github.com/muratcelep/terraform@v1.1.0-beta2-not-internal-4/website/docs/internals/json-format.html.md (about)

     1  ---
     2  layout: "docs"
     3  page_title: "Internals: JSON Output Format"
     4  sidebar_current: "docs-internals-json"
     5  description: |-
     6    Terraform provides a machine-readable JSON representation of state, configuration and plan.
     7  ---
     8  
     9  # JSON Output Format
    10  
    11  -> **Note:** This format is available in Terraform 0.12 and later.
    12  
    13  When Terraform plans to make changes, it prints a human-readable summary to the terminal. It can also, when run with `-out=<PATH>`, write a much more detailed binary plan file, which can later be used to apply those changes.
    14  
    15  Since the format of plan files isn't suited for use with external tools (and likely never will be), Terraform can output a machine-readable JSON representation of a plan file's changes. It can also convert state files to the same format, to simplify data loading and provide better long-term compatibility.
    16  
    17  Use `terraform show -json <FILE>` to generate a JSON representation of a plan or state file. See [the `terraform show` documentation](/docs/cli/commands/show.html) for more details.
    18  
    19  The output includes a `format_version` key, which as of Terraform 1.1.0 has
    20  value `"1.0"`. The semantics of this version are:
    21  
    22  - We will increment the minor version, e.g. `"1.1"`, for backward-compatible
    23    changes or additions. Ignore any object properties with unrecognized names to
    24    remain forward-compatible with future minor versions.
    25  - We will increment the major version, e.g. `"2.0"`, for changes that are not
    26    backward-compatible. Reject any input which reports an unsupported major
    27    version.
    28  
    29  We will introduce new major versions only within the bounds of
    30  [the Terraform 1.0 Compatibility Promises](https://www.terraform.io/docs/language/v1-compatibility-promises.html).
    31  
    32  ## Format Summary
    33  
    34  The following sections describe the JSON output format by example, using a pseudo-JSON notation.
    35  
    36  Important elements are described with comments, which are prefixed with `//`.
    37  
    38  To avoid excessive repetition, we've split the complete format into several discrete sub-objects, described under separate headers. References wrapped in angle brackets (like `<values-representation>`) are placeholders which, in the real output, would be replaced by an instance of the specified sub-object.
    39  
    40  The JSON output format consists of the following objects and sub-objects:
    41  
    42  - [State Representation](#state-representation) — The complete top-level object returned by `terraform show -json <STATE FILE>`.
    43  - [Plan Representation](#plan-representation) — The complete top-level object returned by `terraform show -json <PLAN FILE>`.
    44  - [Values Representation](#values-representation) — A sub-object of both plan and state output that describes current state or planned state.
    45  - [Configuration Representation](#configuration-representation) — A sub-object of plan output that describes a parsed Terraform configuration.
    46      - [Expression Representation](#expression-representation) — A sub-object of a configuration representation that describes an unevaluated expression.
    47      - [Block Expressions Representation](#block-expressions-representation) — A sub-object of a configuration representation that describes the expressions nested inside a block.
    48  - [Change Representation](#change-representation) — A sub-object of plan output that describes planned changes to an object.
    49  
    50  ## State Representation
    51  
    52  Because state does not currently have any significant metadata not covered by the common values representation ([described below](#values-representation)), the `<state-representation>` is straightforward:
    53  
    54  ```javascript
    55  {
    56    // "values" is a values representation object derived from the values in the
    57    // state. Because the state is always fully known, this is always complete.
    58    "values": <values-representation>
    59  
    60    "terraform_version": "version.string"
    61  }
    62  ```
    63  
    64  The extra wrapping object here will allow for any extension we may need to add in future versions of this format.
    65  
    66  ## Plan Representation
    67  
    68  A plan consists of a prior state, the configuration that is being applied to that state, and the set of changes Terraform plans to make to achieve that.
    69  
    70  For ease of consumption by callers, the plan representation includes a partial representation of the values in the final state (using a [value representation](#values-representation)), allowing callers to easily analyze the planned outcome using similar code as for analyzing the prior state.
