236 lines
		
	
	
		
			8.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			236 lines
		
	
	
		
			8.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
[//]: # "This README.md file is auto-generated, all changes to this file will be lost."
 | 
						|
[//]: # "To regenerate it, use `python -m synthtool`."
 | 
						|
<img src="https://avatars2.githubusercontent.com/u/2810941?v=3&s=96" alt="Google Cloud Platform logo" title="Google Cloud Platform" align="right" height="96" width="96"/>
 | 
						|
 | 
						|
# [GCP Metadata: Node.js Client](https://github.com/googleapis/gcp-metadata)
 | 
						|
 | 
						|
[](https://cloud.google.com/terms/launch-stages)
 | 
						|
[](https://www.npmjs.org/package/gcp-metadata)
 | 
						|
 | 
						|
 | 
						|
 | 
						|
 | 
						|
Get the metadata from a Google Cloud Platform environment
 | 
						|
 | 
						|
 | 
						|
A comprehensive list of changes in each version may be found in
 | 
						|
[the CHANGELOG](https://github.com/googleapis/gcp-metadata/blob/main/CHANGELOG.md).
 | 
						|
 | 
						|
* [GCP Metadata Node.js Client API Reference][client-docs]
 | 
						|
* [GCP Metadata Documentation][product-docs]
 | 
						|
* [github.com/googleapis/gcp-metadata](https://github.com/googleapis/gcp-metadata)
 | 
						|
 | 
						|
Read more about the client libraries for Cloud APIs, including the older
 | 
						|
Google APIs Client Libraries, in [Client Libraries Explained][explained].
 | 
						|
 | 
						|
[explained]: https://cloud.google.com/apis/docs/client-libraries-explained
 | 
						|
 | 
						|
**Table of contents:**
 | 
						|
 | 
						|
 | 
						|
* [Quickstart](#quickstart)
 | 
						|
 | 
						|
  * [Installing the client library](#installing-the-client-library)
 | 
						|
  * [Using the client library](#using-the-client-library)
 | 
						|
* [Samples](#samples)
 | 
						|
* [Versioning](#versioning)
 | 
						|
* [Contributing](#contributing)
 | 
						|
* [License](#license)
 | 
						|
 | 
						|
## Quickstart
 | 
						|
 | 
						|
### Installing the client library
 | 
						|
 | 
						|
```bash
 | 
						|
npm install gcp-metadata
 | 
						|
```
 | 
						|
 | 
						|
 | 
						|
### Using the client library
 | 
						|
 | 
						|
```javascript
 | 
						|
const gcpMetadata = require('gcp-metadata');
 | 
						|
 | 
						|
async function quickstart() {
 | 
						|
  // check to see if this code can access a metadata server
 | 
						|
  const isAvailable = await gcpMetadata.isAvailable();
 | 
						|
  console.log(`Is available: ${isAvailable}`);
 | 
						|
 | 
						|
  // Instance and Project level metadata will only be available if
 | 
						|
  // running inside of a Google Cloud compute environment such as
 | 
						|
  // Cloud Functions, App Engine, Kubernetes Engine, or Compute Engine.
