refactor and unify how query strings are formed

src/services/api/helpers.js

@@ -1,5 +1,71 @@
+import { snakeCase } from 'lodash'
+
 import { RegistrationError, StatusCodeError } from 'src/services/errors/errors'
 
+export const paramsString = (params = {}) => {
+  if (params == null || params === undefined) return ''
+
+  if (typeof params !== 'object' || Array.isArray(params)) {
+    throw new Error('Params are not an object!')
+  }
+
+  const entries = (() => {
+    if (params instanceof Map) {
+      return params.entries()
+    } else {
+      return Object.entries(params)
+    }
+  })()
+
+  if (entries.length === 0) return ''
+
+  const arrays = []
+  const nonArrays = []
+
+  entries.forEach(([k, v]) => {
+    if (v == null) return // Drop nulls
+    if (
+      (typeof v === 'object' && !Array.isArray(v)) ||
+      typeof v === 'function'
+    ) {
+      throw new Error('Param cannot be non-primitive!')
+    }
+    if (Array.isArray(v)) {
+      arrays.push([k, v])
+    } else {
+      nonArrays.push([k, v])
+    }
+  })
+
+  arrays.forEach(([k, array]) => {
+    array.forEach((v) => {
+      if (
+        typeof v === 'object' ||
+        typeof v === 'function' ||
+        typeof v === 'undefined'
+      )
+        throw new Error('Array param cannot contain non-primitives!')
+    })
+  })
+
+  return (
+    '?' +
+    [
+      ...nonArrays.map(([k, v]) => [snakeCase(k), v]),
+      // turning [a,[1,2,3]] into [[a[],1],[a[],2],[a[],3]]
+      ...arrays.reduce(
+        (acc, [k, arrayValue]) => [
+          ...acc,
+          ...arrayValue.map((v) => [snakeCase(k) + '[]', v]),
+        ],
+        [],
+      ),
+    ]
+      .map(([k, v]) => `${k}=${window.encodeURIComponent(v)}`)
+      .join('&')
+  )
+}
+
 export const promisedRequest = ({
   method,
   url,