objstore is a Go module providing unified interface and efficient clients to work with various object storage providers.
Features:
- Ability to perform common operations with clear contract against most popular object storages.
- High focus on efficiency and reliability required for distributed databases on object storages.
- Optional built-in YAML based configuration definition for consistent configuration.
- Optional Prometheus metric instrumentation for bucket operations.
This moduile is battle-tested and used on high scale production by projects like Thanos, Loki, Cortex, Mimir, Tempo, Parca and more.
Contributions are very welcome! See our CONTRIBUTING.md for more information.
Thanos is an open source project and we value and welcome new contributors and members of the community. Here are ways to get in touch with the community:
- Slack: #thanos
- Issue Tracker: GitHub Issues
See [Adopters List](https://github.com/thanos-io/thanos/blob/main/website/data/adopters.yml.
This library was initially developed as a Thanos objstore package. Thanos uses object storage as primary storage for metrics and metadata related to them. This package ended up being used by other projects like Cortex, Loki, Mimir, Tempo, Parca and more.
Given reusability, Thanos community promoted this package to standalone Go module with smaller amount of dependencies.
See MAINTAINERS.md
The core this module is the Bucket interface:
// Bucket provides read and write access to an object storage bucket.
// NOTE: We assume strong consistency for write-read flow.
type Bucket interface {
io.Closer
BucketReader
// Upload the contents of the reader as an object into the bucket.
// Upload should be idempotent.
Upload(ctx context.Context, name string, r io.Reader) error
// Delete removes the object with the given name.
// If object does not exists in the moment of deletion, Delete should throw error.
Delete(ctx context.Context, name string) errorAll provider implementations have to implement Bucket interface that allows common read and write operations that all supported by all object providers. If you want to limit the code that will do bucket operation to only read access (smart idea, allowing to limit access permissions), you can use the BucketReader interface:
// BucketReader provides read access to an object storage bucket.
type BucketReader interface {
// Iter calls f for each entry in the given directory (not recursive.). The argument to f is the full
// object name including the prefix of the inspected directory.
// Entries are passed to function in sorted order.
Iter(ctx context.Context, dir string, f func(string) error, options ...IterOption) error
// Get returns a reader for the given object name.
Get(ctx context.Context, name string) (io.ReadCloser, error)
// GetRange returns a new range reader for the given object name and range.
GetRange(ctx context.Context, name string, off, length int64) (io.ReadCloser, error)
// Exists checks if the given object exists in the bucket.
Exists(ctx context.Context, name string) (bool, error)
// IsObjNotFoundErr returns true if error means that object is not found. Relevant to Get operations.
IsObjNotFoundErr(err error) bool
// Attributes returns information about the specified object.Those interfaces represent the object storage operations your code can use from objstore clients.
Generally, you have two ways of using objstore module:
First is to import the provider you want e.g. github.com/thanos-io/objstore/providers/s3 and instantiate it with available constructor (e.g. NewBucket).
The second option is to use the factory NewBucket(logger log.Logger, confContentYaml []byte, reg prometheus.Registerer, component string) that will instantiate the object storage client based on YAML file provided. The YAML file has generally the format like this:
type: <PROVIDER_TYPE>
config:
<PROVIDER_TYPE specific options>The exact option depends on provider and are in sections below.
NOTE: All code snippets are auto-generated from code and up-to-date.
Check out the Thanos documentation to see how Thanos uses this module.
Current object storage client implementations:
| Provider | Maturity | Aimed For | Auto-tested on CI | Maintainers |
|---|---|---|---|---|
| Google Cloud Storage | Stable | Production Usage | yes | @bwplotka |
| AWS/S3 (and all S3-compatible storages e.g disk-based Minio) | Stable | Production Usage | yes | @bwplotka |
| Azure Storage Account | Stable | Production Usage | no | @vglafirov,@phillebaba |
| OpenStack Swift | Beta (working PoC) | Production Usage | yes | @FUSAKLA |
| Tencent COS | Beta | Production Usage | no | @jojohappy,@hanjm |
| AliYun OSS | Beta | Production Usage | no | @shaulboozhiao,@wujinhu |
| Baidu BOS | Beta | Production Usage | no | @yahaa |
| Local Filesystem | Stable | Testing and Demo only | yes | @bwplotka |
| Oracle Cloud Infrastructure Object Storage | Beta | Production Usage | yes | @aarontams,@gaurav-05,@ericrrath |
Missing support to some object storage? Check out how to add your client section
NOTE: Currently Thanos requires strong consistency (write-read) for object store implementation for singleton Compaction purposes.