    71  
    72  ```javascript
    73  {
    74    "format_version": "1.0",
    75  
    76    // "prior_state" is a representation of the state that the configuration is
    77    // being applied to, using the state representation described above.
    78    "prior_state":  <state-representation>,
    79  
    80    // "configuration" is a representation of the configuration being applied to the
    81    // prior state, using the configuration representation described above.
    82    "configuration": <configuration-representation>,
    83  
    84    // "planned_values" is a description of what is known so far of the outcome in
    85    // the standard value representation, with any as-yet-unknown values omitted.
    86    "planned_values": <values-representation>,
    87  
    88    // "proposed_unknown" is a representation of the attributes, including any
    89    // potentially-unknown attributes. Each value is replaced with "true" or
    90    // "false" depending on whether it is known in the proposed plan.
    91    "proposed_unknown": <values-representation>,
    92  
    93    // "variables" is a representation of all the variables provided for the given
    94    // plan. This is structured as a map similar to the output map so we can add
    95    // additional fields in later.
    96    "variables": {
    97      "varname": {
    98        "value": "varvalue"
    99      },
   100    },
   101  
   102    // "changes" is a description of the individual change actions that Terraform
   103    // plans to use to move from the prior state to a new state matching the
   104    // configuration.
   105    "resource_changes": [
   106      // Each element of this array describes the action to take
   107      // for one instance object. All resources in the
   108      // configuration are included in this list.
   109      {
   110        // "address" is the full absolute address of the resource instance this
   111        // change applies to, in the same format as addresses in a value
   112        // representation.
   113        "address": "module.child.aws_instance.foo[0]",
   114  
   115        // "previous_address" is the full absolute address of this resource
   116        // instance as it was known after the previous Terraform run.
   117        // Included only if the address has changed, e.g. by handling
   118        // a "moved" block in the configuration.
   119        "previous_address": "module.instances.aws_instance.foo[0]",
   120  
   121        // "module_address", if set, is the module portion of the above address.
   122        // Omitted if the instance is in the root module.
   123        "module_address": "module.child",
   124  
   125        // "mode", "type", "name", and "index" have the same meaning as in a
   126        // value representation.
   127        "mode": "managed",
   128        "type": "aws_instance",
   129        "name": "foo",
   130        "index": 0,
   131  
   132        // "deposed", if set, indicates that this action applies to a "deposed"
   133        // object of the given instance rather than to its "current" object.
   134        // Omitted for changes to the current object. "address" and "deposed"
   135        // together form a unique key across all change objects in a particular
   136        // plan. The value is an opaque key representing the specific deposed
   137        // object.
   138        "deposed": "deadbeef",
   139  
   140        // "change" describes the change that will be made to the indicated
   141        // object. The <change-representation> is detailed in a section below.
   142        "change": <change-representation>,
   143  
   144        // "action_reason" is some optional extra context about why the
   145        // actions given inside "change" were selected. This is the JSON
   146        // equivalent of annotations shown in the normal plan output like
   147        // "is tainted, so must be replaced" as opposed to just "must be
   148        // replaced".
   149        //
   150        // These reason codes are display hints only and the set of possible
   151        // hints may change over time. Users of this must be prepared to
   152        // encounter unrecognized reasons and treat them as unspecified reasons.
   153        //
   154        // The current set of possible values is:
   155        // - "replace_because_tainted": the object in question is marked as
   156        //   "tainted" in the prior state, so Terraform planned to replace it.
   157        // - "replace_because_cannot_update": the provider indicated that one
   158        //   of the requested changes isn't possible without replacing the
   159        //   existing object with a new object.
   160        // - "replace_by_request": the user explicitly called for this object
   161        //   to be replaced as an option when creating the plan, which therefore
   162        //   overrode what would have been a "no-op" or "update" action otherwise.
   163        // - "delete_because_no_resource_config": Terraform found no resource
   164        //   configuration corresponding to this instance.
