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 ```