 | 
						|
  // To learn more about the differences between instance and project
 | 
						|
  // level metadata, see:
 | 
						|
  // https://cloud.google.com/compute/docs/storing-retrieving-metadata#project-instance-metadata
 | 
						|
  if (isAvailable) {
 | 
						|
    // grab all top level metadata from the service
 | 
						|
    const instanceMetadata = await gcpMetadata.instance();
 | 
						|
    console.log('Instance metadata:');
 | 
						|
    console.log(instanceMetadata);
 | 
						|
 | 
						|
    // get all project level metadata
 | 
						|
    const projectMetadata = await gcpMetadata.project();
 | 
						|
    console.log('Project metadata:');
 | 
						|
    console.log(projectMetadata);
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
quickstart();
 | 
						|
 | 
						|
```
 | 
						|
 | 
						|
#### Check to see if the metadata server is available
 | 
						|
```js
 | 
						|
const isAvailable = await gcpMetadata.isAvailable();
 | 
						|
```
 | 
						|
 | 
						|
#### Access all metadata
 | 
						|
 | 
						|
```js
 | 
						|
const data = await gcpMetadata.instance();
 | 
						|
console.log(data); // ... All metadata properties
 | 
						|
```
 | 
						|
 | 
						|
#### Access specific properties
 | 
						|
```js
 | 
						|
const data = await gcpMetadata.instance('hostname');
 | 
						|
console.log(data); // ...Instance hostname
 | 
						|
const projectId = await gcpMetadata.project('project-id');
 | 
						|
console.log(projectId); // ...Project ID of the running instance
 | 
						|
```
 | 
						|
 | 
						|
#### Access nested properties with the relative path
 | 
						|
```js
 | 
						|
const data = await gcpMetadata.instance('service-accounts/default/email');
 | 
						|
console.log(data); // ...Email address of the Compute identity service account
 | 
						|
```
 | 
						|
 | 
						|
#### Access specific properties with query parameters
 | 
						|
```js
 | 
						|
const data = await gcpMetadata.instance({
 | 
						|
  property: 'tags',
 | 
						|
  params: { alt: 'text' }
 | 
						|
});
 | 
						|
console.log(data) // ...Tags as newline-delimited list
 | 
						|
```
 | 
						|
 | 
						|
#### Access with custom headers
 | 
						|
```js
 | 
						|
await gcpMetadata.instance({
 | 
						|
  headers: { 'no-trace': '1' }
 | 
						|
}); // ...Request is untraced
 | 
						|
```
 | 
						|
 | 
						|
### Take care with large number valued properties
 | 
						|
 | 
						|
In some cases number valued properties returned by the Metadata Service may be
 | 
						|
too large to be representable as JavaScript numbers. In such cases we return
 | 
						|
those values as `BigNumber` objects (from the [bignumber.js](https://github.com/MikeMcl/bignumber.js) library). Numbers
 | 
						|
that fit within the JavaScript number range will be returned as normal number
 | 
						|
values.
 | 
						|
 | 
						|
```js
 | 
						|
const id = await gcpMetadata.instance('id');
 | 
						|
console.log(id)  // ... BigNumber { s: 1, e: 18, c: [ 45200, 31799277581759 ] }
 | 
						|
console.log(id.toString()) // ... 4520031799277581759
 | 
						|
```
 | 
						|
 | 
						|
### Environment variables
 | 
						|
 | 
						|
* `GCE_METADATA_HOST`: provide an alternate host or IP to perform lookup against (useful, for example, you're connecting through a custom proxy server).
 | 
						|
 | 
						|
  For example:
 | 
						|
  ```
 | 
						|
  export GCE_METADATA_HOST='169.254.169.254'
 | 
						|
  ```
 | 
						|
 | 
						|
* `DETECT_GCP_RETRIES`: number representing number of retries that should be attempted on metadata lookup.
 | 
						|
 | 
						|
* `DEBUG_AUTH`: emit debugging logs
 | 
						|
 | 
						|
* `METADATA_SERVER_DETECTION`: configure desired metadata server availability check behavior.
 | 
						|
 | 
						|
  * `assume-present`: don't try to ping the metadata server, but assume it's present
 | 
						|
  * `none`: don't try to ping the metadata server, but don't try to use it either
 | 
						|
  * `bios-only`: treat the result of a BIOS probe as canonical (don't fall back to pinging)
 | 
						|
  * `ping-only`: skip the BIOS probe, and go straight to pinging
 | 
						|
 | 
						|
 | 
						|
## Samples
 | 
						|
 | 
						|
Samples are in the [`samples/`](https://github.com/googleapis/gcp-metadata/tree/main/samples) directory. Each sample's `README.md` has instructions for running its sample.
