Migrating from v0.1 to v1 metadata server endpoint

If you use the 0.1 metadata server endpoint, read this guide to understand how to migrate to the v1 metadata server endpoint. If you are migrating from v1beta1 metadata server endpoint to v1, see Transitioning from v1beta1 metadata server endpoint.

To migrate from v0.1 to v1.0, you need to complete the following steps:

1. Review the differences between v0.1 and v1.0 metadata server endpoints.
2. Review the mapping tables to identify the new metadata server values.
3. Update queries to reflect these changes.
4. (Optional) Disable the v0.1 and v1beta1 endpoints.

Differences between the v0.1 and v1.0 metadata server endpoints

In general, the v0.1 metadata server endpoints differ from v1 in the following ways:

• The root used for querying metadata server endpoint has changed from http://metadata.google.internal/0.1/meta-data/ to http://metadata.google.internal/computeMetadata/v1/.

• v1 metadata server requests must include the Metadata-Flavor: Google header. For example, a request to the disks/ attribute now looks like the following:

  curl "http://metadata.google.internal/computeMetadata/v1/instance/disks/" -H "Metadata-Flavor: Google"
  

• Custom metadata can be queried at both the project and instance level.

  In the v0.1 metadata server, for the attributes/ property, both instance and project metadata values are in the same directory. If an attribute has both instance and project metadata values, the instance metadata value for a given key is returned.

  For v1 queries, the URL must specify whether instance or project metadata is requested. For example to query the sshKeys attribute, run one or both of the following:

  For sshKeys set on the project, run the following command:

  curl "http://metadata.google.internal/computeMetadata/v1/project/attributes/sshKeys" -H "Metadata-Flavor: Google"
  

  For sshKeys set on this instance, run the following command:

  curl "http://metadata.google.internal/computeMetadata/v1/instance/attributes/sshKeys" -H "Metadata-Flavor: Google"
  

• Some metadata entries in v0.1 return JSON objects. In the v1 metadata server, these metadata entries are organized by directories. This organization of entries lets you query specific index entries and values for these previously nested fields. For more information about querying a directory listing or accessing JSON objects in v1, see Attributes as directory listings.

Mapping 0.1 metadata server values to v1 values

Instance attributes

The following metadata entries are moved into the instance/ directory:

Project attributes

The following metadata entries are moved into the project/ directory:

Attributes that are moved

The following metadata entries are moved to a new endpoint:

Attributes that are renamed

The following metadata entries are renamed:

Attributes as directory listings

The following metadata entries returned JSON objects in v0.1 and are organized into directories in v1.

For these metadata entries, you can use either of the following methods to access the endpoints:

• Query the directory listings.
• Recursively query the v1 endpoints to get JSON objects similar to those in v0.1.

{"disks":[{
"deviceName":"persistent-disk-0",
"index":0,
"mode":"READ_WRITE",
"type":"PERSISTENT"}]}

[{"deviceName": "persistent-disk-0",
"index":0,
"mode":"READ_WRITE",
"type":"PERSISTENT"}]

{"networkInterface":
[{"accessConfiguration":
[{"externalIp":"35.194.6.47",
"type":"ONE_TO_ONE_NAT"}],
"ip":"10.128.0.4",
"mac":"42:01:0a:80:00:04","mtu":1460,
"network":"projects/12345/networks/default"}]}

[{"accessConfigs":
[{"externalIp":"35.194.6.47",
"type":"ONE_TO_ONE_NAT"}],
"dnsServers":["169.254.169.254"],
"forwardedIps":[],
"gateway":"10.128.0.1",
"ip":"10.128.0.4",
"ipAliases [],
"mac":"42:01:0a:80:00:04","mtu":1460,
"network":"projects/12345/networks/default",
"subnetmask":"255.255.240.0","targetInstanceIps":[]}]

{"serviceAccounts":
[{"scopes":["https://www.googleapis.com/auth/devstorage.read_only"],
"serviceAccount":"12345-compute@developer.gserviceaccount.com"}]}

{"123451-compute@developer.gserviceaccount.com":
{"aliases":["default"],
"email":"123451-compute@developer.gserviceaccount.com",
"scopes":["https://www.googleapis.com/auth/devstorage.read_only"]},
"default":{"aliases":["default"],
"email":"123451-compute@developer.gserviceaccount.com",
"scopes":["https://www.googleapis.com/auth/devstorage.read_only"]}}

{"scopes":["https://www.googleapis.com/auth/devstorage.read_only"],
"serviceAccount":"123451-compute@developer.gserviceaccount.com"}

{"aliases":["default"],
"email":"123451-compute@developer.gserviceaccount.com",
"scopes":["https://www.googleapis.com/auth/devstorage.read_only"]}

Querying OAuth2 access tokens

The following metadata entries return OAuth2 access tokens.

{"expires":1568854217,
"oauth2_access_token":"ya29.c.KmyIB0i4tH1xLzKGrqeeK6TGWEW3b18Lcq...."}

{"accessToken":"ya29.c.KmyIB0i4tH1xLNzKGrqeeK6TGWEW3b18Lcq.....",
"expiresAt":1568854217,"expiresIn":2022}

{"access_token":"ya29.c.KmyIB0i4tH1xLNzKGrqeeK6TGWEW3b18Lcq....",
"expires_in":2022,"token_type":"Bearer"}