   165        // - "delete_because_no_module": The resource instance belongs to a
   166        //   module instance that's no longer declared, perhaps due to changing
   167        //   the "count" or "for_each" argument on one of the containing modules.
   168        // - "delete_because_wrong_repetition": The instance key portion of the
   169        //   resource address isn't of a suitable type for the corresponding
   170        //   resource's configured repetition mode (count, for_each, or neither).
   171        // - "delete_because_count_index": The corresponding resource uses count,
   172        //   but the instance key is out of range for the currently-configured
   173        //   count value.
   174        // - "delete_because_each_key": The corresponding resource uses for_each,
   175        //   but the instance key doesn't match any of the keys in the
   176        //   currently-configured for_each value.
   177        //
   178        // If there is no special reason to note, Terraform will omit this
   179        // property altogether.
   180        action_reason: "replace_because_tainted"
   181      }
   182    ],
   183  
   184    // "output_changes" describes the planned changes to the output values of the
   185    // root module.
   186    "output_changes": {
   187      // Keys are the defined output value names.
   188      "foo": {
   189  
   190        // "change" describes the change that will be made to the indicated output
   191        // value, using the same representation as for resource changes except
   192        // that the only valid actions values are:
   193        //   ["create"]
   194        //   ["update"]
   195        //   ["delete"]
   196        // In the Terraform CLI 0.12.0 release, Terraform is not yet fully able to
   197        // track changes to output values, so the actions indicated may not be
   198        // fully accurate, but the "after" value will always be correct.
   199        "change": <change-representation>,
   200      }
   201    }
   202  }
   203  ```
   204  
   205  This overall plan structure, fully expanded, is what will be printed by the `terraform show -json <planfile>` command.
   206  
   207  ## Values Representation
   208  
   209  A values representation is used in both state and plan output to describe current state (which is always complete) and planned state (which omits values not known until apply).
   210  
   211  The following example illustrates the structure of a `<values-representation>`:
   212  
   213  ```javascript
   214  {
   215    // "outputs" describes the outputs from the root module. Outputs from
   216    // descendent modules are not available because they are not retained in all
   217    // of the underlying structures we will build this values representation from.
   218    "outputs": {
   219      "private_ip": {
   220        "value": "192.168.3.2",
   221        "sensitive": false
   222      }
   223    },
   224  
   225    // "root_module" describes the resources and child modules in the root module.
   226    "root_module": {
   227      "resources": [
   228        {
   229          // "address" is the absolute resource address, which callers must consider
   230          // opaque but may do full string comparisons with other address strings or
   231          // pass this verbatim to other Terraform commands that are documented to
   232          // accept absolute resource addresses. The module-local portions of this
   233          // address are extracted in other properties below.
   234          "address": "aws_instance.example[1]",
   235  
   236          // "mode" can be "managed", for resources, or "data", for data resources
   237          "mode": "managed",
   238          "type": "aws_instance",
   239          "name": "example",
   240  
   241          // If the count or for_each meta-arguments are set for this resource, the
   242          // additional key "index" is present to give the instance index key. This
   243          // is omitted for the single instance of a resource that isn't using count
   244          // or for_each.
   245          "index": 1,
   246  
   247          // "provider_name" is the name of the provider that is responsible for
   248          // this resource. This is only the provider name, not a provider
   249          // configuration address, and so no module path nor alias will be
   250          // indicated here. This is included to allow the property "type" to be
   251          // interpreted unambiguously in the unusual situation where a provider
   252          // offers a resource type whose name does not start with its own name,
   253          // such as the "googlebeta" provider offering "google_compute_instance".
   254          "provider_name": "aws",
   255  
   256          // "schema_version" indicates which version of the resource type schema
   257          // the "values" property conforms to.
   258          "schema_version": 2,
   259  
   260          // "values" is the JSON representation of the attribute values of the
   261          // resource, whose structure depends on the resource type schema. Any
   262          // unknown values are omitted or set to null, making them
   263          // indistinguishable from absent values; callers which need to distinguish
   264          // unknown from unset must use the plan-specific or configuration-specific
   265          // structures described in later sections.
