github.com/npaton/distribution@v2.3.1-rc.0+incompatible/docs/spec/manifest-v2-1.md (about) 1 <!--[metadata]> 2 +++ 3 draft = true 4 +++ 5 <![end-metadata]--> 6 7 # Image Manifest Version 2, Schema 1 8 9 This document outlines the format of of the V2 image manifest. The image 10 manifest described herein was introduced in the Docker daemon in the [v1.3.0 11 release](https://github.com/docker/docker/commit/9f482a66ab37ec396ac61ed0c00d59122ac07453). 12 It is a provisional manifest to provide a compatibility with the [V1 Image 13 format](https://github.com/docker/docker/blob/master/image/spec/v1.md), as the 14 requirements are defined for the [V2 Schema 2 15 image](https://github.com/docker/distribution/pull/62). 16 17 18 Image manifests describe the various constituents of a docker image. Image 19 manifests can be serialized to JSON format with the following media types: 20 21 Manifest Type | Media Type 22 ------------- | ------------- 23 manifest | "application/vnd.docker.distribution.manifest.v1+json" 24 signed manifest | "application/vnd.docker.distribution.manifest.v1+prettyjws" 25 26 *Note that "application/json" will also be accepted for schema 1.* 27 28 References: 29 30 - [Proposal: JSON Registry API V2.1](https://github.com/docker/docker/issues/9015) 31 - [Proposal: Provenance step 1 - Transform images for validation and verification](https://github.com/docker/docker/issues/8093) 32 33 ## *Manifest* Field Descriptions 34 35 Manifest provides the base accessible fields for working with V2 image format 36 in the registry. 37 38 - **`name`** *string* 39 40 name is the name of the image's repository 41 42 - **`tag`** *string* 43 44 tag is the tag of the image 45 46 - **`architecture`** *string* 47 48 architecture is the host architecture on which this image is intended to 49 run. This is for information purposes and not currently used by the engine 50 51 - **`fsLayers`** *array* 52 53 fsLayers is a list of filesystem layer blob sums contained in this image. 54 55 An fsLayer is a struct consisting of the following fields 56 - **`blobSum`** *digest.Digest* 57 58 blobSum is the digest of the referenced filesystem image layer. A 59 digest must be a sha256 hash. 60 61 62 - **`history`** *array* 63 64 history is a list of unstructured historical data for v1 compatibility. It 65 contains ID of the image layer and ID of the layer's parent layers. 66 67 history is a struct consisting of the following fields 68 - **`v1Compatibility`** string 69 70 V1Compatibility is the raw V1 compatibility information. This will 71 contain the JSON object describing the V1 of this image. 72 73 - **`schemaVersion`** *int* 74 75 SchemaVersion is the image manifest schema that this image follows. 76 77 >**Note**:the length of `history` must be equal to the length of `fsLayers` and 78 >entries in each are correlated by index. 79 80 ## Signed Manifests 81 82 Signed manifests provides an envelope for a signed image manifest. A signed 83 manifest consists of an image manifest along with an additional field 84 containing the signature of the manifest. 85 86 The docker client can verify signed manifests and displays a message to the user. 87 88 ### Signing Manifests 89 90 Image manifests can be signed in two different ways: with a *libtrust* private 91 key or an x509 certificate chain. When signing with an x509 certificate chain, 92 the public key of the first element in the chain must be the public key 93 corresponding with the sign key. 94 95 ### Signed Manifest Field Description 96 97 Signed manifests include an image manifest and a list of signatures generated 98 by *libtrust*. A signature consists of the following fields: 99 100 101 - **`header`** *[JOSE](http://tools.ietf.org/html/draft-ietf-jose-json-web-signature-31#section-2)* 102 103 A [JSON Web Signature](http://self-issued.info/docs/draft-ietf-jose-json-web-signature.html) 104 105 - **`signature`** *string* 106 107 A signature for the image manifest, signed by a *libtrust* private key 108 109 - **`protected`** *string* 110 111 The signed protected header 112 113 ## Example Manifest 114 115 *Example showing the official 'hello-world' image manifest.