Thanos uses the minio client library to upload Prometheus data into AWS S3.
NOTE: S3 client was designed for AWS S3, but it can be configured against other S3-compatible object storages e.g Ceph
The S# object storage yaml configuration definition:
type: S3
config:
bucket: ""
endpoint: ""
region: ""
aws_sdk_auth: false
access_key: ""
insecure: false
signature_version2: false
secret_key: ""
put_user_metadata: {}
http_config:
idle_conn_timeout: 1m30s
response_header_timeout: 2m
insecure_skip_verify: false
tls_handshake_timeout: 10s
expect_continue_timeout: 1s
max_idle_conns: 100
max_idle_conns_per_host: 100
max_conns_per_host: 0
tls_config:
ca_file: ""
cert_file: ""
key_file: ""
server_name: ""
insecure_skip_verify: false
disable_compression: false
trace:
enable: false
list_objects_version: ""
bucket_lookup_type: auto
part_size: 67108864
sse_config:
type: ""
kms_key_id: ""
kms_encryption_context: {}
encryption_key: ""
sts_endpoint: ""
prefix: ""At a minimum, you will need to provide a value for the bucket, endpoint, access_key, and secret_key keys. The rest of the keys are optional.
However if you set aws_sdk_auth: true Thanos will use the default authentication methods of the AWS SDK for go based on known environment variables (AWS_PROFILE, AWS_WEB_IDENTITY_TOKEN_FILE ... etc) and known AWS config files (~/.aws/config). If you turn this on, then the bucket and endpoint are the required config keys.
The field prefix can be used to transparently use prefixes in your S3 bucket. This allows you to separate blocks coming from different sources into paths with different prefixes, making it easier to understand what's going on (i.e. you don't have to use Thanos tooling to know from where which blocks came).
The AWS region to endpoint mapping can be found in this link.
Make sure you use a correct signature version. Currently AWS requires signature v4, so it needs signature_version2: false. If you don't specify it, you will get an Access Denied error. On the other hand, several S3 compatible APIs use signature_version2: true.
You can configure the timeout settings for the HTTP client by setting the http_config.idle_conn_timeout and http_config.response_header_timeout keys. As a rule of thumb, if you are seeing errors like timeout awaiting response headers in your logs, you may want to increase the value of http_config.response_header_timeout.
Please refer to the documentation of the Transport type in the net/http package for detailed information on what each option does.
part_size is specified in bytes and refers to the minimum file size used for multipart uploads, as some custom S3 implementations may have different requirements. A value of 0 means to use a default 128 MiB size.
Set list_objects_version: "v1" for S3 compatible APIs that don't support ListObjectsV2 (e.g. some versions of Ceph). Default value ("") is equivalent to "v2".
http_config.tls_config allows configuring TLS connections. Please refer to the document of tls_config for detailed information on what each option does.
bucket_lookup_type can be auto, virtual-hosted or path. Read more about it here.
For debug and testing purposes you can set
-
insecure: trueto switch to plain insecure HTTP instead of HTTPS -
http_config.insecure_skip_verify: trueto disable TLS certificate verification (if your S3 based storage is using a self-signed certificate, for example) -
trace.enable: trueto enable the minio client's verbose logging. Each request and response will be logged into the debug logger, so debug level logging must be enabled for this functionality.
SSE can be configued using the sse_config. SSE-S3, SSE-KMS, and SSE-C are supported.
-
If type is set to
SSE-S3you do not need to configure other options. -
If type is set to
SSE-KMSyou must setkms_key_id. Thekms_encryption_contextis optional, as AWS provides a default encryption context. -
If type is set to
SSE-Cyou must provide a path to the encryption key usingencryption_key.
If the SSE Config block is set but the type is not one of SSE-S3, SSE-KMS, or SSE-C, an error is raised.
