11 Commits (f-testing-eval-prototype)

Author	SHA1	Message	Date
James Bardin	292535820d	ResourceInstanceObject needs to return a copy	7 years ago
Sander van Harmelen	19c1241a50	command/state: update and fix the state rm command	8 years ago
Martin Atkins	66f96cf842	command: Un-stub and reimplement "terraform state rm" ... This was previously targeting the old state manager and state types, so it needed some considerable rework to get it working again with the new state types. Since our new resource address syntax lacks the weird extra .deposed special case we had before, we instead interpret addresses as whole-instance addresses here and remove the deposed objects along with the current one (if present), since this is more likely to match with user expectations because we don't consider deposed objects to be independently addressable in any other situation. With that said, to be more explicit about what is going on we do now have a -dry-run mode and maintain separate counts of current and deposed instances so that we can expose that in the UI where relevant.	8 years ago
Martin Atkins	2eea07750a	core: Clean up resource states when they are orphaned ... We previously had mechanisms to clean up only individual instance states, leaving behind empty resource husks in the state after they were all destroyed. This takes care of it in the "orphan" case. It does not yet do it in the "terraform destroy" or "terraform plan -destroy" cases because we don't have anywhere to record in the plan that we're actually destroying and so the resource configurations should be ignored and _everything_ should be cleaned. We'll let the state be not-quite-empty in that case for now, since it doesn't really hurt; cleaning up orphans is the main case because the state will live on afterwards and so leftover cruft will accumulate over the course of many changes.	8 years ago
Martin Atkins	faddb83a92	core: If create leg of create_before_destroy fails, restore deposed ... I misunderstood the logic here on the first pass of porting to the new provider and state types: EvalUndeposeState is supposed to return the deposed object back to being current again, so we can undo the deposing in the case where the create leg fails. If we don't do this, we end up leaving the instance with no current object at all and with its prior object deposed, and then the later destroy node deletes that deposed object, leaving the user with no object at all. For safety we skip this restoration if there _is_ a new current object, since a failed create can still produce a partial result which we need to keep to avoid losing track of any remote objects that were successfully created.	8 years ago
Martin Atkins	334c6f1c2c	core: Be more explicit in how we handle create_before_destroy ... Previously our handling of create_before_destroy -- and of deposed objects in particular -- was rather "implicit" and spread over various different subsystems. We'd quietly just destroy every deposed object during a destroy operation, without any user-visible plan to do so. Here we make things more explicit by tracking each deposed object individually by its pseudorandomly-allocated key. There are two different mechanisms at play here, building on the same concepts: - During a replace operation with create_before_destroy, we *pre-allocate* a DeposedKey to use for the prior object in the "apply" node and then pass that exact id to the destroy node, ensuring that we only destroy the single object we planned to destroy. In the happy path here the user never actually sees the allocated deposed key because we use it and then immediately destroy it within the same operation. However, that destroy may fail, which brings us to the second mechanism: - If any deposed objects are already present in state during _plan_, we insert a destroy change for them into the plan so that it's explicit to the user that we are going to destroy these additional objects, and then create an individual graph node for each one in DiffTransformer. The main motivation here is to be more careful in how we handle these destroys so that from a user's standpoint we never destroy something without the user knowing about it ahead of time. However, this new organization also hopefully makes the code itself a little easier to follow because the connection between the create and destroy steps of a Replace is reprseented in a single place (in DiffTransformer) and deposed instances each have their own explicit graph node rather than being secretly handled as part of the main instance-level graph node.	8 years ago
Martin Atkins	edc0ce6333	states: Prune empty modules after possibly removing resources ... Also includes a new log message for the situation where we _do_ prune, since this seems helpful during debugging.	8 years ago
Martin Atkins	9af67806fc	core: Prune placeholder objects from state after refresh ... Prior to our refactoring here, we were relying on a lucky coincidence for correct behavior of the plan walk following a refresh in the same run: - The refresh phase created placeholder objects in the state to represent any resource instance pending creation, to allow the interpolator to read attributes from them when evaluating "provider" and "data" blocks. In effect, the refresh walk is creating a partial plan that only covers creation actions, but was immediately discarding the actual diff entries and storing only the planned new state. - It happened that objects pending creation showed up in state with an empty ID value, since that only gets assigned by the provider during apply. - The Refresh function concluded by calling terraform.State.Prune, which deletes from the state any objects that have an empty ID value, which therefore prevented these temporary objects from surviving into the plan phase. After refactoring, we no longer have this special ID field on instance object state, and we instead rely on the Status field for tracking such things. We also no longer have an explicit "prune" step on state, since the state mutation methods themselves keep the structure pruned. To address this, here we introduce a new instance object status "planned", which is equivalent to having an empty ID value in the old world. We also introduce a new method on states.SyncState that deletes from the state any planned objects, which therefore replaces that portion of the old State.prune operation just for this refresh use-case. Finally, we are now expecting the expression evaluator to pull pending objects from the planned changeset rather than from the state directly, and so for correct results these placeholder resource creation changes must also be reported in a throwaway changeset during the refresh walk. The addition of states.ObjectPlanned also permits a previously-missing safety check in the expression evaluator to prevent us from relying on the incomplete value stored in state for a pending object, in the event that some bug prevents the real pending object from being written into the planned changeset.	8 years ago
Martin Atkins	a3403f2766	terraform: Ugly huge change to weave in new State and Plan types ... Due to how often the state and plan types are referenced throughout Terraform, there isn't a great way to switch them out gradually. As a consequence, this huge commit gets us from the old world to a _compilable_ new world, but still has a large number of known test failures due to key functionality being stubbed out. The stubs here are for anything that interacts with providers, since we now need to do the follow-up work to similarly replace the old terraform.ResourceProvider interface with its replacement in the new "providers" package. That work, along with work to fix the remaining failing tests, will follow in subsequent commits. The aim here was to replace all references to terraform.State and its downstream types with states.State, terraform.Plan with plans.Plan, state.State with statemgr.State, and switch to the new implementations of the state and plan file formats. However, due to the number of times those types are used, this also ended up affecting numerous other parts of core such as terraform.Hook, the backend.Backend interface, and most of the CLI commands. Just as with 5861dbf3fc before, I apologize in advance to the person who inevitably just found this huge commit while spelunking through the commit history.	8 years ago
Martin Atkins	424afe0ace	states: separate types for encoded and decoded state objects ... The types here were originally written to allow us to defer decoding of object values until schemas are available, but it turns out that this was forcing us to defer decoding longer than necessary and potentially decode the same value multiple times. To avoid this, we create pairs of types to represent the encoded and decoded versions and methods for moving between them. These types are identical to one another apart from how the dynamic values are represented.	8 years ago
Martin Atkins	a33f941778	states: New SyncState type ... This is a wrapper around State that is able to perform higher-level manipulations (at the granularity of the entire state) in a concurrency-safe manner, using the lower-level APIs exposed by State and all of the types it contains. The granularity of a SyncState operation roughly matches the granularity off a state-related EvalNode in the "terraform" package, performing a sequence of more primitive operations while guaranteeing atomicity of the entire change. As a compromise for convenience of usage, it's still possible to access the individual state data objects via this API, but they are always copied before returning to ensure that two distinct callers cannot have data races. Callers should access the most granular object possible for their operation.	8 years ago