's being parsed. It appears the JSON file may have been improperly formatted, with some "extra" data. JSON files are particularly sensitive to correct syntax, so even a trailing comma or a misplaced bracket could cause an issue. You can use an online JSON validator to verify the file is properly formatted.

- Internet Connection: SAM CLI downloads the templates from the internet. So, ensure you have a stable internet connection. If your network is unstable or slow, the downloaded JSON might be incomplete leading to the error.

- Access rights: SAM CLI needs appropriate permissions to be able to create necessary resources for your app. Ensure you have the necessary permissions on your AWS account.

- Cloud9 Environment: Sometimes, issues can arise from the specific Cloud9 environment. If everything else appears to be in order, you might try creating a new environment and running the command there.

While creating a sample application using AWS Cloud9, getting an error, not able to create application.

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