You will also need to apply the following AWS IAM policy for the user to access the KMS key:
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "KMSAccess",
"Effect": "Allow",
"Action": [
"kms:GenerateDataKey",
"kms:Encrypt",
"kms:Decrypt"
],
"Resource": "arn:aws:kms:<region>:<account>:key/<KMS key id>"
}
]
}By default Thanos will try to retrieve credentials from the following sources:
- From config file if BOTH
access_keyandsecret_keyare present. - From the standard AWS environment variable -
AWS_ACCESS_KEY_ID,AWS_SECRET_ACCESS_KEY - From
~/.aws/credentials - IAM credentials retrieved from an instance profile.
NOTE: Getting access key from config file and secret key from other method (and vice versa) is not supported.
Example working AWS IAM policy for user:
- For deployment (policy for Thanos services):
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "Statement",
"Effect": "Allow",
"Action": [
"s3:ListBucket",
"s3:GetObject",
"s3:DeleteObject",
"s3:PutObject"
],
"Resource": [
"arn:aws:s3:::<bucket>/*",
"arn:aws:s3:::<bucket>"
]
}
]
}(No bucket policy)
To test the policy, set env vars for S3 access for empty, not used bucket as well as:
THANOS_TEST_OBJSTORE_SKIP=GCS,AZURE,SWIFT,COS,ALIYUNOSS,OCI
THANOS_ALLOW_EXISTING_BUCKET_USE=true
And run: GOCACHE=off go test -v -run TestObjStore_AcceptanceTest_e2e ./pkg/...
- For testing (policy to run e2e tests):
We need access to CreateBucket and DeleteBucket and access to all buckets:
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "Statement",
"Effect": "Allow",
"Action": [
"s3:ListBucket",
"s3:GetObject",
"s3:DeleteObject",
"s3:PutObject",
"s3:CreateBucket",
"s3:DeleteBucket"
],
"Resource": [
"arn:aws:s3:::<bucket>/*",
"arn:aws:s3:::<bucket>"
]
}
]
}With this policy you should be able to run set THANOS_TEST_OBJSTORE_SKIP=GCS,AZURE,SWIFT,COS,ALIYUNOSS,OCI and unset S3_BUCKET and run all tests using make test.
Details about AWS policies: https://docs.aws.amazon.com/AmazonS3/latest/dev/using-with-s3-actions.html
If you want to use IAM credential retrieved from an instance profile, Thanos needs to authenticate through AWS STS. For this purposes you can specify your own STS Endpoint.
By default Thanos will use endpoint: https://sts.amazonaws.com and AWS region corresponding endpoints.
To configure Google Cloud Storage bucket as an object store you need to set bucket with GCS bucket name and configure Google Application credentials.
For example:
type: GCS
config:
bucket: ""
service_account: ""
prefix: ""Application credentials are configured via JSON file and only the bucket needs to be specified, the client looks for:
- A JSON file whose path is specified by the
GOOGLE_APPLICATION_CREDENTIALSenvironment variable. - A JSON file in a location known to the gcloud command-line tool. On Windows, this is
%APPDATA%/gcloud/application_default_credentials.json. On other systems,$HOME/.config/gcloud/application_default_credentials.json. - On Google App Engine it uses the
appengine.AccessTokenfunction. - On Google Compute Engine and Google App Engine Managed VMs, it fetches credentials from the metadata server. (In this final case any provided scopes are ignored.)
You can read more on how to get application credential json file in https://cloud.google.com/docs/authentication/production
Another possibility is to inline the ServiceAccount into the Thanos configuration and only maintain one file. This feature was added, so that the Prometheus Operator only needs to take care of one secret file.
type: GCS
config:
bucket: "thanos"
service_account: |-
{
"type": "service_account",
"project_id": "project",
"private_key_id": "abcdefghijklmnopqrstuvwxyz12345678906666",
"private_key": "-----BEGIN PRIVATE KEY-----\...\n-----END PRIVATE KEY-----\n",
"client_email": "[email protected]",
"client_id": "123456789012345678901",
"auth_uri": "https://accounts.google.com/o/oauth2/auth",
"token_uri": "https://oauth2.googleapis.com/token",
"auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
"client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/thanos%40gitpods.iam.gserviceaccount.com"
}Note: GCS Policies should be applied at the project level, not at the bucket level
For deployment:
Storage Object Creator and Storage Object Viewer
For testing:
Storage Object Admin for ability to create and delete temporary buckets.