   266          "values": {
   267            "id": "i-abc123",
   268            "instance_type": "t2.micro",
   269            // etc, etc
   270          },
   271  
   272          // "sensitive_values" is the JSON representation of the sensitivity of
   273          // the resource's attribute values. Only attributes which are sensitive
   274          // are included in this structure.
   275          "values": {
   276            "id": true,
   277          }
   278        }
   279      ]
   280  
   281      "child_modules": [
   282        // Each entry in "child_modules" has the same structure as the root_module
   283        // object, with the additional "address" property shown below.
   284        {
   285          // "address" is the absolute module address, which callers must treat as
   286          // opaque but may do full string comparisons with other module address
   287          // strings and may pass verbatim to other Terraform commands that are
   288          // documented as accepting absolute module addresses.
   289          "address": "module.child",
   290  
   291          // "resources" is the same as in "root_module" above
   292          "resources": [
   293              {
   294                "address": "module.child.aws_instance.foo",
   295                // etc, etc
   296              }
   297          ],
   298  
   299          // Each module object can optionally have its own
   300          // nested "child_modules", recursively describing the
   301          // full module tree.
   302          "child_modules": [ ... ],
   303        }
   304      ]
   305    }
   306  }
   307  ```
   308  
   309  The translation of attribute and output values is the same intuitive mapping from HCL types to JSON types used by Terraform's [`jsonencode`](/docs/language/functions/jsonencode.html) function. This mapping does lose some information: lists, sets, and tuples all lower to JSON arrays while maps and objects both lower to JSON objects. Unknown values and null values are both treated as absent or null.
   310  
   311  Only the "current" object for each resource instance is described. "Deposed" objects are not reflected in this structure at all; in plan representations, you can refer to the change representations for further details.
   312  
   313  The intent of this structure is to give a caller access to a similar level of detail as is available to expressions within the configuration itself. This common representation is not suitable for all use-cases because it loses information compared to the data structures it is built from. For more complex needs, use the more elaborate changes and configuration representations.
   314  
   315  ## Configuration Representation
   316  
   317  Configuration is the most complicated structure in Terraform, since it includes unevaluated expression nodes and other complexities.
   318  
   319  Because the configuration models are produced at a stage prior to expression evaluation, it is not possible to produce a values representation for configuration. Instead, we describe the physical structure of the configuration, giving access to constant values where possible and allowing callers to analyze any references to other objects that are present:
   320  
   321  ```javascript
   322  {
   323    // "provider_configs" describes all of the provider configurations throughout
   324    // the configuration tree, flattened into a single map for convenience since
   325    // provider configurations are the one concept in Terraform that can span
   326    // across module boundaries.
   327    "provider_configs": {
   328  
   329      // Keys in the provider_configs map are to be considered opaque by callers,
   330      // and used just for lookups using the "provider_config_key" property in each
   331      // resource object.
   332      "opaque_provider_ref_aws": {
   333  
   334        // "name" is the name of the provider without any alias
   335        "name": "aws",
   336  
   337        // "alias" is the alias set for a non-default configuration, or unset for
   338        // a default configuration.
   339        "alias": "foo",
   340  
   341        // "module_address" is included only for provider configurations that are
   342        // declared in a descendent module, and gives the opaque address for the
   343        // module that contains the provider configuration.
   344        "module_address": "module.child",
   345  
   346        // "expressions" describes the provider-specific content of the
   347        // configuration block, as a block expressions representation (see section
   348        // below).
   349        "expressions": <block-expressions-representation>
   350      }
   351    },
   352  
   353    // "root_module" describes the root module in the configuration, and serves
   354    // as the root of a tree of similar objects describing descendent modules.
   355    "root_module": {
   356  
   357      // "outputs" describes the output value configurations in the module.
   358      "outputs": {
   359  
   360        // Property names here are the output value names
   361        "example": {
   362          "expression": <expression-representation>,
   363          "sensitive": false
   364        }
   365      },
   366  
   367      // "resources" describes the "resource" and "data" blocks in the module
   368      // configuration.
