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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
JsonSchemaValidator:
});
/**
* Base class for local actions.
*
* This should be subclassed. Subclasses must implement _run() for
* per-recipe behavior, and may implement _preExecution and _finalize
* for actions to be taken once before and after recipes are run.
*
* Other methods should be overridden with care, to maintain the life
* cycle events and error reporting implemented by this class.
*/
export class BaseAction {
constructor() {
this.state = BaseAction.STATE_PREPARING;
this.log = lazy.LogManager.getLogger(`action.${this.name}`);
this.lastError = null;
}
/**
* Be sure to run the _preExecution() hook once during its
* lifecycle.
*
* This is not intended for overriding by subclasses.
*/
_ensurePreExecution() {
if (this.state !== BaseAction.STATE_PREPARING) {
return;
}
try {
this._preExecution();
// if _preExecution changed the state, don't overwrite it
if (this.state === BaseAction.STATE_PREPARING) {
this.state = BaseAction.STATE_READY;
}
} catch (err) {
// Sometimes err.message is editable. If it is, add helpful details.
// Otherwise log the helpful details and move on.
try {
err.message = `Could not initialize action ${this.name}: ${err.message}`;
} catch (_e) {
this.log.error(
`Could not initialize action ${this.name}, error follows.`
);
}
this.fail(err);
}
}
get schema() {
return {
type: "object",
properties: {},
};
}
/**
* Disable the action for a non-error reason, such as the user opting out of
* this type of action.
*/
disable() {
this.state = BaseAction.STATE_DISABLED;
}
fail(err) {
switch (this.state) {
case BaseAction.STATE_PREPARING: {
Uptake.reportAction(this.name, Uptake.ACTION_PRE_EXECUTION_ERROR);
break;
}
default: {
console.error(new Error("BaseAction.fail() called at unexpected time"));
}
}
this.state = BaseAction.STATE_FAILED;
this.lastError = err;
console.error(err);
}
// Gets the name of the action. Does not necessarily match the
// server slug for the action.
get name() {
return this.constructor.name;
}
/**
* Action specific pre-execution behavior should be implemented
* here. It will be called once per execution session.
*/
_preExecution() {
// Does nothing, may be overridden
}
validateArguments(args, schema = this.schema) {
let { valid, parsedValue: validated } = lazy.JsonSchemaValidator.validate(
args,
schema,
{
allowAdditionalProperties: true,
}
);
if (!valid) {
throw new Error(
`Arguments do not match schema. arguments:\n${JSON.stringify(args)}\n` +
`schema:\n${JSON.stringify(schema)}`
);
}
return validated;
}
/**
* Execute the per-recipe behavior of this action for a given
* recipe. Reports Uptake telemetry for the execution of the recipe.
*
* @param {Recipe} recipe
* @param {BaseAction.suitability} suitability
* @throws If this action has already been finalized.
*/
async processRecipe(recipe, suitability) {
if (!BaseAction.suitabilitySet.has(suitability)) {
throw new Error(`Unknown recipe status ${suitability}`);
}
this._ensurePreExecution();
if (this.state === BaseAction.STATE_FINALIZED) {
throw new Error("Action has already been finalized");
}
if (this.state !== BaseAction.STATE_READY) {
Uptake.reportRecipe(recipe, Uptake.RECIPE_ACTION_DISABLED);
this.log.warn(
`Skipping recipe ${recipe.name} because ${this.name} was disabled during preExecution.`
);
return;
}
let uptakeResult = BaseAction.suitabilityToUptakeStatus[suitability];
if (!uptakeResult) {
throw new Error(
`Coding error, no uptake status for suitability ${suitability}`
);
}
// If capabilties don't match, we can't even be sure that the arguments
// should be valid. In that case don't try to validate them.
if (suitability !== BaseAction.suitability.CAPABILITIES_MISMATCH) {
try {
recipe.arguments = this.validateArguments(recipe.arguments);
} catch (error) {
console.error(error);
uptakeResult = Uptake.RECIPE_EXECUTION_ERROR;
suitability = BaseAction.suitability.ARGUMENTS_INVALID;
}
}
try {
await this._processRecipe(recipe, suitability);
} catch (err) {
console.error(err);
uptakeResult = Uptake.RECIPE_EXECUTION_ERROR;
}
Uptake.reportRecipe(recipe, uptakeResult);
}
/**
* Action specific recipe behavior may be implemented here. It will be
* executed once for each recipe that applies to this client.
* The recipe will be passed as a parameter.
*
* @param {Recipe} recipe
*/
async _run() {
throw new Error("Not implemented");
}
/**
* Action specific recipe behavior should be implemented here. It will be
* executed once for every recipe currently published. The suitability of the
* recipe will be passed, it will be one of the constants from
* `BaseAction.suitability`.
*
* By default, this calls `_run()` for recipes with `status == FILTER_MATCH`,
* and does nothing for all other recipes. It is invalid for an action to
* override both `_run` and `_processRecipe`.