* 116 117 ``` 118 { 119 "name": "hello-world", 120 "tag": "latest", 121 "architecture": "amd64", 122 "fsLayers": [ 123 { 124 "blobSum": "sha256:5f70bf18a086007016e948b04aed3b82103a36bea41755b6cddfaf10ace3c6ef" 125 }, 126 { 127 "blobSum": "sha256:5f70bf18a086007016e948b04aed3b82103a36bea41755b6cddfaf10ace3c6ef" 128 }, 129 { 130 "blobSum": "sha256:cc8567d70002e957612902a8e985ea129d831ebe04057d88fb644857caa45d11" 131 }, 132 { 133 "blobSum": "sha256:5f70bf18a086007016e948b04aed3b82103a36bea41755b6cddfaf10ace3c6ef" 134 } 135 ], 136 "history": [ 137 { 138 "v1Compatibility": "{\"id\":\"e45a5af57b00862e5ef5782a9925979a02ba2b12dff832fd0991335f4a11e5c5\",\"parent\":\"31cbccb51277105ba3ae35ce33c22b69c9e3f1002e76e4c736a2e8ebff9d7b5d\",\"created\":\"2014-12-31T22:57:59.178729048Z\",\"container\":\"27b45f8fb11795b52e9605b686159729b0d9ca92f76d40fb4f05a62e19c46b4f\",\"container_config\":{\"Hostname\":\"8ce6509d66e2\",\"Domainname\":\"\",\"User\":\"\",\"Memory\":0,\"MemorySwap\":0,\"CpuShares\":0,\"Cpuset\":\"\",\"AttachStdin\":false,\"AttachStdout\":false,\"AttachStderr\":false,\"PortSpecs\":null,\"ExposedPorts\":null,\"Tty\":false,\"OpenStdin\":false,\"StdinOnce\":false,\"Env\":[\"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\"],\"Cmd\":[\"/bin/sh\",\"-c\",\"#(nop) CMD [/hello]\"],\"Image\":\"31cbccb51277105ba3ae35ce33c22b69c9e3f1002e76e4c736a2e8ebff9d7b5d\",\"Volumes\":null,\"WorkingDir\":\"\",\"Entrypoint\":null,\"NetworkDisabled\":false,\"MacAddress\":\"\",\"OnBuild\":[],\"SecurityOpt\":null,\"Labels\":null},\"docker_version\":\"1.4.1\",\"config\":{\"Hostname\":\"8ce6509d66e2\",\"Domainname\":\"\",\"User\":\"\",\"Memory\":0,\"MemorySwap\":0,\"CpuShares\":0,\"Cpuset\":\"\",\"AttachStdin\":false,\"AttachStdout\":false,\"AttachStderr\":false,\"PortSpecs\":null,\"ExposedPorts\":null,\"Tty\":false,\"OpenStdin\":false,\"StdinOnce\":false,\"Env\":[\"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\"],\"Cmd\":[\"/hello\"],\"Image\":\"31cbccb51277105ba3ae35ce33c22b69c9e3f1002e76e4c736a2e8ebff9d7b5d\",\"Volumes\":null,\"WorkingDir\":\"\",\"Entrypoint\":null,\"NetworkDisabled\":false,\"MacAddress\":\"\",\"OnBuild\":[],\"SecurityOpt\":null,\"Labels\":null},\"architecture\":\"amd64\",\"os\":\"linux\",\"Size\":0}\n" 139 }, 140 { 141 "v1Compatibility": "{\"id\":\"e45a5af57b00862e5ef5782a9925979a02ba2b12dff832fd0991335f4a11e5c5\",\"parent\":\"31cbccb51277105ba3ae35ce33c22b69c9e3f1002e76e4c736a2e8ebff9d7b5d\",\"created\":\"2014-12-31T22:57:59.178729048Z\",\"container\":\"27b45f8fb11795b52e9605b686159729b0d9ca92f76d40fb4f05a62e19c46b4f\",\"container_config\":{\"Hostname\":\"8ce6509d66e2\",\"Domainname\":\"\",\"User\":\"\",\"Memory\":0,\"MemorySwap\":0,\"CpuShares\":0,\"Cpuset\":\"\",\"AttachStdin\":false,\"AttachStdout\":false,\"AttachStderr\":false,\"PortSpecs\":null,\"ExposedPorts\":null,\"Tty\":false,\"OpenStdin\":false,\"StdinOnce\":false,\"Env\":[\"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\"],\"Cmd\":[\"/bin/sh\",\"-c\",\"#(nop) CMD [/hello]\"],\"Image\":\"31cbccb51277105ba3ae35ce33c22b69c9e3f1002e76e4c736a2e8ebff9d7b5d\",\"Volumes\":null,\"WorkingDir\":\"\",\"Entrypoint\":null,\"NetworkDisabled\":false,\"MacAddress\":\"\",\"OnBuild\":[],\"SecurityOpt\":null,\"Labels\":null},\"docker_version\":\"1.4.1\",\"config\":{\"Hostname\":\"8ce6509d66e2\",\"Domainname\":\"\",\"User\":\"\",\"Memory\":0,\"MemorySwap\":0,\"CpuShares\":0,\"Cpuset\":\"\",\"AttachStdin\":false,\"AttachStdout\":false,\"AttachStderr\":false,\"PortSpecs\":null,\"ExposedPorts\":null,\"Tty\":false,\"OpenStdin\":false,\"StdinOnce\":false,\"Env\":[\"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\"],\"Cmd\":[\"/hello\"],\"Image\":\"31cbccb51277105ba3ae35ce33c22b69c9e3f1002e76e4c736a2e8ebff9d7b5d\",\"Volumes\":null,\"WorkingDir\":\"\",\"Entrypoint\":null,\"NetworkDisabled\":false,\"MacAddress\":\"\",\"OnBuild\":[],\"SecurityOpt\":null,\"Labels\":null},\"architecture\":\"amd64\",\"os\":\"linux\",\"Size\":0}\n" 142 }, 143 ], 144 "schemaVersion": 1, 145 "signatures": [ 146 { 147 "header": { 148 "jwk": { 149 "crv": "P-256", 150 "kid": "OD6I:6DRK:JXEJ:KBM4:255X:NSAA:MUSF:E4VM:ZI6W:CUN2:L4Z6:LSF4", 151 "kty": "EC", 152 "x": "3gAwX48IQ5oaYQAYSxor6rYYc_6yjuLCjtQ9LUakg4A", 153 "y": "t72ge6kIA1XOjqjVoEOiPPAURltJFBMGDSQvEGVB010" 154 }, 155 "alg": "ES256" 156 }, 157 "signature": "XREm0L8WNn27Ga_iE_vRnTxVMhhYY0Zst_FfkKopg6gWSoTOZTuW4rK0fg_IqnKkEKlbD83tD46LKEGi5aIVFg", 158 "protected": "eyJmb3JtYXRMZW5ndGgiOjY2MjgsImZvcm1hdFRhaWwiOiJDbjAiLCJ0aW1lIjoiMjAxNS0wNC0wOFQxODo1Mjo1OVoifQ" 159 } 160 ] 161 } 162 163 ```