To test the policy is working as expected, exec into the sidecar container, eg:
kubectl exec -it -n <namespace> <prometheus with sidecar pod name> -c <sidecar container name> -- /bin/shThen test that you can at least list objects in the bucket, eg:
thanos tools bucket ls --objstore.config="${OBJSTORE_CONFIG}"To use Azure Storage as Thanos object store, you need to precreate storage account from Azure portal or using Azure CLI. Follow the instructions from Azure Storage Documentation: https://docs.microsoft.com/en-us/azure/storage/common/storage-quickstart-create-account
Config file format is the following:
type: AZURE
config:
storage_account: ""
storage_account_key: ""
container: ""
endpoint: ""
max_retries: 0
msi_resource: ""
user_assigned_id: ""
pipeline_config:
max_tries: 0
try_timeout: 0s
retry_delay: 0s
max_retry_delay: 0s
reader_config:
max_retry_requests: 0
http_config:
idle_conn_timeout: 0s
response_header_timeout: 0s
insecure_skip_verify: false
tls_handshake_timeout: 0s
expect_continue_timeout: 0s
max_idle_conns: 0
max_idle_conns_per_host: 0
max_conns_per_host: 0
tls_config:
ca_file: ""
cert_file: ""
key_file: ""
server_name: ""
insecure_skip_verify: false
disable_compression: false
prefix: ""If msi_resource is used, authentication is done via system-assigned managed identity. The value for Azure should be https://<storage-account-name>.blob.core.windows.net.
If user_assigned_id is used, authentication is done via user-assigned managed identity. When using user_assigned_id the msi_resource defaults to https://<storage_account>.<endpoint>
The generic max_retries will be used as value for the pipeline_config's max_tries and reader_config's max_retry_requests. For more control, max_retries could be ignored (0) and one could set specific retry values.
Thanos uses ncw/swift client to upload Prometheus data into OpenStack Swift.
Below is an example configuration file for thanos to use OpenStack swift container as an object store. Note that if the name of a user, project or tenant is used one must also specify its domain by ID or name. Various examples for OpenStack authentication can be found in the official documentation.
By default, OpenStack Swift has a limit for maximum file size of 5 GiB. Thanos index files are often larger than that. To resolve this issue, Thanos uses Static Large Objects (SLO) which are uploaded as segments. These are by default put into the segments directory of the same container. The default limit for using SLO is 1 GiB which is also the maximum size of the segment. If you don't want to use the same container for the segments (best practise is to use <container_name>_segments to avoid polluting listing of the container objects) you can use the large_file_segments_container_name option to override the default and put the segments to other container. In rare cases you can switch to Dynamic Large Objects (DLO) by setting the use_dynamic_large_objects to true, but use it with caution since it even more relies on eventual consistency.
type: SWIFT
config:
auth_version: 0
auth_url: ""
username: ""
user_domain_name: ""
user_domain_id: ""
user_id: ""
password: ""
domain_id: ""
domain_name: ""
project_id: ""
project_name: ""
project_domain_id: ""
project_domain_name: ""
region_name: ""
container_name: ""
large_object_chunk_size: 1073741824
large_object_segments_container_name: ""
retries: 3
connect_timeout: 10s
timeout: 5m
use_dynamic_large_objects: false
prefix: ""To use Tencent COS as storage store, you should apply a Tencent Account to create an object storage bucket at first. Note that detailed from Tencent Cloud Documents: https://cloud.tencent.com/document/product/436
To configure Tencent Account to use COS as storage store you need to set these parameters in yaml format stored in a file:
type: COS
config:
bucket: ""
region: ""
app_id: ""
endpoint: ""
secret_key: ""
secret_id: ""
http_config:
idle_conn_timeout: 1m30s
response_header_timeout: 2m
insecure_skip_verify: false
tls_handshake_timeout: 10s
expect_continue_timeout: 1s
max_idle_conns: 100
max_idle_conns_per_host: 100
max_conns_per_host: 0
tls_config:
ca_file: ""
cert_file: ""
key_file: ""
server_name: ""
insecure_skip_verify: false
disable_compression: false
prefix: ""The secret_key and secret_id field is required. The http_config field is optional for optimize HTTP transport settings. There are two ways to configure the required bucket information:
- Provide the values of
bucket,regionandapp_idkeys. - Provide the values of
endpointkey with url format when you want to specify vpc internal endpoint. Please refer to the document of endpoint for more detail.
