fix(core): repair nesting of flux expressions

CHANGELOG.md

@@ -11,6 +11,7 @@
 1. [#237](https://github.com/influxdata/influxdb-client-js/pull/237): Fixed line splitter of query results that might have produced wrong results for query responses with quoted data.
 1. [#242](https://github.com/influxdata/influxdb-client-js/pull/242): Repair escaping of backslash in line protocol string field.
 1. [#246](https://github.com/influxdata/influxdb-client-js/pull/246): Throw error on attempt to write points using a closed WriteApi instance.
+1. [#252](https://github.com/influxdata/influxdb-client-js/pull/252): Repair nesting of flux expressions.
 
 ## 1.6.0 [2020-08-14]
 

packages/core/src/query/flux.ts

@@ -28,6 +28,15 @@ class FluxParameter implements FluxParameterLike, ParameterizedQuery {
   }
 }
 
+/**
+ * Checks if the supplied object is FluxParameterLike
+ * @param value - any value
+ * @returns true if it is
+ */
+function isFluxParameterLike(value: any): boolean {
+  return typeof value === 'object' && typeof value[FLUX_VALUE] === 'function'
+}
+
 /**
  * Escapes content of the supplied string so it can be wrapped into double qoutes
  * to become a [flux string literal](https://docs.influxdata.com/flux/v0.65/language/lexical-elements/#string-literals).
@@ -222,7 +231,9 @@ export function flux(
   strings: TemplateStringsArray,
   ...values: any
 ): ParameterizedQuery {
-  if (strings.length == 1 && (!values || values.length === 0)) return strings[0] // the simplest case
+  if (strings.length == 1 && (!values || values.length === 0)) {
+    return fluxExpression(strings[0]) // the simplest case
+  }
   const parts = new Array<string>(strings.length + values.length)
   let partIndex = 0
   for (let i = 0; i < strings.length; i++) {
@@ -241,9 +252,12 @@ export function flux(
       } else {
         sanitized = toFluxValue(val)
         if (sanitized === '') {
-          throw new Error(
-            `Unsupported parameter literal '${val}' at index: ${i}, type: ${typeof val}`
-          )
+          // do not allow to insert empty strings, unless it is FluxParameterLike
+          if (!isFluxParameterLike(val)) {
+            throw new Error(
+              `Unsupported parameter literal '${val}' at index: ${i}, type: ${typeof val}`
+            )
+          }
         }
       }
       parts[partIndex++] = sanitized

packages/core/test/unit/query/flux.test.ts

@@ -127,37 +127,78 @@ describe('Flux Values', () => {
 })
 
 describe('Flux Tagged Template', () => {
-  expect(
-    flux`from(bucket:"my-bucket") |> range(start: 0) |> filter(fn: (r) => r._measurement == "temperature")`.toString(),
-    'from(bucket:"my-bucket") |> range(start: 0) |> filter(fn: (r) => r._measurement == "temperature")'
-  )
-  expect(
-    flux`from(bucket:"my-bucket") |> range(start: ${0}) |> filter(fn: (r) => r._measurement == ${'temperature'})`.toString(),
-    'from(bucket:"my-bucket") |> range(start: 0) |> filter(fn: (r) => r._measurement == "temperature")'
-  )
-  expect(
-    flux`from(bucket:"my-bucket") |> range(start: ${0}) |> filter(fn: (r) => r._measurement == "${'temperature'}")`.toString(),
-    'from(bucket:"my-bucket") |> range(start: 0) |> filter(fn: (r) => r._measurement == "temperature")'
-  )
-
-  try {
-    flux`${undefined}`
-    expect.fail()
-  } catch (_e) {
-    // ok expected, undefined is not supported
-  }
-
-  try {
-    flux((['1', '2'] as any) as TemplateStringsArray)
-    expect.fail()
-  } catch (_e) {
-    // ok expected, too few arguments supplied to a tagged template
-  }
+  it('creates a string from a simple string', () => {
+    expect(
+      flux`from(bucket:"my-bucket") |> range(start: 0) |> filter(fn: (r) => r._measurement == "temperature")`.toString()
+    ).equals(
+      'from(bucket:"my-bucket") |> range(start: 0) |> filter(fn: (r) => r._measurement == "temperature")'
+    )
+  })
+  it('interpolates a number', () => {
+    expect(
+      flux`from(bucket:"my-bucket") |> range(start: ${0}) |> filter(fn: (r) => r._measurement == ${'temperature'})`.toString()
+    ).equals(
+      'from(bucket:"my-bucket") |> range(start: 0) |> filter(fn: (r) => r._measurement == "temperature")'
+    )
+  })
+  it('interpolates a string', () => {
+    expect(
+      flux`from(bucket:${'my-bucket'}) |> range(start: 0) |> filter(fn: (r) => r._measurement == ${'temperature'})`.toString()
+    ).equals(
+      'from(bucket:"my-bucket") |> range(start: 0) |> filter(fn: (r) => r._measurement == "temperature")'
+    )
+  })
+  it('interpolates a wrapped string', () => {
+    expect(flux`from(bucket:"${'my-bucket'}")`.toString()).equals(
+      'from(bucket:"my-bucket")'
+    )
+  })
+  it('fails on undefined', () => {
+    try {
+      flux`${undefined}`
+      expect.fail()
+    } catch (_e) {
+      // ok expected, undefined is not supported
+    }
+  })
+  it('fails on empty toString', () => {
+    try {
+      const x = {
+        toString(): string {
+          return ''
+        },
+      }
+      flux`${x}`
+      expect.fail()
+    } catch (_e) {
+      // ok expected, undefined is not supported
+    }
+  })
+  it('fails on wrong usage of template', () => {
+    try {
+      flux((['1', '2'] as any) as TemplateStringsArray)
+      expect.fail()
+    } catch (_e) {
+      // ok expected, too few arguments supplied to a tagged template
+    }
+  })
 
-  // nested flux templates
-  const flux1 = flux`from(bucket:"my-bucket")`
-  expect(
-    flux`${flux1} |> range(start: ${0})")`.toString(),
-    'from(bucket:"my-bucket") |> range(start: 0)")'
-  )
+  it('processes a simple nested flux template', () => {
+    const flux1 = flux`from(bucket:"my-bucket")`
+    expect(flux`${flux1} |> range(start: ${0})")`.toString()).equals(
+      'from(bucket:"my-bucket") |> range(start: 0)")'
+    )
+  })
+  it('processes a parameterized nested flux template', () => {
+    const flux1 = flux`from(bucket:${'my-bucket'})`
+    expect(flux`${flux1} |> range(start: ${0})")`.toString()).equals(
+      'from(bucket:"my-bucket") |> range(start: 0)")'
+    )
+  })
+  it('processes an empty nested flux template', () => {
+    const empty = flux``
+    expect(flux`from(bucket:"my-bucket")${empty}`.toString()).equals(
+      'from(bucket:"my-bucket")'
+    )
+  })
 })