   369      "resources": [
   370        {
   371          // "address" is the opaque absolute address for the resource itself.
   372          "address": "aws_instance.example",
   373  
   374          // "mode", "type", and "name" have the same meaning as for the resource
   375          // portion of a value representation.
   376          "mode": "managed",
   377          "type": "aws_instance",
   378          "name": "example",
   379  
   380          // "provider_config_key" is the key into "provider_configs" (shown
   381          // above) for the provider configuration that this resource is
   382          // associated with.
   383          "provider_config_key": "opaque_provider_ref_aws",
   384  
   385          // "provisioners" is an optional field which describes any provisioners.
   386          // Connection info will not be included here.
   387          "provisioners": [
   388            {
   389              "type": "local-exec",
   390  
   391              // "expressions" describes the provisioner configuration
   392              "expressions": <block-expressions-representation>
   393            },
   394          ],
   395  
   396          // "expressions" describes the resource-type-specific content of the
   397          // configuration block.
   398          "expressions": <block-expressions-representation>,
   399  
   400          // "schema_version" is the schema version number indicated by the
   401          // provider for the type-specific arguments described in "expressions".
   402          "schema_version": 2,
   403  
   404          // "count_expression" and "for_each_expression" describe the expressions
   405          // given for the corresponding meta-arguments in the resource
   406          // configuration block. These are omitted if the corresponding argument
   407          // isn't set.
   408          "count_expression": <expression-representation>,
   409          "for_each_expression": <expression-representation>
   410        },
   411      ],
   412  
   413      // "module_calls" describes the "module" blocks in the module. During
   414      // evaluation, a module call with count or for_each may expand to multiple
   415      // module instances, but in configuration only the block itself is
   416      // represented.
   417      "module_calls": {
   418  
   419        // Key is the module call name chosen in the configuration.
   420        "child": {
   421  
   422          // "resolved_source" is the resolved source address of the module, after
   423          // any normalization and expansion. This could be either a
   424          // go-getter-style source address or a local path starting with "./" or
   425          // "../". If the user gave a registry source address then this is the
   426          // final location of the module as returned by the registry, after
   427          // following any redirect indirection.
   428          "resolved_source": "./child"
   429  
   430          // "expressions" describes the expressions for the arguments within the
   431          // block that correspond to input variables in the child module.
   432          "expressions": <block-expressions-representation>,
   433  
   434          // "count_expression" and "for_each_expression" describe the expressions
   435          // given for the corresponding meta-arguments in the module
   436          // configuration block. These are omitted if the corresponding argument
   437          // isn't set.
   438          "count_expression": <expression-representation>,
   439          "for_each_expression": <expression-representation>,
   440  
   441          // "module" is a representation of the configuration of the child module
   442          // itself, using the same structure as the "root_module" object,
   443          // recursively describing the full module tree.
   444          "module": <module-configuration-representation>,
   445        }
   446      }
   447    }
   448  }
   449  ```
   450  
   451  ### Expression Representation
   452  
   453  Each unevaluated expression in the configuration is represented with an `<expression-representation>` object with the following structure:
   454  
   455  ```javascript
   456  {
   457    // "constant_value" is set only if the expression contains no references to
   458    // other objects, in which case it gives the resulting constant value. This is
   459    // mapped as for the individual values in a value representation.
   460    "constant_value": "hello",
   461  
   462    // Alternatively, "references" will be set to a list of references in the
   463    // expression. Multi-step references will be unwrapped and duplicated for each
   464    // significant traversal step, allowing callers to more easily recognize the
   465    // objects they care about without attempting to parse the expressions.
   466    // Callers should only use string equality checks here, since the syntax may
   467    // be extended in future releases.