 | 
						|
 | 
						|
| Sample                      | Source Code                       | Try it |
 | 
						|
| --------------------------- | --------------------------------- | ------ |
 | 
						|
| Quickstart | [source code](https://github.com/googleapis/gcp-metadata/blob/main/samples/quickstart.js) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/gcp-metadata&page=editor&open_in_editor=samples/quickstart.js,samples/README.md) |
 | 
						|
 | 
						|
 | 
						|
 | 
						|
The [GCP Metadata Node.js Client API Reference][client-docs] documentation
 | 
						|
also contains samples.
 | 
						|
 | 
						|
## Supported Node.js Versions
 | 
						|
 | 
						|
Our client libraries follow the [Node.js release schedule](https://github.com/nodejs/release#release-schedule).
 | 
						|
Libraries are compatible with all current _active_ and _maintenance_ versions of
 | 
						|
Node.js.
 | 
						|
If you are using an end-of-life version of Node.js, we recommend that you update
 | 
						|
as soon as possible to an actively supported LTS version.
 | 
						|
 | 
						|
Google's client libraries support legacy versions of Node.js runtimes on a
 | 
						|
best-efforts basis with the following warnings:
 | 
						|
 | 
						|
* Legacy versions are not tested in continuous integration.
 | 
						|
* Some security patches and features cannot be backported.
 | 
						|
* Dependencies cannot be kept up-to-date.
 | 
						|
 | 
						|
Client libraries targeting some end-of-life versions of Node.js are available, and
 | 
						|
can be installed through npm [dist-tags](https://docs.npmjs.com/cli/dist-tag).
 | 
						|
The dist-tags follow the naming convention `legacy-(version)`.
 | 
						|
For example, `npm install gcp-metadata@legacy-8` installs client libraries
 | 
						|
for versions compatible with Node.js 8.
 | 
						|
 | 
						|
## Versioning
 | 
						|
 | 
						|
This library follows [Semantic Versioning](http://semver.org/).
 | 
						|
 | 
						|
 | 
						|
 | 
						|
This library is considered to be **stable**. The code surface will not change in backwards-incompatible ways
 | 
						|
unless absolutely necessary (e.g. because of critical security issues) or with
 | 
						|
an extensive deprecation period. Issues and requests against **stable** libraries
 | 
						|
are addressed with the highest priority.
 | 
						|
 | 
						|
 | 
						|
 | 
						|
 | 
						|
 | 
						|
 | 
						|
More Information: [Google Cloud Platform Launch Stages][launch_stages]
 | 
						|
 | 
						|
[launch_stages]: https://cloud.google.com/terms/launch-stages
 | 
						|
 | 
						|
## Contributing
 | 
						|
 | 
						|
Contributions welcome! See the [Contributing Guide](https://github.com/googleapis/gcp-metadata/blob/main/CONTRIBUTING.md).
 | 
						|
 | 
						|
Please note that this `README.md`, the `samples/README.md`,
 | 
						|
and a variety of configuration files in this repository (including `.nycrc` and `tsconfig.json`)
 | 
						|
are generated from a central template. To edit one of these files, make an edit
 | 
						|
to its templates in
 | 
						|
[directory](https://github.com/googleapis/synthtool).
 | 
						|
 | 
						|
## License
 | 
						|
 | 
						|
Apache Version 2.0
 | 
						|
 | 
						|
See [LICENSE](https://github.com/googleapis/gcp-metadata/blob/main/LICENSE)
 | 
						|
 | 
						|
[client-docs]: https://cloud.google.com/nodejs/docs/reference/gcp-metadata/latest
 | 
						|
[product-docs]: https://cloud.google.com/compute/docs/storing-retrieving-metadata
 | 
						|
[shell_img]: https://gstatic.com/cloudssh/images/open-btn.png
 | 
						|
[projects]: https://console.cloud.google.com/project
 | 
						|
[billing]: https://support.google.com/cloud/answer/6293499#enable-billing
 | 
						|
 | 
						|
[auth]: https://cloud.google.com/docs/authentication/external/set-up-adc-local
 |