--- layout: "docs" page_title: "artifact Stanza - Job Specification" sidebar_current: "docs-job-specification-artifact" description: |- The "artifact" stanza instructs Nomad to fetch and unpack a remote resource, such as a file, tarball, or binary, and permits downloading artifacts from a variety of locations using a URL as the input source. --- # `artifact` Stanza
Placement job -> group -> task -> **artifact**
The `artifact` stanza instructs Nomad to fetch and unpack a remote resource, such as a file, tarball, or binary. Nomad downloads artifacts using the popular [`go-getter`][go-getter] library, which permits downloading artifacts from a variety of locations using a URL as the input source. ```hcl job "docs" { group "example" { task "server" { artifact { source = "https://example.com/file.tar.gz" destination = "/tmp/file" options { checksum = "md5:df6a4178aec9fbdc1d6d7e3634d1bc33" } } } } } ``` Nomad supports downloading `http`, `https`, `git`, `hg` and `S3` artifacts. If these artifacts are archived (`zip`, `tgz`, `bz2`), they are automatically unarchived before the starting the task. ## `artifact` Parameters - `destination` `(string: "local/$1")` - Specifies the path to download the artifact, relative to the root of the task's directory. If omitted, the default value is to place the binary in `local/`. The destination is treated as a directory and source files will be downloaded into that directory path. - `options` `(map: nil)` - Specifies configuration parameters to fetch the artifact. The key-value pairs map directly to parameters appended to the supplied `source` URL. Please see the [`go-getter` documentation][go-getter] for a complete list of options and examples - `source` `(string: )` - Specifies the URL of the artifact to download. See [`go-getter`][go-getter] for details. ## `artifact` Examples The following examples only show the `artifact` stanzas. Remember that the `artifact` stanza is only valid in the placements listed above. ### Download File This example downloads the artifact from the provided URL and places it in `local/file.txt`. The `local/` path is relative to the task's directory. ```hcl artifact { source = "https://example.com/file.txt" } ``` ### Download with Custom Destination This example downloads the artifact from the provided URL and places it at `/tmp/example.txt`, as specified by the optional `destination` parameter. ```hcl artifact { source = "https://example.com/file.txt" destination = "/tmp/example.txt" } ``` ### Download and Unarchive This example downloads and unarchives the result in `local/file`. Because the source URL is an archive extension, Nomad will automatically decompress it: ```hcl artifact { source = "https://example.com/file.tar.gz" } ``` To disable automatic unarchiving, set the `archive` option to false: ```hcl artifact { source = "https://example.com/file.tar.gz" options { archive = false } } ``` ### Download and Verify Checksums This example downloads an artifact and verifies the resulting artifact's checksum before proceeding. If the checksum is invalid, an error will be returned. ```hcl artifact { source = "https://example.com/file.zip" options { checksum = "md5:df6a4178aec9fbdc1d6d7e3634d1bc33" } } ``` ### Download from an S3 Bucket These examples download artifacts from Amazon S3. There are several different types of [S3 bucket addressing][s3-bucket-addr] and [S3 region-specific endpoints][s3-region-endpoints]. This example uses path-based notation on a publicly-accessible bucket: ```hcl artifact { source = "https://s3-us-west-2.amazonaws.com/my-bucket-example/my_app.tar.gz" } ``` If a bucket requires authentication, it may be supplied via the `options` parameter: ```hcl artifact { options { aws_access_key_id = "" aws_access_key_secret = "" aws_access_token = "" } } ``` To force the S3-specific syntax, use the `s3::` prefix: ```hcl artifact { source = "s3::https://s3-eu-west-1.amazonaws.com/my-bucket-example/my_app.tar.gz" } ``` Alternatively you can use virtual hosted style: ```hcl artifact { source = "https://my-bucket-example.s3-eu-west-1.amazonaws.com/my_app.tar.gz" } ``` [go-getter]: https://github.com/hashicorp/go-getter "HashiCorp go-getter Library" [s3-bucket-addr]: http://docs.aws.amazon.com/AmazonS3/latest/dev/UsingBucket.html#access-bucket-intro "Amazon S3 Bucket Addressing" [s3-region-endpoints]: http://docs.aws.amazon.com/general/latest/gr/rande.html#s3_region "Amazon S3 Region Endpoints"