   468    "references": [
   469      "data.template_file.foo[1].vars[\"baz\"]",
   470      "data.template_file.foo[1].vars", // implied by previous
   471      "data.template_file.foo[1]", // implied by previous
   472      "data.template_file.foo", // implied by previous
   473      "module.foo.bar",
   474      "module.foo", // implied by the previous
   475      "var.example[0]",
   476      "var.example", // implied by the previous
   477  
   478      // Partial references like "data" and "module" are not included, because
   479      // Terraform considers "module.foo" to be an atomic reference, not an
   480      // attribute access.
   481    ]
   482  }
   483  ```
   484  
   485  -> **Note:** Expressions in `dynamic` blocks are not included in the configuration representation.
   486  
   487  ### Block Expressions Representation
   488  
   489  In some cases, it is the entire content of a block (possibly after certain special arguments have already been handled and removed) that must be represented. For that, we have an `<block-expressions-representation>` structure:
   490  
   491  ```javascript
   492  {
   493    // Attribute arguments are mapped directly with the attribute name as key and
   494    // an <expression-representation> as value.
   495    "ami": <expression-representation>,
   496    "instance_type": <expression-representation>,
   497  
   498    // Nested block arguments are mapped as either a single nested
   499    // <block-expressions-representation> or an array object of these, depending on the
   500    // block nesting mode chosen in the schema.
   501    //  - "single" nesting is a direct <block-expressions-representation>
   502    //  - "list" and "set" produce arrays
   503    //  - "map" produces an object
   504    "root_block_device": <expression-representation>,
   505    "ebs_block_device": [
   506      <expression-representation>
   507    ]
   508  }
   509  ```
   510  
   511  For now we expect callers to just hard-code assumptions about the schemas of particular resource types in order to process these expression representations. In a later release we will add new inspection commands to return machine-readable descriptions of the schemas themselves, allowing for more generic handling in programs such as visualization tools.
   512  
   513  ## Change Representation
   514  
   515  A `<change-representation>` describes the change that will be made to the indicated object.
   516  
   517  ```javascript
   518  {
   519    // "actions" are the actions that will be taken on the object selected by the
   520    // properties below.
   521    // Valid actions values are:
   522    //    ["no-op"]
   523    //    ["create"]
   524    //    ["read"]
   525    //    ["update"]
   526    //    ["delete", "create"]
   527    //    ["create", "delete"]
   528    //    ["delete"]
   529    // The two "replace" actions are represented in this way to allow callers to
   530    // e.g. just scan the list for "delete" to recognize all three situations
   531    // where the object will be deleted, allowing for any new deletion
   532    // combinations that might be added in future.
   533    "actions": ["update"],
   534  
   535    // "before" and "after" are representations of the object value both before
   536    // and after the action. For ["create"] and ["delete"] actions, either
   537    // "before" or "after" is unset (respectively). For ["no-op"], the before and
   538    // after values are identical. The "after" value will be incomplete if there
   539    // are values within it that won't be known until after apply.
   540    "before": <value-representation>,
   541    "after": <value-representation>,
   542  
   543    // "after_unknown" is an object value with similar structure to "after", but
   544    // with all unknown leaf values replaced with "true", and all known leaf
   545    // values omitted. This can be combined with "after" to reconstruct a full
   546    // value after the action, including values which will only be known after
   547    // apply.
   548    "after_unknown": {
   549      "id": true
   550    },
   551  
   552    // "before_sensitive" and "after_sensitive" are object values with similar
   553    // structure to "before" and "after", but with all sensitive leaf values
   554    // replaced with true, and all non-sensitive leaf values omitted. These
   555    // objects should be combined with "before" and "after" to prevent accidental
   556    // display of sensitive values in user interfaces.
   557    "before_sensitive": {},
   558    "after_sensitive": {
   559      "triggers": {
   560        "boop": true
   561      }
   562    },
   563  
   564    // "replace_paths" is an array of arrays representing a set of paths into the
   565    // object value which resulted in the action being "replace". This will be
   566    // omitted if the action is not replace, or if no paths caused the
   567    // replacement (for example, if the resource was tainted). Each path
   568    // consists of one or more steps, each of which will be a number or a
   569    // string.
   570    "replace_paths": [["triggers"]]
   571  }
   572  ```