Files
mongo/jstests/core/command_let_variables.js
2020-06-11 18:22:47 +00:00

312 lines
12 KiB
JavaScript

// Tests that commands like find, aggregate and update accepts a 'let' parameter which defines
// variables for use in expressions within the command.
// @tags: [requires_fcv_46]
//
(function() {
"use strict";
load("jstests/libs/fixture_helpers.js"); // For 'isMongos' and 'isSharded'.
const testDB = db.getSiblingDB("command_let_variables");
const coll = testDB.command_let_variables;
const targetColl = testDB.command_let_variables_target;
assert.commandWorked(testDB.dropDatabase());
const testDocs = [
{
_id: 1,
Species: "Blackbird (Turdus merula)",
population_trends: [
{term: {start: 1970, end: 2014}, pct_change: -16, annual: -0.38, trend: "no change"},
{term: {start: 2009, end: 2014}, pct_change: -2, annual: -0.36, trend: "no change"}
]
},
{
_id: 2,
Species: "Bullfinch (Pyrrhula pyrrhula)",
population_trends: [
{term: {start: 1970, end: 2014}, pct_change: -39, annual: -1.13, trend: "no change"},
{term: {start: 2009, end: 2014}, pct_change: 12, annual: 2.38, trend: "weak increase"}
]
},
{
_id: 3,
Species: "Chaffinch (Fringilla coelebs)",
population_trends: [
{term: {start: 1970, end: 2014}, pct_change: 27, annual: 0.55, trend: "no change"},
{term: {start: 2009, end: 2014}, pct_change: -7, annual: -1.49, trend: "weak decline"}
]
},
{
_id: 4,
Species: "Song Thrush (Turdus philomelos)",
population_trends: [
{term: {start: 1970, end: 2014}, pct_change: -53, annual: -1.7, trend: "weak decline"},
{term: {start: 2009, end: 2014}, pct_change: -4, annual: -0.88, trend: "no change"}
]
}
];
assert.commandWorked(coll.insert(testDocs));
// Aggregate tests
const pipeline = [
{$project: {_id: 0}},
{$unwind: "$population_trends"},
{$match: {$expr: {$eq: ["$population_trends.trend", "$$target_trend"]}}},
{$sort: {Species: 1}}
];
let expectedResults = [{
Species: "Bullfinch (Pyrrhula pyrrhula)",
population_trends:
{term: {start: 2009, end: 2014}, pct_change: 12, annual: 2.38, trend: "weak increase"}
}];
assert.eq(coll.aggregate(pipeline, {let : {target_trend: "weak increase"}}).toArray(),
expectedResults);
expectedResults = [
{
Species: "Chaffinch (Fringilla coelebs)",
population_trends:
{term: {start: 2009, end: 2014}, pct_change: -7, annual: -1.49, trend: "weak decline"}
},
{
Species: "Song Thrush (Turdus philomelos)",
population_trends:
{term: {start: 1970, end: 2014}, pct_change: -53, annual: -1.7, trend: "weak decline"}
}
];
assert.eq(coll.aggregate(pipeline, {let : {target_trend: "weak decline"}}).toArray(),
expectedResults);
if (!FixtureHelpers.isMongos(testDB)) {
// Test that if runtimeConstants and let are both specified, both will coexist.
// Runtime constants are not allowed on mongos passthroughs.
let constants = {
localNow: new Date(),
clusterTime: new Timestamp(0, 0),
};
assert.eq(coll.aggregate(pipeline,
{runtimeConstants: constants, let : {target_trend: "weak decline"}})
.toArray(),
expectedResults);
// Test that undefined let params in the pipeline fail gracefully.
assert.commandFailedWithCode(testDB.runCommand({
aggregate: coll.getName(),
pipeline: pipeline,
runtimeConstants: constants,
cursor: {},
let : {cat: "not_a_bird"}
}),
17276);
// Test null and empty let parameters
const pipeline_no_lets = [
{$project: {_id: 0}},
{$unwind: "$population_trends"},
{$match: {$expr: {$eq: ["$population_trends.trend", "weak decline"]}}},
{$sort: {Species: 1}}
];
assert.eq(coll.aggregate(pipeline_no_lets, {runtimeConstants: constants, let : {}}).toArray(),
expectedResults);
assert.commandFailedWithCode(testDB.runCommand({
aggregate: coll.getName(),
pipeline: pipeline_no_lets,
runtimeConstants: constants,
cursor: {},
let : null
}),
ErrorCodes.TypeMismatch);
}
// Test that $project stage can use 'let' variables
assert.eq(testDB
.runCommand({
aggregate: coll.getName(),
pipeline: [
{
$project: {
"var": {
$let: {
vars: {variable: "INNER"},
"in": {
$cond: {
"if": {$eq: [{$substr: ["$Species", 0, 1]}, "B"]},
then: "$$variable",
"else": "---"
}
}
}
}
}
},
{$match: {$expr: {$eq: ["$var", "INNER"]}}}
],
cursor: {}
})
.cursor.firstBatch.length,
2);
// Test that $project stage can access command-level 'let' variables.
