Local queries (#641)

* Read local queries from pgweb home directory
* Refactor local query functionality
* Allow picking local query in the query tab
* WIP
* Disable local query dropdown during execution
* Only allow local queries running in a single session mode
* Add middleware to enforce local query endpoint availability
* Fix query check
* Add query store tests
* Make query store errors portable
* Skip building specific tests on windows

pkg/queries/query_test.go

@@ -0,0 +1,77 @@
+package queries
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestQueryIsPermitted(t *testing.T) {
+	examples := []struct {
+		name     string
+		query    Query
+		args     []string
+		expected bool
+	}{
+		{
+			name:     "no input provided",
+			query:    makeQuery("localhost", "someuser", "somedb", "default"),
+			args:     makeArgs("", "", "", ""),
+			expected: false,
+		},
+		{
+			name:     "match on host",
+			query:    makeQuery("localhost", "*", "*", "*"),
+			args:     makeArgs("localhost", "user", "db", "default"),
+			expected: true,
+		},
+		{
+			name:     "match on full set",
+			query:    makeQuery("localhost", "user", "database", "mode"),
+			args:     makeArgs("localhost", "someuser", "somedb", "default"),
+			expected: false,
+		},
+		{
+			name:     "match on partial database",
+			query:    makeQuery("localhost", "*", "myapp_*", "*"),
+			args:     makeArgs("localhost", "user", "myapp_development", "default"),
+			expected: true,
+		},
+		{
+			name:     "match on full set but not mode",
+			query:    makeQuery("localhost", "*", "*", "readonly"),
+			args:     makeArgs("localhost", "user", "db", "default"),
+			expected: false,
+		},
+	}
+
+	for _, ex := range examples {
+		t.Run(ex.name, func(t *testing.T) {
+			result := ex.query.IsPermitted(ex.args[0], ex.args[1], ex.args[2], ex.args[3])
+			assert.Equal(t, ex.expected, result)
+		})
+	}
+}
+
+func makeArgs(vals ...string) []string {
+	return vals
+}
+
+func makeQuery(host, user, database, mode string) Query {
+	mustfield := func(input string) field {
+		f, err := newField(input)
+		if err != nil {
+			panic(err)
+		}
+		return f
+	}
+
+	return Query{
+		Meta: &Metadata{
+			Host:     mustfield(host),
+			User:     mustfield(user),
+			Database: mustfield(database),
+			Mode:     mustfield(mode),
+		},
+	}
+}