*
* @param {Recipe} recipe
* @param {RecipeSuitability} suitability
*/
async _processRecipe(recipe, suitability) {
if (!suitability) {
throw new Error("Suitability is undefined:", suitability);
}
if (suitability == BaseAction.suitability.FILTER_MATCH) {
await this._run(recipe);
}
}
/**
* Finish an execution session. After this method is called, no
* other methods may be called on this method, and all relevant
* recipes will be assumed to have been seen.
*/
async finalize(options) {
// It's possible that no recipes used this action, so processRecipe()
// was never called. In that case, we should ensure that we call
// _preExecute() here.
this._ensurePreExecution();
let status;
switch (this.state) {
case BaseAction.STATE_FINALIZED: {
throw new Error("Action has already been finalized");
}
case BaseAction.STATE_READY: {
try {
await this._finalize(options);
status = Uptake.ACTION_SUCCESS;
} catch (err) {
status = Uptake.ACTION_POST_EXECUTION_ERROR;
// Sometimes Error.message can be updated in place. This gives better messages when debugging errors.
try {
err.message = `Could not run postExecution hook for ${this.name}: ${err.message}`;
} catch (err) {
// Sometimes Error.message cannot be updated. Log a warning, and move on.
this.log.debug(`Could not run postExecution hook for ${this.name}`);
}
this.lastError = err;
console.error(err);
}
break;
}
case BaseAction.STATE_DISABLED: {
this.log.debug(
`Skipping post-execution hook for ${this.name} because it is disabled.`
);
status = Uptake.ACTION_SUCCESS;
break;
}
case BaseAction.STATE_FAILED: {
this.log.debug(
`Skipping post-execution hook for ${this.name} because it failed during pre-execution.`
);
// Don't report a status. A status should have already been reported by this.fail().
break;
}
default: {
throw new Error(`Unexpected state during finalize: ${this.state}`);
}
}
this.state = BaseAction.STATE_FINALIZED;
if (status) {
Uptake.reportAction(this.name, status);
}
}
/**
* Action specific post-execution behavior should be implemented
* here. It will be executed once after all recipes have been
* processed.
*/
async _finalize(_options = {}) {
// Does nothing, may be overridden
}
}
BaseAction.STATE_PREPARING = "ACTION_PREPARING";
BaseAction.STATE_READY = "ACTION_READY";
BaseAction.STATE_DISABLED = "ACTION_DISABLED";
BaseAction.STATE_FAILED = "ACTION_FAILED";
BaseAction.STATE_FINALIZED = "ACTION_FINALIZED";
// Make sure to update the docs in ../docs/suitabilities.rst when changing this.
BaseAction.suitability = {
/**
* The recipe's signature is not valid. If any action is taken this recipe
* should be treated with extreme suspicion.
*/
SIGNATURE_ERROR: "RECIPE_SUITABILITY_SIGNATURE_ERROR",
/**
* The recipe requires capabilities that this recipe runner does not have.
* Use caution when interacting with this recipe, as it may not match the
* expected schema.
*/
CAPABILITIES_MISMATCH: "RECIPE_SUITABILITY_CAPABILITIES_MISMATCH",
/**
* The recipe is suitable to execute in this client.
*/
FILTER_MATCH: "RECIPE_SUITABILITY_FILTER_MATCH",
/**
* This client does not match the recipe's filter, but it is otherwise a
* suitable recipe.
*/
FILTER_MISMATCH: "RECIPE_SUITABILITY_FILTER_MISMATCH",
/**
* There was an error while evaluating the filter. It is unknown if this
* client matches this filter. This may be temporary, due to network errors,
* or permanent due to syntax errors.
*/
FILTER_ERROR: "RECIPE_SUITABILITY_FILTER_ERROR",
/**
* The arguments of the recipe do not match the expected schema for the named
* action.
*/
ARGUMENTS_INVALID: "RECIPE_SUITABILITY_ARGUMENTS_INVALID",
};
BaseAction.suitabilitySet = new Set(Object.values(BaseAction.suitability));
BaseAction.suitabilityToUptakeStatus = {
[BaseAction.suitability.SIGNATURE_ERROR]: Uptake.RECIPE_INVALID_SIGNATURE,
[BaseAction.suitability.CAPABILITIES_MISMATCH]:
Uptake.RECIPE_INCOMPATIBLE_CAPABILITIES,
[BaseAction.suitability.FILTER_MATCH]: Uptake.RECIPE_SUCCESS,
[BaseAction.suitability.FILTER_MISMATCH]: Uptake.RECIPE_DIDNT_MATCH_FILTER,
[BaseAction.suitability.FILTER_ERROR]: Uptake.RECIPE_FILTER_BROKEN,
[BaseAction.suitability.ARGUMENTS_INVALID]: Uptake.RECIPE_ARGUMENTS_INVALID,
};