assert.eq(testDB
.runCommand({
aggregate: coll.getName(),
pipeline: [
{
$project: {
"var": {
$cond: {
"if": {$eq: [{$substr: ["$Species", 0, 1]}, "B"]},
then: "$$variable",
"else": "---"
}
}
}
},
{$match: {$expr: {$eq: ["$var", "OUTER"]}}}
],
cursor: {},
"let": {variable: "OUTER"}
})
.cursor.firstBatch.length,
2);
// Test that $project stage can use stage-level and command-level 'let' variables in same command.
assert.eq(testDB
.runCommand({
aggregate: coll.getName(),
pipeline: [
{
$project: {
"var": {
$let: {
vars: {innerVar: "INNER"},
"in": {
$cond: {
"if": {$eq: [{$substr: ["$Species", 0, 1]}, "B"]},
then: {$concat: ["$$innerVar", "$$outerVar"]},
"else": "---"
}
}
}
}
}
},
{$match: {$expr: {$eq: ["$var", "INNEROUTER"]}}}
],
cursor: {},
"let": {outerVar: "OUTER"}
})
.cursor.firstBatch.length,
2);
// Test that $project stage follows variable scoping rules with stage-level and command-level 'let'
// variables.
assert.eq(testDB
.runCommand({
aggregate: coll.getName(),
pipeline: [
{
$project: {
"var": {
$let: {
vars: {variable: "INNER"},
"in": {
$cond: {
"if": {$eq: [{$substr: ["$Species", 0, 1]}, "B"]},
then: "$$variable",
"else": "---"
}
}
}
}
}
},
{$match: {$expr: {$eq: ["$var", "INNER"]}}}
],
cursor: {},
"let": {variable: "OUTER"}
})
.cursor.firstBatch.length,
2);
// Test that the find command works correctly with a let parameter argument.
let result = assert
.commandWorked(testDB.runCommand({
find: coll.getName(),
let : {target_species: "Song Thrush (Turdus philomelos)"},
filter: {$expr: {$eq: ["$Species", "$$target_species"]}},
projection: {_id: 0}
}))
.cursor.firstBatch;
expectedResults = {
Species: "Song Thrush (Turdus philomelos)",
population_trends: [
{term: {start: 1970, end: 2014}, pct_change: -53, annual: -1.7, trend: "weak decline"},
{term: {start: 2009, end: 2014}, pct_change: -4, annual: -0.88, trend: "no change"}
]
};
assert.eq(result.length, 1);
assert.eq(expectedResults, result[0]);
// Delete tests with let params will delete a record, assert that a point-wise find yields an empty
// result, and then restore the collection state for further tests down the line. We can't exercise
// a multi-delete here (limit: 0) because of failures in sharded txn passthrough tests.
assert.commandWorked(testDB.runCommand({
delete: coll.getName(),
let : {target_species: "Song Thrush (Turdus philomelos)"},
deletes: [{q: {$and: [{_id: 4}, {$expr: {$eq: ["$Species", "$$target_species"]}}]}, limit: 1}]
}));
assert.eq(testDB.runCommand({find: coll.getName(), filter: {$expr: {$eq: ["$_id", "4"]}}})
.cursor.firstBatch.length,
0);
// Test that reserved names are not allowed as let variable names.
assert.commandFailedWithCode(
testDB.runCommand(
{aggregate: coll.getName(), pipeline: [], cursor: {}, let : {Reserved: "failure"}}),
16867);
assert.commandFailedWithCode(
testDB.runCommand(
{aggregate: coll.getName(), pipeline: [], cursor: {}, let : {NOW: "failure"}}),
16867);
assert.commandFailedWithCode(
testDB.runCommand(
{aggregate: coll.getName(), pipeline: [], cursor: {}, let : {CLUSTER_TIME: "failure"}}),
16867);
assert.commandFailedWithCode(
testDB.runCommand(
{aggregate: coll.getName(), pipeline: [], cursor: {}, let : {IS_MR: "failure"}}),
16867);
assert.commandFailedWithCode(
testDB.runCommand(
{aggregate: coll.getName(), pipeline: [], cursor: {}, let : {JS_SCOPE: "failure"}}),
16867);
assert.commandFailedWithCode(
testDB.runCommand(
{aggregate: coll.getName(), pipeline: [], cursor: {}, let : {ROOT: "failure"}}),
16867);
assert.commandFailedWithCode(
testDB.runCommand(
{aggregate: coll.getName(), pipeline: [], cursor: {}, let : {REMOVE: "failure"}}),
16867);
// Test that let variables can be used within views.
assert.commandWorked(testDB.runCommand({
create: "core-viewColl",
viewOn: coll.getName(),
pipeline: [{$match: {Species: "Song Thrush (Turdus philomelos)"}}]
}));
assert.commandWorked(testDB.runCommand({
aggregate: "core-viewColl",
pipeline: [{$addFields: {var : "$$variable"}}],
let : {variable: "Song Thrush"},
cursor: {}
}));
}());