In order to use AliYun OSS object storage, you should first create a bucket with proper Storage Class , ACLs and get the access key on the AliYun cloud. Go to https://www.alibabacloud.com/product/oss for more detail.
The AliYun OSS object storage yaml configuration definition:
type: ALIYUNOSS
config:
endpoint: ""
bucket: ""
access_key_id: ""
access_key_secret: ""
prefix: ""In order to use Baidu BOS object storage, you should apply for a Baidu Account and create an object storage bucket first. Refer to Baidu Cloud Documents for more details. The Baidu BOS object storage yaml configuration definition:
type: BOS
config:
bucket: ""
endpoint: ""
access_key: ""
secret_key: ""
prefix: ""This storage type is used when user wants to store and access the bucket in the local filesystem. We treat filesystem the same way we would treat object storage, so all optimization for remote bucket applies even though, we might have the files locally.
NOTE: This storage type is experimental and might be inefficient. It is NOT advised to use it as the main storage for metrics in production environment. Particularly there is no planned support for distributed filesystems like NFS. This is mainly useful for testing and demos.
Filesystem "object storage" yaml configuration definition:
type: FILESYSTEM
config:
directory: ""
prefix: ""To configure Oracle Cloud Infrastructure (OCI) Object Storage as Thanos Object Store, you need to provide appropriate authentication credentials to your OCI tenancy. The OCI object storage client implementation for Thanos supports either the default keypair or instance principal authentication.
The default API signing key authentication provider leverages same configuration as the OCI CLI which is usually stored in at $HOME/.oci/config or via variable names starting with the string OCI_CLI. You can also use environment variables that start with TF_VAR. If the same configuration is found in multiple places the provider will prefer the first one.
The following example configures the provider to look for an existing API signing key for authentication:
type: OCI
config:
provider: "default"
bucket: ""
compartment_ocid: ""
part_size: "" // Optional part size to override the OCI default of 128 MiB, value is in bytes.
max_request_retries: "" // Optional maximum number of retries for a request.
request_retry_interval: "" // Optional sleep duration in seconds between retry requests.
http_config:
idle_conn_timeout: 1m30s // Optional maximum amount of time an idle (keep-alive) connection will remain idle before closing itself. Zero means no limit.
response_header_timeout: 2m // Optional amount of time to wait for a server's response headers after fully writing the request.
tls_handshake_timeout: 10s // Optional maximum amount of time waiting to wait for a TLS handshake. Zero means no timeout.
expect_continue_timeout: 1s // Optional amount of time to wait for a server's first response headers. Zero means no timeout and causes the body to be sent immediately.
insecure_skip_verify: false // Optional. If true, crypto/tls accepts any certificate presented by the server and any host name in that certificate.
max_idle_conns: 100 // Optional maximum number of idle (keep-alive) connections across all hosts. Zero means no limit.
max_idle_conns_per_host: 100 // Optional maximum idle (keep-alive) connections to keep per-host. If zero, DefaultMaxIdleConnsPerHost=2 is used.
max_conns_per_host: 0 // Optional maximum total number of connections per host.
disable_compression: false // Optional. If true, prevents the Transport from requesting compression.
client_timeout: 90s // Optional time limit for requests made by the HTTP Client.For Example:
type: OCI
config:
provider: "instance-principal"
bucket: ""
compartment_ocid: ""You can also include any of the optional configuration just like the example in Default Provider.
For Example:
type: OCI
config:
provider: "raw"
bucket: ""
compartment_ocid: ""
tenancy_ocid: ""
user_ocid: ""
region: ""
fingerprint: ""
privatekey: ""
passphrase: "" // Optional passphrase to encrypt the private API Signing keyYou can also include any of the optional configuration just like the example in Default Provider.
Following checklist allows adding new Go code client to supported providers:
- Create new directory under
./providers/<provider> - Implement objstore.Bucket interface
- Add
NewTestBucketconstructor for testing purposes, that creates and deletes temporary bucket. - Use created
NewTestBucketin ForeachStore method to ensure we can run tests against new provider. (In PR) - RUN the TestObjStoreAcceptanceTest against your provider to ensure it fits. Fix any found error until test passes. (In PR)
- Add client implementation to the factory in factory code. (Using as small amount of flags as possible in every command)
- Add client struct config to cfggen; to allow config auto generation.
At that point, anyone can use your provider by spec.